Optimizing Cattle and Goat Manure Quality in Semi-arid Agrozone to Improve Fertility Status of Fragile Soils of Samburu County, Kenya

Optimizing Cattle and Goat Manure Quality in Semi-arid Agrozone to Improve Fertility Status of Fragile Soils of Samburu County, Kenya | 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 Optimizing Cattle and Goat Manure Quality in Semi-arid Agrozone to Improve Fertility Status of Fragile Soils of Samburu County, Kenya Patrick Lpimari Lesharana, Erick Oduor Otieno, Mwende Ngie, Joseph Patrick Gweyi-Onyango This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7545517/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The study assessed the effects of different composting strategies on compost quality and chemical characteristics of ASAL soils. A field trial was laid in a randomized complete block design with: control, cattle manure from open compost pit, goat manure + ash from compost pit, cattle manure from covered compost pit, goat manure from open compost pit, goat manure from covered pit, and cattle manure + ash from compost pit. Covered pits at 50 cm depth recorded the highest Nitrate- N levels (188.0 ppm), followed by open pits at 100 cm (148.0 ppm). Goat manure stored in covered pits had significantly lower subsoil nitrate (0.13 ± 0.14) compared with cattle manure in open or covered pits (T2 and T4; 0.47 ± 0.15 and 0.47 ± 0.03, respectively). Soil moisture content improved significantly from 17.08% in T1 to 23.05% in covered pits. The lowest soil bulk density was recorded under plots receiving compost from the covered pits (1.02 g/cm³). Moreover, nitrate-N at a depth of 10–20 cm (p = 0.01) showed a significant treatment effect. Compost from covered pits could be a sustainable approach to enhancing soil fertility and improving agricultural productivity in ASAL soils. Manure management mineral nitrogen. nutrient retention smallholder farming nitrogen conservation Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 1. Introduction Increasing global population contributes to soil fertility depletion leading to food security challenges (FAO, 2019 ). More food demands have resulted in the expansion of intensive livestock production, leading to the production of huge amounts of animal manure that pose a severe environmental concern. Balancing the trade-off between increased livestock herds and protecting soil fertility integrity is crucial (Rayne & Aula, 2020 ).. Manure produced by the livestock manure can be harnessed to enhance soil fertility for crop production particularly in arid and semi-arid (ASAL) regions where pastoralism is the mainstay economic activity (Fang et al., 2024 ; Zougmoré et al., 2016 ). The need to attain manure management practices that are environmentally friendly has called for the adaptation of actions to improve its sustainable production worldwide (Miner et al., 2020 ; Mubarak et al., 2010 ). Additionally, the advancements in the livestock industry are increasing the importance of suitable manure management systems and practices. Nevertheless, a majority of farmers, particularly in sub-Sahara Africa (SSA), do not practice the recommended manure management strategies leading to significant nutrient losses through leaching, run-off and volatilization, and increased greenhouse gases emissions. Consequently, there has not been the desired improvement in soils amended with the manure (Miner et al., 2020 ). The inadequate land area for proper manure management has been reported to be one of the pertinent challenges among smallholder farmers (Duan et al., 2023 ; Islam et al., 2024 ). As a result, livestock manure has become a public health (Zhao et al., 2020 ) and environmental menace. Moreover, manure may cause soil acidification, contamination of ground and surface water, and greenhouse gas emission (Borase et al., 2020 ) if not well managed. It is, therefore, imperative to promote sustainable manure management strategies, especially in the fragile ASAL soils. Arid and semi-arid regions are likely to play a crucial role in food security due human population and climate change pressures. However, ASAL soils are fragile and could be further degraded. It is important that researchers leverage locally produced manure to build the resilience of these soils (Fang et al., 2024 ; Guo et al., 2016 ). For instance, storage strategies are crucial in enhancing the quality of manure and its impact on soil fertility. Despite this, knowledge of the impact of storage strategies on manure quality and its impact on soil chemical characteristics are not well established, especially in the fragile soils of ASAL regions. The current study hypothesized that storage strategies impact manure quality and soil chemical characteristics of ASAL soils. Therefore, the aim of this study was to evaluate the effect of different management strategies on manure quality and chemical properties of ASAL soils in Samburu County. 2. Materials and methods 2.1 Study site The experimental carried out in Ngari location, Maralal ward (1.079782° N latitude and 36.713163° E), within Samburu County. The site is located in arid and semiarid regions of Kenya characterized by low rainfall patterns and high temperatures. It experiences bimodal rainfall between March (long rains) and October (short rains), receiving an average annual rainfall of 600–1200 mm. The monthly minimum and maximum temperatures are 22°C and 30°C, respectively, as well as the mean relative humidity of 80%. Soils in the county are classified as Ferric Acrisols (Jaetzold et al., 2007 ). The dominant economic activity in the area is pastoralism, which supports the livelihoods of over 80% of the population. However, significant livestock populations, including cattle, goats, sheep, camels, and donkeys, which are not only sources of income but also contribute substantially to manure production. Livestock keeping is both a cultural and economic cornerstone for the Samburu community. In addition to livestock rearing, small-scale subsistence farming is practiced in areas with slightly higher rainfall and access to water, such as the Maralal escarpment (UNICEF Report, 2018 ). 2.2 Experimental design Six separate compost pits were set; three for cattle manure and three for goat manure, with each pit capable of accommodating 1 ton of material. The composting pits used in the study measured 1 m × 1 m in width and 1 m in depth, dimensions considered adequate to accommodate the volume of manure and allow for effective aeration and manual turning (Guo et al., 2016 ). Turning of the compost was conducted manually using a garden fork to facilitate aerobic decomposition by enhancing oxygen penetration, redistributing moisture, and balancing microbial activity (Zhou et al., 2025 ). A total of six turnings were carried out throughout the composting period, which lasted approximately 90 days. The first turning was done on Day 7, followed by subsequent turnings at two-week intervals (Days 21, 35, 49, 63, and 77). The decision to adopt a biweekly turning schedule was informed by established composting guidelines which recommend turning every 10–15 days for small-scale compost piles, especially under tropical or subtropical conditions, to maintain adequate oxygen supply and thermophilic activity (Ramaswamy et al., 2010 ). A pit for cattle and goat manure were left open. Ash was added in the second cattle manure and goat manure pits at the rate 100 kg per ton. The third set of cattle manure and goat manure pits were covered using nylon slightly above the compost piles. 2.3 Design of field trials A field trial experiment was conducted using a randomized complete block design (RCBD) with 7 treatments and each replicated three times on plots measuring 1.5 m x 1.5 m separated by paths measuring 0.5 m, between replications, and 0.5 m between treatments. The following treatments were applied: Treatment 1: control; Treatment 2: cattle manure from open compost pit; Treatment 3: goat manure ash added compost pit; Treatment 4: cattle manure from covered compost pit; Treatment 5: goat manure from open compost pit; Treatment 6: Goat manure from covered pit; Treatment 7: cattle manure ash added compost pit. 2.4 Determination of OC and N Compost samples were collected from 0 cm, 50 cm, and 100 cm depths from each pit, thoroughly mixed, and about 500 g subsamples were obtained, placed in zip locks, and transported to Kenyatta University laboratory in a cool-box fitted with ice-cubes. Soil organic carbon was determined by a Carbon Nitrogen (CN) Elemental Analyser. 2.5 g of air-dried soil were weighed into centrifuge tubes, 18 mL distilled water (DI) and 2 mL (0.2 M) K 2 MnO 4 added, shaken at 240 revolutions per minute for 2 min, tubes removed and allowed to settle for 10 min, thereafter 0.5 mL of the supernatant was taken and mixed with 49.5 mL of DI. From each sample, 200 µl aliquots were extracted and their concentrations read with a spectrophotometer set at a wavelength of 550 nm. Mineral N (NH 4 + -N and NO 3 –N) was determined based on the method adopted by Gomez-Munoz et al. ( 2017 ). Approximately 5 g of oven-dried soil was placed in 100 ml shaking bottles. About 50 ml of 0.5 M K 2 SO4 was then added into the bottle and shaken on reciprocal shaker at 200 rmp for thirty minutes after which it was filtered using Whatman no. 42 filter papers (Otieno et al., 2024 ). Ammonium N and NO 3 –N were then determined using UV spectrophotometer at 655 nm and 419 nm, respectively. Soil texture was determined using the hydrometer method. Soil bulk density and moisture content (SMC) were determined gravimetrically (Otieno et al., 2023 ). Fifteen (15) grams of soil samples were collected from 0–20 cm using a core ring with a known volume for bulk density determination. The soil samples were oven-dried at 105°C for 24 h until constant weights were attained. Bulk density and SMC were then calculated using equations 1 and 2 . \(\:\text{B}\text{u}\text{l}\text{k}\:\text{d}\text{e}\text{n}\text{s}\text{i}\text{t}\text{y}\:\left(\text{g}\:{cm}^{-3}\right)=\frac{\text{S}\text{o}\text{i}\text{l}\:\text{S}\text{o}\text{l}\text{i}\text{d}\text{s}\:\left(\text{M}\text{s}\right)}{\text{T}\text{o}\text{t}\text{a}\text{l}\:\text{V}\text{o}\text{l}\text{u}\text{m}\text{e}\:\text{o}\text{f}\:\text{S}\text{o}\text{i}\text{l}\:\left(\text{V}\text{t}\right)}\) (1) \(\:\text{G}\text{r}\text{a}\text{v}\text{i}\text{m}\text{e}\text{t}\text{r}\text{i}\text{c}\:\text{S}\text{M}\text{C}\:\left(\text{%}\right)=\frac{\left(\text{T}\text{o}\text{t}\text{a}\text{l}\:\text{s}\text{o}\text{i}\text{l}\:\text{m}\text{a}\text{s}\text{s}\left(\text{M}\text{t}\right)-\text{S}\text{o}\text{i}\text{l}\:\text{s}\text{o}\text{l}\text{i}\text{d}\text{s}\left(\text{M}\text{s}\right)\right)}{\text{S}\text{o}\text{i}\text{l}\:\text{S}\text{o}\text{l}\text{i}\text{d}\text{s}\:\left(\text{M}\text{s}\right)}\text{x}\:100\) (2) 2.5 Statistical analysis The biophysical data were subjected to analysis of variance using R software. A post hoc analysis using HSD turkey at p ≤ 0.05 were means were significantly different. 3. Results and Discussion 3.1 Interactive effects of management practices and depths on goat manure quality Interaction between management strategies and depth had significant effects on manure quality parameters (Table 1 ). The interaction between covered pits and 100 cm and 50 cm depths had significantly higher OC by 60 and 59% compared to open pits at 0 cm depth, respectively. Similarly, open pits at 50 and100 cm depths greatly improved OC by 52 and 42% relative to open pits at 0 cm. Compared at 0 cm, covered pits remarkably enhanced OC by 37% compared to the open pits. The increased OC under covered and deeper pits may be attributed to reduced volatilization and enhanced microbial activity under stable thermal and moisture conditions (Li et al., 2021 ). Similar obervations were made by Hao et al., 2004 who noted that oxygen regulation and moisture retention in covered systems favor carbon stabilization and humification processes. The management strategies significantly influenced the concentration of mineral nitrogen, including Nitrate – N and Ammonium – N. Covered pits at 50 cm depth recorded the highest Nitrate- N levels (188.0 ppm), followed by open pits at 100 cm (148.0 ppm), both significantly greater than open pits at 0 cm (57.1ppm). Covered pits foster aerobic zones conducive to nitrifier activity, leading to greater nitrate accumulation. Conversely, the low nitrate content in open pits at shallow depth may be due to nitrogen volatilization and leaching losses (McCullough, 2024 ). Total Nitrogen (TN) also responded significantly (p < 0.001) to the interaction of the management strategies and depth (Table 1 ). The total Nitrogen (0.71%) was recorded in the covered pits at 50 cm depth, marking a 173% increase compared to open pits at 0 cm (0.26%). Covered pits at 100 cm and 0 cm also showed increases of 123% and 123%, respectively. Open pits at 50 cm and 100 cm improved TN by 104% and 100%, respectively compared to open pits at 0 cm. These increases are likely due to better nitrogen conservation through reduced leaching, minimized ammonia volatilization, and the slower breakdown of nitrogen-rich compounds under covered, moisture-regulated conditions. These findings align with those of Zhao et al. ( 2020 ), who emphasized the effectiveness of controlled composting environments in preserving nitrogen content during decomposition. Table 1 Mean goat manure quality parameters ± standard error under management practices and depths interactions Management practice Depths OC (%) Nitrate-N (ppm) Ammonium-N (ppm) TN (%) Covered pit 0 cm 3.63 ± 0.23 d 70.6 ± 3.4 cd 484 ± 53.8 b 0.58 ± 0.06 ab Open pit 0 cm 2.28 ± 0.14 e 57.1 ± 8.9 d 56 ± 2.2 c 0.26 ± 0.02 c Covered pit 50 cm 5.61 ± 0.46 ab 188.0 ± 13.5 a 679 ± 96.3 a 0.71 ± 0.12 a Open pit 50 cm 4.76 ± 0.37 bc 69.5 ± 16.9 cd 109 ± 16.2 c 0.53 ± 0.03 b Covered pit 100 cm 5.70 ± 0.53 a 97.4 ± 16.8 c 707 ± 88.5 a 0.58 ± 0.06 ab Open pit 100 cm 3.96 ± 0.14 cd 148.0 ± 13.5 b 197 ± 9.0 c 0.52 ± 0.04 b p value < 0.001 < 0.001 < 0.001 < 0.001 Means with the same letter(s) within the same column are not significantly different at p ≤ 0.05, ± = standard errors of the mean. 3.2 Interactive effects of management practices and depths on cattle manure at