Embedded biomass into topsoil as a green production mode to ensure soil structure and functions in arid irrigation region

Embedded biomass into topsoil as a green production mode to ensure soil structure and functions in arid irrigation region | 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 Embedded biomass into topsoil as a green production mode to ensure soil structure and functions in arid irrigation region Ze-Ying Zhao, Peng-Yang Wang, Xiao-Bin Xiong, Jia-Cheng Guo, Hong-Yan Tao, and 7 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7471631/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 Background and Aims Polyethylene film mulching is common in dryland agriculture but may degrade soil functions and environmental quality over time. This study aimed to assess biomass‑based mulching as a sustainable alternative that maintains crop yield while reducing plastic pollution in arid regions. Methods This two‑year field experiment in an arid irrigated region examined soil physicochemical properties, soil enzyme activities, and maize yield under six mulching treatments: shallow‑incorporated dried maize straw (SM), living clover embedding (CM), biomass beneath plastic film (PM + SM and PM + CM), sole plastic film (PM), and bare land control (CK). Results Compared with CK and PM, SM and PM + SM greatly reduced soil bulk density and pH, and increased macroaggregates proportion and geometric mean diameter. Both treatments also enhanced organic carbon and labile carbon contents by 17.7%-21.1% and 27.7%-31.8% compared with PM. CM and PM + CM were most effective in promoting nitrogen cycling, increasing total, organic, and inorganic nitrogen by 4.19%, 18.18%, and 4.65%, respectively, relative to CK. PM + SM and PM + CM also resulted in higher microbial biomass and urease and β-glucosidase activities than PM alone. Structural equation modeling further confirmed that the embedded biomass mulching enhanced soil functions and crop yields. Conclusions While combining biomass with plastic film can maximize agronomic outcomes, sole biomass mulching offers comparable improvements in soil quality and yield without the environmental risks of plastic film. Biomass embedding thus represents a nature‑based, sustainable strategy to advance agricultural productivity and soil health in arid regions. Arid irrigation region Embedded biomass mulching Polythene film mulching Soil structure Soil physicochemical properties Water productivity Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Introduction Polyethylene mulching has broadly adopted as an efficient management practice to enhance crop yield by retaining soil moisture, suppressing weed, regulating soil temperature, and improving nutrient availability in arid and semi-arid agricultural regions (Ma et al., 2018 ; Liu et al., 2023 ). However, the mechanisms underlying its productivity-enhancing effects have been linked to the depletion of soil organic carbon, posing potential threats to soil quality (Lee, 2019; Liu et al., 2023 ). Moreover, the extensive use of plastic mulching has raised growing concerns regarding plastic waste accumulation and soil pollution (Khalid et al., 2023 ; Zhao et al., 2022 ). Therefore, it is crucial to investigate sustainable alternatives to polyethylene mulching that can maintain soil quality and crop productivity while minimizing ecological risks (Scopetani et al., 2025). Nature-based mulching strategies, particularly those utilizing crop residues and living cover crops, present promising alternatives (Zhao et al., 2019; Zhang et al., 2009 ). Crop residues, as a vital source of carbon and nutrients, have been shown to effectively maintain and accumulate soil organic carbon (Wang et al., 2018 ; Zhao et al., 2020 ). Compared to plastic mulching, crop residue mulching has been shown to enhance soil carbon and nitrogen composition in dryland winter wheat systems, while preserving soil microbial diversity (Hao et al., 2025; Fu et al., 2019 ). Similarly, living mulches, typically cover crops grown concurrently with the main crop (e.g., white clover and purple vetch), offers a range of ecological and agronomic benefits (Cougnon et al., 2022 ; Hudson et al., 2023 ). These systems prevent land degradation, reduce nutrient leaching, enhance soil structure, increase microbial biomass, and contribute organic matter (Alletto et al., 2022 ; Hudson et al., 2023 ). Leguminous cover crops, like clover, are particularly valuable for their biological nitrogen fixation capacity, which can significantly reduce the reliance on synthetic nitrogen fertilizers (Sui et al., 2025 ; Alexander et al., 2023 ). Additionally, living mulching enhances soil stability by increasing water infiltration, microbial biomass, and organic matter content, ultimately contributing to higher crop yields (Djigal et al., 2012 ). Specific living mulches like white clover and perennial ryegrass have been shown to directly improve soil aggregate stability (Qi et al., 2022; Holtham et al., 2007 ; Elgersma et al., 1997). Furthermore, white clover is known to increase soil organic carbon and total nitrogen, improve soil enzyme activities (e.g., sucrase, urease, alkaline phosphatase), and enhance bacterial carbon metabolism and microbial community diversity (Wang et al., 2020 ; Lu et al., 2025 ). Despite the established benefits of crop residue and living mulching in various systems, their comprehensive potential as direct substitutes for polyethylene film, particularly in arid irrigated regions heavily reliant on plastic, remains understudied. Understanding how embedded biomass, like shallow straw and living clover, impacts soil properties and yield compared to conventional plastic is vital for sustainable practices in these sensitive areas. Addressing this critical gap, this study aimed to comprehensively evaluate the potential of embedded biomass mulching (including shallow-incorporated straw mulching and living clover mulching) as a substitute for polyethylene film from the perspective of soil quality. The research objectives were: (1) Investigate the impact of different embedded biomass mulching treatments on soil structure and aggregate stability.(2) Assess the effects of embedded biomass mulching on soil nutrient dynamics and organic carbon fractions.(3) Elucidate the responses of soil microbial biomass and key enzyme activities to embedded biomass mulching.(4) Determine the regulatory mechanisms by which embedded biomass mulching influences soil quality parameters and ultimately affects crop yield formation. Materials and methods Site description and experiment design A two-year field experiment (2019 and 2020) was conducted in Jinchang City, located in the central region of the Hexi Corridor in Gansu Province, northwestern China. The experimental site was positioned at coordinates 38°15′-39°00′N and 102°15′-102°43′E, at an altitude of approximately 1430 meters above sea level. The daily maximum and minimum air temperatures, as well as precipitation dynamics during the 2019 and 2020 growing seasons, are presented in Fig. S1 . The background values of the soil are also shown in Fig. S1 . The experiment consisted of six treatments: (1) CK, no mulching; (2) SM, maize straw embedding mulching (12 t ha − 1 ); (3) CM, living clover embedding mulching (120 kg ha − 1 ); (4) PM, pure plastic film mulching; (5) PM + SM, plastic film mulching combined with maize straw embedding; and (6) PM + CM, plastic film mulching combined with living clover embedding. The experiment utilized a randomized complete block design. Each experimental plot measured 25 m² (5 m by 5 m). The plots were established in a ridge-and-furrow configuration, featuring alternating wide ridges (10 cm in height and 70 cm in width) and narrow ridges (15 cm in height and 40 cm in width). For the SM treatment, maize straw pieces were mulched on the ridges and subsequently covered with soil. In the CM treatment, white clover (Trifolium repens L.) seeds were directly sown onto the ridges. For the PM treatment, the ridges were mulched with a transparent polyethylene film of 0.01 mm thickness. In the PM + SM and PM + CM treatments, this transparent film was combined with either maize straw incorporation or the establishment of living clover, respectively. The maize variety “Xianyu1225” was planted on April 26, 2019, and April 24, 2020, with harvest dates on September 28, 2019, and October 7, 2020, respectively. During both growing seasons, all plots received the same basal fertilization: 205 kg ha − 1 of nitrogen (N), 248 kg ha − 1 of phosphorus (P₂O₅), and 60 kg ha − 1 of potassium (K₂O). To align with local irrigation practices, a total irrigation amount of 540 mm was applied across six growth stages during each growing season. Plants were managed using conventional pest, disease, and weed control methods. Crop yield At physiological maturity, four complete and representative maize rows were chosen from each plot for yield parameter measurements. Soil parameters determination In both years, after maize harvesting, soil samples were collected from each plot 0–20 cm and 20–40 cm depths. A portion of the collected soil samples was naturally air-dried and passed through a 0.15 mm sieve for the determination of soil organic carbon (SOC) and total nitrogen (TN). For the analysis of soil pH, easily oxidizable organic carbon (EOC), and particulate organic carbon (POC), samples were sieved through a 2 mm mesh. Another subset of soil samples was promptly transported to the laboratory and stored at -20 ℃ for subsequent analyses, including soil ammonium nitrogen (NH 4 + -N), nitrate nitrogen (NO 3 − -N), microbial biomass carbon (MBC) and nitrogen (MBN), dissolved organic carbon (DOC), dissolved organic nitrogen (DON), dissolved organic matter (DOM), urease activity (URE), and β-glucosidase activity (BG). The undisturbed soil samples were harvested to determine soil bulk density and water-stable aggregates. More details about soil properties determination are given in supplementary files (Section S1). Statical analysis All statistical analyses were conducted using SPSS 22.0 (SPSS Inc., Chicago, USA). Analysis of variance (ANOVA) was employed to evaluate significant differences among treatments. Graphs and figures were generated with Origin 2021. To explore the relationships between soil physicochemical characteristics and crop yield, structural equation modeling (SEM) was applied. Results Changes in the soil pH and bulk density under different mulching treatments Different mulching treatments had significant effects on soil pH in the 0–20 cm and 20–40 cm depths (Fig. 1 a-d). In comparison to PM and CK, SM and CM reduced soil pH in the 0–20 cm depth in 2019 ( p 0.05). In the 20–40 cm soil layer, SM