Physiographic Modulation of Soil Hydro-redox Conditions and Compost-induced Microbial Dynamics, Enzyme Activity, Nutrient Uptake in Okra

Physiographic Modulation of Soil Hydro-redox Conditions and Compost-induced Microbial Dynamics, Enzyme Activity, Nutrient Uptake in Okra | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Physiographic Modulation of Soil Hydro-redox Conditions and Compost-induced Microbial Dynamics, Enzyme Activity, Nutrient Uptake in Okra James Ukwumonu Yahaya, Oluyemisi Bolajoko Fawole, Isiaka Kareem, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9214501/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 9 You are reading this latest preprint version Abstract Physiographic gradients strongly influence soil hydro-redox conditions, yet their interaction with organic amendments in tropical savannas remains poorly understood. This study evaluated how slope position modulates compost-induced microbial enzyme activity, nutrient uptake, and vegetative growth of okra ( Abelmoschus esculentus L.) in a southern Guinea savanna soil. A 3 × 2 factorial experiment (crest, backslope, toeslope × 0 or 20 t ha -1 compost) was conducted under screenhouse conditions with three replicates over 8 weeks. Soil moisture, estimated redox potential (Eh), microbial frequency, enzyme activities (cellulase and protease), nutrient uptake, and vegetative growth parameters were assessed. Compost application significantly increased soil moisture, enzyme activity, nutrient uptake, and plant growth across all positions (P ≤ 0.001). Moisture consistently followed the gradient toeslope > backslope > crest, while estimated Eh showed an inverse trend. Cellulase and protease activities were highest in compost-amended toeslope soils and were strongly associated with soil moisture (r ≥ 0.99; P ≤ 0.001). In contrast, microbial frequency showed weak, non-significant relationships with enzyme activity and plant performance. Nitrogen, phosphorus, and potassium uptake increased by 28-36% under compost application, with the greatest response observed in backslope and toeslope soils. Vegetative growth parameters exhibited similar spatial patterns. The results demonstrate a physiography-driven biogeochemical cascade in which soil moisture and redox conditions regulate enzyme-mediated nutrient mineralization and crop response. These findings highlight that compost effectiveness is strongly dependent on landscape position and emphasize the need for site-specific soil fertility management in tropical agroecosystems. Compost soil physiography hydro-redox conditions microbial-enzyme interactions nutrient mineralisation okra Guinea Savanna Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Highlights Physiographic position strongly regulates compost effectiveness in tropical soils Soil moisture and redox conditions drive enzyme-mediated nutrient mineralization Enzyme activity, not microbial frequency, predicts nutrient uptake and plant growth Compost effects follow a consistent gradient: toeslope > backslope > crest Landscape-specific compost management improves nutrient use efficiency Introduction Organic amendments are critical tools for improving soil fertility, enhancing nutrient cycling, and promoting sustainable crop productivity in tropical agroecosystems (Zhou et al., 2021 ; Yang et al., 2023 ). Poultry-manure-based compost, in particular, provides a rich source of organic carbon, nitrogen, and micronutrients, while simultaneously acting as a microbial inoculum to stimulate soil biological activity (Adewole & Ilesanmi, 2012 ; Nengi-Benwari & Abah, 2025 ). Despite widespread adoption, the agronomic effectiveness of compost is often uneven, with crop response varying according to soil properties, landscape position, and microenvironmental conditions (Belay et al., 2025 ; Cai et al., 2025 ). Soil physiography strongly influences hydrological dynamics, redox potential, and microbial processes along slope positions (Bufebo et al., 2021 ; Suvendran et al., 2025 ). Crest soils tend to be drier and more oxidized, limiting sustained microoxic zones, whereas backslope and toeslope soils retain higher moisture and exhibit lower redox potentials, creating favorable conditions for microbial proliferation and enzymatic activity (Dorau et al., 2018; Omokaro, 2023 ; Okebalama et al., 2025 ). These differences establish distinct soil microenvironments that regulate nutrient mineralization, substrate availability, and plant nutrient acquisition (Bhanwaria et al., 2022 ). The role of physiographic heterogeneity in shaping the effectiveness of organic amendments remains poorly quantified in tropical cropping systems. Compost maturation dynamics directly influence soil biochemical functioning. Thermophilic decomposition of labile carbon fractions, progressive mineralization of nitrogen, and stabilization of heavy metals collectively determine compost stability, nutrient release patterns, and environmental safety (Papale et al., 2021 ; Wang et al., 2024 ; Jakubus, 2020 ; Ouali et al., 2025 ; Okoro et al., 2025 ). Incorporation of mature compost into soil not only contributes nutrients but also modifies soil structure, enhances water retention, and facilitates microbial colonization. Increased water-holding capacity and stabilized soil aggregates extend moisture residence times, moderate redox fluctuations, and improve conditions for both fungal and bacterial growth (Li et al., 2021 ; Chen et al., 2023 ; Xu et al., 2023 ). Microbial-enzyme interactions are central to nutrient mineralization in amended soils. Fungal taxa such as Aspergillus, Trichoderma , and Cladosporium efficiently decompose complex substrates, while bacterial genera including Bacillus, Pseudomonas , and Streptomyces solubilize nutrients and promote plant growth (Chauhan et al., 2023 ; Chen et al., 2023 ). Enzymes such as cellulase and protease serve as functional indicators of carbon and nitrogen turnover, with their activities strongly influenced by soil moisture and redox potential (Zhang et al., 2018 ; Tamura & Suseela, 2021 ; Solangi et al., 2024 ). Moderate declines in redox potential promote microoxic zones that enhance enzyme stability, facilitate substrate diffusion, and support facultative microbial metabolisms (Liu et al., 2023 ; Rahman & Thomas, 2021 ). The interaction between landscape position, moisture, and redox potential further modulates nutrient availability and plant uptake. Toposequence-driven differences in microclimate create spatial variability in microbial and enzymatic responses, resulting in differential nitrogen, phosphorus, and potassium availability for crops such as okra (Borowik & Wyszkowska, 2016 ; Zhang et al., 2018 ; Bufebo et al., 2021 ; Bogati et al., 2025 ). Positive associations between microbial enzyme activities and nutrient uptake indicate that compost-mediated nutrient transformations are a key driver of improved plant performance, emphasizing the importance of integrating hydrological and biochemical controls into organic amendment strategies (Chen et al., 2024 ; Bogati et al., 2025 ). Despite the recognized benefits of compost, previous studies often overlook the mechanistic cascade linking amendment, microbial proliferation, enzymatic activity, nutrient mineralization, and plant growth across contrasting physiographic positions (Guo et al., 2022 ; Bogati et al., 2024 ; Wang et al., 2023 ). Furthermore, intermediate nutrient pools, such as ammonium, nitrate, and soluble phosphorus, are rarely quantified in situ, limiting mechanistic understanding. Comprehensive assessments that couple soil moisture, redox potential, microbial-enzyme interactions, and crop performance are therefore essential to optimize compost management in heterogeneous landscapes (Frimpong et al., 2017 ; Adekiya et al., 2020 ; Ahmed et al., 2023 ; Huang et al., 2025 ). This study hypothesizes that poultry-manure-based compost enhances microbial-enzyme activity, nutrient mineralization, and okra growth, with the magnitude of these effects modulated by physiographic position. Specifically, we evaluate (i) compost maturation dynamics and their nutrient and heavy metal profiles; (ii) soil microenvironmental changes (moisture, redox, physicochemical properties) following amendment; (iii) microbial frequency, enzyme activity, and nutrient mineralization patterns along a toposequence; and (iv) correlations between soil biochemical processes and okra vegetative performance. Findings from this work aim to provide mechanistic evidence for site-specific organic amendment strategies that optimize nutrient use efficiency and crop productivity in tropical smallholder farming systems. Materials and Methods Study area and soil sampling The study was carried out in the screenhouse of the Department of Agronomy, Faculty of Agriculture, University of Ilorin, Nigeria (8º29′ N, 4º40′ E; 307 m above sea level). The location lies within the southern Guinea savanna agroecological zone. The region is characterized by tropical climate with distinct wet and dry seasons and an average annual rainfall of approximately 1200 mm. Surface soils (0–20 cm) were collected from three distinct physiographic positions within the University of Ilorin Teaching and Research Farm: crest (8º29′35″ N, 4º39′55″ E) for the crest, backslope (8º29′28″ N, 4º40′05″ E) and toeslope (8º29′22″ N, 4º40′13″ E). At each position, five subsamples were randomly collected along a 50 m transect using a soil auger, composited, air-dried, gently crushed, and sieved through a 2 mm mesh. The processed soils were stored in labelled polythene bags prior to use. Baseline physicochemical properties of the soils were determined using standard procedures (Table 1 ). Table 1 Baseline physicochemical properties of soils across crest, backslope, and toeslope positions before compost application Sampling points Moisture pH Bulk Density Organic C Total N Available P C/N ratio K Ca Mg Na (%) (kg m − 1 ) (mg kg − 1 ) (cmol kg − 1 ) Crest 8.5 6.2 1520 15000 1200 9 12.5 0.19 4.25 1.15 0.13 Backslope 12.0 6.5 1310 18500 1500 12 12.3 0.28 6.00 1.65 0.20 Toeslope 18.5 6.8 1030 22000 1900 16 11.6 0.38 8.00 2.30 0.26 LSD (P ≤ 0.05) 8.87 *** 74.25 *** 18.13 *** 18.11 *** 15.12 *** 12.16 *** 74.75 *** 10.31 *** 11.23 *** 10.19 *** 10.39 *** *** = significance at P ≤ 0.001 Poultry manure-based compost production and characterization Compost was produced using poultry manure and selected crop residues through twelve weeks of aerobic decomposition. Poultry manure (< 24 hours old) and grass clippings were collected from the University of Ilorin Teaching and Research Farm, while rice bran, sawdust, and cassava peels were sourced from major markets within Ilorin. Rice bran was collected from Oja Gboro Market, sawdust from Irewolede sawmill, and cassava peels from the General Market. All materials were collected in clean, labelled polyethylene bags and transported to the laboratory. Each residue was weighed and ground using a mechanical grinder to enhance microbial colonization and uniform mixing. A cylindrical pit measuring 50 cm × 100 cm was dug at the composting site. A perforated dark plastic bucket was placed centrally within the pit to promote passive aeration and temperature retention. The feedstocks were mixed and arranged in alternating layers inside the composting bucket at a ratio of 1:5 (w/w) corresponding to 16.67% poultry manure and 83.33% plant residues. A base layer of 1 kg of poultry manure was placed in the bucket and covered with 5 kg of sawdust. Additional layers were added in the following sequence: 1 kg of poultry manure covered with 5 kg of grass clippings, followed by another 1 kg of poultry manure covered with 5 kg of shredded cassava peels, and another 1 kg of poultry manure covered with 5 kg of rice husk. Layering continued until all materials were exhausted. The space between the basket and the walls of the pit was filled with sawdust to provide insulation. The composting mass was lightly moistened to achieve approximately 60% field capacity and maintained throughout the period by intermittent application of clean water using a calibrated 1-liter container. Additional wetting with approximately 0.5 litres was done whenever the pile showed signs of dehydration. The buckets were covered with a black plastic bag to conserve heat and minimize evaporation. Aeration was enhanced by manually turning the compost every two days during the first two weeks and every seven days thereafter, using a disinfected wooden paddle. Temperature was monitored biweekly using a calibrated soil thermometer, which was inserted for five minutes before reading. Compost subsamples were taken at weeks 0, 2, 4, 6, 8, 10, and 12 for physicochemical assessment. Organic carbon was determined by the Walkley-Black method. Total nitrogen was determined by the Kjeldahl digestion method. Available phosphorus was quantified using the Bray 1 extractant. Exchangeable cations (K, Ca, Mg, and Na) were extracted using 1 M ammonium acetate and analysed by flame photometry (K, Na) and atomic absorption spectrophotometry (Ca, Mg). Heavy metals (Zn, Pb, Cd, Cr, Cu, and Ni) were analysed using atomic absorption spectrophotometry following wet digestion. Moisture content was determined gravimetrically, and pH was measured in a 1:2.5 compost-to-water suspension. At week 12, the matured compost was air-dried, sieved (2 mm), and analysed for proximate composition. Moisture, ash, protein, fat, and crude fibre were determined according to AOAC (2004). Carbohydrates were computed by difference following FAO (2004): $$\:\%Carbohydrate=100-\:\left(\%Moisture+\%Ash+\%Protein+\%Fat\right)$$ The physicochemical properties of the feedstocks and the temporal changes in compost properties, heavy metal concentrations, and exchangeable bases are presented in Tables 2 , 3 , 4 , and 5 . Table 2 Physicochemical characteristics of compost feedstocks used in formulation Parameters Moisture pH Bulk Density Organic C Total N Ash C/N ratio Available P K Ca Mg Na (%) (kg m − 3 ) mg kg − 1 cmol kg − 1 Poultry Manure 70.2 7.1 550 380000 26500 250000 14.34 4800 12.28 107.50 289.30 36.52 Cassava Peels 68.5 5.3 420 410000 9200 60000 44.57 2300 5.88 79.00 78.97 20.43 Saw Dust 55.7 5.8 310 465000 2100 20000 221.43 900 2.30 17.50 34.57 6.96 Rice Bran 64.3 6.2 380 395000 11800 100000 33.47 2700 6.90 91.00 119.34 26.96 Grass Clippings 73.9 6.5 290 360000 17200 120000 20.93 3100 7.93 98.00 105.36 22.17 LSD (P ≤ 0.05) 39.96 *** 37.79 *** 15.73 *** 42.27 *** 6.12 *** 5.28 *** 3.21 *** 8.19 *** 9.21 *** 5.40 *** 8.80 *** 6.31 *** *** = significance at P ≤ 0.001 Table 3 Temporal variation in physicochemical properties of composting materials during aerobic decomposition (0–12 weeks) Time Temperature pH Moisture content Total N Total OC Available P C/N ratio (week) ( o C) (%) mg kg − 1 0 28.50 6.80 55.00 1480 25800 450 17.4 2 68.87 7.52 35.70 1580 23600 520 14.6 4 62.00 7.21 34.31 1830 21400 610 11.7 6 48.00 7.16 33.07 1950 19800 700 10.2 8 39.50 7.05 31.90 2010 18200 780 9.1 10 33.00 6.95 30.80 2070 16700 840 8.1 12 29.00 6.85 29.50 2120 13500 900 6.4 t-stat (p ≤ 0.05) 13.20 *** 137.19 *** 19.76 *** 36.44 *** 22.94 *** 13.71 *** 19.82 *** *** = significance at P ≤ 0.001 Table 4 Temporal changes in heavy metal concentrations and exchangeable base cations during composting (0–12 weeks) Time Heavy Metal Reduction Exchangeable bases (week) (mg kg − 1 ) (cmol kg − 1 ) Zn Pb Cd Cr Cu Ni Ca Mg K Na 0 145 62 4.8 22 118 18 12.5 4.2 2.8 0.6 2 132 56 4.2 20 110 16 13.6 4.5 3.4 0.7 4 120 49 3.7 18 101 14 14.4 4.9 4.0 0.8 6 109 43 3.3 16 94 13 15.1 5.2 4.5 0.9 8 98 38 2.9 15 87 12 15.8 5.5 4.8 1.0 10 89 34 2.6 14 81 10 16.3 5.7 5.0 1.0 12 82 30 2.3 12 75 9 16.7 5.9 5.2 1.1 LSD (P ≤ 0.05) 23.24 *** 18.37 *** 18.30 *** 23.02 *** 29.55 *** 19.89 *** 47.54 *** 39.29 *** 23.10 *** 22.94 *** *** = significance at P ≤ 0.001 Table 5 Proximate composition of matured compost at week 12 (wet basis) Parameters % Composition (w/w) LSD (P ≤ 0.05) Moisture 32.00 1108.51 *** Ash 25.00 866.03 *** Protein 1.33 76.79 *** Fat 2.50 108.25 *** Crude fibre 16.00 923.76 *** Carbohydrates 23.17 1337.72 *** *** = significance at P ≤ 0.001 Plant materials and source Seeds of okra ( Abelmoschus esculentus L. Moench., variety Clemson Spineless) used in this study were obtained from a certified agricultural input supplier in Ilorin, Kwara State, Nigeria. The seeds are commercially cultivated and widely distributed for agricultural puproses. All experimental soils were collected from the University of Ilorin Teaching and Research Farm, located at crest (8º29′35″ N, 4º39′55″ E), backslope (8º29′28″ N, 4º40′05″ E) and toeslope (8º29′22″ N, 4º40′13″ E) positions. No wild plant species were collected from natural ecosystems for this study. The okra plants used in the experiment were cultivated entirely under controlled screenhouse conditions. Experimental design and setup The experiment followed a 3 × 2 factorial arrangement in a completely randomized design. The factors were physiographic position (crest, backslope, and toeslope) and compost level (0 and 20 t ha⁻¹). Each treatment combination was replicated three times, resulting in a total of 18 pots. Plastic pots (15 cm diameter) were filled with 5 kg of sieved soil. Compost was incorporated into the top 10 cm layer of soil in the amended pots at the equivalent rate of 20 t ha − 1 . The amended and control soils were pre-incubated for two weeks to allow microbial and chemical stabilization. No mineral fertilizer was applied. Seeds of okra ( Abelmoschus esculentus L. Moench., variety Clemson Spineless) were sown directly into the pots at three seeds per hole and later thinned to one healthy seedling per pot. All pots were irrigated daily to maintain field capacity. Vegetative growth parameters, including plant height, stem girth, number of leaves, leaf length, and leaf width, were recorded at 2-week intervals (2, 4, 6, and 8 weeks after planting). Leaf area and leaf area index were computed using standard agronomic formulae. Empirical estimation of soil redox potential Soil redox potential (Eh) was not directly measured using platinum electrodes in this study. Instead, Eh values were estimated empirically from soil moisture content using site-specific regression models. Empirical prediction of Eh from moisture or water-filled pore space has been applied in ecological and soil biogeochemical studies where direct electrode measurements are unavailable (Patrick & Reddy, 1978; Husson, 2013; Khan & Hossain, 2020). Given the well-established inverse relationship between soil aeration and moisture content, separate linear models were fitted for each physiographic position (crest, backslope, toeslope), incorporating soil moisture and compost level as predictors (Masschelyleyn et al., 1991; Reddy & DeLaune, 2008 ). Compost was coded as 0 (control) or 1 (20 t ha⁻¹). The general model was: $$\:Eh\:\left(mV\right)\:=a-b\:\left(moisture\right)+c\left(compost\right)$$ was fitted using ordinary least squares (OLS) for each slope position. Compost was coded as 0 (control) or 1 (20 t ha − 1 ). where Eh represents estimated redox potential (mV), a is the intercept, b represents the rate of Eh decline per unit increase in soil moisture, and c represents the compost-induced redox adjustment factor. These models provide relative comparisons of redox dynamics across slope positions but should be interpreted as predictive approximations rather than direct electrochemical measurements. Consequently, associations between Eh and other variables should be interpreted within the context of model-derived estimation rather than independently measured redox potential. The moisture content and Eh values for the three physiographic positions are shown in Table 6 . Nutrient uptake and post-harvest soil analysis Plants were harvested at eight weeks after sowing. Shoots and roots were washed with distilled water, oven-dried at 65°C to a constant weight, and then ground. Total nitrogen was determined by the Kjeldahl method (Bremner, 1965), phosphorus by the molybdenum blue method (Murphy & Riley, 1962), and potassium by flame photometry (Black, 1965). Nutrient uptake was calculated as: $$\:Uptake\:\left({mg\:plant}^{-1}\right)\:=Dry\:matter\:\left({g\:plant}^{-1}\right)\:\times\:Nutrient\:concentration\:\left({mg\:g}^{-1}\right)$$ The results of nutrient uptake are presented in Table 7 . Post-harvest soils were sampled, air-dried, sieved (2 mm), and analyzed for pH (1:2.5 soil: water), organic carbon (Walkley-Black method), total nitrogen (Kjeldahl method), available phosphorus (Bray-1 method), and exchangeable potassium (1 N ammonium acetate extraction). The results are shown in Table 8 . Microbial frequency and enzyme activity assays Soil samples collected at 0, 2, 4, 6, and 8 weeks after compost application were used to determine microbial population and enzyme activities. Serial dilutions were prepared to 