different depths The organic carbon (OC) content varied significantly with compost management strategy and depth (p < 0.001) (Table 2 ). The open pit at 0 cm recorded an OC content of 1.03%. In contrast, covered pits at 100 cm and 50 cm depths exhibited the highest OC values at 6.51% and 6.44%, representing 532% and 525% increases over the control. Similarly, the open pit at 50 cm recorded 5.67% OC, a 451% rise compared to the control. Open pit at 100 cm yielded 3.78%, an increase of 267%, while the covered pit at 0 cm had 0.75%, slightly lower (27% decrease) than the control. These results demonstrate that increasing composting depth substantially enhances OC accumulation, particularly in covered systems. The elevated OC observed under deep, covered pits may be attributed to reduced oxygen exposure and minimal physical disturbance, which limit organic matter degradation and carbon dioxide volatilization. Additionally, covering the compost moderates internal temperatures and retains moisture, thereby supporting microbial activity and humification. Similar findings were reported by Duan et al. ( 2023 ), who found that reduced aeration and improved moisture regulation in covered compost piles enhance carbon retention. Wang et al. ( 2025 ) also noted that composting under controlled microclimatic conditions, such as in deeper or covered systems, leads to greater preservation of organic carbon by slowing down oxidative decomposition. Table 2 Mean cattle manure quality parameters ± standard errors under management practices and depths interactions Management practice Depths OC (%) Nitrate -N (ppm) Ammonium -N (ppm) TN (%) Open pit 0 cm 1.03 ± 0.11 c 66.4 ± 10.9 ab 86 ± 9.53 d 0.15 ± 0.03 c Covered pit 0 cm 0.75 ± 0.02 c 59.6 ± 7.55 b 76 ± 13.40 d 0.16 ± 0.05 c Covered pit 50 cm 6.44 ± 0.52 a 68.6 ± 3.46 ab 287 ± 30.3 b 0.71 ± 0.04 a Open pit 50 cm 5.67 ± 0.67 a 83.2 ± 7.33 a 141 ± 6.7 0 c 0.44 ± 0.05 b Covered pit 100 cm 6.51 ± 0.52 a 75.0 ± 6.98 ab 349 ± 4.45a 0.60 ± 0.07 a Open pit 100 cm 3.78 ± 0.20 b 71.9 ± 8.13 ab 321 ± 25.8 ab 0.39 ± 0.05 b p value < 0.001 0.04 < 0.001 < 0.001 Means with the same letter(s) within the same column are not significantly different at p ≤ 0.05, ± = standard errors of the mean. 3.3 Interactive effects of management practice and depths on goat and cattle manure The goat and cattle manure treated with ash, across different depths (0 cm, 50 cm, and 100 cm), on organic carbon (OC), nitrate-nitrogen (NO₃⁻-N), ammonium-nitrogen (NH₄⁺-N), and total nitrogen (TN). Organic carbon was significantly influenced by treatment (p = 0.007). The highest OC content was recorded in cattle manure treated with ash at 100 cm (6.05 ± 0.62%), followed closely by the same treatment at 50 cm (5.78 ± 0.21%). This represents an increase of 3.75% OC compared to the lowest value observed in open pit goat manure without ash treatment (2.30%). Comparing application at 0 cm in open pits without ash to deep placement of cattle manure treated with ash (100 cm), OC content increased by 3.75%. Similarly, in goat manure, OC rose from 2.3% at 0 cm to 3.9% at 100 cm with ash treatment an improvement of 1.6%. These increments highlight the effectiveness of both ash amendment and depth in preserving organic carbon. This aligns with Nzeyimana et al. (2021), who emphasized that deeper burial reduces carbon mineralization by limiting microbial access to oxygen. The role of ash in stabilizing OC likely stems from its alkaline pH, which buffers the compost environment, and its mineral content, which facilitates the formation of organo-mineral complexes that reduce microbial decomposition rates (Kumar et al., 2023). Nitrate-nitrogen (NO₃⁻-N) concentrations were generally higher in surface applications and declined with depth, particularly in goat manure treatments. The highest NO₃⁻-N level was observed in goat manure without ash at the surface (38.1 ± 2.1 mg kg -1 ), which decreased by 17.5 mg kg -1 at 100 cm depth (20.6 ± 1.4 mg kg -1 ). Ammonium-nitrogen (NH₄⁺-N), in contrast, increased with depth, especially under ash-treated cattle manure, rising from 18.3 ± 1.2 mg kg -1 at 0 cm to 31.5 ± 2.0 mg/kg at 100 cm a 13.2 mg kg -1 increase. Total nitrogen (TN) followed a similar trend to OC. The highest TN (0.85 ± 0.04%) was measured in ash-treated cattle manure at 100 cm depth, representing an increase of 0.37% compared to the lowest TN recorded in untreated goat manure at the surface (0.48 ± 0.03%). The deeper placement of manure likely reduced nitrogen losses through volatilization and leaching, which are more pronounced in surface applied treatments exposed to rainfall and temperature fluctuations (Islam et al., 2024 ). This result agrees with the finding of Huang et al. ( 2017 ) who found that placement at 100 cm may also limit gaseous nitrogen losses by creating microenvironments with restricted aeration, thus slowing nitrification denitrification pathways and favoring nitrogen retention in organic and ammonium forms. Nitrogen dynamics reflected depth and treatment interactions. Top application at 0 cm exhibited higher nitrate (NO₃⁻-N) levels, likely due to increased nitrification under aerobic conditions, where oxygen availability supports the microbial oxidation of ammonium to nitrate (Subbarao et al., 2006; Chen et al., 2014). In contrast, deeper placements favored ammonium (NH₄⁺-N) retention, possibly due to limited oxygen penetration, which restricts nitrification in anaerobic condition (Pereira et al., 2025 ). The highest NH₄⁺-N levels observed with ash-amended treatments at depth suggest that ash contributes to this retention by moderating pH and potentially inhibiting nitrifiers under alkaline conditions. In agreement with Liu et al. ( 2024 ), high pH conditions have been shown to alter microbial structure and enzymatic activity, reducing the rate of nitrification. 3.4 Interactive effects of manure type and depths on manure quality in open pits Organic carbon content varied significantly across treatments (p = 0.0004), reflecting the influence of both manure type and depth. The highest Organic carbon concentration (5.67 ± 0.67%) was observed in cattle manure at 50 cm, followed by goat manure at 50 cm (4.76 ± 0.37%). Compared to surface storage (0 cm), OC increased by 1.24% in cattle and 1.03% in goat manure at 50 cm. The result corroborates the findings of Fulton-Smith et al. ( 2024 ), who also reported intermediate depth of 50 cm supports better carbon stabilization, likely due to moderated oxygen exposure and microbial activity conducive to humification (L. Zhou et al., 2025 ). Similarly, Zhou et al. ( 2025 ) found that organic carbon accumulation at mid-depth may result from reduced carbon oxidation due to partial oxygen limitation and lower disturbance, enhancing microbial retention of carbon in more stable organic forms . NO₃⁻-N levels also shown treatment-based difference, with cattle manure at surface depth 0 cm showing higher concentrations than at 100 cm. A reduction of 0.54 mg kg − 1 was noted from 0 cm to 100 cm in cattle manure, indicating decreased nitrification with depth. Goat manure showed a similar decline of 0.38 mg/kg between the same depths. The decline in nitrate levels with depth may be attributed to limited aerobic zones for nitrification and potential leaching losses in open pits, especially in permeable soils or during rainy seasons as was also reported by Ramaswamy et al. ( 2010 ) . NH₄⁺-N concentrations were generally higher in goat manure at 100 cm (3.52 ± 0.21 mg/kg) than at the surface (2.76 ± 0.33 mg kg − 1 ), reflecting an increase of 0.76 mg kg − 1 . In cattle manure, the increase was slightly lower at 0.62 mg/kg between the surface and 100 cm. The increase in NH₄⁺-N with depth suggests limited volatilization losses due to reduced air contact. This supports findings by Eckardt et al. ( 2025 ), who reported that deeper storage environments preserve ammonium by minimizing ammonia emission pathways. Total Nitrogen varied across treatments with the highest concentration (0.85 ± 0.04%) found in cattle manure at 100 cm, representing an increase of 0.37% compared to the lowest TN recorded in goat manure at surface (0.48 ± 0.03%). Enhanced TN levels in deeper pits may be a result of minimized nitrogen losses through volatilization and leaching, as well as slower decomposition rates that promote nitrogen retention in organic form (Zhu et al., 2025 ). 3.5 Effects of different manure treatments on soil properties Moisture content varied significantly across treatment (Table 3 ) ranged from 17.08% in T1 (control) to 23.05% in T6 (goat manure covered pit). Treatments with manure amendments generally improved moisture retention compared to the control. Specifically, T6 recorded the highest value (23.05%), followed by T4 (22.02%) and T5 (21.30%), all showing improved capacity to retain water near the surface. Treatments T2 (20.58%) and T7 (19.71%) also outperformed the control, while T3 (18.08%) was only slightly higher than T1. At the 10–20 cm depth, a similar trend was observed, with moisture content values increasing across treatments. The highest value (29.80%) was again recorded in T6, while the control (24.00%) remained the lowest. Covering manure during decomposition likely preserves more organic matter and nutrients, which upon application improve soil aggregation and increase porosity. This in turn enhances soil water-holding capacity by improving capillary water retention (Akmal et al., 2023). At the 10–20 cm depth, moisture values were consistently higher than the topsoil. This may be attributed to reduced evapotranspiration losses and enhanced percolation of water into the subsurface layers, especially where manure improved soil structure. Similar findings have been reported by (Gorooei et al., 2023 ), who noted that organic amendments increased soil infiltration and water retention in semi-arid cropping systems. Bulk density was significantly lower at 0–10 cm than at 10–20 cm in most treatments, with T6 recording the lowest value (1.02 g/cm³). In contrast, treatments like T5 and T3 showed relatively high bulk densities even at surface level. Lower bulk density at the top layer indicates improved porosity and aeration resulting from organic manure decomposition. As depth increases, compaction from overburden soil and lower organic matter content contribute to increased density. In agreement with Guo et al. ( 2016 ), application of organic manures decreases soil bulk density, particularly at surface layers, due to enhanced aggregation and microbial activity. Table 3 Mean soil physical parameters ± standard error under management practices and depths interactions Treatment 0–10 cm depth 10–20 cm depth Moisture content (%) Bulk density Moisture content (%) Bulk density T1 17.08 ± 1.08 ab 1.19 ± 0.12 ab 24.00 ± 1.06 1.11 ± 0.14 T2 20.58 ± 0.65 ab 1.09 ± 0.04 b 27.00 ± 0.55 1.15 ± 0.07 T3 18.08 ± 0.90 ab 1.18 ± 0.10 ab 25.35 ± 1.14 1.20 ± 0.26 T4 22.02 ± 0.53 ab 1.16 ± 0.17 ab 29.45 ± 0.94 1.19 ± 0.13 T5 21.30 ± 0.93 b 1.38 ± 0.04 a 28.04 ± 0.56 1.20 ± 0.26 T6 23.05 ± 1.18 a 1.02 ± 0.04 b 29.80 ± 0.69 0.88 ± 0.10 T7 19.71 ± 1.26 ab 1.21 ± 0.09 ab 26.00 ± 1.11 1.13 ± 0.10 p value 0.01 0.02 0.49 0.29 CV (%) 21.21 8.2 23.29 14.93 Means with the same letter(s) within the same column are not significantly different at p ≤ 0.05. T1- Control; T2- Cattle manure (open pit); T3- Goat manure + Ash; T4- Cattle manure (covered pit); T5- Goat manure (open pit); T6- Goat manure (covered pit); T7- Cattle manure + Ash. 3.6: Effects of the treatments on soil mineral N Effects of management practices and soil depths on ammonium and nitrate concentrations ( Table 5 ) shows no significant differences in ammonium-N concentrations at either the top (0–10 cm; p = 0.481) or subsoil (10–20 cm; p = 0.106). Similarly, nitrate-N at 0–10 cm (p = 0.33) was not significantly influenced by the treatments. However, nitrate-N at 10–20 cm depth (p = 0.01) showed a significant treatment effect. Goat manure stored in covered pits (T6) had significantly lower subsoil nitrate (0.13 ± 0.14,) compared with cattle manure in open or covered pits (T2 and T4; 0.47 ± 0.15 and 0.47 ± 0.03, respectively), while other treatments were statistically similar to the control. The results indicate that nitrate dynamics, particularly at subsoil depth, are more responsive to manure type and storage method than ammonium dynamics. From a management perspective, goat manure stored in covered pits appears to lower subsoil nitrate accumulation and could help mitigate leaching risks, especially when combined with best practices such as incorporation and synchronizing application with crop demand (Otieno et al., 2024 ). The lack of consistent effects from ash-amended treatments (goat manure plus ash and cattle manure plus ash T3, T7) suggests that, under these soil conditions, ash did not substantially alter N mineralization and nitrification pathways (Koivula et al., 2004 ). Similar observations were made by Shakoor et al. (2021) who noted that wood ash can increase soil pH and sometimes enhance N transformations, its influence is context-specific and may require higher doses or longer observation periods to detect. 3.8 Effect of Different Manure Management Treatments on Soil pH The results show a significant difference across all treatments (Fig. 3 ). The control treatment (T1) consistently exhibited the lowest soil pH across both depths, indicating a more acidic soil environment relative to the amended treatments. At the 0–10 cm depth, T1 was significantly lower than T3, moderately lower than treatments such as T2, T4, T5, and T7. This suggests that organic treatments, particularly those represented by T3, were effective in raising soil pH compared to the untreated control. At the 10–20 cm depth, the control (T1) also had lower pH values than T3 and especially T7, indicating that the treatments not only influenced top soil but also had a measurable effect in the subsoil. These findings are consistent with previous studies showing that organic amendments such as farmyard manure, compost, and ash can increase soil pH by supplying basic cations (Ca²⁺, Mg²⁺, K⁺, Na⁺) and enhancing buffering capacity, thereby neutralizing soil acidity. Similarly, Liu et al. ( 2020 ), reported that manure application raised significantly raised pH compared to soils without amendments, with effects most evident in topsoil but also extending into deeper horizons under conditions of leaching and incorporation. However, the magnitude of pH change depends on the type and quality of the amendment as well as the baseline soil properties, since organic amendments with high nitrogen content can sometimes promote acidification through nitrification processes if not buffered by sufficient base cations (Das et al., 2023 ). 