significantly decreased soil pH compared to PM. No significant difference between the dual-mulching treatment and PM was noticed. Straw mulching significantly affects soil bulk density in the 0–20 cm and 20–40 cm soil layers (Fig. 1 e-h). In both growing seasons, under the SM treatment, the bulk density in the 0–20 cm soil layer was 1.36 g cm − 3 and 1.41 g cm − 3 , respectively. Compared to CK, the SM treatment significantly reduced the bulk density in the 0–20 cm soil layer by 12.2%-14.6%, and in 2020, it also significantly reduced the bulk density in the 20–40 cm soil layer by 9.8%. No significant differences were observed among the other mulching treatments. Changes in the soil aggregates composition in different mulching treatments Different mulching treatments significantly influenced the proportion of soil aggregates (Fig. 2 ). In the 0–20 cm soil layer, compared to the CK treatment, all mulching treatments increased the proportion of large aggregates (> 2 mm). Compared to the PM treatment, the SM treatment had a 45.2% increase in the proportion of macroaggregates (> 2 mm), while PM + CM and PM + SM increased by 29.6% and 20.0%, respectively (Fig. 2 a). In the 20–40 cm soil layer, PM + SM exhibited a significant increase in the proportion of macroaggregates, followed by PM, PM + CM, and PM compared with CK. However, CM showed a decrease of 17.4% in the proportion of macroaggregates. Compared to the PM treatment, PM + SM had an 11% increase in the proportion of macroaggregates, while CM, SM, and PM + CM showed reductions of 59.3%, 45.7%, and 17.3%, respectively (Fig. 2 c). The changes in the geometric mean diameter index (GMD) for the 0–20 cm and 20–40 cm soil layers followed a similar trend to the composition of macroaggregates (Fig. 2 b, d). Change in the soil organic carbon and total nitrogen Soil organic carbon (SOC) and total nitrogen (TN) was decreased with the increase of soil depth (Table. 1). The SM and PM + SM treatment significantly increased SOC 16.0% and 20.0% in the 0–20 cm soil layer compared to CK and with 16.9% and 20.9% increase compared to PM, respectively. The clover-involved treatment did not show significant differences in SOC compared with CK and PM. In the 20–40 cm soil layer, PM + SM treatment enhanced SOC by 7.5% in compared to CK. In the 0–20 cm soil layer, PM + SM soil total nitrogen content was increased by 4.7% and 5.3% compared with CK and PM. The CM had a 4.4% increase in TN compared to PM. The different mulching treatments did not significantly impact on TN in the 0–40 cm soil layer. Changes in SOC and TN altered C/N ratio. In the 0–20 cm soil layer, SM and PM + SM resulted in a 12.8% and 15.2% higher C/N ratio, compared with CK ( p < 0.05). Additionally, PM + SM also increased the C/N ratio in the 20–40 cm soil layer by approximately 6.7% ( p < 0.05) (Table. 1). Changes in the soil labile organic carbon and nitrogen fractions Both SM and CM substantially increased the dissolved organic carbon (DOC) content in the 0–20 cm and 20–40 cm soil layers (Fig. 3 ). However, significant differences were noticed in the second growing season compared with CK. Compared with PM, PM + SM significantly increased the DOC content by 11.8% and 13.0% in the 0–20 cm and 20–40 cm soil layers respectively, while PM + CM did not show significant differences compared to PM. Overall, PM + SM had the highest DOC content (71.1 mg kg − 1 ), followed by SM (66.5 mg kg − 1 ) and CM (64.9 mg kg − 1 ). In the 0–20 cm soil layer, SM and PM + SM had higher particulate organic carbon (POC) content than CK and PM, while no significant differences were observed between SM, PM + SM, and CM. In the 20–40 cm soil layer, there were no significant differences in POC content among the treatments (Fig. 3 e-h). Compared to CK and PM, SM significantly increased the easily oxidizable organic carbon (EOC) content in the 0–20 cm and 20–40 cm soil layers (Fig. 3 i-l). The UV/Visible absorption spectra of dissolved organic matter (DOM) were influenced by the mulching treatments (Table 1 ). In the 0–20 cm soil layer, PM + CM exhibited the highest content of SUV254, SUV280, and SUV365, followed by CM, while PM + SM had the lowest content. In the 20–40 cm soil layer, PM and PM + SM had the lowest content of SUV254, SUV280, and SUV365, with no significant difference between them. Table 1 Variations of soil organic carbon (SOC), total nitrogen (TN), C/N and spectral characteristics of soluble organic matter (SUVA254, SUVA280 and SUVA365) in the 0–20 cm and 20–40 cm soil layers under different treatments. Soil depth Treatments SOC (g kg − 1 ) TN (g kg − 1 ) C/N SUVA254 SUVA280 SUVA365 0–20 cm CK 6.31 ± 0.23 b 0.344 ± 0.002 bc 18.28 ± 0.56 b 3.20 ± 0.15 c 2.46 ± 0.08 b 0.88 ± 0.04 bc SM 7.32 ± 0.35 a 0.355 ± 0.003 ab 20.62 ± 0.84 a 3.24 ± 0.06 c 2.50 ± 0.03 b 0.84 ± 0.02 c CM 6.55 ± 0.20 b 0.357 ± 0.004 ab 18.37 ± 0.77 b 3.54 ± 0.09 b 2.72 ± 0.05 a 0.95 ± 0.03 b PM 6.26 ± 0.14 b 0.342 ± 0.005 bc 18.28 ± 0.17 b 2.69 ± 0.12 d 2.10 ± 0.08 c 0.81 ± 0.01 c PM + SM 7.57 ± 0.17 a 0.360 ± 0.003 a 21.06 ± 0.63 a 2.40 ± 0.07 e 1.87 ± 0.05 d 0.70 ± 0.01 d PM + CM 6.25 ± 0.17 b 0.347 ± 0.004 bc 18.02 ± 0.69 b 4.23 ± 0.03 a 3.32 ± 0.05 a 1.17 ± 0.02 a 20–40 cm CK 5.63 ± 0.16 b 0.279 ± 0.002 a 20.19 ± 0.50 b 4.49 ± 0.12 b 3.46 ± 0.10 b 1.25 ± 0.03 b SM 6.01 ± 0.14 ab 0.284 ± 0.004 a 21.18 ± 0.22 ab 3.40 ± 0.25 c 2.61 ± 0.21 c 0.98 ± 0.09 c CM 5.78 ± 0.08 ab 0.283 ± 0.004 a 20.42 ± 0.45 ab 4.41 ± 0.19 b 3.43 ± 0.15 b 1.31 ± 0.05 b PM 5.68 ± 0.15 ab 0.276 ± 0.003 a 20.57 ± 0.43 ab 2.77 ± 0.00 d 2.13 ± 0.00 c 0.78 ± 0.00 c PM + SM 6.05 ± 0.09 a 0.281 ± 0.006 a 21.54 ± 0.32 a 3.16 ± 0.11 cd 2.40 ± 0.08 c 0.82 ± 0.03 c PM + CM 5.73 ± 0.06 ab 0.278 ± 0.005 a 20.65 ± 0.33 ab 6.04 ± 0.01 a 4.20 ± 0.34 a 1.74 ± 0.15 a Notes: CK, not any mulching; SM, maize straw piece embedding mulching; CM, living clover embedding mulching; PM, pure plastic film mulching; PM + SM, plastic film mulching with maize straw piece embedding; PM + CM, plastic film mulching with living clover embedding. Different lower-case letters indicate the significant differences at p < 0.05. In the 0–20 cm soil layer, CM had the highest dissolved organic nitrogen (DON) content. In 2020, CM had 23.9% and 18.5% higher DON compared with CK and PM, respectively ( p < 0.05). In the 20–40 cm soil layer, PM + SM had a significantly higher DON than other treatments in 2019. In the second growing season, SM, CM, PM + SM, and PM + CM accumulated higher DON compared over CK and PM (Fig. 4 a-d). PM + SM resulted in higher NH 4 + -N content in the 0–20 cm soil layer compared with other counterparts (Fig. 4 e, f). However, the NH 4 + -N content in the 20–40 cm soil layer varied between years. In 2019, no significant differences in NH 4 + -N content were observed among the treatments. In 2020, CM and PM + CM had significantly higher NH 4 + -N levels compared with CK and PM (Fig. 4 g, h). The trends in NO 3 − -N content in the 0–20 cm and 20–40 cm soil layers were consistent throughout the growing season, with higher levels of NO 3 − -N observed in SM and PM + SM. Overall, SM, CM, and PM + SM exhibited higher levels of soluble organic nitrogen and inorganic nitrogen (Fig. 4 i-l). Soil microbial biomass response to different mulching In both years, PM + SM and PM + CM had increased the MBC content by 64.5% and 20.6% compared to PM in the 0–20 cm soil layer ( p > 0.05) (Fig. 5 a, b). In the 20–40 cm soil layer, the MBC content of SM, CM, and CK was slightly higher than PM + SM, PM + CM, and PM. In 2020, the MBC content of SM, PM + SM, and CM was increased by 79.6%, 64.3%, and 56.9%, respectively, compared with PM ( p < 0.05) (Fig. 5 c, d). Additionally, in the 0–20 cm soil layer, PM + SM and PM + CM also had higher MBN than other treatments and CK (Fig. 5 e, f). In the 20–40 cm soil layer, the MBN content showed a similar trend as MBC (Fig. 5 g, h). Soil enzyme activities in response to different mulching The activity of soil urease was decreased with the increase of soil depth. In the 0–20 cm soil layer, no significant difference was observed in 2019, however, CM, PM, and PM + SM showed the highest urease activity in 2020, while PM + CM had the lowest urease activity in both growing seasons (Fig. 6 a, b). In the 20–40 cm soil layer, CM and PM displayed relatively higher urease activity (49.4 µg g − 1 h − 1 and 48.7 µg g − 1 h − 1 ), respectively, while PM + CM exhibits the lowest urease activity, but with no significant difference from SM and CK (Fig. 6 c, d). However, PM + CM generally exhibited the highest β-glucosidase activity in the 0–20 cm soil layer, followed by CM, and CK. The single biomass mulching showed significantly higher β-glucosidase activity compared to CK. Under dual-mulching, β-glucosidase activity was higher than PM, with the order of PM + CM > PM + SM > PM (Fig. 6 e, f). The β-glucosidase activity in the 20–40 cm soil layer followed a similar trend as in the 0–20 cm layer. Furthermore, urease and β-glucosidase activity were decreased with the increased soil depth (Fig. 6 g, h). Relationship between soil factors and maize yield In 2019, maize yield under biomass mulching (SM and CM) was increased by 22.0% and 20.9%, respectively, compared with CK. The plastic-involved mulching (PM, PM + SM and PM + CM) resulted in 17.1%, 15.8%, and 9.7%, higher respectively, compared to CK. In 2020, compared to CK, the grain yield under SM and CM was increased by 11.2% and 13.7%, respectively. Under plastic-involved mulching, yield was averagely increase of 11.2% relative to CK. Similar trends were also observed for water use efficiency (WUE) in both years (Table S1 ). By conducting correlation analysis and principal component analysis, indicators needed for the structural equation model were selected to examine the relationships between soil factors and crop yield (Table S2, S3, S4; Fig. 7 ). The model fitted well with the data from all treatments, meeting the established criteria (χ2 = 0.09, df = 1, p = 0.764, CFI = 1.00, GFI = 1.00, RMSEA < 0.001), indicating a good fit of the model to the data. The TN and MBC were positively correlated with yield (Fig. 7 a), explaining a 31% variation in yield. Furthermore, MBC, enzyme activity, and inorganic nitrogen displayed 5%, 19%, and 48% variation, respectively. In the CK-PM treatment, the model exhibited satisfactory parameter values with χ2 = 0.925, df = 2, p = 0.630, CFI = 1.00, GFI = 0.98, and RMSEA < 0.001. This model accounted for 60% of the variation in crop yield. TN had a negative correlation with soil enzyme activity and yield, with the coefficients of -0.70 ( p < 0.001) and − 0.28 ( p < 0.01), respectively. MBC and mineralized nitrogen (MN) had also negative correlations, while MBC positively