10 − 3 and 10 − 6 for bacteria and fungi. Bacteria were isolated on nutrient agar and incubated at 35 ± 2 o C for 24 to 48 hours. Fungi were isolated on potato dextrose agar amended with streptomycin (100 mg/L) and incubated at 28 ± 2°C for 72 to 120 hours. Distinct colonies were purified through subculturing and identified by their cultural, biochemical, and microscopic characteristics. The percentage frequency of occurrence was calculated as: $$\:Frequency\:\left(\:\%\right)\:=\:\frac{Number\:of\:isolates\:of\:a\:species}{Total\:isolates\:recovered}\times\:100$$ Fungal and bacterial frequency distributions across physiographic positions are presented in Figs. 2 – 4 and 5 – 7 , respectively. Enzyme assays were performed using the same soil samples as described by Tabatabai (1994) and Alef and Nannipieri (1995). Cellulase activity was determined as the rate of reducing sugar formation (µmol glucose g − 1 soil h − 1 ) by the dinitrosalicylic acid method, and protease activity as the rate of tyrosine release from casein (µmol tyrosine g − 1 soil h − 1 ). The results are presented in Figs. 8 and 9 . Statistical analysis Data were subjected to factorial analysis consistent with the 3 × 2 experimental designs (physiographic position × compost level). Treatment effects and their interactions were evaluated using two-way analysis of variance (ANOVA). Where significant main or interaction effects were detected, means were separated using the Least Significant Difference (LSD) test at P ≤ 0.05. Temporal data (0–8 weeks) were analyzed considering sampling time as a repeated factor to account for within-treatment dependence. Pearson correlation coefficients were computed to evaluate associations among soil moisture, estimated redox potential, microbial frequency, enzyme activity, nutrient uptake, and vegetative growth parameters. Because redox potential was derived from moisture-based regression models, interpretation of correlations involving Eh was made cautiously to avoid circular inference. All analyses were performed using GenStat version 12 (VSN International, UK), and graphical outputs were generated using GraphPad Prism. Results Baseline soil physicochemical properties across physiographic positions Baseline soil properties differed significantly across the crest, backslope, and toeslope positions (Table 1 ). A clear downslope gradient was observed, with higher moisture, organic carbon, total nitrogen, and exchangeable bases in the toeslope compared with the crest. Bulk density decreased downslope, indicating improved soil structure in lower landscape positions. Overall, the toeslope exhibited the most favorable initial conditions for biological activity and nutrient availability, while the crest represented a comparatively drier and nutrient-limited environment. Physicochemical properties of compost feedstocks The compost feedstocks showed wide variability in physicochemical properties (Table 2 ), with poultry manure contributing the highest nutrient concentrations and lowest C:N ratio, while sawdust exhibited high carbon content and low nutrient levels. These contrasting properties ensured a balanced substrate composition necessary for effective composting. Compost physicochemical dynamics during aerobic decomposition Composting followed a typical thermophilic pattern, with temperature peaking at Week 2 and declining thereafter (Table 3 ). Organic carbon decreased while total nitrogen and available phosphorus increased, resulting in a marked reduction in C:N ratio, indicating progressive stabilization and maturity of the compost. Moisture content declined steadily over time, reflecting evaporation and microbial utilization. Heavy metal concentration and exchangeable base trends during composting Heavy metal concentrations declined during composting (Table 4 ). These decreases likely reflect dilution, immobilization, and complexation processes rather than true elemental loss. In contrast, exchangeable Ca, Mg, K, and Na increased progressively, indicating mineral enrichment and improved nutrient availability in the matured compost. Proximate composition of mature compost The proximate composition of the mature compost at Week 12 (Table 5 ) showed moisture content of 32%, ash content of 25%, protein 1.33%, fat 2.50%, crude fibre 16%, and carbohydrate 23.17%. All parameters differed significantly from their initial values or expected means (t = 76.79–1337.72; p ≤ 0.001). Soil microenvironmental response to compost application Soil moisture increased over time and was consistently higher in compost-amended soils across all physiographic positions (Table 6 ). A clear gradient of toeslope > backslope > crest was maintained throughout the study. Estimated redox potential (Eh) showed an inverse relationship with moisture and declined over time, with lower values observed in compost-treated soils and in lower slope positions. Soil moisture increased progressively over time in both treatments and across all physiographic positions, with consistently higher values under compost amendment. Correspondingly, Eh declined with increasing moisture, and remained lower in compost-amended soils than in control across all sampling periods. Table 6 Soil moisture content (%) and redox potential (Eh, mV) across physiographic positions under compost treatments during 8 weeks of okra growth Time Compost level Crest Backslope Toeslope Moisture Eh Moisture Eh Moisture Eh (week) (t ha − 1 ) (%) mV (%) mV (%) mV 0 Control (0) 15.80 522.00 18.80 488.00 22.30 434.00 20 17.20 514.00 20.30 476.00 24.50 425.67 2 Control (0) 16.27 511.00 19.50 472.00 23.10 421.00 20 18.93 498.33 21.80 455.67 25.17 409.00 4 Control (0) 17.10 496.33 20.57 461.00 23.90 405.67 20 19.60 472.33 22.50 436.33 26.50 396.00 6 Control (0) 17.77 478.00 21.20 448.00 24.67 392.33 20 20.07 455.33 23.10 422.33 27.20 384.33 8 Control (0) 18.17 465.00 21.80 438.00 25.10 379.00 20 20.47 449.00 23.60 414.00 27.80 371.33 LSD (P ≤ 0.05) 64.04 *** 106.94 *** 77.96 *** 106.94 *** 81.12 *** 109.01 *** *** = significance at P ≤ 0.001 Microbial population dynamics across physiographic positions Fungal frequencies increased progressively over time in all slope positions and were consistently higher under compost amendment (Figs. 1 – 3 ). Compost amendment consistently increased the frequency of all fungal taxa relative to the control. Toeslope soils recorded the highest frequencies, followed by backslope and crest soils. At the crest (Fig. 1 ), Aspergillus niger, Penicillium chrysogenum, Cladosporium spp., Trichoderma viridae , and Rhizopus spp. increased gradually with time. The backslope (Fig. 2 ) exhibited steeper increases, with A. flavus showing pronounced elevation under compost amendment. The toeslope (Fig. 3 ) showed the highest fungal proliferation, with compost consistently producing greater frequencies. Bacterial frequencies followed similar trends (Figs. 4 – 6 ). Compost significantly increased the occurrence of bacteria across all positions. In the crest soils, taxa such as Bacillus spp., Micrococcus spp., Arthrobacter spp., and Pseudomonas spp . exhibited modest increases under the control but showed substantially higher frequencies under compost (Fig. 4 ). At the backslope, compost application resulted in more pronounced increases in Bacillus, Pseudomonas, Enterobacter, Streptomyces , and Paenibacillus compared to the crest position (Fig. 5 ). In the toeslope soils, all bacterial groups displayed the highest overall frequencies, with compost producing a strong and consistent upward trajectory for Pseudomonas, Bacillus, Enterobacter, Streptomyces, and Paenibacillus across sampling times (Fig. 6 ). As with fungi, bacterial frequency patterns followed the hierarchy toeslope > backslope > crest, with compost consistently amplifying frequencies relative to the controls. Soil enzyme activities Cellulase and protease activities increased with time and were consistently higher in compost-amended soils (Figs. 7 and 8 ). Activities were greatest in the toeslope, followed by backslope and crest positions. This pattern mirrors moisture availability and suggests strong environmental regulation of enzyme expression. Vegetative growth responses of okra Okra vegetative growth parameters responded positively to compost treatment and were influenced by physiographic position (Figs. 9 – 13 ). Plant height increased progressively from week 2 to week 8 in all treatments (Fig. 9 ). Compost-amended soils consistently produced taller plants than the control in the crest, backslope, and toeslope positions. The highest plant heights were recorded in the toeslope, followed by the backslope, with the crest producing the shortest plants. Stem girth followed a similar pattern (Fig. 10 ). Compost-treated plants had wider stems than the control at all slope positions, and the toeslope maintained the largest girth values at each sampling time. The number of leaves increased with time and was higher in compost-amended soils than in unamended soils (Fig. 11 ). The toeslope position recorded the highest number of leaves. Leaf area increased with plant age, with compost treatments producing larger leaf areas in all positions (Fig. 12 ). Toeslope soils supported the largest leaf areas, followed by backslope and crest. Leaf area index (LAI) increased steadily across sampling dates, with compost producing higher LAI in all positions (Fig. 13 ). Toeslope soils recorded the highest LAI values. Nutrient Uptake by Okra Across Physiographic Positions and Compost Levels Compost application significantly increased N, P, and K uptake across all physiographic positions (Table 7 ). Nutrient uptake followed the same spatial trend observed for soil moisture and enzyme activity, with higher uptake in backslope and toeslope soils relative to crest soils. Table 7 Nitrogen, phosphorus, and potassium uptake by okra under compost treatments across physiographic positions Physiographic positions Compost level N P K (t ha − 1 ) mg plant − 1 Crest Control (0) 35.63 18.70 26.80 20 48.27 26.40 33.93 Backslope Control (0) 44.73 24.10 34.83 20 58.43 32.57 41.70 Toeslope Control (0) 42.10 21.30 31.60 20 55.20 29.40 38.90 LSD (P ≤ 0.05) 25.32 *** 22.34 *** 29.62 *** *** = significance at P ≤ 0.001 Post-harvest soil properties following okra cultivation Post-harvest soil properties improved under compost application across all slope positions (Table 8 ). Increases in organic carbon, total nitrogen, available phosphorus, and exchangeable potassium indicate residual fertility benefits of compost amendment. Table 8 Post-harvest soil properties under compost treatments across physiographic positions following okra cultivation Slope positions Compost level pH Organic C Total N Available P Exchangeable K (t ha − 1 ) (mg kg − 1 ) cmol kg − 1 Crest Control (0) 6.50 9400 900 10.47 0.38 20 6.80 12100 1200 14.77 0.51 Backslope Control (0) 6.60 10200 1000 12.37 0.44 20 7.10 13400 1300 17.87 0.58 Toeslope Control (0) 6.70 10800 1100 13.67 0.47 20 7.00 12800 1200 16.47 0.55 t-stat (p ≤ 0.05) 123.38 *** 32.98 *** 34.26 *** 23.83 *** 29.75 *** *** = significance at P ≤ 0.001 Correlation relationships among soil, microbial, enzyme, and plant parameters Across all physiographic positions, soil moisture showed strong positive associations with enzyme activities, nutrient uptake, and vegetative growth parameters (Tables 9 – 11 ). In contrast, estimated redox potential (Eh) exhibited strong negative relationships with these variables. Microbial frequencies displayed weak and non-significant correlations with enzyme activity, nutrient uptake, and plant growth across all slope positions. This indicates that microbial occurrence alone was not a reliable predictor of functional soil processes or plant performance. The strong associations observed among soil moisture, estimated redox potential, enzyme activity, nutrient uptake, and growth parameters indicate closely linked hydro-biogeochemical dynamics across the physiographic gradient. These relationships indicate coordinated environmental controls rather than strictly independent mechanistic effects. Table 9 Pearson correlation coefficients among soil moisture, redox potential, microbial frequency, enzyme activity, nutrient uptake, and okra growth parameters at crest position Properties Fungal frequency Bacterial frequency Soil Moisture Eh (%) (mV) Soil Moisture (%) -0.1570 -0.2686 1.0000 0.0000 Eh (mV) 0.1559 0.3001 -0.9639 1.0000 Cellulase (µg glucose g − 1 soil h − 1 ) -0.1579 -0.2362 0.9922 -0.9733 Protease (µg tyrosine g − 1 soil h − 1 ) -0.1581 -0.2538 0.9983 -0.9675 Plant N (mg plant − 1 ) -0.1582 -0.2628 0.9975 -0.9716 Plant P (mg plant − 1 ) -0.1588 -0.2629 0.9982 -0.9699 Plant K (mg plant − 1 ) -0.1599 -0.2364 0.9948 -0.9624 Plant height (cm) -0.1571 -0.2555 0.9985 -0.9628 Stem girth (cm) -0.1557 -0.2627 0.9982 -0.9466 Number of leaves -0.1515 -0.0583 0.8828 -0.7845 Leaf Area (cm 2 ) -0.1578 -0.2174 0.9920 -0.9337 Leaf Area Index (m 2 /m 2 ) -0.1578 -0.2174 0.9920 -0.9337 LSD (P ≤ 0.05) ns ns <0.001 <0.001 *** = significance at P ≤ 0.001, ns = not significant Table 10 Pearson correlation coefficients among soil moisture, redox potential, microbial frequency, enzyme activity, nutrient uptake, and okra growth parameters at backslope position Properties Fungal frequency Bacterial frequency Soil Moisture Eh (%) (mV) Soil Moisture (%) 0.1386 -0.2177 1.0000 0.0000 Eh (mV) -0.1417 0.2141 -0.9785 1.0000 Cellulase (µg glucose g − 1 soil h − 1 ) 0.1367 -0.2125 0.9956 -0.9888 Protease (µg tyrosine g − 1 soil h − 1 ) 0.1349 -0.2113 0.9936 -0.9890 Plant N (mg plant − 1 ) 0.1364 -0.2133 0.9961 -0.9888 Plant P (mg plant − 1 ) 0.1375 -0.2120 0.9968 -0.9878 Plant K (mg plant − 1 ) 0.1329 -0.2126 0.9943 -0.9842 Plant height (cm) 0.1360 -0.2096 0.9952 -0.9865 Stem girth (cm) 0.1330 -0.2112 0.9949 -0.9827 Number of leaves 0.1498 -0.2112 0.9662 -0.9891 Leaf Area (cm 2 ) 0.1347 -0.2101 0.9947 -0.9861 Leaf Area Index (m 2 /m 2 ) 0.1347 -0.2177 0.9947 -0.9861 LSD (P ≤ 0.05) ns ns <0.001 <0.001 *** = significance at P ≤ 0.001, ns = not significant Table 11 Pearson correlation coefficients among soil moisture, redox potential, microbial frequency, enzyme activity, nutrient uptake, and okra growth parameters at toeslope position Properties Fungal frequency Bacterial frequency Soil Moisture Eh (%) (mV) Soil Moisture (%) 0.1902 0.1758 1.0000 0.0000 Eh (mV) -0.1658 -0.1710 -0.9153 1.0000 Cellulase (µg glucose g − 1 soil h − 1 ) 0.1922 0.1764 0.9991 -0.9181 Protease (µg tyrosine g − 1 soil h − 1 ) 0.1918 0.1759 0.9993 -0.9102 Plant N (mg plant − 1 ) 0.1921 0.1767 0.9993 -0.9205 Plant P (mg plant − 1 ) 0.1924 0.1773 0.9961 -0.9245 Plant K (mg plant − 1 ) 0.1904 0.1756 0.9965 -0.9250 Plant height (cm) 0.1899 0.1764 0.9991 -0.9188 Stem girth (cm) 0.1909 0.1759 0.9982 -0.9103 Number of leaves 0.1991 0.1698 0.9857 -0.8677 Leaf Area (cm 2 ) 0.1934 0.1754 0.9972 -0.8982 Leaf Area Index (m 2 /m 2 ) 0.1934 0.1754 0.9972 -0.8982 LSD (P ≤ 0.05) ns ns <0.001 <0.001 *** = significance at P ≤ 0.001, ns = not significant Discussion Compost maturation dynamics and implications for soil amendment The physicochemical trends observed during composting indicate a well-defined aerobic decomposition process that produced a stable and mature poultry-manure-based compost. The sharp rise in temperature from week 0 to week 2 reflects rapid microbial oxidation of labile carbon, consistent with thermophilic composting reported by Papale et al. ( 2021 ) and Wang et al. ( 2024 ). The subsequent temperature decline indicates the transition to the curing phase as metabolic heat generation reduces. Reductions in organic carbon and the steady increase in total nitrogen lowered the C/N ratio from 17.4 to 6.4, within maturity thresholds reported by Jakubus ( 2020 ) and Ouali et al. ( 2025 ), confirming stability. Heavy metals (Zn, Pb, Cd, Cr, Cu, Ni) declined over compost maturation, consistent with dilution through biomass increase, complexation, and adsorption onto humified organic matter (Okoro et al., 2025 ). Concurrent increases in exchangeable Ca, Mg, K, and Na reflect mineral release, ash enrichment, and retention on soil colloids, contributing to improved cation exchange capacity and nutrient buffering (Jakubus, 2020 ). Soil moisture and redox shifts across physiographic positions Compost application increased soil moisture retention across all physiographic positions, consistent with the role of organic amendments in improving soil structure, porosity, and aggregate stability (Rasa et al., 2024 ; Tao et al., 2024 ). The observed gradient (toeslope > backslope > crest) reflects inherent topographic redistribution of water along the catena, as reported in similar toposequence studies (Omokaro, 2023 ; Okebalama et al., 2025 ). The corresponding decline in redox potential with increasing moisture is consistent with enhanced microbial respiration and oxygen consumption in organic-amended soils (Dorau et al., 2018). Greater reductions in Eh at the toeslope indicate prolonged moisture retention and reduced aeration, which support sustained microbial activity. These findings highlight the central role of hydro-redox conditions as regulators of soil biochemical functioning across landscape positions. Physiographic control of soil biochemical functioning The three physiographic positions established distinct hydrochemical environments that governed microbial processes, nutrient transformations, and plant nutrient acquisition. Baseline differences in moisture, pH, bulk density, and organic carbon created contrasting aeration regimes and redox conditions, which are key regulators of carbon and nutrient cycling in tropical soils (Bhanwaria et al., 2022 ). Crest soils, characterized by lower moisture and higher redox potential, favoured rapid oxygen diffusion but limited the persistence of microoxic zones necessary for sustained microbial activity (Dorau et al., 2018). In contrast, backslope and toeslope soils maintained higher moisture and lower redox potentials, supporting a broader spectrum of aerobic and facultative microbial metabolisms (Omokaro, 2023 ; Okebalama et al., 2025 ). These inherent differences conditioned the magnitude of soil and plant responses following compost application. Compost-induced modification of soil microhabitats Compost amendment enhanced both fungal and bacterial frequencies across all physiographic positions, reflecting increased substrate availability and improved microenvironmental conditions. The dominance of taxa such as Aspergillus, Penicillium, Cladosporium, Trichoderma, Rhizopus, Bacillus, Pseudomonas , and Streptomyces is consistent with known decomposer and plant growth-promoting groups in organic-amended soils (Chauhan et al., 2023 ). Compost contributed both nutrients and organic substrates, including labile and semi-labile carbon fractions, which stimulated microbial proliferation and metabolic activity (Li et al., 2021 ; Chen et al., 2023 ). The associated increase in soil moisture and organic colloids improved water-holding capacity and stabilized aggregates, promoting longer water residence times and reduced oxidative stress. These changes collectively lowered redox potential and enhanced microbial respiration (Liu et al., 2023 ; Rahman & Thomas, 2021 ). Toeslope soils consistently supported the highest microbial frequencies, reflecting favourable moisture and nutrient conditions (Borowik & Wyszkowska, 2016 ; Zhang et al., 2018 ). However, the relatively weak correlations between microbial frequency and plant growth variables indicate that microbial presence alone did not directly determine plant performance, but rather operated through functional pathways such as enzyme-mediated nutrient transformation and soil structural improvement. Environmentally mediated microbial-enzyme interactions Although microbial frequencies increased under compost amendment, enzyme activities showed stronger associations with soil moisture and redox conditions than with microbial occurrence. This indicates that enzyme expression was primarily regulated by microenvironmental conditions rather than by microbial frequency alone. Cellulase and protease activities increased progressively during crop growth, reflecting active decomposition of organic carbon and nitrogen substrates. These enzymes are central to carbon and nitrogen mineralization, and their enhancement under compost treatment is consistent with increased microbial metabolic activity in moisture-favourable environments (Zhang et al., 2018 ; Solangi et al., 2024 ). The strong positive relationships between enzyme activity and plant growth parameters indicate that enzyme-mediated nutrient release was a key driver of crop performance. Higher enzyme activities in backslope and toeslope soils further emphasize the importance of hydro-redox conditions in sustaining microbial functionality. Nutrient mineralization and vegetative growth responses Compost