3.9 Effect of Different Manure Management Treatments on Soil electrical conductivity There is a significant difference across all the treatments (Fig. 4 ), results indicate that electrical conductivity (EC) was consistently lowest in the control treatment (T1) at both depths, highlighting the limited soluble salt content in untreated soils. At the 0–10 cm depth, T1 (Control) recorded significantly lower EC values compared to amended treatments such as T3 (goat manure) and T7 (cattle manure plus ash), which exhibited the highest EC levels. Intermediate treatments (T2, T4, T5, and T6) indicating modest but significant increases relative to the control. At the 10–20 cm depth, a similar pattern was observed: the control (T1) showed the lowest EC, while T7 recorded the highest, with values more than six times greater than the control. Other amendments (T2, T3, T4, T5, and T6,) were elevated compared to T1 but not statistically different from each other, suggesting that the strongest salinity effect was linked to T7. These differences demonstrate that organic amendments, particularly those rich in mineral salts or ash residues, can significantly increase soil electrical conductivity compared to untreated control soils. The rise in EC is largely attributed to the addition of exchangeable base cations (Ca²⁺, Mg²⁺, K⁺, Na⁺) and soluble anions (Cl⁻, SO₄²⁻, HCO₃⁻) that enhance ionic strength in the soil solution(Rayne & Aula, 2020 ). Ash-based treatments, such as T3 and T7, are known to contain high levels of soluble salts and carbonates, which explains their strong effect in elevating EC, consistent with earlier findings that wood ash can raise EC significantly due to its mineral content (Borase et al., 2020 ). Elevated EC following manure application has also been widely reported, with studies showing that continuous inputs of organic amendments increase soluble salt concentrations, particularly in the upper soil layers where organic matter decomposition releases ions. 4. Conclusion This study underscores the critical influence of manure management practices and sampling depth on key nutrient dynamics such as organic carbon (OC), nitrate-nitrogen (NO₃⁻-N), ammonium-nitrogen (NH₄⁺-N), and total nitrogen (TN). The findings reveal that covered pit systems, particularly at greater depths (100 cm), consistently preserve higher concentrations of essential nutrients compared to open pits. This suggests that limiting exposure to oxygen, rainfall, and temperature variations enhances the biochemical stability and fertilizing value of manure. The findings also underscore the role of organic and ash-based inputs in enhancing soil fertility by supplying base cations, neutralizing acidity, and enriching the soil solution with soluble salts. However, the magnitude of these changes varied with amendment type, highlighting the importance of balancing input quality and quantity to achieve soil improvement without adverse salinity build-up. This aligns with previous studies that emphasize the dual role of manures and ash as both pH-buffering and conductivity-enhancing agents, with implications for sustainable soil management in acidic and nutrient-depleted soils Declarations Acknowledgement The authors acknowledge the management of Samburu County Government for providing financial resources for the experimental fields and the technicians for managing the site and aiding in data collection. Funding This research was supported by the Samburu County Government through a postgraduate sponsorship for Master's studies. The authors gratefully acknowledge their financial and institutional support, which made this work possible. Authors’ Contributions Patrick Lpimari Lesharana: Data analysis, literature review and writing, Erick Oduor Otieno, Mwende Ngie: Supervision, Review and editing, Joseph P. Gweyi: Supervision, Review and Editing, Data analysis, review and editing. Ethical Approval This is not applicable. Consent to Participate This is not applicable. Consent to Publish This is not applicable. Competing Interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Data Availability Statement Data will be made available upon request. References Borase DN, Nath CP, Hazra KK, Senthilkumar M, Singh SS, Praharaj CS, Singh U, Kumar N (2020) Long-term impact of diversified crop rotations and nutrient management practices on soil microbial functions and soil enzymes activity. Ecol Ind 114:106322. https://doi.org/https://doi.org/10.1016/j.ecolind.2020.106322 Das S, Liptzin D, Maharjan B (2023) Long-term manure application improves soil health and stabilizes carbon in continuous maize production system. Geoderma 430:116338. https://doi.org/https://doi.org/10.1016/j.geoderma.2023.116338 Duan Y, Yang J, Awasthi MK, Pandey A, Li H (2023) Innovations in design and operation of aeration devices for composting and vermicomposting. In A. Pandey, M. Awasthi, & Z. B. T.-C. D. in B. and B. Zhang (Eds.), Current Developments in Biotechnology and Bioengineering (pp. 57–81). Elsevier. https://doi.org/https://doi.org/10.1016/B978-0-323-91874-9.00006-1 Eckardt M, Seidel A-K, Säger S, Simat TJ (2025) An alternative approach for compliance testing of food and skin contact silicone elastomers by specific determination of volatile cyclic siloxane oligomers via GC-FID. Talanta 283:127145. https://doi.org/https://doi.org/10.1016/j.talanta.2024.127145 Fang X, Harris SJ, Leitner SM, Butterbach-Bahl K, Conz RF, Merbold L, Dannenmann M, Oyugi A, Liu S, Zou J, Six J, Barthel M (2024) Mechanisms behind high N2O emissions from livestock enclosures in Kenya revealed by dual-isotope and functional gene analyses. Soil Biol Biochem 196(June):109505. https://doi.org/10.1016/j.soilbio.2024.109505 FAO (2019) World Food and Agriculture Statistical Pocketbook Fulton-Smith S, Even R, Cotrufo MF (2024) Depth impacts on the aggregate-mediated mechanisms of root carbon stabilization in soil: Trade-off between MAOM and POM pathways. Geoderma 452:117078. https://doi.org/10.1016/j.geoderma.2024.117078 Gomez-Munoz B, Larsen JD, Bekiaris G, Scheutz C, Bruun S, Nielsen S, Jensen LS (2017) Nitrogen mineralisation and greenhouse gas emission from the soil application of sludge from reed bed mineralisation systems. J Environ Manage 203:59–67. https://doi.org/10.1016/j.jenvman.2017.07.042 Gorooei A, Aynehband A, Rahnama A, Gaiser T, Kamali B (2023) Cropping systems and agricultural management strategies affect soil organic carbon dynamics in semi-arid regions. Front Sustainable Food Syst 6:200029. https://doi.org/10.3389/fsufs.2022.1016000 Guo L, Wu G, Li Y, Li C, Liu W, Meng J, Liu H, Yu X, Jiang G (2016) Effects of cattle manure compost combined with chemical fertilizer on topsoil organic matter, bulk density and earthworm activity in a wheat–maize rotation system in Eastern China. Soil Tillage Res 156:140–147. https://doi.org/https://doi.org/10.1016/j.still.2015.10.010 Huang J, Duan Y, hua, Xu M, gang, Zhai L, mei, Zhai X, bo, Wang Bren, Zhang Y, zhu, Gao S, duan, Sun N (2017) Nitrogen mobility, ammonia volatilization, and estimated leaching loss from long-term manure incorporation in red soil. J Integr Agric 16:2082–2092. https://doi.org/10.1016/S2095-3119(16)61498-3 Islam SMM, Gaihre YK, Islam MN, Jahan A, Sarkar MAR, Singh U, Islam A, Al Mahmud A, Akter M, Islam MR (2024) Effects of integrated nutrient management and urea deep placement on rice yield, nitrogen use efficiency, farm profits and greenhouse gas emissions in saline soils of Bangladesh. Sci Total Environ 909:168660. https://doi.org/10.1016/j.scitotenv.2023.168660 Jaetzold R, Schmidt H, Hornetz B, Shisanya C (2007) Farm management Handbook of Kenya. Natural conditions and farm management information. Part C- East Kenya. Subpart C1 - Eastern Province: Vol. II Koivula N, Räikkönen T, Urpilainen S, Ranta J, Hänninen K (2004) Ash in composting of source-separated catering waste. Bioresour Technol 93:291–299. https://doi.org/https://doi.org/10.1016/j.biortech.2003.10.025 Li M-X, He X-S, Tang J, Li X, Zhao R, Tao Y-Q, Wang C, Qiu Z-P (2021) Influence of moisture content on chicken manure stabilization during microbial agent-enhanced composting. Chemosphere 264:128549. https://doi.org/https://doi.org/10.1016/j.chemosphere.2020.128549 Liu Q, Jing W, Yang W, Huang M, Lu P, Hu D (2024) Green manure (Raphanus stativus L.) alters soil microbial structure and promotes acetochlor degradation. Arab J Chem 17:106017. https://doi.org/10.1016/j.arabjc.2024.106017 Liu S, Pu S, Deng D, Huang H, Yan C, Ma H, Razavi BS (2020) Comparable effects of manure and its biochar on reducing soil Cr bioavailability and narrowing the rhizosphere extent of enzyme activities. Environ Int 134:105277. https://doi.org/https://doi.org/10.1016/j.envint.2019.105277 McCullough CD (2024) The Importance of Nitrate Dynamics in Mine Pit Lakes of Drier Regions. Mine Water Environ 43:231–254. https://doi.org/10.1007/s10230-024-00987-1 Miner GL, Delgado JA, Ippolito JA, Stewart CE, Manter DK, Grosso SJ, Del, Floyd BA (2020) Assessing manure and inorganic nitrogen fertilization impacts on soil health, crop productivity, and crop quality in a continuous maize agroecosystem. J Soil Water Conserv 75:1–18. https://doi.org/10.2489/jswc.2020.00148 Mubarak A, Gali EA, ., Mohamed A, ., Steffens D, Awadelkarim A (2010) Nitrogen Mineralization from Five Manures as Influenced by Chemical Composition and Soil Type. Commun Soil Sci Plant Anal 41:37–41. https://doi.org/10.1080/00103624.2010.495802 Otieno EO, Lenga FK, Mburu DM, Kiboi MN, Fliessbach A, Ngetich FK (2024) Combined inorganic and organic fertilizers improved soil microbial biomass and nitrogen dynamics in Upper Eastern region of Kenya. Geoderma Reg 39:e00869. https://doi.org/10.1016/j.geodrs.2024.e00869 Otieno EO, Mburu DM, Ngetich FK, Kiboi MN, Fliessbach A, Lenga FK (2023) Effects of different soil management strategies on fertility and crop productivity in acidic nitisols of Central Highlands of Kenya. Environ Challenges 11:100683. https://doi.org/10.1016/j.envc.2023.100683 Pereira Á, Lemus J, Navarro P, Palomar J (2025) One-pot integrated CO2 and NH3 capture and utilization using ionic liquids towards ammonium carbamate. Chem Eng J 521:166708. https://doi.org/10.1016/j.cej.2025.166708 Ramaswamy J, Prasher SO, Patel RM, Hussain SA, Barrington SF (2010) The effect of composting on the degradation of a veterinary pharmaceutical. Bioresour Technol 101:2294–2299. https://doi.org/https://doi.org/10.1016/j.biortech.2009.10.089 Rayne N, Aula L (2020) Livestock manure and the impacts on soil health: A review. Soil Syst 4:1–26. https://doi.org/10.3390/soilsystems4040064 Shah A, Huang J, Han T, Khan MN, Tadesse KA, Daba NA, Khan S, Ullah S, Sardar MF, Fahad S, Zhang H (2024) Impact of soil moisture regimes on greenhouse gas emissions, soil microbial biomass, and enzymatic activity in long-term fertilized paddy soil. Environ Sci Europe 36:120. https://doi.org/10.1186/s12302-024-00943-4 UNICEF Report (2018) UNICEF Kenya Humanitarian Situation Report, 20 February 2017 . December , 1–9. https://www.unicef.org/appeals/files/UNICEF_Kenya_Humanitarian_SitRep_20_Feb_2017.pdf Wang L, Wen X, Deng Y, Wei Z, Li J, Song C (2025) The microhabitat regulation of moisture - ventilation mediated microbial carbon metabolism in response to humic acid formation during chicken manure and food waste composting. J Environ Manage 389:126048. https://doi.org/https://doi.org/10.1016/j.jenvman.2025.126048 Zhao S, Schmidt S, Qin W, Li J, Li G, Zhang W (2020) Towards the circular nitrogen economy – A global meta-analysis of composting technologies reveals much potential for mitigating nitrogen losses. Sci Total Environ 704:135401. https://doi.org/https://doi.org/10.1016/j.scitotenv.2019.135401 Zhou L, Wang Z, Li P, Sa R, Wang Z, Wang N, Xie Y, Yang X (2025) Microbial inoculation influences bacterial and autotrophic community assembly in cow dung–cotton straw composting to promote carbon sequestration and humification. Environ Technol Innov 39:104290. https://doi.org/10.1016/j.eti.2025.104290 Zhou X, Manna B, Lyu B, Singhal N (2025) Linking oxygen-induced oxidative stress to resource recovery by enhancing the production of extracellular polymeric substances in activated sludge microbial communities. Water Res 286:124238. https://doi.org/10.1016/j.watres.2025.124238 . Contents Zhu J, Xia S, Niu H, Xu J, Wang Y, Yu X, Huang L, Zhang K, Wang Y, Zeng L, Li Q, Li L (2025) Volatile organic compounds from typical industries in North China Plain: emissions, air pollution contribution, health risks, and policy implications. Environ Int 202:109673. https://doi.org/https://doi.org/10.1016/j.envint.2025.109673 Zornoza R, Moreno-Barriga F, Acosta JA, Muñoz MA, Faz A (2016) Stability, nutrient availability and hydrophobicity of biochars derived from manure, crop residues, and municipal solid waste for their use as soil amendments. Chemosphere 144:122–130. https://doi.org/https://doi.org/10.1016/j.chemosphere.2015.08.046 Zougmoré R, Partey S, Ouédraogo M, Omitoyin B, Thomas T, Ayantunde A, Ericksen P, Said M, Jalloh A (2016) Toward climate – smart agriculture in West Africa: a review of climate change impacts, adaptation strategies and policy developments for the livestock, fishery and crop production sectors. Agric Food Secur 1–16. https://doi.org/10.1186/s40066-016-0075-3 Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 1 posted 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7545517","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":510872352,"identity":"94d7a22b-1da5-4066-ab03-2064390e7a83","order_by":0,"name":"Patrick Lpimari Lesharana","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA4UlEQVRIiWNgGAWjYDACdgYGZgiL+QCQkJAhrIUZroUtAaSFhxQtPAZgkqAOc2bmw58Lau7Jm7Of+fzqRo0FDwP74aMb8GmxbGZLk55xrNhwZ0/uNuucY0CH8aSl3cCnxeAwjxkzD1sC44YDuduMc9iAWiR4zAho4f/8medfgv2G82+eGef8I0oLD4M0b1tC4oYbOcyPc9uI0AL0i5k0b19C8oYbz8yYc/skeNgI+cWcvfnxZ55vCbYbzic//pzzrU6On/3wMfwOQ2KzSYBJfMrRtTB/IKR6FIyCUTAKRiYAABU1Q87ak5rEAAAAAElFTkSuQmCC","orcid":"","institution":"Kenyatta University","correspondingAuthor":true,"prefix":"","firstName":"Patrick","middleName":"Lpimari","lastName":"Lesharana","suffix":""},{"id":510872353,"identity":"307a696e-90e8-4afa-8e37-ee21952e129c","order_by":1,"name":"Erick Oduor Otieno","email":"","orcid":"https://orcid.org/0000-0002-3832-0494","institution":"Kenyatta University","correspondingAuthor":false,"prefix":"","firstName":"Erick","middleName":"Oduor","lastName":"Otieno","suffix":""},{"id":510872354,"identity":"c2f95f55-ee54-4799-9bdd-355149787270","order_by":2,"name":"Mwende Ngie","email":"","orcid":"","institution":"Kenyatta University","correspondingAuthor":false,"prefix":"","firstName":"Mwende","middleName":"","lastName":"Ngie","suffix":""},{"id":510872355,"identity":"c87c4c18-9ba2-4048-8804-e9033037f4b3","order_by":3,"name":"Joseph Patrick Gweyi-Onyango","email":"","orcid":"","institution":"Kenyatta University","correspondingAuthor":false,"prefix":"","firstName":"Joseph","middleName":"Patrick","lastName":"Gweyi-Onyango","suffix":""}],"badges":[],"createdAt":"2025-09-05 15:21:34","currentVersionCode":1,"declarations":{"humanSubjects":false,"vertebrateSubjects":false,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":false,"humanSubjectConsent":false,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":false},"doi":"10.21203/rs.3.rs-7545517/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7545517/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":90876575,"identity":"5bd7864e-ebb6-44b4-9a08-845f55a0c347","added_by":"auto","created_at":"2025-09-09 09:01:18","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":127393,"visible":true,"origin":"","legend":"\u003cp\u003eMean (a) organic C, (b) total N, (c) nitrate-N, and (d) ammonium-N under the interaction of manure type and depth. Means with the same letter(s) on the bars are not significantly different at p≤0.05.