influenced soil enzyme activity and yield (Fig. 7 b). In the straw-involved treatment, SM-PM + SM, the model showed acceptable parameter values with χ2 = 2.211, df = 2, p = 0.331, CFI = 1.00, GFI = 0.96, and RMSEA = 0.079. This model explained 37% of the variation in crop yield. TN exhibited a negative correlation with MN and yield, and DOC had a negative correlation with MBC. However, MBC had a significant positive effect on enzyme activity, MN, and crop yield (Fig. 7 c). In contrast to the straw-involved treatment, the CM-PM + CM model exhibited significant positive correlations between TN and yield, as well as between MN and crop yield. Moreover, TN showed negative correlations with MBC and MN, respectively. The established model had the following parameters: χ2 = 0.483, df = 2, p = 0.785, CFI = 1.00, GFI = 0.97, and RMSEA < 0.001. It accounted for 46% of the variation in crop yield (Fig. 7 d). Discussion Effects of mulching on soil bulk density and aggregate distribution Soil bulk density is a key indicator of soil structure quality and mineral content (Håkansson et al., 2000). Straw return can improve soil aggregate structure, increase soil porosity, and benefit the activity and reproduction of aerobic microorganisms by improving soil permeability, thereby making soil looser and reducing soil bulk density (Ram et al., 2013 ). In the present study, straw mulching exhibited similar effects to straw return. During the second year, the residual straw from the previous year underwent decomposition and was gradually incorporated into the soil profile. This process notably reduced the soil bulk density at the 20–40 cm soil layer (Fig. 1 ). These findings suggest that straw mulching not only exerts short-term benefits but also contributes to long-term improvement in soil physical properties through its decomposition and integration into the soil (Wang et al., 2023 ). Soil organic matter (SOM) plays a critical role as the primary adhesive agent in the formation and stabilization of soil aggregates (Oades et al., 1984). It is closely associated with aggregate stability, which influences soil structure and function (Six et al., 2004 ; Whitbread et al., 1995; Artemyeva et al., 2021 ). Straw incorporation has been widely recognized as an effective strategy to enhance SOM levels, thereby increasing the contribution of surface aggregates to soil organic carbon (SOC) accumulation (Huang et al., 2018 ). Consistent with these findings, our study demonstrated that SOC in the 0–20 cm soil layer was significantly higher in SM and PM + SM treatments compared to other treatments (Table 1 ). This enhancement in SOC was accompanied by a notable increase in the proportion of macroaggregates (> 2 mm), which improved soil aggregate stability (Fig. 2 ). In addition to organic matter, active iron oxides, including Feo (amorphous iron oxide) and Fep (free iron oxide), serve as crucial adhesive agents that facilitate aggregate stabilization, particularly following the incorporation of organic matter (Asano et al., 2014; Xue et al., 2020 ). Straw incorporation significantly increased the content of iron oxides in the soil, further contributing to aggregate stability (Xue et al., 2020 ). Moreover, the continuous input of straw via surface burial and associated materials created favorable conditions for microbial activity (Yang et al., 2021 ). Microbial decomposition of straw residues and root exudates released bioproducts such as fungal hyphae and bacterial polysaccharides, which enhanced the aggregation of clay and silt particles by acting as temporary binding agents (Lehmann et al., 2017 ). Our findings further revealed that PM + SM increased soil temperature, which stimulated microbial activity and accelerated straw decomposition (Jin et al., 2018 ). This resulted in greater input of organic matter into the soil, promoting the formation of larger soil aggregates (Ma et al., 2024 ). However, in the 0–20 cm soil layer, SM alone contributed more to macroaggregate formation compared to PM + SM (Fig. 2 ). he observed differences can be explained by the progressive decomposition of residual straw incorporated in the SM treatment during the previous growing season (2019). The ongoing breakdown of these residues contributed to a steady release of organic matter into the soil, thereby promoting the formation and stabilization of soil macroaggregates. Conversely, the PM + SM treatment contained a comparatively lower amount of residual straw from 2019, resulting in reduced organic matter input and subsequently a weaker effect on macroaggregate development. The dynamic and interactive effects of SOM, microbial activity, and external inputs highlight the importance of optimizing residue management practices to improve soil structure and stability (Bhattacharyya et al., 2022 ). Recent studies have emphasized the synergistic role of straw-derived organic amendments and microbial interactions in fostering soil aggregation and enhancing soil functionality (Chen et al., 2024 ; Wu et al., 2019 ). For instance, straw decomposition not only supplies organic matter but also modifies soil microenvironmental conditions, creating niches for microbial communities that contribute to aggregate stabilization through biogenic adhesive compounds (Guo et al., 2024 ). These observations align with the results of our study and reinforce the critical importance of residue incorporation in sustainable soil management. Additionally, fresh organic matter has been widely recognized for its ability to enhance microbial activity and improve soil aggregate stability (Fontaine et al., 2007 ). In this study, the CM treatment increased the proportion of macroaggregates in the 0–20 cm soil layer but resulted in a decrease in the 20–40 cm soil layer (Fig. 2 ). This reduction can be attributed to the activity of clover roots, which influenced soil aggregation dynamics. Specifically, low C/N ratio root residues from clover accelerated the mineralization of soil organic matter, leading to localized carbon depletion and subsequent disruption of macroaggregates (Frøseth et al., 2022 ; Six et al., 2004 ). Despite this reduction, the shift in aggregate size was relatively minor, with aggregates only transitioning from 0.5-1 mm to macroaggregates (> 2 mm) (Fig. 2 ). Importantly, the overall percentage of aggregates larger than 0.25 mm remained stable. As a result, both the aggregate stability index and the geometric mean diameter (GMD) of the CM treatment were higher compared to CK, suggesting that clover improved soil quality through modifications to the aggregate size distribution and composition. Specifically, the proportion of carboxyl groups and the ratio of low aromatic ring compounds in soil organic matter play a crucial role in aggregate formation (Verchot et al., 2011 ). The input of fresh organic matter typically increases the proportion of carboxyl groups while decreasing the proportion of stable aromatic organic matter (Ndzelu et al., 2021 ). However, in this study, PM + CM not only increased the proportion of soil macroaggregates (Fig. 2 ), but also significantly increased the content of high molecular weight aromatic compounds in the soluble organic matter fraction (Table 1 ). This could be attributed to changes in the organic matter composition induced by clover under plastic film. Notably, the hydrophobic nature of aromatic compounds could form a hydrophobic protective layer around soil organic matter, preventing its microbial decomposition and enhancing aggregate stability (Semenov et al., 2013 ). However, this differs from the effect of soluble aromatic compounds observed in this study, which have no hydrophobic properties. For example, a typical component of humic substances, fulvic acid, which contains a benzene ring and a carboxyl group had no negative impact on the aggregation of soil aggregates. Changes in soil chemistry under different mulching The respiratory release of CO 2 by root systems has been shown to influence soil pH (Hinsinger et al., 2003 ). In this study, SM and CM treatments significantly decreased soil pH compared to PM + SM, PM + CM, and PM treatments (Fig. 1 ). This reduction was likely attributed to the higher root biomass and elevated root respiration rates in SM and CM (Table S1 ), which resulted in substantial CO 2 emissions and subsequent soil acidification. Additionally, the secretion of acidic compounds, such as organic acids, by roots further contributed to the observed pH reduction (Zeng et al., 2008 ). During the late growth stages of maize, the PM + SM, PM + CM, and PM treatments facilitated earlier plant maturity, which led to reduced root biomass and lower production of root exudates. This diminished the influence of root processes on soil pH, resulting in minimal changes. Notably, soil pH changes were more pronounced in 2019 compared to 2020, likely due to microbial community shifts induced by the biomass addition in 2019 (Table S1 ). These shifts in microbial composition may have influenced organic matter decomposition rates and nutrient cycling processes, ultimately contributing to a more stable soil pH in 2020. This stabilization is indicative of negative feedback mechanisms and adaptation within the soil system (Pietri et al., 2009; Wang et al., 2024). However, the elevated soil moisture and temperature associated with plastic film mulching can accelerate the mineralization of soil organic matter in irrigated areas, ultimately leading to a decline in soil organic carbon content (Yu et al., 2021 ). In both years of the study, the contribution of PM to soil organic carbon was similar to or lower than that of CK (Table 1 ). In the irrigated regions of the Hexi Corridor, the maize root biomass input under PM practice was insufficient to offset the accelerated mineralization rate of soil organic matter. Prolonged exposure to high soil temperatures and moisture exacerbates the mineralization process, resulting in the depletion of soil organic carbon. These findings indicate that long-term polyethylene mulch cover is not a sustainable soil management practice in these regions (Steinmetz et al., 2016 ). Moreover, the trend of organic carbon changes in the PM + CM was consistent with the PM treatment. Although clover contributed to organic matter input, higher temperature and moisture retention intensify the microbial mineralization of fresh organic matter (Whitman et al., 2016 ). This increased mineralization offset the positive contribution of clover to soil organic carbon, further illustrating the challenges of sustaining soil organic matter levels under mulching practices that exacerbate mineralization conditions. Furthermore, the organic carbon content in the CM treatment was not