application significantly improved vegetative growth parameters of okra, including plant height, stem girth, leaf number, leaf area, and leaf area index, across all physiographic positions. These improvements are attributable to enhanced soil structure, increased moisture retention, and improved nutrient availability through microbial and enzymatic processes (Adewole & Ilesanmi, 2012 ; Nengi-Benwari & Abah, 2025 ). Growth responses followed the gradient toeslope > backslope > crest, reflecting topographic influences on soil moisture, aeration, and nutrient dynamics. Increased water availability at lower slope positions enhanced nutrient diffusion, microbial activity, and root physiological processes, consistent with findings by Belay et al. ( 2025 ) and Cai et al. ( 2025 ). Increased uptake of N, P, and K under compost amendment indicates efficient mineralization and nutrient release. Protease activity supports nitrogen mineralization, while cellulase activity contributes to carbon turnover that fuels microbial nutrient transformations. Improved pH buffering and increased exchangeable bases further enhanced nutrient retention and reduced phosphorus fixation, contributing to improved plant performance (Okole et al., 2025 ; Frimpong et al., 2017 ; Adekiya et al., 2020 ). Hydro-redox control of nutrient fluxes The inverse relationship between redox potential and nutrient uptake suggests that moderately reduced conditions supported nutrient mineralization and availability. While excessively low redox conditions may promote denitrification, the observed increases in total nitrogen and plant uptake indicate that mineralization processes dominated under the conditions of this study. The strong association between soil moisture and nutrient uptake highlights hydrological status as a key determinant of nutrient fluxes, reinforcing the coupling between moisture, redox dynamics, and nutrient mobility in slope-differentiated soils. Slope-dependent variation in compost effectiveness Although compost improved soil quality and plant performance across all positions, the magnitude of response varied significantly. Backslope and toeslope soils exhibited greater improvements due to favourable moisture and aeration regimes that enhanced microbial and enzymatic activity. Crest soils showed comparatively lower responses due to inherent hydrological limitations. These findings demonstrate that the effectiveness of organic amendments is strongly mediated by landscape position, and that uniform application rates may produce variable outcomes depending on slope-controlled soil processes. Limitations and future directions While the study provides strong empirical evidence of physiographic control over compost-mediated soil processes, certain limitations should be acknowledged. Intermediate nutrient pools such as ammonium, nitrate, and soluble phosphorus were not directly quantified. Future studies incorporating soil solution monitoring, microbial functional gene analysis, and gaseous nitrogen flux measurements would enhance mechanistic resolution. Additionally, direct measurement of redox potential using electrode-based methods would further strengthen interpretation of hydro-redox dynamics. Contribution to knowledge This study demonstrates that the agronomic effectiveness of poultry manure-based compost is strongly mediated by physiographic controls on soil moisture, redox potential, and microbial functioning. The results reveal a coherent biogeochemical cascade linking compost application to microbial activity, enzyme expression, nutrient mineralization, and plant growth, with landscape position modulating each stage. These findings provide mechanistic evidence that site-specific organic amendment strategies are essential for optimizing nutrient use efficiency and crop productivity in tropical agroecosystems, reinforcing the importance of soil-plant-microbe interactions within heterogeneous landscapes (Battacharyya & Furtak, 2023; Wang et al., 2025 ). Conclusion and Recommendations This study demonstrates that poultry-manure-based compost significantly enhances soil biochemical functioning, nutrient dynamics, and okra performance across contrasting physiographic positions in a southern Guinea Savanna environment. Compost application improved soil moisture retention and modified redox conditions, which stimulated microbial activity, increased cellulase and protease expression, and enhanced nutrient mineralization. These processes resulted in increased uptake of nitrogen, phosphorus, and potassium, leading to improved vegetative growth. The magnitude of these responses was strongly influenced by physiographic position, with backslope and toeslope soils consistently outperforming crest soils due to more favourable hydro-redox conditions. Compost application also improved post-harvest soil fertility indicators, demonstrating its potential for sustained soil quality enhancement. The findings highlight the importance of integrating landscape variability into organic amendment strategies to optimize crop productivity and nutrient use efficiency in tropical systems. Recommendations include adjusting compost rates or irrigation at crests, integrating mulch or micro-catchments on drier slopes, monitoring soil moisture, redox potential, and enzyme activities, and promoting on-farm poultry manure composting for sustainable smallholder systems. Declarations Ethics approval and consent to participate This study did not involve human participants, huma data, or animals. All plant materials used in this study complied with relevant institutional, national, and international guidelines for plant research. The study involved cultivated crop species ( Abelmoschus esculentus L. Moench) and did not involve endangered or protected plant species. Plant materials were sourced from a certified agricultural input supplier registered with the Kwara State Ministry of Agriculture. The study did not involve collection of plant specimens from government-protected land, private farmland, or natural ecosystems requiring special permits. Soil Samples were collected from the University of Ilorin Teaching and Research Farm with Institutional approval for research purposes. No specific permits or licenses were required for the use of commercially cultivated okra seeds or soil sampling within the University research farm. All procedures complied with standard agronomic and environmental research regulations in Nigeria. Consent for publication Not applicable Availability of data and materials All data generated or analysed during this study are included in this manuscript. Additional information related to the datasets used and analysed during the current study is available from the corresponding author upon reasonable request. Clinical trial number Not applicable Competing interests The authors declare that there are no competing interests, financial or non-financial, that could have influenced the work reported in this manuscript. Funding This research received no external funding. 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Zhou Y, Taylor RJ, Boutton TW. (2021). Divergent patterns and spatial heterogeneity of soil nutrients in a complex and dynamic savanna landscape. J Geophys Research: Biogeosciences, 126, e2021JG006575. Additional Declarations No competing interests reported. Supplementary Files image1.png Graphical Abstract Cite Share Download PDF Status: Under Review Version 1 posted Reviews received at journal 15 May, 2026 Reviews received at journal 09 May, 2026 Reviewers agreed at journal 07 May, 2026 Reviewers agreed at journal 05 May, 2026 Reviewers invited by journal 05 May, 2026 Editor assigned by journal 05 May, 2026 Editor invited by journal 02 Apr, 2026 Submission checks completed at journal 30 Mar, 2026 First submitted to journal 30 Mar, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Ilorin","correspondingAuthor":false,"prefix":"","firstName":"Hammed","middleName":"Alabi","lastName":"Olasupo","suffix":""},{"id":638433620,"identity":"f75236c2-79f7-4184-8829-6d64aaa98cd4","order_by":5,"name":"Damilola Abigael Ikuoponiyi","email":"","orcid":"","institution":"University of Ilorin","correspondingAuthor":false,"prefix":"","firstName":"Damilola","middleName":"Abigael","lastName":"Ikuoponiyi","suffix":""}],"badges":[],"createdAt":"2026-03-24 16:38:27","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9214501/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9214501/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":109160763,"identity":"7ae09274-0dc5-49bc-b9f5-825ccdada98d","added_by":"auto","created_at":"2026-05-13 07:35:29","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":499258,"visible":true,"origin":"","legend":"\u003cp\u003eTemporal dynamics of fungal frequency in crest soils under compost treatments during okra growth\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eC = poultry-manure-based compost, 20 = applied at 20 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, 0, control 0 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, U = crest position, M = backslope position, L = toeslope position\u0026nbsp;\u003c/em\u003e\u003c/p\u003e","description":"","filename":"image2.png","url":"https://assets-eu.researchsquare.com/files/rs-9214501/v1/87fb2d4a40e0f1bc8c6965e4.png"},{"id":109204966,"identity":"cc5d0741-c8f3-4aec-98f1-52fd794d9ac8","added_by":"auto","created_at":"2026-05-13 15:03:02","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":617375,"visible":true,"origin":"","legend":"\u003cp\u003eTemporal dynamics of fungal frequency in backslope soils under compost treatments during okra growth\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eC = poultry-manure-based compost, 20 = applied at 20 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, 0, control 0 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, U = crest position, M = backslope position, L = toeslope position\u0026nbsp;\u003c/em\u003e\u003c/p\u003e","description":"","filename":"image3.png","url":"https://assets-eu.researchsquare.com/files/rs-9214501/v1/9a68f2fde3fd9eb59d972eac.png"},{"id":109205357,"identity":"a24a5109-9f83-455a-b693-dd19cc0ad5e8","added_by":"auto","created_at":"2026-05-13 15:04:24","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":589776,"visible":true,"origin":"","legend":"\u003cp\u003eTemporal dynamics of fungal frequency in toeslope soils under compost treatments during okra growth\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eC = poultry-manure-based compost, 20 = applied at 20 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, 0, control 0 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, U = crest position, M = backslope position, L = toeslope position\u003c/em\u003e\u003c/p\u003e","description":"","filename":"image4.png","url":"https://assets-eu.researchsquare.com/files/rs-9214501/v1/8a0213d5e1a65178e3e229e0.png"},{"id":109205247,"identity":"c6f625a1-60b9-43c0-9549-18245837ce76","added_by":"auto","created_at":"2026-05-13 15:03:53","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":536961,"visible":true,"origin":"","legend":"\u003cp\u003eTemporal dynamics of bacterial frequency in crest soils under compost treatments during okra growth\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eC = poultry-manure-based compost, 20 = applied at 20 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, 0, control 0 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, U = crest position, M = backslope position, L = toeslope position\u003c/em\u003e\u003c/p\u003e","description":"","filename":"image5.png","url":"https://assets-eu.researchsquare.com/files/rs-9214501/v1/6f52b96ffda0ebacc5511322.png"},{"id":109205248,"identity":"435e66a3-98a1-432e-8e9b-9946e0d165fb","added_by":"auto","created_at":"2026-05-13 15:03:53","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":529689,"visible":true,"origin":"","legend":"\u003cp\u003eTemporal dynamics of bacterial frequency in backslope soils under compost treatments during okra growth\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eC = poultry-manure-based compost, 20 = applied at 20 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, 0, control 0 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, U = crest position, M = backslope position, L = toeslope position\u003c/em\u003e\u003c/p\u003e","description":"","filename":"image6.png","url":"https://assets-eu.researchsquare.com/files/rs-9214501/v1/bb7721f55752eb84d270a46c.png"},{"id":109205243,"identity":"1c72f559-a701-4e7a-9681-8ff8b3a89992","added_by":"auto","created_at":"2026-05-13 15:03:52","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":576697,"visible":true,"origin":"","legend":"\u003cp\u003eTemporal dynamics of bacterial frequency in toeslope soils under compost treatments during okra growth\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eC = poultry-manure-based compost, 20 = applied at 20 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, 0, control 0 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, U = crest position, M = backslope position, L = toeslope position\u003c/em\u003e\u003c/p\u003e","description":"","filename":"image7.png","url":"https://assets-eu.researchsquare.com/files/rs-9214501/v1/3f8bef56a29a45458354e1e6.png"},{"id":109222244,"identity":"b483fcfd-9af4-45a8-ba0d-023393b7a0d0","added_by":"auto","created_at":"2026-05-13 21:06:23","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":347258,"visible":true,"origin":"","legend":"\u003cp\u003eCellulase activity across physiographic positions under compost treatments during okra growth\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eC = poultry-manure-based compost, 20 = applied at 20 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, 0, control 0 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, U = crest position, M = backslope position, L = toeslope position\u003c/em\u003e\u003c/p\u003e","description":"","filename":"image8.png","url":"https://assets-eu.researchsquare.com/files/rs-9214501/v1/5fe7885dbca16956a569c5cc.png"},{"id":109204826,"identity":"dce0e5f2-e690-422a-88cf-235839e762e9","added_by":"auto","created_at":"2026-05-13 15:02:28","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":348009,"visible":true,"origin":"","legend":"\u003cp\u003eProtease activity across physiographic positions under compost treatments during okra growth\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eC = poultry-manure-based compost, 20 = applied at 20 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, 0, control 0 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, U = crest position, M = backslope position, L = toeslope position\u003c/em\u003e\u003c/p\u003e","description":"","filename":"image9.png","url":"https://assets-eu.researchsquare.com/files/rs-9214501/v1/76a9661eebdc4ba6be95b517.png"},{"id":109205354,"identity":"b6f6fe19-257a-4838-9fd7-83e8839a9c25","added_by":"auto","created_at":"2026-05-13 15:04:24","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":309678,"visible":true,"origin":"","legend":"\u003cp\u003eTemporal variation in okra plant height across physiographic positions under compost treatments\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eC = poultry-manure-based compost, 20 = applied at 20 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, 0, control 0 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, U = crest position, M = backslope position, L = toeslope position\u003c/em\u003e\u003c/p\u003e","description":"","filename":"image10.png","url":"https://assets-eu.researchsquare.com/files/rs-9214501/v1/5ba05716841e6ec471a5117b.png"},{"id":109204958,"identity":"3aa7cb54-a193-489a-8f0d-bf866dab6a5a","added_by":"auto","created_at":"2026-05-13 15:03:00","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":333670,"visible":true,"origin":"","legend":"\u003cp\u003eTemporal variation in okra stem girth across physiographic positions under compost treatments\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eC = poultry-manure-based compost, 20 = applied at 20 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, 0, control 0 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, U = crest position, M = backslope position, L = toeslope position\u003c/em\u003e\u003c/p\u003e","description":"","filename":"image11.png","url":"https://assets-eu.researchsquare.com/files/rs-9214501/v1/9c73b94999c5a049f3487082.png"},{"id":109206040,"identity":"e9c0db1f-0787-4441-adc3-15291ff78341","added_by":"auto","created_at":"2026-05-13 15:10:45","extension":"png","order_by":11,"title":"Figure 11","display":"","copyAsset":false,"role":"figure","size":269414,"visible":true,"origin":"","legend":"\u003cp\u003eTemporal variation in okra number of leaves across physiographic positions under compost treatments\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eC = poultry-manure-based compost, 20 = applied at 20 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, 0, control 0 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, U = crest position, M = backslope position, L = toeslope position\u003c/em\u003e\u003c/p\u003e","description":"","filename":"image12.png","url":"https://assets-eu.researchsquare.com/files/rs-9214501/v1/d51bda4943c72aca3c3a7f74.png"},{"id":109160769,"identity":"8f25ac34-cd51-4070-b846-dc94d4e76c69","added_by":"auto","created_at":"2026-05-13 07:35:30","extension":"png","order_by":12,"title":"Figure 12","display":"","copyAsset":false,"role":"figure","size":229149,"visible":true,"origin":"","legend":"\u003cp\u003eTemporal variation in okra leaf area across physiographic positions under compost treatments\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eC = poultry-manure-based compost, 20 = applied at 20 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, 0, control 0 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, U = crest position, M = backslope position, L = toeslope position\u003c/em\u003e\u003c/p\u003e","description":"","filename":"image13.png","url":"https://assets-eu.researchsquare.com/files/rs-9214501/v1/7edf193ca23b1e73f3106727.png"},{"id":109160767,"identity":"d8eca629-5713-4733-95b3-8fc5e2fe33b5","added_by":"auto","created_at":"2026-05-13 07:35:29","extension":"png","order_by":13,"title":"Figure 13","display":"","copyAsset":false,"role":"figure","size":254583,"visible":true,"origin":"","legend":"\u003cp\u003eTemporal variation in okra leaf area index across physiographic positions under compost treatments\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eC = poultry-manure-based compost, 20 = applied at 20 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, 0, control 0 t ha\u003c/em\u003e\u003csup\u003e\u003cem\u003e-1\u003c/em\u003e\u003c/sup\u003e\u003cem\u003e, U = crest position, M = backslope position, L = toeslope position\u003c/em\u003e\u003c/p\u003e","description":"","filename":"image14.png","url":"https://assets-eu.researchsquare.com/files/rs-9214501/v1/a49a2c9693d2e41af86a5d43.png"},{"id":109296019,"identity":"55155e0a-0cca-4469-ac5d-ca91366ee11d","added_by":"auto","created_at":"2026-05-15 08:44:21","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":6148194,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9214501/v1/427be584-ed1c-41dd-9938-bdbc0fc296a2.pdf"},{"id":109204965,"identity":"963f8650-ca27-421d-b59a-c46298ad0d1b","added_by":"auto","created_at":"2026-05-13 15:03:02","extension":"png","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":2450169,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003eGraphical Abstract\u003c/em\u003e\u003c/p\u003e","description":"","filename":"image1.png","url":"https://assets-eu.researchsquare.com/files/rs-9214501/v1/9b1416720b80bb86b4b64c58.png"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003ePhysiographic Modulation of Soil Hydro-redox Conditions and Compost-induced Microbial Dynamics, Enzyme Activity, Nutrient Uptake in Okra\u003c/p\u003e","fulltext":[{"header":"Highlights","content":"\u003col style=\"list-style-type: lower-roman;\"\u003e\n \u003cli\u003ePhysiographic position strongly regulates compost effectiveness in tropical soils\u003c/li\u003e\n \u003cli\u003eSoil moisture and redox conditions drive enzyme-mediated nutrient mineralization\u003c/li\u003e\n \u003cli\u003eEnzyme activity, not microbial frequency, predicts nutrient uptake and plant growth\u003c/li\u003e\n \u003cli\u003eCompost effects follow a consistent gradient: toeslope \u0026gt; backslope \u0026gt; crest\u003c/li\u003e\n \u003cli\u003eLandscape-specific compost management improves nutrient use efficiency\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Introduction","content":"\u003cp\u003eOrganic amendments are critical tools for improving soil fertility, enhancing nutrient cycling, and promoting sustainable crop productivity in tropical agroecosystems (Zhou et al., \u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Yang et al., \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Poultry-manure-based compost, in particular, provides a rich source of organic carbon, nitrogen, and micronutrients, while simultaneously acting as a microbial inoculum to stimulate soil biological activity (Adewole \u0026amp; Ilesanmi, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2012\u003c/span\u003e; Nengi-Benwari \u0026amp; Abah, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2025\u003c/span\u003e). Despite widespread adoption, the agronomic effectiveness of compost is often uneven, with crop response varying according to soil properties, landscape position, and microenvironmental conditions (Belay et al., \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2025\u003c/span\u003e; Cai et al., \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2025\u003c/span\u003e). Soil physiography strongly influences hydrological dynamics, redox potential, and microbial processes along slope positions (Bufebo et al., \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Suvendran et al., \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e2025\u003c/span\u003e). Crest soils tend to be drier and more oxidized, limiting sustained microoxic zones, whereas backslope and toeslope soils retain higher moisture and exhibit lower redox potentials, creating favorable conditions for microbial proliferation and enzymatic activity (Dorau et al., 2018; Omokaro, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Okebalama et al., \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2025\u003c/span\u003e). These differences establish distinct soil microenvironments that regulate nutrient mineralization, substrate availability, and plant nutrient acquisition (Bhanwaria et al., \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). The role of physiographic heterogeneity in shaping the effectiveness of organic amendments remains poorly quantified in tropical cropping systems.