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7545517/v1/4b62a15615e721d6a8903276.png"},{"id":90875575,"identity":"19654d81-d484-45be-8c0c-82ded1523da5","added_by":"auto","created_at":"2025-09-09 08:53:20","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":103737,"visible":true,"origin":"","legend":"\u003cp\u003eMean (a) organic C, (b) total N, (c) nitrate-N, and (d) ammonium-N under the interaction of manure type and depth. Means with the same letter(s) on the bars are not significantly different at p≤0.05.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7545517/v1/ec00aa2452b930065c327fc5.png"},{"id":90875545,"identity":"91b9c506-d734-4c65-9ba3-878c247fc82d","added_by":"auto","created_at":"2025-09-09 08:53:19","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":58810,"visible":true,"origin":"","legend":"\u003cp\u003eEffects of management practices and soil depths on \u003cem\u003eNH\u003c/em\u003e4\u003csup\u003e=\u003c/sup\u003e-N and \u003cem\u003eNO\u003c/em\u003e\u003csup\u003e-\u003c/sup\u003e\u003cem\u003eN\u003c/em\u003e concentrations\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7545517/v1/2473b71dc861e0eea2e10091.png"},{"id":90875515,"identity":"68731561-1b3b-4c72-9b63-d6299ef78bc9","added_by":"auto","created_at":"2025-09-09 08:53:17","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":51440,"visible":true,"origin":"","legend":"\u003cp\u003eMeans with the same letter(s) within the same column are not significantly different at p≤0.05. T1- Control; T2- Cattle manure (open pit); T3- Goat manure + Ash; T4- Cattle manure (covered pit); T5- Goat manure (open pit); T6- Goat manure (covered pit); T7- Cattle manure + Ash.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-7545517/v1/0d2634e5448290b61bb2d185.png"},{"id":90875569,"identity":"f251da89-2b3c-4bba-9e2b-433bfc30aff8","added_by":"auto","created_at":"2025-09-09 08:53:20","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":54066,"visible":true,"origin":"","legend":"\u003cp\u003eMeans with the same letter(s) within the same column are not significantly different at p≤0.05. T1- Control; T2- Cattle manure (open pit); T3- Goat manure + Ash; T4- Cattle manure (covered pit); T5- Goat manure (open pit); T6- Goat manure (covered pit); T7- Cattle manure + Ash.\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-7545517/v1/c64d03d54764517d70b9a2c0.png"},{"id":90877775,"identity":"bd5a5e8d-0790-4e11-89b1-bbc2ed2a651e","added_by":"auto","created_at":"2025-09-09 09:09:18","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1448668,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7545517/v1/4ab26b86-6681-4d0f-af80-9ff3a371a99d.pdf"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003e\u003cstrong\u003eOptimizing Cattle and Goat Manure Quality in Semi-arid Agrozone to Improve Fertility Status of Fragile Soils of Samburu County, Kenya\u003c/strong\u003e\u003c/p\u003e","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eIncreasing global population contributes to soil fertility depletion leading to food security challenges (FAO, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). More food demands have resulted in the expansion of intensive livestock production, leading to the production of huge amounts of animal manure that pose a severe environmental concern. Balancing the trade-off between increased livestock herds and protecting soil fertility integrity is crucial (Rayne \u0026amp; Aula, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2020\u003c/span\u003e).. Manure produced by the livestock manure can be harnessed to enhance soil fertility for crop production particularly in arid and semi-arid (ASAL) regions where pastoralism is the mainstay economic activity (Fang et al., \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Zougmor\u0026eacute; et al., \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e2016\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe need to attain manure management practices that are environmentally friendly has called for the adaptation of actions to improve its sustainable production worldwide (Miner et al., \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; Mubarak et al., \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2010\u003c/span\u003e). Additionally, the advancements in the livestock industry are increasing the importance of suitable manure management systems and practices. Nevertheless, a majority of farmers, particularly in sub-Sahara Africa (SSA), do not practice the recommended manure management strategies leading to significant nutrient losses through leaching, run-off and volatilization, and increased greenhouse gases emissions. Consequently, there has not been the desired improvement in soils amended with the manure (Miner et al., \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2020\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe inadequate land area for proper manure management has been reported to be one of the pertinent challenges among smallholder farmers (Duan et al., \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Islam et al., \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). As a result, livestock manure has become a public health (Zhao et al., \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e2020\u003c/span\u003e) and environmental menace. Moreover, manure may cause soil acidification, contamination of ground and surface water, and greenhouse gas emission (Borase et al., \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2020\u003c/span\u003e) if not well managed. It is, therefore, imperative to promote sustainable manure management strategies, especially in the fragile ASAL soils.\u003c/p\u003e\u003cp\u003eArid and semi-arid regions are likely to play a crucial role in food security due human population and climate change pressures. However, ASAL soils are fragile and could be further degraded. It is important that researchers leverage locally produced manure to build the resilience of these soils (Fang et al., \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Guo et al., \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). For instance, storage strategies are crucial in enhancing the quality of manure and its impact on soil fertility. Despite this, knowledge of the impact of storage strategies on manure quality and its impact on soil chemical characteristics are not well established, especially in the fragile soils of ASAL regions. The current study hypothesized that storage strategies impact manure quality and soil chemical characteristics of ASAL soils. Therefore, the aim of this study was to evaluate the effect of different management strategies on manure quality and chemical properties of ASAL soils in Samburu County.\u003c/p\u003e"},{"header":"2. Materials and methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003e2.1 Study site\u003c/h2\u003e\u003cp\u003eThe experimental carried out in Ngari location, Maralal ward (1.079782\u0026deg; N latitude and 36.713163\u0026deg; E), within Samburu County. The site is located in arid and semiarid regions of Kenya characterized by low rainfall patterns and high temperatures. It experiences bimodal rainfall between March (long rains) and October (short rains), receiving an average annual rainfall of 600\u0026ndash;1200 mm. The monthly minimum and maximum temperatures are 22\u0026deg;C and 30\u0026deg;C, respectively, as well as the mean relative humidity of 80%. Soils in the county are classified as Ferric Acrisols (Jaetzold et al., \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2007\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe dominant economic activity in the area is pastoralism, which supports the livelihoods of over 80% of the population. However, significant livestock populations, including cattle, goats, sheep, camels, and donkeys, which are not only sources of income but also contribute substantially to manure production. Livestock keeping is both a cultural and economic cornerstone for the Samburu community. In addition to livestock rearing, small-scale subsistence farming is practiced in areas with slightly higher rainfall and access to water, such as the Maralal escarpment (UNICEF Report, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2018\u003c/span\u003e).\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\u003ch2\u003e2.2 Experimental design\u003c/h2\u003e\u003cp\u003eSix separate compost pits were set; three for cattle manure and three for goat manure, with each pit capable of accommodating 1 ton of material. The composting pits used in the study measured 1 m \u0026times; 1 m in width and 1 m in depth, dimensions considered adequate to accommodate the volume of manure and allow for effective aeration and manual turning (Guo et al., \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). Turning of the compost was conducted manually using a garden fork to facilitate aerobic decomposition by enhancing oxygen penetration, redistributing moisture, and balancing microbial activity (Zhou et al., \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e2025\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eA total of six turnings were carried out throughout the composting period, which lasted approximately 90 days. The first turning was done on Day 7, followed by subsequent turnings at two-week intervals (Days 21, 35, 49, 63, and 77). The decision to adopt a biweekly turning schedule was informed by established composting guidelines which recommend turning every 10\u0026ndash;15 days for small-scale compost piles, especially under tropical or subtropical conditions, to maintain adequate oxygen supply and thermophilic activity (Ramaswamy et al., \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2010\u003c/span\u003e). A pit for cattle and goat manure were left open. Ash was added in the second cattle manure and goat manure pits at the rate 100 kg per ton. The third set of cattle manure and goat manure pits were covered using nylon slightly above the compost piles.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\u003ch2\u003e2.3 Design of field trials\u003c/h2\u003e\u003cp\u003eA field trial experiment was conducted using a randomized complete block design (RCBD) with 7 treatments and each replicated three times on plots measuring 1.5 m x 1.5 m separated by paths measuring 0.5 m, between replications, and 0.5 m between treatments. The following treatments were applied: Treatment 1: control; Treatment 2: cattle manure from open compost pit; Treatment 3: goat manure ash added compost pit; Treatment 4: cattle manure from covered compost pit; Treatment 5: goat manure from open compost pit; Treatment 6: Goat manure from covered pit; Treatment 7: cattle manure ash added compost pit.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec6\" class=\"Section2\"\u003e\u003ch2\u003e2.4 Determination of OC and N\u003c/h2\u003e\u003cp\u003eCompost samples were collected from 0 cm, 50 cm, and 100 cm depths from each pit, thoroughly mixed, and about 500 g subsamples were obtained, placed in zip locks, and transported to Kenyatta University laboratory in a cool-box fitted with ice-cubes. Soil organic carbon was determined by a Carbon Nitrogen (CN) Elemental Analyser. 2.5 g of air-dried soil were weighed into centrifuge tubes, 18 mL distilled water (DI) and 2 mL (0.2 M) K\u003csub\u003e2\u003c/sub\u003eMnO\u003csub\u003e4\u003c/sub\u003e added, shaken at 240 revolutions per minute for 2 min, tubes removed and allowed to settle for 10 min, thereafter 0.5 mL of the supernatant was taken and mixed with 49.5 mL of DI. From each sample, 200 \u0026micro;l aliquots were extracted and their concentrations read with a spectrophotometer set at a wavelength of 550 nm.\u003c/p\u003e\u003cp\u003eMineral N (NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e-N and NO\u003csub\u003e3\u003c/sub\u003e \u0026ndash;N) was determined based on the method adopted by Gomez-Munoz et al. (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2017\u003c/span\u003e). Approximately 5 g of oven-dried soil was placed in 100 ml shaking bottles. About 50 ml of 0.5 M K\u003csub\u003e2\u003c/sub\u003eSO4 was then added into the bottle and shaken on reciprocal shaker at 200 rmp for thirty minutes after which it was filtered using Whatman no. 42 filter papers (Otieno et al., \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). Ammonium N and NO\u003csub\u003e3\u003c/sub\u003e\u0026ndash;N were then determined using UV spectrophotometer at 655 nm and 419 nm, respectively. Soil texture was determined using the hydrometer method.