significantly different from that in the PM + CM treatment but was slightly higher, possibly due to the absence of the PM layer, which may have catalyzed organic matter accumulation and decomposition processes. In addition, dual plastic and maize straw mulching (PM + SM) accelerated the straw decomposition rate. By the second year, the decomposed straw was incorporated into the soil, leading to an increase in soil organic carbon (SOC) content within the 0–40 cm soil layer. Previous studies have demonstrated that decomposed straw serves as an effective soil amendment, contributing to improved soil fertility and carbon sequestration (Liang et al., 2021 ; Liu et al., 2014 ). Notably, the SM treatment resulted in a marked increase in organic carbon content in the 0–20 cm soil layer, likely due to the incorporation of partially decomposed straw, which raised the soil C/N ratio (Zhang et al., 2015 ). The higher C/N ratio in SM limited nitrogen availability for microorganisms, reducing the decomposition and transformation of straw-derived organic matter compared to the PM + SM treatment. While excessive straw mulching can inhibit SOC accumulation by suppressing microbial activity, this typically occurs through mechanisms such as nitrogen immobilization caused by a high C/N ratio and reduced soil aeration limiting oxygen availability for microbial respiration (Mary et al., 1996 ; Guo et al., 2015). Additionally, the accumulation of intermediate decomposition products, such as organic acids, can further suppress microbial activity (Kuzyakov, 2010 ). In this study, however, no such inhibition was observed, suggesting that the applied straw mulching rate was appropriate to sustain microbial activity and promote SOC accumulation. Dissolved organic carbon (DOC) serves as a primary energy source for microorganisms, while microbial metabolites also contribute significantly to DOC pools (Fang et al., 2005). In this study, SM and PM + SM treatments significantly increased DOC content compared to CK and PM, primarily due to straw decomposition, which released substantial amounts of DOC, labile organic carbon, and nitrogen, thereby providing essential nutrients for microbial activity (Wang et al., 2018 ). Notably, PM + SM accelerated straw decomposition more effectively than SM alone, resulting in higher DOC levels. Additionally, both SM and PM + SM increased the contents of easily oxidizable carbon and particulate organic carbon (Fig. 4 ), highlighting straw mulching as an effective soil management practice for improving the fertility of low-nutrient farmland (Liu et al., 2014 ). The enhanced carbon availability under SM and PM + SM stimulated microbial metabolism, promoting the release of additional nutrients and soluble organic compounds. These compounds further supported microbial growth, establishing a positive feedback loop that reinforced carbon turnover and nutrient cycling (Chen et al., 2017 ; Yang et al., 2018 ). In this two-year study, changes in soil total nitrogen content were minimal, with significant differences observed only in the 0–20 cm soil layer, where PM + SM significantly increased TN content. Straw incorporation is known to elevate the soil carbon-to-nitrogen (C/N) ratio due to high carbon inputs (Meng et al., 2024 ). Consistent with this, our study found that both SM and PM + SM treatments significantly elevated the soil C/N ratio. In contrast, PM accelerated soil organic matter mineralization, leading to a reduction in the C/N ratio. Similarly, CM and PM + CM decreased the C/N ratio, likely due to clover’s contribution to soil nitrogen as an effective green manure source. Furthermore, dissolved organic nitrogen (DON) and inorganic nitrogen (e.g., NH4 + -N) serve as active nitrogen sources for microbial processes. In 2019, there were no significant differences in DON andNH4 + -N content between CM and CK in the 0–20 cm soil layer, whereas significant differences appeared in 2020. This suggests that clover inputs organic matter into the soil during the first growing season, contributing to increased DON and NH4 + -N content in the subsequent year. Variations in DON and NH4 + -N content in the 20–40 cm soil layer between years further highlight the interannual cumulative effects of single biomass covers, such as clover, on nitrogen dynamics. Effects of mulching on soil microbial biomass and enzyme dynamics Although microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) constitute a small fraction of soil organic carbon and total nitrogen, they are highly sensitive indicators of soil management practices (Franchini et al., 2007 ). In this study, treatments involving organic inputs (SM, CM, PM + SM, and PM + CM) significantly increased soil MBC and MBN content compared to CK and PM. Biomass cover enhanced soil biochemical properties and stimulated microbial activity (Chen et al., 2017 ). Notably, the cumulative effect of dual plastic and biomass mulching on microbial biomass was superior to that of sole biomass mulching, likely due to the improved water and heat conditions provided by the combined mulching, which fostered microbial activity. Furthermore, sole straw mulching contributed more to MBC, while sole clover mulching was more effective in increasing MBN, reflecting the distinct carbon and nitrogen composition of the respective biomass inputs. In general, plastic film mulching creates favorable hydrothermal conditions that accelerate biomass decomposition, thereby supplying carbon and nitrogen sources essential for soil microorganisms and enhancing soil enzyme activity (Tejada et al., 2014). Consistent with this, our study observed significant increases in urease activity under the PM + SM treatment and β-glucosidase activity under the PM + CM treatment. These differential effects of biomass mulching on soil enzyme activity may be linked to its impact on microbial community composition and structure. Additionally, our findings revealed that sole biomass mulching effectively increases the abundance of dominant phyla within soil bacterial and fungal communities, further influencing soil biochemical processes (Zhao et al., 2022 ). Interactions between soil properties and crop yield under mulching treatments Among all treatments, biomass cover treatments (PM + SM, PM + CM, SM, CM) significantly enhanced soil organic matter (SOM) and total nitrogen (TN) content. Furthermore, the active components of SOM and nitrogen, such as dissolved organic carbon (DOC) and inorganic nitrogen (MN), also showed notable increases. This improvement can be attributed to the input of fresh organic matter from straw or clover and the favorable hydrothermal conditions created by the cover treatments, which stimulated microbial proliferation and soil enzyme activity (Akhtar et al., 2019). As a result, simultaneous increases were observed in DOC, TN, microbial biomass, soil enzyme activity, inorganic nitrogen, and ultimately, crop yield. Structural equation modeling (SEM) conducted for CK-PM, SM-PM + SM, and CM-PM + CM treatments revealed strong positive correlations between microbial biomass carbon (MBC) and soil enzyme activity, as well as between MBC and maize grain yield. This underscores the critical role of microbial biomass in driving soil biochemical processes, contributing to nutrient availability, and supporting crop productivity. In the SEM analysis of CK-PM, a significant negative correlation was observed between total nitrogen (TN) and both soil enzyme activity and grain yield, attributed to lower microbial activity and yield in CK compared to PM. The PM treatment, with higher microbial biomass, enhanced nitrogen mineralization, converting organic nitrogen in TN into plant-available inorganic nitrogen (Zhang et al., 2019 ). As a result, PM showed increased microbial biomass carbon (MBC), enzyme activity, and grain yield, despite lower TN and mineral nitrogen (MN) than CK. However, long-term polyethylene mulching disrupted nitrogen balance, reducing soil fertility and requiring increased nitrogen fertilizer application, which risks nitrogen loss and environmental pollution (Li et al., 2021 ). In the SM-PM + SM group, crop residue decomposition provided continuous nitrogen inputs, promoting microbial nitrogen mineralization (Zhao et al., 2020 ). The PM + SM treatment accelerated residue decomposition, enhancing microbial growth through increased carbon input (Yang et al., 2018 ), resulting in a positive correlation between microbial biomass carbon (MBC) and mineral nitrogen (MN). However, higher microbial biomass in PM + SM led to greater consumption of dissolved organic carbon (DOC), causing a significant negative correlation between DOC and MBC. These findings align with studies showing that elevated microbial activity can deplete DOC faster than its replenishment (Fang et al., 2005). No significant differences were found between PM + SM and SM treatments in grain yield, total nitrogen (TN), and mineral nitrogen (MN) content, indicating that the negative correlation between TN and grain yield, as well as TN and MN, is driven by intra-group variations rather than inter-group differences. Notably, TN was measured using the Kjeldahl method, which excludes nitrate and nitrite fractions (Jansson et al., 1982). The mineralization of TN to MN likely explains the negative correlation observed between TN and MN, consistent with previous findings (Zhang et al., 2019 ). Additionally, MN accounted for up to 95% of the variation in structural equation models, highlighting its strong linkage to microbial biomass dynamics (Li et al., 2021 ). In the CM-PM + CM system, TN was significantly negatively correlated with MN, but the underlying mechanism differed from that in the SM-PM + SM system. The CM treatment, incorporating clover as a leguminous crop, enhanced soil total nitrogen (TN) through biological nitrogen fixation and incorporation via tillage (Parr et al., 2011 ). However, TN was lower in PM + CM compared to CM, likely due to accelerated nitrogen mineralization under the higher moisture and temperature conditions created by plastic film mulching, resulting in increased soil inorganic nitrogen (MN) levels (Yu et al., 2021 ; Tejada et al., 2014). Additionally, in the clover system, TN exhibited a significant positive correlation with grain yield, attributed to the stable nitrogen input from clover roots and improved soil hydrothermal conditions provided by biomass mulching. These findings align with previous studies highlighting the role of leguminous cover crops in enhancing nitrogen availability and improving crop yield (Zhao et al., 2022 ). Conclusions This study showed that both sole biomass mulching (SM, CM) and dual mulching with plastic film (PM + SM, PM + CM) significantly