\u003c/p\u003e \u003cp\u003eCompost maturation dynamics directly influence soil biochemical functioning. Thermophilic decomposition of labile carbon fractions, progressive mineralization of nitrogen, and stabilization of heavy metals collectively determine compost stability, nutrient release patterns, and environmental safety (Papale et al., \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Wang et al., \u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Jakubus, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; Ouali et al., \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2025\u003c/span\u003e; Okoro et al., \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2025\u003c/span\u003e). Incorporation of mature compost into soil not only contributes nutrients but also modifies soil structure, enhances water retention, and facilitates microbial colonization. Increased water-holding capacity and stabilized soil aggregates extend moisture residence times, moderate redox fluctuations, and improve conditions for both fungal and bacterial growth (Li et al., \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Chen et al., \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Xu et al., \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Microbial-enzyme interactions are central to nutrient mineralization in amended soils. Fungal taxa such as \u003cem\u003eAspergillus, Trichoderma\u003c/em\u003e, and \u003cem\u003eCladosporium\u003c/em\u003e efficiently decompose complex substrates, while bacterial genera including \u003cem\u003eBacillus, Pseudomonas\u003c/em\u003e, and \u003cem\u003eStreptomyces\u003c/em\u003e solubilize nutrients and promote plant growth (Chauhan et al., \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Chen et al., \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Enzymes such as cellulase and protease serve as functional indicators of carbon and nitrogen turnover, with their activities strongly influenced by soil moisture and redox potential (Zhang et al., \u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Tamura \u0026amp; Suseela, \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Solangi et al., \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). Moderate declines in redox potential promote microoxic zones that enhance enzyme stability, facilitate substrate diffusion, and support facultative microbial metabolisms (Liu et al., \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Rahman \u0026amp; Thomas, \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2021\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe interaction between landscape position, moisture, and redox potential further modulates nutrient availability and plant uptake. Toposequence-driven differences in microclimate create spatial variability in microbial and enzymatic responses, resulting in differential nitrogen, phosphorus, and potassium availability for crops such as okra (Borowik \u0026amp; Wyszkowska, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2016\u003c/span\u003e; Zhang et al., \u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Bufebo et al., \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Bogati et al., \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2025\u003c/span\u003e). Positive associations between microbial enzyme activities and nutrient uptake indicate that compost-mediated nutrient transformations are a key driver of improved plant performance, emphasizing the importance of integrating hydrological and biochemical controls into organic amendment strategies (Chen et al., \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Bogati et al., \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2025\u003c/span\u003e). Despite the recognized benefits of compost, previous studies often overlook the mechanistic cascade linking amendment, microbial proliferation, enzymatic activity, nutrient mineralization, and plant growth across contrasting physiographic positions (Guo et al., \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Bogati et al., \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Wang et al., \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Furthermore, intermediate nutrient pools, such as ammonium, nitrate, and soluble phosphorus, are rarely quantified in situ, limiting mechanistic understanding. Comprehensive assessments that couple soil moisture, redox potential, microbial-enzyme interactions, and crop performance are therefore essential to optimize compost management in heterogeneous landscapes (Frimpong et al., \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2017\u003c/span\u003e; Adekiya et al., \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; Ahmed et al., \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Huang et al., \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2025\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThis study hypothesizes that poultry-manure-based compost enhances microbial-enzyme activity, nutrient mineralization, and okra growth, with the magnitude of these effects modulated by physiographic position. Specifically, we evaluate (i) compost maturation dynamics and their nutrient and heavy metal profiles; (ii) soil microenvironmental changes (moisture, redox, physicochemical properties) following amendment; (iii) microbial frequency, enzyme activity, and nutrient mineralization patterns along a toposequence; and (iv) correlations between soil biochemical processes and okra vegetative performance. Findings from this work aim to provide mechanistic evidence for site-specific organic amendment strategies that optimize nutrient use efficiency and crop productivity in tropical smallholder farming systems.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy area and soil sampling\u003c/h2\u003e \u003cp\u003eThe study was carried out in the screenhouse of the Department of Agronomy, Faculty of Agriculture, University of Ilorin, Nigeria (8\u0026ordm;29\u0026prime; N, 4\u0026ordm;40\u0026prime; E; 307 m above sea level). The location lies within the southern Guinea savanna agroecological zone. The region is characterized by tropical climate with distinct wet and dry seasons and an average annual rainfall of approximately 1200 mm.\u003c/p\u003e \u003cp\u003eSurface soils (0\u0026ndash;20 cm) were collected from three distinct physiographic positions within the University of Ilorin Teaching and Research Farm: crest (8\u0026ordm;29\u0026prime;35\u0026Prime; N, 4\u0026ordm;39\u0026prime;55\u0026Prime; E) for the crest, backslope (8\u0026ordm;29\u0026prime;28\u0026Prime; N, 4\u0026ordm;40\u0026prime;05\u0026Prime; E) and toeslope (8\u0026ordm;29\u0026prime;22\u0026Prime; N, 4\u0026ordm;40\u0026prime;13\u0026Prime; E). At each position, five subsamples were randomly collected along a 50 m transect using a soil auger, composited, air-dried, gently crushed, and sieved through a 2 mm mesh. The processed soils were stored in labelled polythene bags prior to use. Baseline physicochemical properties of the soils were determined using standard procedures (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eBaseline physicochemical properties of soils across crest, backslope, and toeslope positions before compost application\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"12\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSampling points\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMoisture\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003epH\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eBulk Density\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eOrganic C\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eTotal N\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAvailable P\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eC/N ratio\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003eK\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c10\"\u003e \u003cp\u003eCa\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c11\"\u003e \u003cp\u003eMg\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c12\"\u003e \u003cp\u003eNa\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e(%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(kg m\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c7\" namest=\"c5\"\u003e \u003cp\u003e(mg kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c12\" namest=\"c9\"\u003e \u003cp\u003e(cmol kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCrest\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e8.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1520\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e15000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1200\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e12.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e4.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e1.15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e0.13\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBackslope\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e12.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1310\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e18500\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1500\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e12.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e6.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e1.65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e0.20\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eToeslope\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e18.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1030\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e22000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1900\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e11.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e8.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e2.30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e0.26\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLSD (P\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e8.87\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e74.25\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e18.13\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e18.11\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e15.12\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e12.16\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003e74.75\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e\u003cb\u003e10.31\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e\u003cb\u003e11.23\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e\u003cb\u003e10.19\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e10.39\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"12\"\u003e*** = significance at P\u0026thinsp;\u0026le;\u0026thinsp;0.001\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003ePoultry manure-based compost production and characterization\u003c/h3\u003e\n\u003cp\u003eCompost was produced using poultry manure and selected crop residues through twelve weeks of aerobic decomposition. Poultry manure (\u0026lt;\u0026thinsp;24 hours old) and grass clippings were collected from the University of Ilorin Teaching and Research Farm, while rice bran, sawdust, and cassava peels were sourced from major markets within Ilorin. Rice bran was collected from Oja Gboro Market, sawdust from Irewolede sawmill, and cassava peels from the General Market. All materials were collected in clean, labelled polyethylene bags and transported to the laboratory. Each residue was weighed and ground using a mechanical grinder to enhance microbial colonization and uniform mixing.\u003c/p\u003e \u003cp\u003eA cylindrical pit measuring 50 cm \u0026times; 100 cm was dug at the composting site. A perforated dark plastic bucket was placed centrally within the pit to promote passive aeration and temperature retention. The feedstocks were mixed and arranged in alternating layers inside the composting bucket at a ratio of 1:5 (w/w) corresponding to 16.67% poultry manure and 83.33% plant residues. A base layer of 1 kg of poultry manure was placed in the bucket and covered with 5 kg of sawdust. Additional layers were added in the following sequence: 1 kg of poultry manure covered with 5 kg of grass clippings, followed by another 1 kg of poultry manure covered with 5 kg of shredded cassava peels, and another 1 kg of poultry manure covered with 5 kg of rice husk. Layering continued until all materials were exhausted. The space between the basket and the walls of the pit was filled with sawdust to provide insulation.\u003c/p\u003e \u003cp\u003eThe composting mass was lightly moistened to achieve approximately 60% field capacity and maintained throughout the period by intermittent application of clean water using a calibrated 1-liter container. Additional wetting with approximately 0.5 litres was done whenever the pile showed signs of dehydration. The buckets were covered with a black plastic bag to conserve heat and minimize evaporation. Aeration was enhanced by manually turning the compost every two days during the first two weeks and every seven days thereafter, using a disinfected wooden paddle.\u003c/p\u003e \u003cp\u003eTemperature was monitored biweekly using a calibrated soil thermometer, which was inserted for five minutes before reading. Compost subsamples were taken at weeks 0, 2, 4, 6, 8, 10, and 12 for physicochemical assessment. Organic carbon was determined by the Walkley-Black method. Total nitrogen was determined by the Kjeldahl digestion method. Available phosphorus was quantified using the Bray 1 extractant. Exchangeable cations (K, Ca, Mg, and Na) were extracted using 1 M ammonium acetate and analysed by flame photometry (K, Na) and atomic absorption spectrophotometry (Ca, Mg). Heavy metals (Zn, Pb, Cd, Cr, Cu, and Ni) were analysed using atomic absorption spectrophotometry following wet digestion. Moisture content was determined gravimetrically, and pH was measured in a 1:2.5 compost-to-water suspension.\u003c/p\u003e \u003cp\u003eAt week 12, the matured compost was air-dried, sieved (2 mm), and analysed for proximate composition. Moisture, ash, protein, fat, and crude fibre were determined according to AOAC (2004). Carbohydrates were computed by difference following FAO (2004):\u003cdiv id=\"Equa\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equa\" name=\"EquationSource\"\u003e\n$$\\:\\%Carbohydrate=100-\\:\\left(\\%Moisture+\\%Ash+\\%Protein+\\%Fat\\right)$$\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eThe physicochemical properties of the feedstocks and the temporal changes in compost properties, heavy metal concentrations, and exchangeable bases are presented in Tables\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, \u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, \u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e, and \u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePhysicochemical characteristics of compost feedstocks used in formulation\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"13\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c13\" colnum=\"13\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eParameters\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMoisture\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003epH\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eBulk Density\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eOrganic C\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eTotal N\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAsh\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eC/N ratio\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003eAvailable P\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c10\"\u003e \u003cp\u003eK\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c11\"\u003e \u003cp\u003eCa\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c12\"\u003e \u003cp\u003eMg\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c13\"\u003e \u003cp\u003eNa\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e(%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(kg m\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c7\" namest=\"c5\"\u003e \u003cp\u003emg kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"5\" nameend=\"c13\" namest=\"c9\"\u003e \u003cp\u003ecmol kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePoultry Manure\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e70.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e7.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e550\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e380000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e26500\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e250000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e14.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e4800\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e12.28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e107.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e289.30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e36.52\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCassava Peels\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e68.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e5.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e420\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e410000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e9200\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e60000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e44.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e2300\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e5.88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e79.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e78.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e20.43\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSaw Dust\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e55.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e5.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e310\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e465000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e20000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e221.43\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e900\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e2.30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e17.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e34.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e6.96\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRice Bran\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e64.