\u003c/p\u003e\u003cp\u003eSoil bulk density and moisture content (SMC) were determined gravimetrically (Otieno et al., \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Fifteen (15) grams of soil samples were collected from 0\u0026ndash;20 cm using a core ring with a known volume for bulk density determination. The soil samples were oven-dried at 105\u0026deg;C for 24 h until constant weights were attained. Bulk density and SMC were then calculated using equations \u003cb\u003e1\u003c/b\u003e and \u003cb\u003e2\u003c/b\u003e.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Taba\" border=\"1\"\u003e\u003ccolgroup cols=\"2\"\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\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\text{B}\\text{u}\\text{l}\\text{k}\\:\\text{d}\\text{e}\\text{n}\\text{s}\\text{i}\\text{t}\\text{y}\\:\\left(\\text{g}\\:{cm}^{-3}\\right)=\\frac{\\text{S}\\text{o}\\text{i}\\text{l}\\:\\text{S}\\text{o}\\text{l}\\text{i}\\text{d}\\text{s}\\:\\left(\\text{M}\\text{s}\\right)}{\\text{T}\\text{o}\\text{t}\\text{a}\\text{l}\\:\\text{V}\\text{o}\\text{l}\\text{u}\\text{m}\\text{e}\\:\\text{o}\\text{f}\\:\\text{S}\\text{o}\\text{i}\\text{l}\\:\\left(\\text{V}\\text{t}\\right)}\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003e(1)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\text{G}\\text{r}\\text{a}\\text{v}\\text{i}\\text{m}\\text{e}\\text{t}\\text{r}\\text{i}\\text{c}\\:\\text{S}\\text{M}\\text{C}\\:\\left(\\text{%}\\right)=\\frac{\\left(\\text{T}\\text{o}\\text{t}\\text{a}\\text{l}\\:\\text{s}\\text{o}\\text{i}\\text{l}\\:\\text{m}\\text{a}\\text{s}\\text{s}\\left(\\text{M}\\text{t}\\right)-\\text{S}\\text{o}\\text{i}\\text{l}\\:\\text{s}\\text{o}\\text{l}\\text{i}\\text{d}\\text{s}\\left(\\text{M}\\text{s}\\right)\\right)}{\\text{S}\\text{o}\\text{i}\\text{l}\\:\\text{S}\\text{o}\\text{l}\\text{i}\\text{d}\\text{s}\\:\\left(\\text{M}\\text{s}\\right)}\\text{x}\\:100\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e(2)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\u003ch2\u003e2.5 Statistical analysis\u003c/h2\u003e\u003cp\u003eThe biophysical data were subjected to analysis of variance using R software. A post hoc analysis using HSD turkey at p\u0026thinsp;\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003e\u0026le;\u003c/span\u003e\u0026thinsp;0.05 were means were significantly different.\u003c/p\u003e\u003c/div\u003e"},{"header":"3. Results and Discussion","content":"\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e\u003ch2\u003e3.1 Interactive effects of management practices and depths on goat manure quality\u003c/h2\u003e\u003cp\u003eInteraction between management strategies and depth had significant effects on manure quality parameters (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The interaction between covered pits and 100 cm and 50 cm depths had significantly higher OC by 60 and 59% compared to open pits at 0 cm depth, respectively. Similarly, open pits at 50 and100 cm depths greatly improved OC by 52 and 42% relative to open pits at 0 cm. Compared at 0 cm, covered pits remarkably enhanced OC by 37% compared to the open pits. The increased OC under covered and deeper pits may be attributed to reduced volatilization and enhanced microbial activity under stable thermal and moisture conditions (Li et al., \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Similar obervations were made by Hao et al., 2004 who noted that oxygen regulation and moisture retention in covered systems favor carbon stabilization and humification processes.\u003c/p\u003e\u003cp\u003eThe management strategies significantly influenced the concentration of mineral nitrogen, including Nitrate \u0026ndash; N and Ammonium \u0026ndash; N. Covered pits at 50 cm depth recorded the highest Nitrate- N levels (188.0 ppm), followed by open pits at 100 cm (148.0 ppm), both significantly greater than open pits at 0 cm (57.1ppm). Covered pits foster aerobic zones conducive to nitrifier activity, leading to greater nitrate accumulation. Conversely, the low nitrate content in open pits at shallow depth may be due to nitrogen volatilization and leaching losses (McCullough, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2024\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eTotal Nitrogen (TN) also responded significantly (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) to the interaction of the management strategies and depth (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The total Nitrogen (0.71%) was recorded in the covered pits at 50 cm depth, marking a 173% increase compared to open pits at 0 cm (0.26%). Covered pits at 100 cm and 0 cm also showed increases of 123% and 123%, respectively. Open pits at 50 cm and 100 cm improved TN by 104% and 100%, respectively compared to open pits at 0 cm. These increases are likely due to better nitrogen conservation through reduced leaching, minimized ammonia volatilization, and the slower breakdown of nitrogen-rich compounds under covered, moisture-regulated conditions. These findings align with those of Zhao et al. (\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e2020\u003c/span\u003e), who emphasized the effectiveness of controlled composting environments in preserving nitrogen content during decomposition.\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\u003eMean goat manure quality parameters\u0026thinsp;\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003e\u0026plusmn;\u003c/span\u003e\u0026thinsp;standard error under management practices and depths interactions\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\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\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eManagement practice\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eDepths\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eOC (%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eNitrate-N (ppm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eAmmonium-N (ppm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eTN (%)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCovered pit\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3.63\u0026thinsp;\u0026plusmn;\u0026thinsp;0.23\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e70.6\u0026thinsp;\u0026plusmn;\u0026thinsp;3.4\u003csup\u003ecd\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e484\u0026thinsp;\u0026plusmn;\u0026thinsp;53.8\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.58\u0026thinsp;\u0026plusmn;\u0026thinsp;0.06\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOpen pit\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2.28\u0026thinsp;\u0026plusmn;\u0026thinsp;0.14\u003csup\u003ee\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e57.1\u0026thinsp;\u0026plusmn;\u0026thinsp;8.9\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e56\u0026thinsp;\u0026plusmn;\u0026thinsp;2.2\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.26\u0026thinsp;\u0026plusmn;\u0026thinsp;0.02\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCovered pit\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e50 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5.61\u0026thinsp;\u0026plusmn;\u0026thinsp;0.46\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e188.0\u0026thinsp;\u0026plusmn;\u0026thinsp;13.5\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e679\u0026thinsp;\u0026plusmn;\u0026thinsp;96.3\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.71\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOpen pit\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e50 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4.76\u0026thinsp;\u0026plusmn;\u0026thinsp;0.37\u003csup\u003ebc\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e69.5\u0026thinsp;\u0026plusmn;\u0026thinsp;16.9\u003csup\u003ecd\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e109\u0026thinsp;\u0026plusmn;\u0026thinsp;16.2\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.53\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCovered pit\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e100 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5.70\u0026thinsp;\u0026plusmn;\u0026thinsp;0.53\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e97.4\u0026thinsp;\u0026plusmn;\u0026thinsp;16.8\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e707\u0026thinsp;\u0026plusmn;\u0026thinsp;88.5\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.58\u0026thinsp;\u0026plusmn;\u0026thinsp;0.06\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOpen pit\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e100 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3.96\u0026thinsp;\u0026plusmn;\u0026thinsp;0.14\u003csup\u003ecd\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e148.0\u0026thinsp;\u0026plusmn;\u0026thinsp;13.5\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e197\u0026thinsp;\u0026plusmn;\u0026thinsp;9.0\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.52\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ep value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eMeans with the same letter(s) within the same column are not significantly different at p\u0026thinsp;\u0026le;\u0026thinsp;0.05, \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003e\u0026plusmn;\u003c/span\u003e = standard errors of the mean.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e\u003ch2\u003e3.2 Interactive effects of management practices and depths on cattle manure at different depths\u003c/h2\u003e\u003cp\u003eThe organic carbon (OC) content varied significantly with compost management strategy and depth (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The open pit at 0 cm recorded an OC content of 1.03%. In contrast, covered pits at 100 cm and 50 cm depths exhibited the highest OC values at 6.51% and 6.44%, representing 532% and 525% increases over the control. Similarly, the open pit at 50 cm recorded 5.67% OC, a 451% rise compared to the control. Open pit at 100 cm yielded 3.78%, an increase of 267%, while the covered pit at 0 cm had 0.75%, slightly lower (27% decrease) than the control.\u003c/p\u003e\u003cp\u003eThese results demonstrate that increasing composting depth substantially enhances OC accumulation, particularly in covered systems. The elevated OC observed under deep, covered pits may be attributed to reduced oxygen exposure and minimal physical disturbance, which limit organic matter degradation and carbon dioxide volatilization. Additionally, covering the compost moderates internal temperatures and retains moisture, thereby supporting microbial activity and humification. Similar findings were reported by Duan et al. (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2023\u003c/span\u003e), who found that reduced aeration and improved moisture regulation in covered compost piles enhance carbon retention. Wang et al. (\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2025\u003c/span\u003e) also noted that composting under controlled microclimatic conditions, such as in deeper or covered systems, leads to greater preservation of organic carbon by slowing down oxidative decomposition.\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\u003eMean cattle manure quality parameters\u0026thinsp;\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003e\u0026plusmn;\u003c/span\u003e\u0026thinsp;standard errors under management practices and depths interactions\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\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\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eManagement practice\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eDepths\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eOC (%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eNitrate -N (ppm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eAmmonium -N (ppm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eTN (%)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOpen pit\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.03\u0026thinsp;\u0026plusmn;\u0026thinsp;0.11\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e66.4\u0026thinsp;\u0026plusmn;\u0026thinsp;10.9\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e86\u0026thinsp;\u0026plusmn;\u0026thinsp;9.53\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.15\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCovered pit\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.75\u0026thinsp;\u0026plusmn;\u0026thinsp;0.02\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e59.6\u0026thinsp;\u0026plusmn;\u0026thinsp;7.55\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e76\u0026thinsp;\u0026plusmn;\u0026thinsp;13.40\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.16\u0026thinsp;\u0026plusmn;\u0026thinsp;0.05\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCovered pit\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e50 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6.44\u0026thinsp;\u0026plusmn;\u0026thinsp;0.52\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e68.6\u0026thinsp;\u0026plusmn;\u0026thinsp;3.46\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e287\u0026thinsp;\u0026plusmn;\u0026thinsp;30.3\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.71\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOpen pit\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e50 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5.67\u0026thinsp;\u0026plusmn;\u0026thinsp;0.67\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e83.2\u0026thinsp;\u0026plusmn;\u0026thinsp;7.33\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e141\u0026thinsp;\u0026plusmn;\u0026thinsp;6.7 0\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.44\u0026thinsp;\u0026plusmn;\u0026thinsp;0.05\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCovered pit\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e100 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6.51\u0026thinsp;\u0026plusmn;\u0026thinsp;0.52\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e75.0\u0026thinsp;\u0026plusmn;\u0026thinsp;6.98\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e349\u0026thinsp;\u0026plusmn;\u0026thinsp;4.45a\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.60\u0026thinsp;\u0026plusmn;\u0026thinsp;0.07\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOpen pit\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e100 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3.78\u0026thinsp;\u0026plusmn;\u0026thinsp;0.20\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e71.9\u0026thinsp;\u0026plusmn;\u0026thinsp;8.13\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e321\u0026thinsp;\u0026plusmn;\u0026thinsp;25.8\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.39\u0026thinsp;\u0026plusmn;\u0026thinsp;0.05\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ep value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.04\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eMeans with the same letter(s) within the same column are not significantly different at p\u0026thinsp;\u0026le;\u0026thinsp;0.05, \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003e\u0026plusmn;\u003c/span\u003e = standard errors of the mean.