improved soil structure, nutrient status, and maize yield compared to bare land (CK) and conventional plastic film mulching (PM). PM + SM and PM + CM further enhanced macroaggregate formation, soil organic carbon, nitrogen cycling, microbial biomass, and enzyme activities, resulting in the highest yield and water use efficiency. Notably, sole biomass mulching (SM, CM) also delivered substantial improvements in soil quality and crop productivity without the environmental drawbacks of plastic film. These findings suggest that while dual mulching maximizes agronomic performance, sole biomass mulching represents a more sustainable and eco-friendly strategy for arid farmland management. Declarations Competing Interest Statement: Authors declare that they have no competing interests. Author contributions: Z.Y. Zhao and P.Y. Wang: Conceptualization, Methodology, Data collection, Sample analysis, Data analysis, Writing-draft, Visualization. X.B. Xiong, J.C. Guo, W.S. Li, N. Chang, Y.L. Chen, X.L. Zhang, and N. Wang: Data collection, Data analysis. Y. Chen, H.Y. Tao: Supervision, Writing- review & editing, Validation. Y.C. Xiong (Corresponding author): Conceptualization, Investigation, Writing- review & editing, Supervision, Validation. Acknowledgements: This work was supported by National Key R&D Program of China (2024YFC3713900), National Natural Science Foundation of China (32401418), Fundamental Research Funds for the Central Universities (lzujbky-2024-jdzx11, lzujbky-2025-13, -it22), and Science and Technology Project of Gansu Province of China (24JRRA494). References Alexander J R, Baker J M, Gamble J D, Venterea R T, Spokas K A. Spatiotemporal distribution of roots in a Maize-Kura clover living mulch system: Impact of tillage and fertilizer N source. Soil & Tillage Research , 2023, 227: 105590. Alletto L, Cassigneul A, Duchalais A, et al. Cover crops maintain or improve agronomic performances of maize monoculture during the transition period from conventional to no-tillage. Field Crops Research , 2022, 283: 108540. Artemyeva Z, Danchenko N, Kolyagin Y, et al. Chemical structure of soil organic matter and its role in aggregate formation in Haplic Chernozem under the contrasting land use variants. Catena , 2021, 204: 105403. Asano M, Wagai R. Evidence of aggregate hierarchy at micro-to submicron scales in an allophanic Andisol. Geoderma , 2014, 216: 62-74. Bhattacharyya S S, Ros G H, Furtak K, et al. Soil carbon sequestration–An interplay between soil microbial community and soil organic matter dynamics. Science of the Total Environment , 2022, 815: 152928. Chen H, Hao Y, Ma Y, et al. Maize straw-based organic amendments and nitrogen fertilizer effects on soil and aggregate-associated carbon and nitrogen. Geoderma , 2024, 443: 116820. Chen Z, Wang H, Liu X, et al. Changes in soil microbial community and organic carbon fractions under short-term straw return in a rice–wheat cropping system. Soil and Tillage Research , 2017, 165: 121-127. Cougnon M, Durand J L, Julier B, et al. Using perennial plant varieties for use as living mulch for winter cereals. A review. Agronomy for Sustainable Development , 2022, 42: 110. Djigal D, Saj S, Rabary B, et al. Mulch type affects soil biological functioning and crop yield of conservation agriculture systems in a long-term experiment in Madagascar. Soil and Tillage Research , 2012, 118: 11-21. Elgersma A, Hassink J. Effects of white clover ( Trifolium repens L.) on plant and soil nitrogen and soil organic matter in mixtures with perennial ryegrass ( Lolium perenne L.). Plant and Soil , 1997, 197: 177-186. Fang C, Moncrieff J B. The variation of soil microbial respiration with depth in relation to soil carbon composition. Plant and Soil , 2005, 268: 243-253. Fontaine S, Barot S, Barré P, et al. Stability of organic carbon in deep soil layers controlled by fresh carbon supply. Nature , 2007, 450: 277-280. Fontaine S, Mariotti A, Abbadie L. The priming effect of organic matter: a question of microbial competition? Soil Biology and Biochemistry , 2003, 35: 837-843. Franchini J C, Crispino C C, Souza R A, et al. Microbiological parameters as indicators of soil quality under various soil management and crop rotation systems in southern Brazil. Soil and Tillage Research , 2007, 92(1-2): 18-29. Frøseth R B, Thorup-Kristensen K, Hansen S, et al. High N relative to C mineralization of clover leaves at low temperatures in two contrasting soils. Geoderma , 2022, 406: 115483. Fu X, Wang J, Sainju U M, et al. Soil microbial community and carbon and nitrogen fractions responses to mulching under winter wheat. Applied Soil Ecology , 2019, 139: 64-68. Guo W, Zhang Y, Xu J, et al. Straw management and fertilization improve soil aggregate stability by inducing biological binding agents and specific keystone genera. Pedosphere, 2024, 34: 40-51. Håkansson I, Lipiec J. A review of the usefulness of relative bulk density values in studies of soil structure and compaction. Soil and Tillage Research , 2000, 53: 71-85. Hinsinger P, Plassard C, Tang C, et al. Origins of root-mediated pH changes in the rhizosphere and their responses to environmental constraints: a review. Plant and Soil , 2003, 248: 43-59. Holtham D A L, Matthews G P, Scholefield D S. Measurement and simulation of void structure and hydraulic changes caused by root-induced soil structuring under white clover compared to ryegrass. Geoderma , 2007, 142: 142-151. Huang R, Tian D, Liu J, et al. Responses of soil carbon pool and soil aggregates associated organic carbon to straw and straw-derived biochar addition in a dryland cropping mesocosm system. Agriculture, Ecosystems & Environment , 2018, 265: 576-586. Hudson T B, Alford A M, Bilbo T R, et al. Living mulches reduce natural enemies when combined with frequent pesticide applications. Agriculture, Ecosystems & Environment , 2023, 357: 108680. Jansson S L, Persson J. Mineralization and immobilization of soil nitrogen. Nitrogen in Agricultural Soils , 1982, 22: 229-252. Jin X, An T, Gall A R, et al. Enhanced conversion of newly-added maize straw to soil microbial biomass C under plastic film mulching and organic manure management. Geoderma , 2018, 313: 154-162. Khalid N, Aqeel M, Noman A, et al. Impact of plastic mulching as a major source of microplastics in agroecosystems. Journal of Hazardous Materials , 2023, 445: 130455. Kuzyakov Y. Priming effects: interactions between living and dead organic matter. Soil Biology and Biochemistry , 2010, 42: 1363-1371. Lee J G, Hwang H Y, Park M H, et al. Depletion of soil organic carbon stocks are larger under plastic film mulching for maize. European Journal of Soil Science , 2019, 70: 807-818. Lehmann A, Zheng W, Rillig M C. Soil biota contributions to soil aggregation. Nature Ecology & Evolution , 2017, 1: 1828-1835. Li H, Wang L, Peng Y, et al. Film mulching, residue retention and N fertilization affect ammonia volatilization through soil labile N and C pools. Agriculture, Ecosystems & Environment , 2021, 308: 107272. Liang Y, Al-Kaisi M, Yuan J, et al. Effect of chemical fertilizer and straw-derived organic amendments on continuous maize yield, soil carbon sequestration and soil quality in a Chinese Mollisol. Agriculture, Ecosystems & Environment , 2021, 314: 107403. Liu C, Lu M, Cui J, et al. Effects of straw carbon input on carbon dynamics in agricultural soils: a meta‐analysis. Global Change Biology , 2014, 20: 1366-1381. Liu Z, Zhao C, Zhang P, et al. Long-term effects of plastic mulching on soil structure, organic carbon and yield of rainfed maize. Agricultural Water Management , 2023, 287: 108447. Lu J, Tian H, Xiong J, et al. Effects of N and P fertilization on soil N-cycling microbial community structure in white clover grasslands. Current Microbiology , 2025, 82: 1-14. Ma D, Chen L, Qu H, et al. Impacts of plastic film mulching on crop yields, soil water, nitrate, and organic carbon in Northwestern China: A meta-analysis. Agricultural Water Management , 2018, 202: 166-173. Ma S, Cao Y, Lu J, et al. Response of soil aggregation and associated organic carbon to organic amendment and its controls: A global meta-analysis. Catena , 2024, 237: 107774. Mary B, Recous S, Darwis D, et al. Interactions between decomposition of plant residues and nitrogen cycling in soil. Plant and Soil , 1996, 181: 71-82. Meng X, Zhang X, Li Y, et al. Nitrogen fertilizer builds soil organic carbon under straw return mainly via microbial necromass formation. Soil Biology and Biochemistry , 2024, 188: 109223. Ndzelu B S, Dou S, Zhang X, et al. Tillage effects on humus composition and humic acid structural characteristics in soil aggregate-size fractions. Soil and Tillage Research , 2021, 213: 105090. Parr M, Grossman J M, Reberg‐Horton S C, et al. Nitrogen delivery from legume cover crops in no‐till organic corn production. Agronomy Journal , 2011, 103: 1578-1590. Pietri J C A, Brookes P C. Substrate inputs and pH as factors controlling microbial biomass, activity and community structure in an arable soil. Soil Biology and Biochemistry , 2009, 41: 1396-1405. Ram H, Dadhwal V, Vashist K K, et al. Grain yield and water use efficiency of wheat ( Triticum aestivum L.) in relation to irrigation levels and rice straw mulching in North West India. Agricultural Water Management , 2013, 128: 92-101. Semenov V M, Tulina A S, Semenova N A, et al. Humification and nonhumification pathways of the organic matter stabilization in soil: A review. Eurasian Soil Science , 2013, 46: 355-368. Six J, Bossuyt H, Degryze S, et al. A history of research on the link between (micro) aggregates, soil biota, and soil organic matter dynamics. Soil and Tillage Research , 2004, 79: 7-31. Steinmetz Z, Wollmann C, Schaefer M, et al. Plastic mulching in agriculture. Trading short-term agronomic benefits for long-term soil degradation? Science of the Total Environment , 2016, 550: 690-705. Sui X, Bao X, Xie H, et al. Contrasting seasonal effects of legume and grass cover crops as living mulch on the soil microbial community and nutrient metabolic limitations. Agriculture, Ecosystems & Environment , 2025, 380: 109374. Tejada M, Benítez C. Effects of crushed maize straw residues on soil biological properties and soil restoration. Land Degradation & Development , 2014, 25: 501-509. Verchot L V, Dutaur L, Shepherd K D, et al. Organic matter stabilization in soil aggregates: understanding the biogeochemical mechanisms that determine the fate of carbon inputs in soils. Geoderma , 2011, 161: 182-193. Wang J, Fu X, Sainju U M, et al. Soil carbon fractions in response to straw mulching in the Loess Plateau of China. Biology and Fertility of Soils , 2018, 54: 423-436. Wang M, Liu Z, Zhai B, et al. Long-term straw mulch underpins crop yield and improves soil quality