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e380\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e395000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e11800\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e100000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e33.47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e2700\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e6.90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e91.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e119.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e26.96\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGrass Clippings\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e73.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e290\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e360000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e17200\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e120000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e20.93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e3100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e7.93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e98.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e105.36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e22.17\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLSD (P\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e39.96\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e37.79\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e15.73\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e42.27\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e6.12\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e5.28\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003e3.21\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u003cb\u003e8.19\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e\u003cb\u003e9.21\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c11\"\u003e \u003cp\u003e\u003cb\u003e5.40\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c12\"\u003e \u003cp\u003e\u003cb\u003e8.80\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c13\"\u003e \u003cp\u003e6.31\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"13\"\u003e*** = significance at P\u0026thinsp;\u0026le;\u0026thinsp;0.001\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eTemporal variation in physicochemical properties of composting materials during aerobic decomposition (0\u0026ndash;12 weeks)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTime\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTemperature\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003epH\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMoisture content\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eTotal N\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eTotal OC\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAvailable P\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eC/N ratio\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e(week)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e(\u003csup\u003eo\u003c/sup\u003eC)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c7\" namest=\"c5\"\u003e \u003cp\u003emg kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e28.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6.80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e55.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1480\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e25800\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e450\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e17.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e68.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e7.52\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e35.70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1580\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e23600\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e520\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e14.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e62.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e7.21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e34.31\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1830\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e21400\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e610\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e11.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e48.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e7.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e33.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1950\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e19800\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e700\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e10.2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e39.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e7.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e31.90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2010\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e18200\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e780\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e9.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e33.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6.95\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e30.80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2070\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e16700\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e840\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e8.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e29.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e29.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2120\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e13500\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e900\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e6.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003et-stat (p\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e13.20\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e137.19\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e19.76\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e36.44\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e22.94\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e13.71\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e19.82\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"8\"\u003e*** = significance at P\u0026thinsp;\u0026le;\u0026thinsp;0.001\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eTemporal changes in heavy metal concentrations and exchangeable base cations during composting (0\u0026ndash;12 weeks)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"12\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTime\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"7\" nameend=\"c8\" namest=\"c2\"\u003e \u003cp\u003eHeavy Metal Reduction\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c12\" namest=\"c9\"\u003e \u003cp\u003eExchangeable bases\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e(week)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"7\" nameend=\"c8\" namest=\"c2\"\u003e \u003cp\u003e(mg kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c12\" namest=\"c9\"\u003e \u003cp\u003e(cmol kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eZn\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePb\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eCd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eCr\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eCu\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eNi\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003eCa\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eMg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eK\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eNa\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e145\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e118\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003e12.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e4.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e2.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e132\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e110\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003e13.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e4.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e3.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e120\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e49\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e101\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003e14.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e4.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e4.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e109\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e43\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003e15.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e5.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e4.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.9\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003e15.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e5.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e4.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e1.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e89\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003e16.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e5.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e5.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e1.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003e16.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e5.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e5.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e1.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLSD (P\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e23.24\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e18.37\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e18.30\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e23.02\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e29.55\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e19.89\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003e\u003cb\u003e47.54\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e\u003cb\u003e39.29\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e\u003cb\u003e23.10\u003c/b\u003e\u003csup\u003e\u003cb\u003e***\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e22.94\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"12\"\u003e*** = significance at P\u0026thinsp;\u0026le;\u0026thinsp;0.001\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eProximate composition of matured compost at week 12 (wet basis)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eParameters\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e% Composition (w/w)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eLSD (P\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMoisture\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e32.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1108.51\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAsh\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e866.03\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eProtein\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e76.79\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFat\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e108.25\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCrude fibre\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e16.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e923.76\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCarbohydrates\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e23.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1337.72\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"3\"\u003e*** = significance at P\u0026thinsp;\u0026le;\u0026thinsp;0.001\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e\n\u003ch3\u003ePlant materials and source\u003c/h3\u003e\n\u003cp\u003eSeeds of okra (\u003cem\u003eAbelmoschus esculentus\u003c/em\u003e L. Moench., variety Clemson Spineless) used in this study were obtained from a certified agricultural input supplier in Ilorin, Kwara State, Nigeria. The seeds are commercially cultivated and widely distributed for agricultural puproses. All experimental soils were collected from the University of Ilorin Teaching and Research Farm, located at crest (8\u0026ordm;29\u0026prime;35\u0026Prime; N, 4\u0026ordm;39\u0026prime;55\u0026Prime; E), backslope (8\u0026ordm;29\u0026prime;28\u0026Prime; N, 4\u0026ordm;40\u0026prime;05\u0026Prime; E) and toeslope (8\u0026ordm;29\u0026prime;22\u0026Prime; N, 4\u0026ordm;40\u0026prime;13\u0026Prime; E) positions.\u003c/p\u003e \u003cp\u003eNo wild plant species were collected from natural ecosystems for this study. The okra plants used in the experiment were cultivated entirely under controlled screenhouse conditions.\u003c/p\u003e\n\u003ch3\u003eExperimental design and setup\u003c/h3\u003e\n\u003cp\u003eThe experiment followed a 3 \u0026times; 2 factorial arrangement in a completely randomized design. The factors were physiographic position (crest, backslope, and toeslope) and compost level (0 and 20 t ha⁻\u0026sup1;). Each treatment combination was replicated three times, resulting in a total of 18 pots. Plastic pots (15 cm diameter) were filled with 5 kg of sieved soil. Compost was incorporated into the top 10 cm layer of soil in the amended pots at the equivalent rate of 20 t ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. The amended and control soils were pre-incubated for two weeks to allow microbial and chemical stabilization. No mineral fertilizer was applied. Seeds of okra (\u003cem\u003eAbelmoschus esculentus\u003c/em\u003e L. Moench., variety Clemson Spineless) were sown directly into the pots at three seeds per hole and later thinned to one healthy seedling per pot. All pots were irrigated daily to maintain field capacity. Vegetative growth parameters, including plant height, stem girth, number of leaves, leaf length, and leaf width, were recorded at 2-week intervals (2, 4, 6, and 8 weeks after planting). Leaf area and leaf area index were computed using standard agronomic formulae.\u003c/p\u003e\n\u003ch3\u003eEmpirical estimation of soil redox potential\u003c/h3\u003e\n\u003cp\u003eSoil redox potential (Eh) was not directly measured using platinum electrodes in this study. Instead, Eh values were estimated empirically from soil moisture content using site-specific regression models. Empirical prediction of Eh from moisture or water-filled pore space has been applied in ecological and soil biogeochemical studies where direct electrode measurements are unavailable (Patrick \u0026amp; Reddy, 1978; Husson, 2013; Khan \u0026amp; Hossain, 2020).\u003c/p\u003e \u003cp\u003eGiven the well-established inverse relationship between soil aeration and moisture content, separate linear models were fitted for each physiographic position (crest, backslope, toeslope), incorporating soil moisture and compost level as predictors (Masschelyleyn et al., 1991; Reddy \u0026amp; DeLaune, \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2008\u003c/span\u003e). Compost was coded as 0 (control) or 1 (20 t ha⁻\u0026sup1;).\u003c/p\u003e \u003cp\u003eThe general model was:\u003cdiv id=\"Equb\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equb\" name=\"EquationSource\"\u003e\n$$\\:Eh\\:\\left(mV\\right)\\:=a-b\\:\\left(moisture\\right)+c\\left(compost\\right)$$\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003ewas fitted using ordinary least squares (OLS) for each slope position. Compost was coded as 0 (control) or 1 (20 t ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e).\u003c/p\u003e \u003cp\u003ewhere Eh represents estimated redox potential (mV), a is the intercept, b represents the rate of Eh decline per unit increase in soil moisture, and c represents the compost-induced redox adjustment factor.\u003c/p\u003e \u003cp\u003eThese models provide relative comparisons of redox dynamics across slope positions but should be interpreted as predictive approximations rather than direct electrochemical measurements. Consequently, associations between Eh and other variables should be interpreted within the context of model-derived estimation rather than independently measured redox potential. The moisture content and Eh values for the three physiographic positions are shown in Table\u0026nbsp;\u003cspan refid=\"Tab6\" class=\"InternalRef\"\u003e6\u003c/span\u003e.\u003c/p\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eNutrient uptake and post-harvest soil analysis\u003c/h2\u003e \u003cp\u003ePlants were harvested at eight weeks after sowing. Shoots and roots were washed with distilled water, oven-dried at 65\u0026deg;C to a constant weight, and then ground. Total nitrogen was determined by the Kjeldahl method (Bremner, 1965), phosphorus by the molybdenum blue method (Murphy \u0026amp; Riley, 1962), and potassium by flame photometry (Black, 1965). Nutrient uptake was calculated as:\u003cdiv id=\"Equc\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equc\" name=\"EquationSource\"\u003e\n$$\\:Uptake\\:\\left({mg\\:plant}^{-1}\\right)\\:=Dry\\:matter\\:\\left({g\\:plant}^{-1}\\right)\\:\\times\\:Nutrient\\:concentration\\:\\left({mg\\:g}^{-1}\\right)$$\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eThe results of nutrient uptake are presented in Table\u0026nbsp;\u003cspan refid=\"Tab7\" class=\"InternalRef\"\u003e7\u003c/span\u003e.\u003c/p\u003e \u003cp\u003ePost-harvest soils were sampled, air-dried, sieved (2 mm), and analyzed for pH (1:2.5 soil: water), organic carbon (Walkley-Black method), total nitrogen (Kjeldahl method), available phosphorus (Bray-1 method), and exchangeable potassium (1 N ammonium acetate extraction). The results are shown in Table\u0026nbsp;\u003cspan refid=\"Tab8\" class=\"InternalRef\"\u003e8\u003c/span\u003e.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eMicrobial frequency and enzyme activity assays\u003c/h3\u003e\n\u003cp\u003eSoil samples collected at 0, 2, 4, 6, and 8 weeks after compost application were used to determine microbial population and enzyme activities. Serial dilutions were prepared to 10\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e and 10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e for bacteria and fungi. Bacteria were isolated on nutrient agar and incubated at 35\u0026thinsp;\u0026plusmn;\u0026thinsp;2 \u003csup\u003eo\u003c/sup\u003eC for 24 to 48 hours. Fungi were isolated on potato dextrose agar amended with streptomycin (100 mg/L) and incubated at 28\u0026thinsp;\u0026plusmn;\u0026thinsp;2\u0026deg;C for 72 to 120 hours. Distinct colonies were purified through subculturing and identified by their cultural, biochemical, and microscopic characteristics.\u003c/p\u003e \u003cp\u003eThe percentage frequency of occurrence was calculated as:\u003cdiv id=\"Equd\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equd\" name=\"EquationSource\"\u003e\n$$\\:Frequency\\:\\left(\\:\\%\\right)\\:=\\:\\frac{Number\\:of\\:isolates\\:of\\:a\\:species}{Total\\:isolates\\:recovered}\\times\\:100$$\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eFungal and bacterial frequency distributions across physiographic positions are presented in Figs.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e and \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e, respectively.\u003c/p\u003e \u003cp\u003eEnzyme assays were performed using the same soil samples as described by Tabatabai (1994) and Alef and Nannipieri (1995). Cellulase activity was determined as the rate of reducing sugar formation (\u0026micro;mol glucose g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e soil h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) by the dinitrosalicylic acid method, and protease activity as the rate of tyrosine release from casein (\u0026micro;mol tyrosine g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e soil h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e). The results are presented in Figs.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e and \u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003e.