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\u003ch2\u003e3.3 Interactive effects of management practice and depths on goat and cattle manure\u003c/h2\u003e\u003cp\u003eThe goat and cattle manure treated with ash, across different depths (0 cm, 50 cm, and 100 cm), on organic carbon (OC), nitrate-nitrogen (NO₃⁻-N), ammonium-nitrogen (NH₄⁺-N), and total nitrogen (TN). Organic carbon was significantly influenced by treatment (p\u0026thinsp;=\u0026thinsp;0.007). The highest OC content was recorded in cattle manure treated with ash at 100 cm (6.05\u0026thinsp;\u0026plusmn;\u0026thinsp;0.62%), followed closely by the same treatment at 50 cm (5.78\u0026thinsp;\u0026plusmn;\u0026thinsp;0.21%). This represents an increase of 3.75% OC compared to the lowest value observed in open pit goat manure without ash treatment (2.30%).\u003c/p\u003e\u003cp\u003eComparing application at 0 cm in open pits without ash to deep placement of cattle manure treated with ash (100 cm), OC content increased by 3.75%. Similarly, in goat manure, OC rose from 2.3% at 0 cm to 3.9% at 100 cm with ash treatment an improvement of 1.6%. These increments highlight the effectiveness of both ash amendment and depth in preserving organic carbon. This aligns with Nzeyimana et al. (2021), who emphasized that deeper burial reduces carbon mineralization by limiting microbial access to oxygen. The role of ash in stabilizing OC likely stems from its alkaline pH, which buffers the compost environment, and its mineral content, which facilitates the formation of organo-mineral complexes that reduce microbial decomposition rates (Kumar et al., 2023).\u003c/p\u003e\u003cp\u003eNitrate-nitrogen (NO₃⁻-N) concentrations were generally higher in surface applications and declined with depth, particularly in goat manure treatments. The highest NO₃⁻-N level was observed in goat manure without ash at the surface (38.1\u0026thinsp;\u0026plusmn;\u0026thinsp;2.1 mg kg\u003csup\u003e-1\u003c/sup\u003e), which decreased by 17.5 mg kg\u003csup\u003e-1\u003c/sup\u003eat 100 cm depth (20.6\u0026thinsp;\u0026plusmn;\u0026thinsp;1.4 mg kg\u003csup\u003e-1\u003c/sup\u003e). Ammonium-nitrogen (NH₄⁺-N), in contrast, increased with depth, especially under ash-treated cattle manure, rising from 18.3\u0026thinsp;\u0026plusmn;\u0026thinsp;1.2 mg kg\u003csup\u003e-1\u003c/sup\u003eat 0 cm to 31.5\u0026thinsp;\u0026plusmn;\u0026thinsp;2.0 mg/kg at 100 cm a 13.2 mg kg\u003csup\u003e-1\u003c/sup\u003e increase.\u003c/p\u003e\u003cp\u003eTotal nitrogen (TN) followed a similar trend to OC. The highest TN (0.85\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04%) was measured in ash-treated cattle manure at 100 cm depth, representing an increase of 0.37% compared to the lowest TN recorded in untreated goat manure at the surface (0.48\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03%). The deeper placement of manure likely reduced nitrogen losses through volatilization and leaching, which are more pronounced in surface applied treatments exposed to rainfall and temperature fluctuations (Islam et al., \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). This result agrees with the finding of Huang et al. (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2017\u003c/span\u003e) who found that placement at 100 cm may also limit gaseous nitrogen losses by creating microenvironments with restricted aeration, thus slowing nitrification denitrification pathways and favoring nitrogen retention in organic and ammonium forms.\u003c/p\u003e\u003cp\u003eNitrogen dynamics reflected depth and treatment interactions. Top application at 0 cm exhibited higher nitrate (NO₃⁻-N) levels, likely due to increased nitrification under aerobic conditions, where oxygen availability supports the microbial oxidation of ammonium to nitrate (Subbarao et al., 2006; Chen et al., 2014). In contrast, deeper placements favored ammonium (NH₄⁺-N) retention, possibly due to limited oxygen penetration, which restricts nitrification in anaerobic condition (Pereira et al., \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2025\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe highest NH₄⁺-N levels observed with ash-amended treatments at depth suggest that ash contributes to this retention by moderating pH and potentially inhibiting nitrifiers under alkaline conditions. In agreement with Liu et al. (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2024\u003c/span\u003e), high pH conditions have been shown to alter microbial structure and enzymatic activity, reducing the rate of nitrification.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\u003ch2\u003e3.4 Interactive effects of manure type and depths on manure quality in open pits\u003c/h2\u003e\u003cp\u003eOrganic carbon content varied significantly across treatments (p\u0026thinsp;=\u0026thinsp;0.0004), reflecting the influence of both manure type and depth. The highest Organic carbon concentration (5.67\u0026thinsp;\u0026plusmn;\u0026thinsp;0.67%) was observed in cattle manure at 50 cm, followed by goat manure at 50 cm (4.76\u0026thinsp;\u0026plusmn;\u0026thinsp;0.37%). Compared to surface storage (0 cm), OC increased by 1.24% in cattle and 1.03% in goat manure at 50 cm. The result corroborates the findings of Fulton-Smith et al. (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2024\u003c/span\u003e), who also reported intermediate depth of 50 cm supports better carbon stabilization, likely due to moderated oxygen exposure and microbial activity conducive to humification (L. Zhou et al., \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e2025\u003c/span\u003e). Similarly, Zhou et al. (\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e2025\u003c/span\u003e) found that organic carbon accumulation at mid-depth may result from reduced carbon oxidation due to partial oxygen limitation and lower disturbance, enhancing microbial retention of carbon in more stable organic forms .\u003c/p\u003e\u003cp\u003eNO₃⁻-N levels also shown treatment-based difference, with cattle manure at surface depth 0 cm showing higher concentrations than at 100 cm. A reduction of 0.54 mg kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003ewas noted from 0 cm to 100 cm in cattle manure, indicating decreased nitrification with depth. Goat manure showed a similar decline of 0.38 mg/kg between the same depths. The decline in nitrate levels with depth may be attributed to limited aerobic zones for nitrification and potential leaching losses in open pits, especially in permeable soils or during rainy seasons as was also reported by Ramaswamy et al. (\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2010\u003c/span\u003e) .\u003c/p\u003e\u003cp\u003eNH₄⁺-N concentrations were generally higher in goat manure at 100 cm (3.52\u0026thinsp;\u0026plusmn;\u0026thinsp;0.21 mg/kg) than at the surface (2.76\u0026thinsp;\u0026plusmn;\u0026thinsp;0.33 mg kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e), reflecting an increase of 0.76 mg kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. In cattle manure, the increase was slightly lower at 0.62 mg/kg between the surface and 100 cm. The increase in NH₄⁺-N with depth suggests limited volatilization losses due to reduced air contact. This supports findings by Eckardt et al. (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2025\u003c/span\u003e), who reported that deeper storage environments preserve ammonium by minimizing ammonia emission pathways.\u003c/p\u003e\u003cp\u003eTotal Nitrogen varied across treatments with the highest concentration (0.85\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04%) found in cattle manure at 100 cm, representing an increase of 0.37% compared to the lowest TN recorded in goat manure at surface (0.48\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03%). Enhanced TN levels in deeper pits may be a result of minimized nitrogen losses through volatilization and leaching, as well as slower decomposition rates that promote nitrogen retention in organic form (Zhu et al., \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2025\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\u003ch2\u003e3.5 Effects of different manure treatments on soil properties\u003c/h2\u003e\u003cp\u003eMoisture content varied significantly across treatment (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e) ranged from 17.08% in T1 (control) to 23.05% in T6 (goat manure covered pit). Treatments with manure amendments generally improved moisture retention compared to the control. Specifically, T6 recorded the highest value (23.05%), followed by T4 (22.02%) and T5 (21.30%), all showing improved capacity to retain water near the surface. Treatments T2 (20.58%) and T7 (19.71%) also outperformed the control, while T3 (18.08%) was only slightly higher than T1.\u003c/p\u003e\u003cp\u003eAt the 10\u0026ndash;20 cm depth, a similar trend was observed, with moisture content values increasing across treatments. The highest value (29.80%) was again recorded in T6, while the control (24.00%) remained the lowest. Covering manure during decomposition likely preserves more organic matter and nutrients, which upon application improve soil aggregation and increase porosity. This in turn enhances soil water-holding capacity by improving capillary water retention (Akmal et al., 2023). At the 10\u0026ndash;20 cm depth, moisture values were consistently higher than the topsoil. This may be attributed to reduced evapotranspiration losses and enhanced percolation of water into the subsurface layers, especially where manure improved soil structure. Similar findings have been reported by (Gorooei et al., \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2023\u003c/span\u003e), who noted that organic amendments increased soil infiltration and water retention in semi-arid cropping systems.\u003c/p\u003e\u003cp\u003eBulk density was significantly lower at 0\u0026ndash;10 cm than at 10\u0026ndash;20 cm in most treatments, with T6 recording the lowest value (1.02 g/cm\u0026sup3;). In contrast, treatments like T5 and T3 showed relatively high bulk densities even at surface level. Lower bulk density at the top layer indicates improved porosity and aeration resulting from organic manure decomposition. As depth increases, compaction from overburden soil and lower organic matter content contribute to increased density. In agreement with Guo et al. (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2016\u003c/span\u003e), application of organic manures decreases soil bulk density, particularly at surface layers, due to enhanced aggregation and microbial activity.\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\u003eMean soil physical parameters\u0026thinsp;\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003e\u0026plusmn;\u003c/span\u003e\u0026thinsp;standard error under management practices and depths interactions\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\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\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eTreatment\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003e0\u0026ndash;10 cm depth\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e\u003cp\u003e10\u0026ndash;20 cm depth\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMoisture content (%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eBulk density\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\u003eBulk density\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eT1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e17.08\u0026thinsp;\u0026plusmn;\u0026thinsp;1.08\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.19\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e24.00\u0026thinsp;\u0026plusmn;\u0026thinsp;1.06\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.11\u0026thinsp;\u0026plusmn;\u0026thinsp;0.14\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eT2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e20.58\u0026thinsp;\u0026plusmn;\u0026thinsp;0.65\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.09\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e27.00\u0026thinsp;\u0026plusmn;\u0026thinsp;0.55\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.15\u0026thinsp;\u0026plusmn;\u0026thinsp;0.07\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eT3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e18.08\u0026thinsp;\u0026plusmn;\u0026thinsp;0.90\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.18\u0026thinsp;\u0026plusmn;\u0026thinsp;0.10\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e25.35\u0026thinsp;\u0026plusmn;\u0026thinsp;1.14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.20\u0026thinsp;\u0026plusmn;\u0026thinsp;0.26\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eT4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e22.02\u0026thinsp;\u0026plusmn;\u0026thinsp;0.53\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.16\u0026thinsp;\u0026plusmn;\u0026thinsp;0.17\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e29.45\u0026thinsp;\u0026plusmn;\u0026thinsp;0.94\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.19\u0026thinsp;\u0026plusmn;\u0026thinsp;0.13\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eT5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e21.30\u0026thinsp;\u0026plusmn;\u0026thinsp;0.93\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.38\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e28.04\u0026thinsp;\u0026plusmn;\u0026thinsp;0.56\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.20\u0026thinsp;\u0026plusmn;\u0026thinsp;0.26\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eT6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e23.05\u0026thinsp;\u0026plusmn;\u0026thinsp;1.18\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.02\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e29.80\u0026thinsp;\u0026plusmn;\u0026thinsp;0.69\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.88\u0026thinsp;\u0026plusmn;\u0026thinsp;0.10\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eT7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e19.71\u0026thinsp;\u0026plusmn;\u0026thinsp;1.26\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.21\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e26.00\u0026thinsp;\u0026plusmn;\u0026thinsp;1.11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.13\u0026thinsp;\u0026plusmn;\u0026thinsp;0.10\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ep value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.01\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.02\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.49\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.29\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCV (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e21.21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e8.