more efficiently than plastic mulch in different maize and wheat systems. Field Crops Research , 2023, 300: 109003. Wang Y, Liu L, Tian Y, et al. Temporal and spatial variation of soil microorganisms and nutrient under white clover cover. Soil and Tillage Research , 2020, 202: 104666. Whitman T, Pepe-Ranney C, Enders A, et al. Dynamics of microbial community composition and soil organic carbon mineralization in soil following addition of pyrogenic and fresh organic matter. The ISME Journal , 2016, 10: 2918-2930. Wu L, Zhang W, Wei W, et al. Soil organic matter priming and carbon balance after straw addition is regulated by long-term fertilization. Soil Biology and Biochemistry , 2019, 135: 383-391. Xue B, Huang L, Huang Y, et al. Straw management influences the stabilization of organic carbon by Fe (oxyhydr)oxides in soil aggregates. Geoderma , 2020, 358: 113987. Yang H, Fang C, Meng Y, et al. Long-term ditch-buried straw return increases functionality of soil microbial communities. Catena , 2021, 202: 105316. Yang Y, Yu K, Feng H. Effects of straw mulching and plastic film mulching on improving soil organic carbon and nitrogen fractions, crop yield and water use efficiency in the Loess Plateau, China. Agricultural Water Management , 2018, 201: 133-143. Yu Y, Zhang Y, Xiao M, et al. A meta-analysis of film mulching cultivation effects on soil organic carbon and soil greenhouse gas fluxes. Catena , 2021, 206: 105483. Zeng F, Chen S, Miao Y, et al. Changes of organic acid exudation and rhizosphere pH in rice plants under chromium stress. Environmental Pollution , 2008, 155: 284-289. Zhang P, Wei T, Li Y, et al. Effects of straw incorporation on the stratification of the soil organic C, total N and C:N ratio in a semiarid region of China. Soil and Tillage Research , 2015, 153: 28-35. Zhang S, Lövdahl L, Grip H, et al. Effects of mulching and catch cropping on soil temperature, soil moisture and wheat yield on the Loess Plateau of China. Soil and Tillage Research , 2009, 102: 78-86. Zhang S, Zheng Q, Noll L, et al. Environmental effects on soil microbial nitrogen use efficiency are controlled by allocation of organic nitrogen to microbial growth and regulate gross N mineralization. Soil Biology and Biochemistry , 2019, 135: 304-315. Zhao X, Liu B Y, Liu S L, et al. Sustaining crop production in China's cropland by crop residue retention: A meta‐analysis. Land Degradation & Development , 2020, 31: 694-709. Zhao Z, Wang P, Xiong X, et al. Environmental risk of multi-year polythene film mulching and its green solution in arid irrigation region. Journal of Hazardous Materials , 2022, 435: 128981. Supplementary Files SupplementaryInformationPlantandSoil.docx 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-7471631","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":512158501,"identity":"64d1866c-9a8a-43e5-b1e7-73e9864f2f84","order_by":0,"name":"Ze-Ying Zhao","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Ze-Ying","middleName":"","lastName":"Zhao","suffix":""},{"id":512158502,"identity":"42b76c88-c506-4dc9-8602-881b12b3462a","order_by":1,"name":"Peng-Yang Wang","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Peng-Yang","middleName":"","lastName":"Wang","suffix":""},{"id":512158503,"identity":"36934ea5-5e02-4764-b43f-87d38ece5fc4","order_by":2,"name":"Xiao-Bin Xiong","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Xiao-Bin","middleName":"","lastName":"Xiong","suffix":""},{"id":512158504,"identity":"b99aee8c-0464-4472-a584-8e64f9ea1a3e","order_by":3,"name":"Jia-Cheng Guo","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Jia-Cheng","middleName":"","lastName":"Guo","suffix":""},{"id":512158505,"identity":"b1e96832-a701-4336-9b94-2dff3776946c","order_by":4,"name":"Hong-Yan Tao","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Hong-Yan","middleName":"","lastName":"Tao","suffix":""},{"id":512158506,"identity":"5748dca9-295f-41f1-bb0b-2050806719e5","order_by":5,"name":"Wen-Shan Li","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Wen-Shan","middleName":"","lastName":"Li","suffix":""},{"id":512158507,"identity":"375e3a51-a7af-410b-ad8e-dcaf785208fe","order_by":6,"name":"Yun-Lu Chen","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Yun-Lu","middleName":"","lastName":"Chen","suffix":""},{"id":512158508,"identity":"32579162-64e1-45cf-8ac8-2232b6bd4879","order_by":7,"name":"Nan Chang","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Nan","middleName":"","lastName":"Chang","suffix":""},{"id":512158509,"identity":"ef384484-053c-47ed-ad5a-7271075643bf","order_by":8,"name":"Yinglong Chen","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Yinglong","middleName":"","lastName":"Chen","suffix":""},{"id":512158510,"identity":"abede105-40ea-46be-80d4-40627dd094e3","order_by":9,"name":"Xiao-Lin Zhang","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Xiao-Lin","middleName":"","lastName":"Zhang","suffix":""},{"id":512158511,"identity":"2105715d-2b82-4d4d-ba89-a5be235a4add","order_by":10,"name":"Ning Wang","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Ning","middleName":"","lastName":"Wang","suffix":""},{"id":512158512,"identity":"a8d99315-f1a6-4036-8bc3-b83720ec5815","order_by":11,"name":"You-Cai Xiong","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAzklEQVRIiWNgGAWjYDACZgglxwem2EjQYsxGvBYoSGwjWovBceZjD7+22aW38Z8xYPhQdpiBf3YDfi2SzWzpxrJtybltDGcMGGecO8wgcecAfi38zDxm0pJtB3LbGHsMmHnbDjMYSCTg18IG1ZIOZBgw/yVGC8gWyY9tBxLY2IBaGInRAvRLmjTDuWTDNh62goM959J5JG4Q0GJw/vAxyR9ldvL8/Ic3PvhRZi3HP4OAFhBg5oVGxwEg5iGsHggYf/whSt0oGAWjYBSMVAAA+Mo3KVhfam0AAAAASUVORK5CYII=","orcid":"https://orcid.org/0000-0002-4394-8331","institution":"State Key Laboratory of Grassland Agro-Ecosystems","correspondingAuthor":true,"prefix":"","firstName":"You-Cai","middleName":"","lastName":"Xiong","suffix":""}],"badges":[],"createdAt":"2025-08-27 12:25:25","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7471631/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7471631/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":91411892,"identity":"afed195c-a85f-4ed6-9b26-e8efabd6a26d","added_by":"auto","created_at":"2025-09-16 08:52:10","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":612676,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eVariations of soil bulk density and pH in the 0–20 cm and 20–40 cm soil layers in response to biomass embedding in two growing seasons from 2019 to 2020.\u003c/strong\u003e CK, not any mulching; SM, maize straw piece embedding mulching; CM, living clover embedding mulching; PM, pure plastic film mulching; PM+SM, plastic film mulching with maize straw piece embedding; PM+CM, plastic film mulching with living clover embedding (the same in the below). Different lower-case letters indicate the significant differences at \u003cem\u003ep\u003c/em\u003e\u0026lt;0.05 (the same in the below).\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-7471631/v1/21b91739536bd4f9b697b1ac.png"},{"id":91413208,"identity":"57ad0a05-f36d-47ac-b2d8-0e2948302d1e","added_by":"auto","created_at":"2025-09-16 09:00:10","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":852805,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eVariations of soil water-stable aggregate and geometric mean diameter (GMD) in the 0–20 cm and 20–40 cm soil layers in response to biomass embedding at the end of 2020 growing season.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-7471631/v1/933feb8a3b1e33bef8aa1786.png"},{"id":91411894,"identity":"8b743e11-f13d-4cf2-8cb0-a0562066b411","added_by":"auto","created_at":"2025-09-16 08:52:10","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":1410461,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eVariations of soil dissolved organic carbon, particulate organic carbon, and easily oxidizable carbon content in the 0–20 cm and 20-40 cm soil layers in response to biomass embedding after two growing seasons.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-7471631/v1/cd4de8cf6eab00dd7a6be594.png"},{"id":91415220,"identity":"e2e83542-e830-4c06-af3a-b60d143e9964","added_by":"auto","created_at":"2025-09-16 09:16:10","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":1506656,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eVariations of soil dissolved organic nitrogen, ammonium nitrogen and nitrate nitrogen content in the 0–20 cm and 20-40 cm soil layers in response to biomass embedding in two growing seasons from 2019 to 2020.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-7471631/v1/73402015eec0a5d3c1adfa35.png"},{"id":91413210,"identity":"7287ad8e-cbcd-4090-9ecb-7e896cb8f9b3","added_by":"auto","created_at":"2025-09-16 09:00:10","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":833818,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eVariations of soil microbial biomass carbon and microbial biomass nitrogen content in the 0–20 cm and 20-40 cm soil layers in response to biomass embedding in two growing seasons from 2019 to 2020.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"floatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-7471631/v1/ad89fecc161112eea968a389.png"},{"id":91413756,"identity":"bc25dbf4-f4a4-48fa-a702-4753f4f58014","added_by":"auto","created_at":"2025-09-16 09:08:10","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":151584,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eVariations of soil Urease activity and β-glucosidase activity in the 0–20 cm and 20-40 cm soil layers in response to biomass embedding in two growing seasons from 2019 to 2020.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"floatimage6.png","url":"https://assets-eu.researchsquare.com/files/rs-7471631/v1/4d10f5b1f0dd921fbcaa0dca.png"},{"id":91413211,"identity":"59533edb-2f68-4208-807c-26a2a7009973","added_by":"auto","created_at":"2025-09-16 09:00:10","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":633364,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eStructural equation modeling revealing the direct and indirect relationships between soil physicochemical properties and maize yield. \u003c/strong\u003ea, Total treatment; b, CK-PM group; c, SM-PM+SM group; d, CM-PM+CM group. DOC, soil dissolved organic carbon; TN, soil total nitrogen; MBC, soil microbial biomass carbon; MN, soil inorganic nitrogen. The arrow width is proportional to the strength of the path coefficients. The red solid arrows and blue dotted arrows indicate significant positive and negative correlations, respectively, while grey arrows indicate non-significant relationships. The stars *, ** and *** indicate significance at \u003cem\u003ep\u003c/em\u003e\u0026lt;0.05, 0.01 and 0.001, respectively.