\u003c/p\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eData were subjected to factorial analysis consistent with the 3 \u0026times; 2 experimental designs (physiographic position \u0026times; compost level). Treatment effects and their interactions were evaluated using two-way analysis of variance (ANOVA). Where significant main or interaction effects were detected, means were separated using the Least Significant Difference (LSD) test at P\u0026thinsp;\u0026le;\u0026thinsp;0.05. Temporal data (0\u0026ndash;8 weeks) were analyzed considering sampling time as a repeated factor to account for within-treatment dependence. Pearson correlation coefficients were computed to evaluate associations among soil moisture, estimated redox potential, microbial frequency, enzyme activity, nutrient uptake, and vegetative growth parameters. Because redox potential was derived from moisture-based regression models, interpretation of correlations involving Eh was made cautiously to avoid circular inference.\u003c/p\u003e \u003cp\u003eAll analyses were performed using GenStat version 12 (VSN International, UK), and graphical outputs were generated using GraphPad Prism.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\n \u003ch2\u003eBaseline soil physicochemical properties across physiographic positions\u003c/h2\u003e\n \u003cp\u003eBaseline soil properties differed significantly across the crest, backslope, and toeslope positions (Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e). A clear downslope gradient was observed, with higher moisture, organic carbon, total nitrogen, and exchangeable bases in the toeslope compared with the crest. Bulk density decreased downslope, indicating improved soil structure in lower landscape positions. Overall, the toeslope exhibited the most favorable initial conditions for biological activity and nutrient availability, while the crest represented a comparatively drier and nutrient-limited environment.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\n \u003ch2\u003ePhysicochemical properties of compost feedstocks\u003c/h2\u003e\n \u003cp\u003eThe compost feedstocks showed wide variability in physicochemical properties (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e), with poultry manure contributing the highest nutrient concentrations and lowest C:N ratio, while sawdust exhibited high carbon content and low nutrient levels. These contrasting properties ensured a balanced substrate composition necessary for effective composting.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e\n \u003ch2\u003eCompost physicochemical dynamics during aerobic decomposition\u003c/h2\u003e\n \u003cp\u003eComposting followed a typical thermophilic pattern, with temperature peaking at Week 2 and declining thereafter (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e). Organic carbon decreased while total nitrogen and available phosphorus increased, resulting in a marked reduction in C:N ratio, indicating progressive stabilization and maturity of the compost. Moisture content declined steadily over time, reflecting evaporation and microbial utilization.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e\n \u003ch2\u003eHeavy metal concentration and exchangeable base trends during composting\u003c/h2\u003e\n \u003cp\u003eHeavy metal concentrations declined during composting (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e). These decreases likely reflect dilution, immobilization, and complexation processes rather than true elemental loss. In contrast, exchangeable Ca, Mg, K, and Na increased progressively, indicating mineral enrichment and improved nutrient availability in the matured compost.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec16\" class=\"Section2\"\u003e\n \u003ch2\u003eProximate composition of mature compost\u003c/h2\u003e\n \u003cp\u003eThe proximate composition of the mature compost at Week 12 (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e) showed moisture content of 32%, ash content of 25%, protein 1.33%, fat 2.50%, crude fibre 16%, and carbohydrate 23.17%. All parameters differed significantly from their initial values or expected means (t\u0026thinsp;=\u0026thinsp;76.79\u0026ndash;1337.72; p\u0026thinsp;\u0026le;\u0026thinsp;0.001).\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec17\" class=\"Section2\"\u003e\n \u003ch2\u003eSoil microenvironmental response to compost application\u003c/h2\u003e\n \u003cp\u003eSoil moisture increased over time and was consistently higher in compost-amended soils across all physiographic positions (Table \u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e). A clear gradient of toeslope\u0026thinsp;\u0026gt;\u0026thinsp;backslope\u0026thinsp;\u0026gt;\u0026thinsp;crest was maintained throughout the study. Estimated redox potential (Eh) showed an inverse relationship with moisture and declined over time, with lower values observed in compost-treated soils and in lower slope positions. Soil moisture increased progressively over time in both treatments and across all physiographic positions, with consistently higher values under compost amendment. Correspondingly, Eh declined with increasing moisture, and remained lower in compost-amended soils than in control across all sampling periods.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003ctable id=\"Tab6\" border=\"1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 6\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eSoil moisture content (%) and redox potential (Eh, mV) across physiographic positions under compost treatments during 8 weeks of okra growth\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eTime\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eCompost level\u003c/p\u003e\n \u003c/th\u003e\n \u003cth colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eCrest\u003c/p\u003e\n \u003c/th\u003e\n \u003cth colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eBackslope\u003c/p\u003e\n \u003c/th\u003e\n \u003cth colspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eToeslope\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMoisture\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eEh\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMoisture\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eEh\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMoisture\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eEh\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e(week)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e(t ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e(%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e(%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e(%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emV\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eControl (0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e522.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e18.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e488.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e22.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e434.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17.20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e514.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e476.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e24.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e425.67\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eControl (0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e16.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e511.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e19.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e472.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e23.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e421.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e18.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e498.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e21.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e455.67\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e409.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eControl (0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e496.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20.57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e461.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e23.90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e405.67\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e19.60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e472.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e22.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e436.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e26.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e396.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eControl (0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17.77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e478.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e21.20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e448.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e24.67\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e392.33\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e455.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e23.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e422.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e27.20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e384.33\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eControl (0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e18.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e465.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e21.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e438.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e379.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e449.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e23.60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e414.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e27.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e371.33\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLSD (P\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e64.04\u003c/strong\u003e\u003csup\u003e\u003cstrong\u003e***\u003c/strong\u003e\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e106.94\u003c/strong\u003e\u003csup\u003e\u003cstrong\u003e***\u003c/strong\u003e\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e77.96\u003c/strong\u003e\u003csup\u003e\u003cstrong\u003e***\u003c/strong\u003e\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e106.94\u003c/strong\u003e\u003csup\u003e\u003cstrong\u003e***\u003c/strong\u003e\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e81.12\u003c/strong\u003e\u003csup\u003e\u003cstrong\u003e***\u003c/strong\u003e\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e109.01\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"8\"\u003e*** = significance at P\u0026thinsp;\u0026le;\u0026thinsp;0.001\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec18\" class=\"Section2\"\u003e\n \u003ch2\u003eMicrobial population dynamics across physiographic positions\u003c/h2\u003e\n \u003cp\u003eFungal frequencies increased progressively over time in all slope positions and were consistently higher under compost amendment (Figs.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e). Compost amendment consistently increased the frequency of all fungal taxa relative to the control. Toeslope soils recorded the highest frequencies, followed by backslope and crest soils. At the crest (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e), \u003cem\u003eAspergillus niger, Penicillium chrysogenum, Cladosporium spp., Trichoderma viridae\u003c/em\u003e, and \u003cem\u003eRhizopus spp.\u003c/em\u003e increased gradually with time. The backslope (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e) exhibited steeper increases, with \u003cem\u003eA. flavus\u003c/em\u003e showing pronounced elevation under compost amendment. The toeslope (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e) showed the highest fungal proliferation, with compost consistently producing greater frequencies.\u003c/p\u003e\n \u003cp\u003eBacterial frequencies followed similar trends (Figs.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e). Compost significantly increased the occurrence of bacteria across all positions. In the crest soils, taxa such as \u003cem\u003eBacillus spp., Micrococcus spp., Arthrobacter spp., and Pseudomonas spp\u003c/em\u003e. exhibited modest increases under the control but showed substantially higher frequencies under compost (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e). At the backslope, compost application resulted in more pronounced increases in \u003cem\u003eBacillus, Pseudomonas, Enterobacter, Streptomyces\u003c/em\u003e, and \u003cem\u003ePaenibacillus\u003c/em\u003e compared to the crest position (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e). In the toeslope soils, all bacterial groups displayed the highest overall frequencies, with compost producing a strong and consistent upward trajectory for \u003cem\u003ePseudomonas, Bacillus, Enterobacter, Streptomyces, and Paenibacillus\u003c/em\u003e across sampling times (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e). As with fungi, bacterial frequency patterns followed the hierarchy toeslope\u0026thinsp;\u0026gt;\u0026thinsp;backslope\u0026thinsp;\u0026gt;\u0026thinsp;crest, with compost consistently amplifying frequencies relative to the controls.\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec19\" class=\"Section2\"\u003e\n \u003ch2\u003eSoil enzyme activities\u003c/h2\u003e\n \u003cp\u003eCellulase and protease activities increased with time and were consistently higher in compost-amended soils (Figs.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e7\u003c/span\u003e and \u003cspan class=\"InternalRef\"\u003e8\u003c/span\u003e). Activities were greatest in the toeslope, followed by backslope and crest positions. This pattern mirrors moisture availability and suggests strong environmental regulation of enzyme expression.\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec20\" class=\"Section2\"\u003e\n \u003ch2\u003eVegetative growth responses of okra\u003c/h2\u003e\n \u003cp\u003eOkra vegetative growth parameters responded positively to compost treatment and were influenced by physiographic position (Figs. \u003cspan class=\"InternalRef\"\u003e9\u003c/span\u003e\u0026ndash;\u003cspan class=\"InternalRef\"\u003e13\u003c/span\u003e). Plant height increased progressively from week 2 to week 8 in all treatments (Fig. \u003cspan class=\"InternalRef\"\u003e9\u003c/span\u003e). Compost-amended soils consistently produced taller plants than the control in the crest, backslope, and toeslope positions. The highest plant heights were recorded in the toeslope, followed by the backslope, with the crest producing the shortest plants. Stem girth followed a similar pattern (Fig. \u003cspan class=\"InternalRef\"\u003e10\u003c/span\u003e). Compost-treated plants had wider stems than the control at all slope positions, and the toeslope maintained the largest girth values at each sampling time. The number of leaves increased with time and was higher in compost-amended soils than in unamended soils (Fig. \u003cspan class=\"InternalRef\"\u003e11\u003c/span\u003e). The toeslope position recorded the highest number of leaves. Leaf area increased with plant age, with compost treatments producing larger leaf areas in all positions (Fig. \u003cspan class=\"InternalRef\"\u003e12\u003c/span\u003e). Toeslope soils supported the largest leaf areas, followed by backslope and crest. Leaf area index (LAI) increased steadily across sampling dates, with compost producing higher LAI in all positions (Fig. \u003cspan class=\"InternalRef\"\u003e13\u003c/span\u003e). Toeslope soils recorded the highest LAI values.\u0026nbsp;\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec21\" class=\"Section2\"\u003e\n \u003ch2\u003eNutrient Uptake by Okra Across Physiographic Positions and Compost Levels\u003c/h2\u003e\n \u003cp\u003eCompost application significantly increased N, P, and K uptake across all physiographic positions (Table \u003cspan class=\"InternalRef\"\u003e7\u003c/span\u003e). Nutrient uptake followed the same spatial trend observed for soil moisture and enzyme activity, with higher uptake in backslope and toeslope soils relative to crest soils.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003ctable id=\"Tab7\" border=\"1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 7\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eNitrogen, phosphorus, and potassium uptake by okra under compost treatments across physiographic positions\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003ePhysiographic positions\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eCompost level\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eN\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eK\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e(t ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth colspan=\"3\" align=\"left\"\u003e\n \u003cp\u003emg plant\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCrest\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eControl (0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e35.63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e18.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e26.80\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e48.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e26.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e33.93\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eBackslope\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eControl (0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e44.73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e24.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e34.83\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e58.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e32.57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e41.70\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eToeslope\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eControl (0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e42.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e21.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e31.60\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e55.20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e29.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e38.90\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLSD (P\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e25.32\u003c/strong\u003e\u003csup\u003e\u003cstrong\u003e***\u003c/strong\u003e\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e22.34\u003c/strong\u003e\u003csup\u003e\u003cstrong\u003e***\u003c/strong\u003e\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e29.62\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\"\u003e*** = significance at P\u0026thinsp;\u0026le;\u0026thinsp;0.001\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec22\" class=\"Section2\"\u003e\n \u003ch2\u003ePost-harvest soil properties following okra cultivation\u003c/h2\u003e\n \u003cp\u003ePost-harvest soil properties improved under compost application across all slope positions (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e8\u003c/span\u003e). Increases in organic carbon, total nitrogen, available phosphorus, and exchangeable potassium indicate residual fertility benefits of compost amendment.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003ctable id=\"Tab8\" border=\"1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 8\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003ePost-harvest soil properties under compost treatments across physiographic positions following okra cultivation\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eSlope positions\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eCompost level\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003epH\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOrganic C\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eTotal N\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAvailable P\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eExchangeable K\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e(t ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth colspan=\"3\" align=\"left\"\u003e\n \u003cp\u003e(mg kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ecmol kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCrest\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eControl (0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e9400\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e900\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.38\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1200\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e14.77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.51\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eBackslope\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eControl (0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10200\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12.37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.44\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13400\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1300\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17.87\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.58\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eToeslope\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eControl (0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10800\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13.67\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.47\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12800\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1200\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e16.