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e23.29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e14.93\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eMeans with the same letter(s) within the same column are not significantly different at p\u0026thinsp;\u0026le;\u0026thinsp;0.05. T1- Control; T2- Cattle manure (open pit); T3- Goat manure\u0026thinsp;+\u0026thinsp;Ash; T4- Cattle manure (covered pit); T5- Goat manure (open pit); T6- Goat manure (covered pit); T7- Cattle manure\u0026thinsp;+\u0026thinsp;Ash.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e\u003ch2\u003e3.6: Effects of the treatments on soil mineral N\u003c/h2\u003e\u003cp\u003eEffects of management practices and soil depths on ammonium and nitrate concentrations (\u003cb\u003eTable\u0026nbsp;5\u003c/b\u003e) shows no significant differences in ammonium-N concentrations at either the top (0\u0026ndash;10 cm; p\u0026thinsp;=\u0026thinsp;0.481) or subsoil (10\u0026ndash;20 cm; p\u0026thinsp;=\u0026thinsp;0.106). Similarly, nitrate-N at 0\u0026ndash;10 cm (p\u0026thinsp;=\u0026thinsp;0.33) was not significantly influenced by the treatments. However, nitrate-N at 10\u0026ndash;20 cm depth (p\u0026thinsp;=\u0026thinsp;0.01) showed a significant treatment effect. Goat manure stored in covered pits (T6) had significantly lower subsoil nitrate (0.13\u0026thinsp;\u0026plusmn;\u0026thinsp;0.14,) compared with cattle manure in open or covered pits (T2 and T4; 0.47\u0026thinsp;\u0026plusmn;\u0026thinsp;0.15 and 0.47\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03, respectively), while other treatments were statistically similar to the control. The results indicate that nitrate dynamics, particularly at subsoil depth, are more responsive to manure type and storage method than ammonium dynamics. From a management perspective, goat manure stored in covered pits appears to lower subsoil nitrate accumulation and could help mitigate leaching risks, especially when combined with best practices such as incorporation and synchronizing application with crop demand (Otieno et al., \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). The lack of consistent effects from ash-amended treatments (goat manure plus ash and cattle manure plus ash T3, T7) suggests that, under these soil conditions, ash did not substantially alter N mineralization and nitrification pathways (Koivula et al., \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2004\u003c/span\u003e). Similar observations were made by Shakoor et al. (2021) who noted that wood ash can increase soil pH and sometimes enhance N transformations, its influence is context-specific and may require higher doses or longer observation periods to detect.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e\u003ch2\u003e3.8 Effect of Different Manure Management Treatments on Soil pH\u003c/h2\u003e\u003cp\u003eThe results show a significant difference across all treatments (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The control treatment (T1) consistently exhibited the lowest soil pH across both depths, indicating a more acidic soil environment relative to the amended treatments. At the 0\u0026ndash;10 cm depth, T1 was significantly lower than T3, moderately lower than treatments such as T2, T4, T5, and T7. This suggests that organic treatments, particularly those represented by T3, were effective in raising soil pH compared to the untreated control. At the 10\u0026ndash;20 cm depth, the control (T1) also had lower pH values than T3 and especially T7, indicating that the treatments not only influenced top soil but also had a measurable effect in the subsoil.\u003c/p\u003e\u003cp\u003eThese findings are consistent with previous studies showing that organic amendments such as farmyard manure, compost, and ash can increase soil pH by supplying basic cations (Ca\u0026sup2;⁺, Mg\u0026sup2;⁺, K⁺, Na⁺) and enhancing buffering capacity, thereby neutralizing soil acidity. Similarly, Liu et al. (\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2020\u003c/span\u003e), reported that manure application raised significantly raised pH compared to soils without amendments, with effects most evident in topsoil but also extending into deeper horizons under conditions of leaching and incorporation. However, the magnitude of pH change depends on the type and quality of the amendment as well as the baseline soil properties, since organic amendments with high nitrogen content can sometimes promote acidification through nitrification processes if not buffered by sufficient base cations (Das et al., \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2023\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec16\" class=\"Section2\"\u003e\u003ch2\u003e3.9 Effect of Different Manure Management Treatments on Soil electrical conductivity\u003c/h2\u003e\u003cp\u003eThere is a significant difference across all the treatments (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e4\u003c/span\u003e), results indicate that electrical conductivity (EC) was consistently lowest in the control treatment (T1) at both depths, highlighting the limited soluble salt content in untreated soils. At the 0\u0026ndash;10 cm depth, T1 (Control) recorded significantly lower EC values compared to amended treatments such as T3 (goat manure) and T7 (cattle manure plus ash), which exhibited the highest EC levels. Intermediate treatments (T2, T4, T5, and T6) indicating modest but significant increases relative to the control. At the 10\u0026ndash;20 cm depth, a similar pattern was observed: the control (T1) showed the lowest EC, while T7 recorded the highest, with values more than six times greater than the control. Other amendments (T2, T3, T4, T5, and T6,) were elevated compared to T1 but not statistically different from each other, suggesting that the strongest salinity effect was linked to T7.\u003c/p\u003e\u003cp\u003eThese differences demonstrate that organic amendments, particularly those rich in mineral salts or ash residues, can significantly increase soil electrical conductivity compared to untreated control soils. The rise in EC is largely attributed to the addition of exchangeable base cations (Ca\u0026sup2;⁺, Mg\u0026sup2;⁺, K⁺, Na⁺) and soluble anions (Cl⁻, SO₄\u0026sup2;⁻, HCO₃⁻) that enhance ionic strength in the soil solution(Rayne \u0026amp; Aula, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Ash-based treatments, such as T3 and T7, are known to contain high levels of soluble salts and carbonates, which explains their strong effect in elevating EC, consistent with earlier findings that wood ash can raise EC significantly due to its mineral content (Borase et al., \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Elevated EC following manure application has also been widely reported, with studies showing that continuous inputs of organic amendments increase soluble salt concentrations, particularly in the upper soil layers where organic matter decomposition releases ions.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e"},{"header":"4. Conclusion","content":"\u003cp\u003eThis study underscores the critical influence of manure management practices and sampling depth on key nutrient dynamics such as organic carbon (OC), nitrate-nitrogen (NO₃⁻-N), ammonium-nitrogen (NH₄⁺-N), and total nitrogen (TN). The findings reveal that covered pit systems, particularly at greater depths (100 cm), consistently preserve higher concentrations of essential nutrients compared to open pits. This suggests that limiting exposure to oxygen, rainfall, and temperature variations enhances the biochemical stability and fertilizing value of manure.\u003c/p\u003e\u003cp\u003eThe findings also underscore the role of organic and ash-based inputs in enhancing soil fertility by supplying base cations, neutralizing acidity, and enriching the soil solution with soluble salts. However, the magnitude of these changes varied with amendment type, highlighting the importance of balancing input quality and quantity to achieve soil improvement without adverse salinity build-up. This aligns with previous studies that emphasize the dual role of manures and ash as both pH-buffering and conductivity-enhancing agents, with implications for sustainable soil management in acidic and nutrient-depleted soils\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors acknowledge the management of Samburu County Government for providing financial resources for the experimental fields and the technicians for managing the site and aiding in data collection.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research was supported by the Samburu County Government through a postgraduate sponsorship for Master's studies. The authors gratefully acknowledge their financial and institutional support, which made this work possible.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors’ Contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePatrick Lpimari Lesharana: Data analysis, literature review and writing, Erick Oduor Otieno, Mwende Ngie: Supervision, Review and editing, Joseph P. Gweyi: Supervision, Review and Editing, Data analysis, review and editing.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical Approval\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis is not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to Participate\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis is not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to Publish\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis is not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting Interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Availability Statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData will be made available upon request. \u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eBorase DN, Nath CP, Hazra KK, Senthilkumar M, Singh SS, Praharaj CS, Singh U, Kumar N (2020) Long-term impact of diversified crop rotations and nutrient management practices on soil microbial functions and soil enzymes activity. Ecol Ind 114:106322. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/https://doi.org/10.1016/j.ecolind.2020.106322\u003c/span\u003e\u003cspan address=\"10.1016/j.ecolind.2020.106322\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDas S, Liptzin D, Maharjan B (2023) Long-term manure application improves soil health and stabilizes carbon in continuous maize production system. Geoderma 430:116338. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/https://doi.org/10.1016/j.geoderma.2023.116338\u003c/span\u003e\u003cspan address=\"10.1016/j.geoderma.2023.116338\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDuan Y, Yang J, Awasthi MK, Pandey A, Li H (2023) Innovations in design and operation of aeration devices for composting and vermicomposting. In A. Pandey, M. Awasthi, \u0026amp; Z. B. T.-C. D. in B. and B. Zhang (Eds.), \u003cem\u003eCurrent Developments in Biotechnology and Bioengineering\u003c/em\u003e (pp. 57\u0026ndash;81). Elsevier. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/https://doi.org/10.1016/B978-0-323-91874-9.00006-1\u003c/span\u003e\u003cspan address=\"10.1016/B978-0-323-91874-9.00006-1\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eEckardt M, Seidel A-K, S\u0026auml;ger S, Simat TJ (2025) An alternative approach for compliance testing of food and skin contact silicone elastomers by specific determination of volatile cyclic siloxane oligomers via GC-FID. Talanta 283:127145. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/https://doi.org/10.1016/j.talanta.2024.127145\u003c/span\u003e\u003cspan address=\"10.1016/j.talanta.2024.127145\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eFang X, Harris SJ, Leitner SM, Butterbach-Bahl K, Conz RF, Merbold L, Dannenmann M, Oyugi A, Liu S, Zou J, Six J, Barthel M (2024) Mechanisms behind high N2O emissions from livestock enclosures in Kenya revealed by dual-isotope and functional gene analyses. Soil Biol Biochem 196(June):109505. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.soilbio.2024.109505\u003c/span\u003e\u003cspan address=\"10.1016/j.soilbio.2024.109505\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eFAO (2019) \u003cem\u003eWorld Food and Agriculture Statistical Pocketbook\u003c/em\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eFulton-Smith S, Even R, Cotrufo MF (2024) Depth impacts on the aggregate-mediated mechanisms of root carbon stabilization in soil: Trade-off between MAOM and POM pathways. Geoderma 452:117078. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.geoderma.2024.117078\u003c/span\u003e\u003cspan address=\"10.1016/j.geoderma.2024.117078\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eGomez-Munoz B, Larsen JD, Bekiaris G, Scheutz C, Bruun S, Nielsen S, Jensen LS (2017) Nitrogen mineralisation and greenhouse gas emission from the soil application of sludge from reed bed mineralisation systems. J Environ Manage 203:59\u0026ndash;67. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.jenvman.2017.07.042\u003c/span\u003e\u003cspan address=\"10.1016/j.jenvman.2017.07.042\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eGorooei A, Aynehband A, Rahnama A, Gaiser T, Kamali B (2023) Cropping systems and agricultural management strategies affect soil organic carbon dynamics in semi-arid regions. Front Sustainable Food Syst 6:200029. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.3389/fsufs.2022.1016000\u003c/span\u003e\u003cspan address=\"10.3389/fsufs.2022.1016000\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eGuo L, Wu G, Li Y, Li C, Liu W, Meng J, Liu H, Yu X, Jiang G (2016) Effects of cattle manure compost combined with chemical fertilizer on topsoil organic matter, bulk density and earthworm activity in a wheat\u0026ndash;maize rotation system in Eastern China. Soil Tillage Res 156:140\u0026ndash;147. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/https://doi.org/10.1016/j.still.2015.10.010\u003c/span\u003e\u003cspan address=\"10.1016/j.still.2015.10.010\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHuang J, Duan Y, hua, Xu M, gang, Zhai L, mei, Zhai X, bo, Wang Bren, Zhang Y, zhu, Gao S, duan, Sun N (2017) Nitrogen mobility, ammonia volatilization, and estimated leaching loss from long-term manure incorporation in red soil. J Integr Agric 16:2082\u0026ndash;2092. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/S2095-3119(16)61498-3\u003c/span\u003e\u003cspan address=\"10.1016/S2095-3119(16)61498-3\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eIslam SMM, Gaihre YK, Islam MN, Jahan A, Sarkar MAR, Singh U, Islam A, Al Mahmud A, Akter M, Islam MR (2024) Effects of integrated nutrient management and urea deep placement on rice yield, nitrogen use efficiency, farm profits and greenhouse gas emissions in saline soils of Bangladesh. Sci Total Environ 909:168660. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.scitotenv.2023.168660\u003c/span\u003e\u003cspan address=\"10.1016/j.scitotenv.2023.168660\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eJaetzold R, Schmidt H, Hornetz B, Shisanya C (2007) \u003cem\u003eFarm management Handbook of Kenya. Natural conditions and farm management information. Part C- East Kenya. Subpart C1 - Eastern Province: Vol. II\u003c/em\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKoivula N, R\u0026auml;ikk\u0026ouml;nen T, Urpilainen S, Ranta J, H\u0026auml;nninen K (2004) Ash in composting of source-separated catering waste. Bioresour Technol 93:291\u0026ndash;299. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/https://doi.org/10.1016/j.biortech.2003.10.025\u003c/span\u003e\u003cspan address=\"10.1016/j.biortech.2003.10.025\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLi M-X, He X-S, Tang J, Li X, Zhao R, Tao Y-Q, Wang C, Qiu Z-P (2021) Influence of moisture content on chicken manure stabilization during microbial agent-enhanced composting. Chemosphere 264:128549. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/https://doi.org/10.1016/j.chemosphere.2020.128549\u003c/span\u003e\u003cspan address=\"10.1016/j.chemosphere.2020.128549\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLiu Q, Jing W, Yang W, Huang M, Lu P, Hu D (2024) Green manure (Raphanus stativus L.) alters soil microbial structure and promotes acetochlor degradation. Arab J Chem 17:106017. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.arabjc.2024.106017\u003c/span\u003e\u003cspan address=\"10.1016/j.arabjc.2024.106017\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLiu S, Pu S, Deng D, Huang H, Yan C, Ma H, Razavi BS (2020) Comparable effects of manure and its biochar on reducing soil Cr bioavailability and narrowing the rhizosphere extent of enzyme activities. Environ Int 134:105277. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/https://doi.org/10.1016/j.envint.2019.105277\u003c/span\u003e\u003cspan address=\"10.1016/j.envint.2019.105277\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMcCullough CD (2024) The Importance of Nitrate Dynamics in Mine Pit Lakes of Drier Regions. Mine Water Environ 43:231\u0026ndash;254. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s10230-024-00987-1\u003c/span\u003e\u003cspan address=\"10.1007/s10230-024-00987-1\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMiner GL, Delgado JA, Ippolito JA, Stewart CE, Manter DK, Grosso SJ, Del, Floyd BA (2020) Assessing manure and inorganic nitrogen fertilization impacts on soil health, crop productivity, and crop quality in a continuous maize agroecosystem. J Soil Water Conserv 75:1\u0026ndash;18. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.2489/jswc.2020.00148\u003c/span\u003e\u003cspan address=\"10.2489/jswc.2020.00148\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMubarak A, Gali EA, ., Mohamed A, ., Steffens D, Awadelkarim A (2010) Nitrogen Mineralization from Five Manures as Influenced by Chemical Composition and Soil Type. Commun Soil Sci Plant Anal 41:37\u0026ndash;41. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1080/00103624.2010.495802\u003c/span\u003e\u003cspan address=\"10.1080/00103624.2010.495802\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eOtieno EO, Lenga FK, Mburu DM, Kiboi MN, Fliessbach A, Ngetich FK (2024) Combined inorganic and organic fertilizers improved soil microbial biomass and nitrogen dynamics in Upper Eastern region of Kenya. Geoderma Reg 39:e00869. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.geodrs.2024.e00869\u003c/span\u003e\u003cspan address=\"10.1016/j.geodrs.2024.e00869\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eOtieno EO, Mburu DM, Ngetich FK, Kiboi MN, Fliessbach A, Lenga FK (2023) Effects of different soil management strategies on fertility and crop productivity in acidic nitisols of Central Highlands of Kenya. Environ Challenges 11:100683. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.envc.2023.100683\u003c/span\u003e\u003cspan address=\"10.1016/j.envc.2023.100683\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePereira \u0026Aacute;, Lemus J, Navarro P, Palomar J (2025) One-pot integrated CO2 and NH3 capture and utilization using ionic liquids towards ammonium carbamate. Chem Eng J 521:166708. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.cej.2025.166708\u003c/span\u003e\u003cspan address=\"10.1016/j.cej.2025.166708\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRamaswamy J, Prasher SO, Patel RM, Hussain SA, Barrington SF (2010) The effect of composting on the degradation of a veterinary pharmaceutical. Bioresour Technol 101:2294\u0026ndash;2299. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/https://doi.org/10.1016/j.biortech.2009.10.089\u003c/span\u003e\u003cspan address=\"10.1016/j.biortech.2009.10.089\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRayne N, Aula L (2020) Livestock manure and the impacts on soil health: A review. Soil Syst 4:1\u0026ndash;26. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.3390/soilsystems4040064\u003c/span\u003e\u003cspan address=\"10.3390/soilsystems4040064\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eShah A, Huang J, Han T, Khan MN, Tadesse KA, Daba NA, Khan S, Ullah S, Sardar MF, Fahad S, Zhang H (2024) Impact of soil moisture regimes on greenhouse gas emissions, soil microbial biomass, and enzymatic activity in long-term fertilized paddy soil. Environ Sci Europe 36:120. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1186/s12302-024-00943-4\u003c/span\u003e\u003cspan address=\"10.1186/s12302-024-00943-4\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eUNICEF Report (2018) \u003cem\u003eUNICEF Kenya Humanitarian Situation Report, 20 February 2017\u003c/em\u003e. \u003cem\u003eDecember\u003c/em\u003e, 1\u0026ndash;9. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.unicef.org/appeals/files/UNICEF_Kenya_Humanitarian_SitRep_20_Feb_2017.pdf\u003c/span\u003e\u003cspan address=\"https://www.unicef.org/appeals/files/UNICEF_Kenya_Humanitarian_SitRep_20_Feb_2017.pdf\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eWang L, Wen X, Deng Y, Wei Z, Li J, Song C (2025) The microhabitat regulation of moisture - ventilation mediated microbial carbon metabolism in response to humic acid formation during chicken manure and food waste composting. J Environ Manage 389:126048. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/https://doi.org/10.1016/j.jenvman.2025.126048\u003c/span\u003e\u003cspan address=\"10.1016/j.jenvman.2025.126048\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eZhao S, Schmidt S, Qin W, Li J, Li G, Zhang W (2020) Towards the circular nitrogen economy \u0026ndash; A global meta-analysis of composting technologies reveals much potential for mitigating nitrogen losses. Sci Total Environ 704:135401. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/https://doi.org/10.1016/j.scitotenv.2019.135401\u003c/span\u003e\u003cspan address=\"10.1016/j.scitotenv.2019.135401\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eZhou L, Wang Z, Li P, Sa R, Wang Z, Wang N, Xie Y, Yang X (2025) Microbial inoculation influences bacterial and autotrophic community assembly in cow dung\u0026ndash;cotton straw composting to promote carbon sequestration and humification. Environ Technol Innov 39:104290. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.eti.2025.104290\u003c/span\u003e\u003cspan address=\"10.1016/j.eti.2025.104290\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eZhou X, Manna B, Lyu B, Singhal N (2025) Linking oxygen-induced oxidative stress to resource recovery by enhancing the production of extracellular polymeric substances in activated sludge microbial communities. Water Res 286:124238. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.watres.2025.124238\u003c/span\u003e\u003cspan address=\"10.1016/j.watres.2025.124238\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. Contents\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eZhu J, Xia S, Niu H, Xu J, Wang Y, Yu X, Huang L, Zhang K, Wang Y, Zeng L, Li Q, Li L (2025) Volatile organic compounds from typical industries in North China Plain: emissions, air pollution contribution, health risks, and policy implications. Environ Int 202:109673. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/https://doi.org/10.1016/j.envint.2025.109673\u003c/span\u003e\u003cspan address=\"10.1016/j.envint.2025.109673\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eZornoza R, Moreno-Barriga F, Acosta JA, Mu\u0026ntilde;oz MA, Faz A (2016) Stability, nutrient availability and hydrophobicity of biochars derived from manure, crop residues, and municipal solid waste for their use as soil amendments. Chemosphere 144:122\u0026ndash;130. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/https://doi.org/10.1016/j.chemosphere.2015.08.046\u003c/span\u003e\u003cspan address=\"10.1016/j.chemosphere.2015.08.046\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eZougmor\u0026eacute; R, Partey S, Ou\u0026eacute;draogo M, Omitoyin B, Thomas T, Ayantunde A, Ericksen P, Said M, Jalloh A (2016) Toward climate \u0026ndash; smart agriculture in West Africa: a review of climate change impacts, adaptation strategies and policy developments for the livestock, fishery and crop production sectors. Agric Food Secur 1\u0026ndash;16. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1186/s40066-016-0075-3\u003c/span\u003e\u003cspan address=\"10.1186/s40066-016-0075-3\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"County Government of Samburu","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Manure management, mineral nitrogen. nutrient retention, smallholder farming, nitrogen conservation","lastPublishedDoi":"10.21203/rs.3.rs-7545517/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7545517/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe study assessed the effects of different composting strategies on compost quality and chemical characteristics of ASAL soils. A field trial was laid in a randomized complete block design with: control, cattle manure from open compost pit, goat manure + ash from compost pit, cattle manure from covered compost pit, goat manure from open compost pit, goat manure from covered pit, and cattle manure + ash from compost pit. Covered pits at 50 cm depth recorded the highest Nitrate- N levels (188.0 ppm), followed by open pits at 100 cm (148.0 ppm). Goat manure stored in covered pits had significantly lower subsoil nitrate (0.13 ± 0.14) compared with cattle manure in open or covered pits (T2 and T4; 0.47 ± 0.15 and 0.47 ± 0.03, respectively). Soil moisture content improved significantly from 17.08% in T1 to 23.05% in covered pits. The lowest soil bulk density was recorded under plots receiving compost from the covered pits (1.02 g/cm³). Moreover, nitrate-N at a depth of 10–20 cm (p = 0.01) showed a significant treatment effect. Compost from covered pits could be a sustainable approach to enhancing soil fertility and improving agricultural productivity in ASAL soils.\u003c/p\u003e","manuscriptTitle":"Optimizing Cattle and Goat Manure Quality in Semi-arid Agrozone to Improve Fertility Status of Fragile Soils of Samburu County, Kenya","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-09-09 08:53:12","doi":"10.21203/rs.3.rs-7545517/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"13d3d046-f751-4eca-af37-1093a233cd80","owner":[],"postedDate":"September 9th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-10-03T00:43:45+00:00","versionOfRecord":[],"versionCreatedAt":"2025-09-09 08:53:12","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7545517","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7545517","identity":"rs-7545517","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}