\u003c/p\u003e","description":"","filename":"floatimage7.png","url":"https://assets-eu.researchsquare.com/files/rs-7471631/v1/ce81489f635a612bfe958ec3.png"},{"id":93978323,"identity":"90817df1-ed82-45e3-ac7b-78041e4260d6","added_by":"auto","created_at":"2025-10-21 01:40:24","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":7519703,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7471631/v1/689fe1e4-2b4b-49f4-bdf5-2a30d54a01e6.pdf"},{"id":91411899,"identity":"9944c665-6911-4851-a152-4239c79eb9b1","added_by":"auto","created_at":"2025-09-16 08:52:10","extension":"docx","order_by":5,"title":"","display":"","copyAsset":false,"role":"supplement","size":198270,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryInformationPlantandSoil.docx","url":"https://assets-eu.researchsquare.com/files/rs-7471631/v1/035edb7c527a00145a15c043.docx"}],"financialInterests":"","formattedTitle":"Embedded biomass into topsoil as a green production mode to ensure soil structure and functions in arid irrigation region","fulltext":[{"header":"Introduction","content":"\u003cp\u003ePolyethylene mulching has broadly adopted as an efficient management practice to enhance crop yield by retaining soil moisture, suppressing weed, regulating soil temperature, and improving nutrient availability in arid and semi-arid agricultural regions (Ma et al., \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Liu et al., \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). However, the mechanisms underlying its productivity-enhancing effects have been linked to the depletion of soil organic carbon, posing potential threats to soil quality (Lee, 2019; Liu et al., \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Moreover, the extensive use of plastic mulching has raised growing concerns regarding plastic waste accumulation and soil pollution (Khalid et al., \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Zhao et al., \u003cspan citationid=\"CR62\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). Therefore, it is crucial to investigate sustainable alternatives to polyethylene mulching that can maintain soil quality and crop productivity while minimizing ecological risks (Scopetani et al., 2025).\u003c/p\u003e\u003cp\u003eNature-based mulching strategies, particularly those utilizing crop residues and living cover crops, present promising alternatives (Zhao et al., 2019; Zhang et al., \u003cspan citationid=\"CR59\" class=\"CitationRef\"\u003e2009\u003c/span\u003e). Crop residues, as a vital source of carbon and nutrients, have been shown to effectively maintain and accumulate soil organic carbon (Wang et al., \u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Zhao et al., \u003cspan citationid=\"CR61\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Compared to plastic mulching, crop residue mulching has been shown to enhance soil carbon and nitrogen composition in dryland winter wheat systems, while preserving soil microbial diversity (Hao et al., 2025; Fu et al., \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). Similarly, living mulches, typically cover crops grown concurrently with the main crop (e.g., white clover and purple vetch), offers a range of ecological and agronomic benefits (Cougnon et al., \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Hudson et al., \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). These systems prevent land degradation, reduce nutrient leaching, enhance soil structure, increase microbial biomass, and contribute organic matter (Alletto et al., \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Hudson et al., \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Leguminous cover crops, like clover, are particularly valuable for their biological nitrogen fixation capacity, which can significantly reduce the reliance on synthetic nitrogen fertilizers (Sui et al., \u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e2025\u003c/span\u003e; Alexander et al., \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2023\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eAdditionally, living mulching enhances soil stability by increasing water infiltration, microbial biomass, and organic matter content, ultimately contributing to higher crop yields (Djigal et al., \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2012\u003c/span\u003e). Specific living mulches like white clover and perennial ryegrass have been shown to directly improve soil aggregate stability (Qi et al., 2022; Holtham et al., \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2007\u003c/span\u003e; Elgersma et al., 1997). Furthermore, white clover is known to increase soil organic carbon and total nitrogen, improve soil enzyme activities (e.g., sucrase, urease, alkaline phosphatase), and enhance bacterial carbon metabolism and microbial community diversity (Wang et al., \u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; Lu et al., \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2025\u003c/span\u003e). Despite the established benefits of crop residue and living mulching in various systems, their comprehensive potential as direct substitutes for polyethylene film, particularly in arid irrigated regions heavily reliant on plastic, remains understudied. Understanding how embedded biomass, like shallow straw and living clover, impacts soil properties and yield compared to conventional plastic is vital for sustainable practices in these sensitive areas.\u003c/p\u003e\u003cp\u003eAddressing this critical gap, this study aimed to comprehensively evaluate the potential of embedded biomass mulching (including shallow-incorporated straw mulching and living clover mulching) as a substitute for polyethylene film from the perspective of soil quality. The research objectives were: (1) Investigate the impact of different embedded biomass mulching treatments on soil structure and aggregate stability.(2) Assess the effects of embedded biomass mulching on soil nutrient dynamics and organic carbon fractions.(3) Elucidate the responses of soil microbial biomass and key enzyme activities to embedded biomass mulching.(4) Determine the regulatory mechanisms by which embedded biomass mulching influences soil quality parameters and ultimately affects crop yield formation.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003eSite description and experiment design\u003c/h2\u003e\u003cp\u003eA two-year field experiment (2019 and 2020) was conducted in Jinchang City, located in the central region of the Hexi Corridor in Gansu Province, northwestern China. The experimental site was positioned at coordinates 38\u0026deg;15\u0026prime;-39\u0026deg;00\u0026prime;N and 102\u0026deg;15\u0026prime;-102\u0026deg;43\u0026prime;E, at an altitude of approximately 1430 meters above sea level. The daily maximum and minimum air temperatures, as well as precipitation dynamics during the 2019 and 2020 growing seasons, are presented in Fig. \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e. The background values of the soil are also shown in Fig. \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e.\u003c/p\u003e\u003cp\u003eThe experiment consisted of six treatments: (1) CK, no mulching; (2) SM, maize straw embedding mulching (12 t ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e); (3) CM, living clover embedding mulching (120 kg ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e); (4) PM, pure plastic film mulching; (5) PM\u0026thinsp;+\u0026thinsp;SM, plastic film mulching combined with maize straw embedding; and (6) PM\u0026thinsp;+\u0026thinsp;CM, plastic film mulching combined with living clover embedding. The experiment utilized a randomized complete block design. Each experimental plot measured 25 m\u0026sup2; (5 m by 5 m). The plots were established in a ridge-and-furrow configuration, featuring alternating wide ridges (10 cm in height and 70 cm in width) and narrow ridges (15 cm in height and 40 cm in width). For the SM treatment, maize straw pieces were mulched on the ridges and subsequently covered with soil. In the CM treatment, white clover (Trifolium repens L.) seeds were directly sown onto the ridges. For the PM treatment, the ridges were mulched with a transparent polyethylene film of 0.01 mm thickness. In the PM\u0026thinsp;+\u0026thinsp;SM and PM\u0026thinsp;+\u0026thinsp;CM treatments, this transparent film was combined with either maize straw incorporation or the establishment of living clover, respectively.\u003c/p\u003e\u003cp\u003eThe maize variety \u0026ldquo;Xianyu1225\u0026rdquo; was planted on April 26, 2019, and April 24, 2020, with harvest dates on September 28, 2019, and October 7, 2020, respectively. During both growing seasons, all plots received the same basal fertilization: 205 kg ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e of nitrogen (N), 248 kg ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e of phosphorus (P₂O₅), and 60 kg ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e of potassium (K₂O). To align with local irrigation practices, a total irrigation amount of 540 mm was applied across six growth stages during each growing season. Plants were managed using conventional pest, disease, and weed control methods.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eCrop yield\u003c/h3\u003e\n\u003cp\u003eAt physiological maturity, four complete and representative maize rows were chosen from each plot for yield parameter measurements.\u003c/p\u003e\n\u003ch3\u003eSoil parameters determination\u003c/h3\u003e\n\u003cp\u003eIn both years, after maize harvesting, soil samples were collected from each plot 0\u0026ndash;20 cm and 20\u0026ndash;40 cm depths. A portion of the collected soil samples was naturally air-dried and passed through a 0.15 mm sieve for the determination of soil organic carbon (SOC) and total nitrogen (TN). For the analysis of soil pH, easily oxidizable organic carbon (EOC), and particulate organic carbon (POC), samples were sieved through a 2 mm mesh. Another subset of soil samples was promptly transported to the laboratory and stored at -20 ℃ for subsequent analyses, including soil ammonium nitrogen (NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e-N), nitrate nitrogen (NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e-N), microbial biomass carbon (MBC) and nitrogen (MBN), dissolved organic carbon (DOC), dissolved organic nitrogen (DON), dissolved organic matter (DOM), urease activity (URE), and β-glucosidase activity (BG). The undisturbed soil samples were harvested to determine soil bulk density and water-stable aggregates. More details about soil properties determination are given in supplementary files (Section S1).