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.55\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003et-stat (p\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e123.38\u003c/strong\u003e\u003csup\u003e\u003cstrong\u003e***\u003c/strong\u003e\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e32.98\u003c/strong\u003e\u003csup\u003e\u003cstrong\u003e***\u003c/strong\u003e\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e34.26\u003c/strong\u003e\u003csup\u003e\u003cstrong\u003e***\u003c/strong\u003e\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e23.83\u003c/strong\u003e\u003csup\u003e\u003cstrong\u003e***\u003c/strong\u003e\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e29.75\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"7\"\u003e*** = significance at P\u0026thinsp;\u0026le;\u0026thinsp;0.001\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cdiv id=\"Sec23\" class=\"Section3\"\u003e\n \u003ch2\u003eCorrelation relationships among soil, microbial, enzyme, and plant parameters\u003c/h2\u003e\n \u003cp\u003eAcross all physiographic positions, soil moisture showed strong positive associations with enzyme activities, nutrient uptake, and vegetative growth parameters (Tables\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e9\u003c/span\u003e\u0026ndash;\u003cspan class=\"InternalRef\"\u003e11\u003c/span\u003e). In contrast, estimated redox potential (Eh) exhibited strong negative relationships with these variables. Microbial frequencies displayed weak and non-significant correlations with enzyme activity, nutrient uptake, and plant growth across all slope positions. This indicates that microbial occurrence alone was not a reliable predictor of functional soil processes or plant performance.\u003c/p\u003e\n \u003cp\u003eThe strong associations observed among soil moisture, estimated redox potential, enzyme activity, nutrient uptake, and growth parameters indicate closely linked hydro-biogeochemical dynamics across the physiographic gradient. These relationships indicate coordinated environmental controls rather than strictly independent mechanistic effects.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003ctable id=\"Tab9\" border=\"1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 9\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003ePearson correlation coefficients among soil moisture, redox potential, microbial frequency, enzyme activity, nutrient uptake, and okra growth parameters at crest position\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eProperties\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eFungal frequency\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eBacterial frequency\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSoil Moisture\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eEh\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth colspan=\"3\" align=\"left\"\u003e\n \u003cp\u003e(%)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e(mV)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSoil Moisture (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.1570\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2686\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.0000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eEh (mV)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1559\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.3001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9639\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCellulase (\u0026micro;g glucose g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e soil h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.1579\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2362\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9922\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9733\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eProtease (\u0026micro;g tyrosine g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e soil h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.1581\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2538\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9983\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9675\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePlant N (mg plant\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.1582\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2628\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9975\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9716\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePlant P (mg plant\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.1588\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2629\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9982\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9699\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePlant K (mg plant\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.1599\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2364\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9948\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9624\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePlant height (cm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.1571\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2555\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9985\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9628\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eStem girth (cm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.1557\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2627\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9982\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9466\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNumber of leaves\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.1515\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.0583\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.8828\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.7845\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLeaf Area (cm\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.1578\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2174\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9920\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9337\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLeaf Area Index (m\u003csup\u003e2\u003c/sup\u003e/m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.1578\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2174\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9920\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9337\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLSD (P\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ens\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ens\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026lt;0.001\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\"\u003e*** = significance at P\u0026thinsp;\u0026le;\u0026thinsp;0.001, ns\u0026thinsp;=\u0026thinsp;not significant\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003ctable id=\"Tab10\" border=\"1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 10\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003ePearson correlation coefficients among soil moisture, redox potential, microbial frequency, enzyme activity, nutrient uptake, and okra growth parameters at backslope position\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eProperties\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eFungal frequency\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eBacterial frequency\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSoil Moisture\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eEh\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth colspan=\"3\" align=\"left\"\u003e\n \u003cp\u003e(%)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e(mV)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSoil Moisture (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1386\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2177\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.0000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eEh (mV)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.1417\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.2141\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9785\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCellulase (\u0026micro;g glucose g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e soil h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1367\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2125\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9956\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9888\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eProtease (\u0026micro;g tyrosine g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e soil h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1349\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2113\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9936\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9890\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePlant N (mg plant\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1364\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2133\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9961\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9888\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePlant P (mg plant\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1375\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2120\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9968\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9878\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePlant K (mg plant\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1329\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2126\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9943\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9842\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePlant height (cm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1360\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2096\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9952\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9865\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eStem girth (cm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1330\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2112\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9949\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9827\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNumber of leaves\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1498\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2112\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9662\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9891\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLeaf Area (cm\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1347\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2101\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9947\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9861\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLeaf Area Index (m\u003csup\u003e2\u003c/sup\u003e/m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1347\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.2177\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9947\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9861\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLSD (P\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ens\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ens\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026lt;0.001\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\"\u003e*** = significance at P\u0026thinsp;\u0026le;\u0026thinsp;0.001, ns\u0026thinsp;=\u0026thinsp;not significant\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n \u003ctable id=\"Tab11\" border=\"1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 11\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003ePearson correlation coefficients among soil moisture, redox potential, microbial frequency, enzyme activity, nutrient uptake, and okra growth parameters at toeslope position\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eProperties\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eFungal frequency\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eBacterial frequency\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSoil Moisture\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eEh\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth colspan=\"3\" align=\"left\"\u003e\n \u003cp\u003e(%)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e(mV)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSoil Moisture (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1902\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1758\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.0000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eEh (mV)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.1658\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.1710\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9153\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCellulase (\u0026micro;g glucose g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e soil h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1922\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1764\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9991\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9181\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eProtease (\u0026micro;g tyrosine g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e soil h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1918\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1759\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9993\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9102\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePlant N (mg plant\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1921\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1767\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9993\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9205\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePlant P (mg plant\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1924\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1773\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9961\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9245\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePlant K (mg plant\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1904\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1756\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9965\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9250\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePlant height (cm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1899\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1764\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9991\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9188\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eStem girth (cm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1909\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1759\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9982\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.9103\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNumber of leaves\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1991\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1698\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9857\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.8677\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLeaf Area (cm\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1934\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1754\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9972\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.8982\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLeaf Area Index (m\u003csup\u003e2\u003c/sup\u003e/m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1934\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1754\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.9972\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.8982\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLSD (P\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ens\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ens\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026lt;0.001\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\"\u003e*** = significance at P\u0026thinsp;\u0026le;\u0026thinsp;0.001, ns\u0026thinsp;=\u0026thinsp;not significant\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003c/div\u003e\n\u003c/div\u003e"},{"header":"Discussion","content":"\u003cdiv id=\"Sec25\" class=\"Section2\"\u003e \u003ch2\u003eCompost maturation dynamics and implications for soil amendment\u003c/h2\u003e \u003cp\u003eThe physicochemical trends observed during composting indicate a well-defined aerobic decomposition process that produced a stable and mature poultry-manure-based compost. The sharp rise in temperature from week 0 to week 2 reflects rapid microbial oxidation of labile carbon, consistent with thermophilic composting reported by Papale et al. (\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e2021\u003c/span\u003e) and Wang et al. (\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). The subsequent temperature decline indicates the transition to the curing phase as metabolic heat generation reduces. Reductions in organic carbon and the steady increase in total nitrogen lowered the C/N ratio from 17.4 to 6.4, within maturity thresholds reported by Jakubus (\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2020\u003c/span\u003e) and Ouali et al. (\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2025\u003c/span\u003e), confirming stability. Heavy metals (Zn, Pb, Cd, Cr, Cu, Ni) declined over compost maturation, consistent with dilution through biomass increase, complexation, and adsorption onto humified organic matter (Okoro et al., \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2025\u003c/span\u003e). Concurrent increases in exchangeable Ca, Mg, K, and Na reflect mineral release, ash enrichment, and retention on soil colloids, contributing to improved cation exchange capacity and nutrient buffering (Jakubus, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2020\u003c/span\u003e).\u003c/p\u003e \u003cdiv id=\"Sec26\" class=\"Section3\"\u003e \u003ch2\u003eSoil moisture and redox shifts across physiographic positions\u003c/h2\u003e \u003cp\u003eCompost application increased soil moisture retention across all physiographic positions, consistent with the role of organic amendments in improving soil structure, porosity, and aggregate stability (Rasa et al., \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Tao et al., \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). The observed gradient (toeslope\u0026thinsp;\u0026gt;\u0026thinsp;backslope\u0026thinsp;\u0026gt;\u0026thinsp;crest) reflects inherent topographic redistribution of water along the catena, as reported in similar toposequence studies (Omokaro, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Okebalama et al., \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2025\u003c/span\u003e). The corresponding decline in redox potential with increasing moisture is consistent with enhanced microbial respiration and oxygen consumption in organic-amended soils (Dorau et al., 2018). Greater reductions in Eh at the toeslope indicate prolonged moisture retention and reduced aeration, which support sustained microbial activity. These findings highlight the central role of hydro-redox conditions as regulators of soil biochemical functioning across landscape positions.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec27\" class=\"Section3\"\u003e \u003ch2\u003ePhysiographic control of soil biochemical functioning\u003c/h2\u003e \u003cp\u003eThe three physiographic positions established distinct hydrochemical environments that governed microbial processes, nutrient transformations, and plant nutrient acquisition. Baseline differences in moisture, pH, bulk density, and organic carbon created contrasting aeration regimes and redox conditions, which are key regulators of carbon and nutrient cycling in tropical soils (Bhanwaria et al., \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). Crest soils, characterized by lower moisture and higher redox potential, favoured rapid oxygen diffusion but limited the persistence of microoxic zones necessary for sustained microbial activity (Dorau et al., 2018). In contrast, backslope and toeslope soils maintained higher moisture and lower redox potentials, supporting a broader spectrum of aerobic and facultative microbial metabolisms (Omokaro, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Okebalama et al., \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2025\u003c/span\u003e). These inherent differences conditioned the magnitude of soil and plant responses following compost application.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec28\" class=\"Section2\"\u003e \u003ch2\u003eCompost-induced modification of soil microhabitats\u003c/h2\u003e \u003cp\u003eCompost amendment enhanced both fungal and bacterial frequencies across all physiographic positions, reflecting increased substrate availability and improved microenvironmental conditions. The dominance of taxa such as \u003cem\u003eAspergillus, Penicillium, Cladosporium, Trichoderma, Rhizopus, Bacillus, Pseudomonas\u003c/em\u003e, and \u003cem\u003eStreptomyces\u003c/em\u003e is consistent with known decomposer and plant growth-promoting groups in organic-amended soils (Chauhan et al., \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Compost contributed both nutrients and organic substrates, including labile and semi-labile carbon fractions, which stimulated microbial proliferation and metabolic activity (Li et al., \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Chen et al., \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). The associated increase in soil moisture and organic colloids improved water-holding capacity and stabilized aggregates, promoting longer water residence times and reduced oxidative stress. These changes collectively lowered redox potential and enhanced microbial respiration (Liu et al., \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Rahman \u0026amp; Thomas, \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2021\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eToeslope soils consistently supported the highest microbial frequencies, reflecting favourable moisture and nutrient conditions (Borowik \u0026amp; Wyszkowska, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2016\u003c/span\u003e; Zhang et al., \u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). However, the relatively weak correlations between microbial frequency and plant growth variables indicate that microbial presence alone did not directly determine plant performance, but rather operated through functional pathways such as enzyme-mediated nutrient transformation and soil structural improvement.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec29\" class=\"Section2\"\u003e \u003ch2\u003eEnvironmentally mediated microbial-enzyme interactions\u003c/h2\u003e \u003cp\u003eAlthough microbial frequencies increased under compost amendment, enzyme activities showed stronger associations with soil moisture and redox conditions than with microbial occurrence. This indicates that enzyme expression was primarily regulated by microenvironmental conditions rather than by microbial frequency alone. Cellulase and protease activities increased progressively during crop growth, reflecting active decomposition of organic carbon and nitrogen substrates. These enzymes are central to carbon and nitrogen mineralization, and their enhancement under compost treatment is consistent with increased microbial metabolic activity in moisture-favourable environments (Zhang et al., \u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Solangi et al., \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). The strong positive relationships between enzyme activity and plant growth parameters indicate that enzyme-mediated nutrient release was a key driver of crop performance. Higher enzyme activities in backslope and toeslope soils further emphasize the importance of hydro-redox conditions in sustaining microbial functionality.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eNutrient mineralization and vegetative growth responses\u003c/h3\u003e\n\u003cp\u003eCompost application significantly improved vegetative growth parameters of okra, including plant height, stem girth, leaf number, leaf area, and leaf area index, across all physiographic positions. These improvements are attributable to enhanced soil structure, increased moisture retention, and improved nutrient availability through microbial and enzymatic processes (Adewole \u0026amp; Ilesanmi, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2012\u003c/span\u003e; Nengi-Benwari \u0026amp; Abah, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2025\u003c/span\u003e). Growth responses followed the gradient toeslope\u0026thinsp;\u0026gt;\u0026thinsp;backslope\u0026thinsp;\u0026gt;\u0026thinsp;crest, reflecting topographic influences on soil moisture, aeration, and nutrient dynamics. Increased water availability at lower slope positions enhanced nutrient diffusion, microbial activity, and root physiological processes, consistent with findings by Belay et al. (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2025\u003c/span\u003e) and Cai et al. (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2025\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eIncreased uptake of N, P, and K under compost amendment indicates efficient mineralization and nutrient release. Protease activity supports nitrogen mineralization, while cellulase activity contributes to carbon turnover that fuels microbial nutrient transformations. Improved pH buffering and increased exchangeable bases further enhanced nutrient retention and reduced phosphorus fixation, contributing to improved plant performance (Okole et al., \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2025\u003c/span\u003e; Frimpong et al., \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2017\u003c/span\u003e; Adekiya et al., \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2020\u003c/span\u003e).\u003c/p\u003e \u003cdiv id=\"Sec31\" class=\"Section2\"\u003e \u003ch2\u003eHydro-redox control of nutrient fluxes\u003c/h2\u003e \u003cp\u003eThe inverse relationship between redox potential and nutrient uptake suggests that moderately reduced conditions supported nutrient mineralization and availability. While excessively low redox conditions may promote denitrification, the observed increases in total nitrogen and plant uptake indicate that mineralization processes dominated under the conditions of this study. The strong association between soil moisture and nutrient uptake highlights hydrological status as a key determinant of nutrient fluxes, reinforcing the coupling between moisture, redox dynamics, and nutrient mobility in slope-differentiated soils.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec32\" class=\"Section2\"\u003e \u003ch2\u003eSlope-dependent variation in compost effectiveness\u003c/h2\u003e \u003cp\u003eAlthough compost improved soil quality and plant performance across all positions, the magnitude of response varied significantly. Backslope and toeslope soils exhibited greater improvements due to favourable moisture and aeration regimes that enhanced microbial and enzymatic activity. Crest soils showed comparatively lower responses due to inherent hydrological limitations. These findings demonstrate that the effectiveness of organic amendments is strongly mediated by landscape position, and that uniform application rates may produce variable outcomes depending on slope-controlled soil processes.\u003c/p\u003e \u003cdiv id=\"Sec33\" class=\"Section3\"\u003e \u003ch2\u003eLimitations and future directions\u003c/h2\u003e \u003cp\u003eWhile the study provides strong empirical evidence of physiographic control over compost-mediated soil processes, certain limitations should be acknowledged. Intermediate nutrient pools such as ammonium, nitrate, and soluble phosphorus were not directly quantified. Future studies incorporating soil solution monitoring, microbial functional gene analysis, and gaseous nitrogen flux measurements would enhance mechanistic resolution. Additionally, direct measurement of redox potential using electrode-based methods would further strengthen interpretation of hydro-redox dynamics.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec34\" class=\"Section3\"\u003e \u003ch2\u003eContribution to knowledge\u003c/h2\u003e \u003cp\u003eThis study demonstrates that the agronomic effectiveness of poultry manure-based compost is strongly mediated by physiographic controls on soil moisture, redox potential, and microbial functioning. The results reveal a coherent biogeochemical cascade linking compost application to microbial activity, enzyme expression, nutrient mineralization, and plant growth, with landscape position modulating each stage. These findings provide mechanistic evidence that site-specific organic amendment strategies are essential for optimizing nutrient use efficiency and crop productivity in tropical agroecosystems, reinforcing the importance of soil-plant-microbe interactions within heterogeneous landscapes (Battacharyya \u0026amp; Furtak, 2023; Wang et al., \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e2025\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Conclusion and Recommendations","content":"\u003cp\u003eThis study demonstrates that poultry-manure-based compost significantly enhances soil biochemical functioning, nutrient dynamics, and okra performance across contrasting physiographic positions in a southern Guinea Savanna environment. Compost application improved soil moisture retention and modified redox conditions, which stimulated microbial activity, increased cellulase and protease expression, and enhanced nutrient mineralization. These processes resulted in increased uptake of nitrogen, phosphorus, and potassium, leading to improved vegetative growth. The magnitude of these responses was strongly influenced by physiographic position, with backslope and toeslope soils consistently outperforming crest soils due to more favourable hydro-redox conditions. Compost application also improved post-harvest soil fertility indicators, demonstrating its potential for sustained soil quality enhancement. The findings highlight the importance of integrating landscape variability into organic amendment strategies to optimize crop productivity and nutrient use efficiency in tropical systems.\u003c/p\u003e \u003cp\u003eRecommendations include adjusting compost rates or irrigation at crests, integrating mulch or micro-catchments on drier slopes, monitoring soil moisture, redox potential, and enzyme activities, and promoting on-farm poultry manure composting for sustainable smallholder systems.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cem\u003eEthics approval and consent to participate\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThis study did not involve human participants, huma data, or animals. All plant materials used in this study complied with relevant institutional, national, and international guidelines for plant research. The study involved cultivated crop species (\u003cem\u003eAbelmoschus esculentus\u003c/em\u003e L. Moench) and did not involve endangered or protected plant species.\u003c/p\u003e\n\u003cp\u003ePlant materials were sourced from a certified agricultural input supplier registered with the Kwara State Ministry of Agriculture. The study did not involve collection of plant specimens from government-protected land, private farmland, or natural ecosystems requiring special permits. Soil Samples were collected from the University of Ilorin Teaching and Research Farm with Institutional approval for research purposes.\u003c/p\u003e\n\u003cp\u003eNo specific permits or licenses were required for the use of commercially cultivated okra seeds or soil sampling within the University research farm. All procedures complied with standard agronomic and environmental research regulations in Nigeria.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eConsent for publication\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAvailability of data and materials\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eAll data generated or analysed during this study are included in this manuscript. Additional information related to the datasets used and analysed during the current study is available from the corresponding author upon reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eClinical trial number\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eCompeting interests\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that there are no competing interests, financial or non-financial, that could have influenced the work reported in this manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eFunding\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThis research received no external funding. The study was supported by institutional research facilities and personal resources.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAuthors’ contributions\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eYahaya, James Ukwumonu and Fawole, Oluyemisi Bolajoko conceived and designed the study. Yahaya, James Ukwumonu, Olasupo, Hammed Alabi, and Ikuoponiyi, Damilola Abigael conducted the experiment. Yahaya, James Ukwumonu, performed data analysis and drafted the manuscript. \u0026nbsp; Yahaya, James Ukwumonu, Fawole, Oluyemisi Bolajoko and Isiaka, kareem, and Oni, Femi Emmanuel reviewed and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAcknowledgements\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe authors acknowledge the technical support provided by the staff of the screenhouse facility and laboratory units where soil and plant analyses were conducted. Appreciation is extended to colleagues who provided constructive feedback during manuscript preparation\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eAdekiya AO, Agbede TM, Aboyeji CM, Dunsin O. Response of okra (\u003cem\u003eAbelmoschus esculentus\u003c/em\u003e (L.) 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Front Ecol Evol. 2023;10:1107421.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZhang L, Li L, Pan X, Shi Z, Feng X, Gong B, Li J, Wang L. Enhanced Growth and Activities of the Dominant Functional Microbiota of Chicken Manure Composts in the Presence of Maize Straw. Front Microbiol. 2018;9:1131.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZheng S, Wu J, Sun L. Effects of different conditioners on soil microbial community and labile organic carbon fractions under the combined application of swine manure and straw in black soil. Agronomy. 2024;14:879.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZhou Y, Taylor RJ, Boutton TW. (2021). Divergent patterns and spatial heterogeneity of soil nutrients in a complex and dynamic savanna landscape. J Geophys Research: Biogeosciences, 126, e2021JG006575.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"discover-plants","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Discover Plants](https://link.springer.com/journal/44372)","snPcode":"44372","submissionUrl":"https://submission.springernature.com/new-submission/44372/3","title":"Discover Plants","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Compost, soil physiography, hydro-redox conditions, microbial-enzyme interactions, nutrient mineralisation, okra, Guinea Savanna","lastPublishedDoi":"10.21203/rs.3.rs-9214501/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9214501/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003ePhysiographic gradients strongly influence soil hydro-redox conditions, yet their interaction with organic amendments in tropical savannas remains poorly understood. This study evaluated how slope position modulates compost-induced microbial enzyme activity, nutrient uptake, and vegetative growth of okra (\u003cem\u003eAbelmoschus esculentus\u003c/em\u003e L.) in a southern Guinea savanna soil. A 3 × 2 factorial experiment (crest, backslope, toeslope × 0 or 20 t ha\u003csup\u003e-1\u003c/sup\u003e compost) was conducted under screenhouse conditions with three replicates over 8 weeks. Soil moisture, estimated redox potential (Eh), microbial frequency, enzyme activities (cellulase and protease), nutrient uptake, and vegetative growth parameters were assessed. Compost application significantly increased soil moisture, enzyme activity, nutrient uptake, and plant growth across all positions (P ≤ 0.001). Moisture consistently followed the gradient toeslope \u0026gt; backslope \u0026gt; crest, while estimated Eh showed an inverse trend. Cellulase and protease activities were highest in compost-amended toeslope soils and were strongly associated with soil moisture (r ≥ 0.99; P ≤ 0.001). In contrast, microbial frequency showed weak, non-significant relationships with enzyme activity and plant performance. Nitrogen, phosphorus, and potassium uptake increased by 28-36% under compost application, with the greatest response observed in backslope and toeslope soils. Vegetative growth parameters exhibited similar spatial patterns. The results demonstrate a physiography-driven biogeochemical cascade in which soil moisture and redox conditions regulate enzyme-mediated nutrient mineralization and crop response. These findings highlight that compost effectiveness is strongly dependent on landscape position and emphasize the need for site-specific soil fertility management in tropical agroecosystems.\u003c/p\u003e","manuscriptTitle":"Physiographic Modulation of Soil Hydro-redox Conditions and Compost-induced Microbial Dynamics, Enzyme Activity, Nutrient Uptake in Okra","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-05-13 07:35:19","doi":"10.21203/rs.3.rs-9214501/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorInvitedReview","content":"","date":"2026-05-15T19:31:20+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-05-09T12:46:51+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"12030338371808992527857333960833598371","date":"2026-05-07T06:59:28+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"69556013717354118682989001066967297192","date":"2026-05-05T19:03:09+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-05-05T06:18:40+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-05-05T06:15:44+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-04-02T04:06:09+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-30T12:37:09+00:00","index":"","fulltext":""},{"type":"submitted","content":"Discover Plants","date":"2026-03-30T12:32:24+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"discover-plants","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Discover Plants](https://link.springer.com/journal/44372)","snPcode":"44372","submissionUrl":"https://submission.springernature.com/new-submission/44372/3","title":"Discover Plants","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"3014505b-7617-4e29-b1bf-5a30f5f3dec3","owner":[],"postedDate":"May 13th, 2026","published":true,"recentEditorialEvents":[{"type":"editorInvitedReview","content":"","date":"2026-05-15T19:31:20+00:00","index":46,"fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-05-09T12:46:51+00:00","index":43,"fulltext":""},{"type":"reviewerAgreed","content":"12030338371808992527857333960833598371","date":"2026-05-07T06:59:28+00:00","index":42,"fulltext":""},{"type":"reviewerAgreed","content":"69556013717354118682989001066967297192","date":"2026-05-05T19:03:09+00:00","index":41,"fulltext":""},{"type":"reviewersInvited","content":"15","date":"2026-05-05T06:18:40+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-05-05T06:15:44+00:00","index":"","fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-13T07:35:20+00:00","versionOfRecord":[],"versionCreatedAt":"2026-05-13 07:35:19","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9214501","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9214501","identity":"rs-9214501","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}