\u003c/p\u003e\n\u003ch3\u003eStatical analysis\u003c/h3\u003e\n\u003cp\u003eAll statistical analyses were conducted using SPSS 22.0 (SPSS Inc., Chicago, USA). Analysis of variance (ANOVA) was employed to evaluate significant differences among treatments. Graphs and figures were generated with Origin 2021. To explore the relationships between soil physicochemical characteristics and crop yield, structural equation modeling (SEM) was applied.\u003c/p\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\u003ch2\u003eChanges in the soil pH and bulk density under different mulching treatments\u003c/h2\u003e\u003cp\u003eDifferent mulching treatments had significant effects on soil pH in the 0\u0026ndash;20 cm and 20\u0026ndash;40 cm depths (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ea-d). In comparison to PM and CK, SM and CM reduced soil pH in the 0\u0026ndash;20 cm depth in 2019 (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05) and 2020 (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05). In the 20\u0026ndash;40 cm soil layer, SM significantly decreased soil pH compared to PM. No significant difference between the dual-mulching treatment and PM was noticed.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eStraw mulching significantly affects soil bulk density in the 0\u0026ndash;20 cm and 20\u0026ndash;40 cm soil layers (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ee-h). In both growing seasons, under the SM treatment, the bulk density in the 0\u0026ndash;20 cm soil layer was 1.36 g cm\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e and 1.41 g cm\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e, respectively. Compared to CK, the SM treatment significantly reduced the bulk density in the 0\u0026ndash;20 cm soil layer by 12.2%-14.6%, and in 2020, it also significantly reduced the bulk density in the 20\u0026ndash;40 cm soil layer by 9.8%. No significant differences were observed among the other mulching treatments.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eChanges in the soil aggregates composition in different mulching treatments\u003c/h3\u003e\n\u003cp\u003eDifferent mulching treatments significantly influenced the proportion of soil aggregates (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). In the 0\u0026ndash;20 cm soil layer, compared to the CK treatment, all mulching treatments increased the proportion of large aggregates (\u0026gt;\u0026thinsp;2 mm). Compared to the PM treatment, the SM treatment had a 45.2% increase in the proportion of macroaggregates (\u0026gt;\u0026thinsp;2 mm), while PM\u0026thinsp;+\u0026thinsp;CM and PM\u0026thinsp;+\u0026thinsp;SM increased by 29.6% and 20.0%, respectively (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ea). In the 20\u0026ndash;40 cm soil layer, PM\u0026thinsp;+\u0026thinsp;SM exhibited a significant increase in the proportion of macroaggregates, followed by PM, PM\u0026thinsp;+\u0026thinsp;CM, and PM compared with CK. However, CM showed a decrease of 17.4% in the proportion of macroaggregates. Compared to the PM treatment, PM\u0026thinsp;+\u0026thinsp;SM had an 11% increase in the proportion of macroaggregates, while CM, SM, and PM\u0026thinsp;+\u0026thinsp;CM showed reductions of 59.3%, 45.7%, and 17.3%, respectively (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ec). The changes in the geometric mean diameter index (GMD) for the 0\u0026ndash;20 cm and 20\u0026ndash;40 cm soil layers followed a similar trend to the composition of macroaggregates (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eb, d).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\n\u003ch3\u003eChange in the soil organic carbon and total nitrogen\u003c/h3\u003e\n\u003cp\u003eSoil organic carbon (SOC) and total nitrogen (TN) was decreased with the increase of soil depth (Table. 1). The SM and PM\u0026thinsp;+\u0026thinsp;SM treatment significantly increased SOC 16.0% and 20.0% in the 0\u0026ndash;20 cm soil layer compared to CK and with 16.9% and 20.9% increase compared to PM, respectively. The clover-involved treatment did not show significant differences in SOC compared with CK and PM. In the 20\u0026ndash;40 cm soil layer, PM\u0026thinsp;+\u0026thinsp;SM treatment enhanced SOC by 7.5% in compared to CK.\u003c/p\u003e\u003cp\u003eIn the 0\u0026ndash;20 cm soil layer, PM\u0026thinsp;+\u0026thinsp;SM soil total nitrogen content was increased by 4.7% and 5.3% compared with CK and PM. The CM had a 4.4% increase in TN compared to PM. The different mulching treatments did not significantly impact on TN in the 0\u0026ndash;40 cm soil layer. Changes in SOC and TN altered C/N ratio. In the 0\u0026ndash;20 cm soil layer, SM and PM\u0026thinsp;+\u0026thinsp;SM resulted in a 12.8% and 15.2% higher C/N ratio, compared with CK (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Additionally, PM\u0026thinsp;+\u0026thinsp;SM also increased the C/N ratio in the 20\u0026ndash;40 cm soil layer by approximately 6.7% (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05) (Table. 1).\u003c/p\u003e\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\u003ch2\u003eChanges in the soil labile organic carbon and nitrogen fractions\u003c/h2\u003e\u003cp\u003eBoth SM and CM substantially increased the dissolved organic carbon (DOC) content in the 0\u0026ndash;20 cm and 20\u0026ndash;40 cm soil layers (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). However, significant differences were noticed in the second growing season compared with CK. Compared with PM, PM\u0026thinsp;+\u0026thinsp;SM significantly increased the DOC content by 11.8% and 13.0% in the 0\u0026ndash;20 cm and 20\u0026ndash;40 cm soil layers respectively, while PM\u0026thinsp;+\u0026thinsp;CM did not show significant differences compared to PM. Overall, PM\u0026thinsp;+\u0026thinsp;SM had the highest DOC content (71.1 mg kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e), followed by SM (66.5 mg kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) and CM (64.9 mg kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eIn the 0\u0026ndash;20 cm soil layer, SM and PM\u0026thinsp;+\u0026thinsp;SM had higher particulate organic carbon (POC) content than CK and PM, while no significant differences were observed between SM, PM\u0026thinsp;+\u0026thinsp;SM, and CM. In the 20\u0026ndash;40 cm soil layer, there were no significant differences in POC content among the treatments (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ee-h). Compared to CK and PM, SM significantly increased the easily oxidizable organic carbon (EOC) content in the 0\u0026ndash;20 cm and 20\u0026ndash;40 cm soil layers (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ei-l). The UV/Visible absorption spectra of dissolved organic matter (DOM) were influenced by the mulching treatments (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). In the 0\u0026ndash;20 cm soil layer, PM\u0026thinsp;+\u0026thinsp;CM exhibited the highest content of SUV254, SUV280, and SUV365, followed by CM, while PM\u0026thinsp;+\u0026thinsp;SM had the lowest content. In the 20\u0026ndash;40 cm soil layer, PM and PM\u0026thinsp;+\u0026thinsp;SM had the lowest content of SUV254, SUV280, and SUV365, with no significant difference between them.\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\u003eVariations of soil organic carbon (SOC), total nitrogen (TN), C/N and spectral characteristics of soluble organic matter (SUVA254, SUVA280 and SUVA365) in the 0\u0026ndash;20 cm and 20\u0026ndash;40 cm soil layers under different treatments.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"8\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSoil depth\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTreatments\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eSOC (g kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eTN (g kg \u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eC/N\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eSUVA254\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eSUVA280\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u003cp\u003eSUVA365\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"5\" rowspan=\"6\"\u003e\u003cp\u003e0\u0026ndash;20 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eCK\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6.31\u0026thinsp;\u0026plusmn;\u0026thinsp;0.23 b\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.344\u0026thinsp;\u0026plusmn;\u0026thinsp;0.002 bc\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e18.28\u0026thinsp;\u0026plusmn;\u0026thinsp;0.56 b\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e3.20\u0026thinsp;\u0026plusmn;\u0026thinsp;0.15 c\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e2.46\u0026thinsp;\u0026plusmn;\u0026thinsp;0.08 b\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.88\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04 bc\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSM\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e7.32\u0026thinsp;\u0026plusmn;\u0026thinsp;0.35 a\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.355\u0026thinsp;\u0026plusmn;\u0026thinsp;0.003 ab\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e20.62\u0026thinsp;\u0026plusmn;\u0026thinsp;0.84 a\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e3.24\u0026thinsp;\u0026plusmn;\u0026thinsp;0.06 c\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e2.50\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03 b\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.84\u0026thinsp;\u0026plusmn;\u0026thinsp;0.02 c\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eCM\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6.55\u0026thinsp;\u0026plusmn;\u0026thinsp;0.20 b\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.357\u0026thinsp;\u0026plusmn;\u0026thinsp;0.004 ab\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e18.37\u0026thinsp;\u0026plusmn;\u0026thinsp;0.77 b\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e3.54\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09 b\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e2.72\u0026thinsp;\u0026plusmn;\u0026thinsp;0.05 a\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.95\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03 b\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePM\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6.26\u0026thinsp;\u0026plusmn;\u0026thinsp;0.14 b\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.342\u0026thinsp;\u0026plusmn;\u0026thinsp;0.005 bc\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e18.28\u0026thinsp;\u0026plusmn;\u0026thinsp;0.17 b\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e2.69\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12 d\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e2.10\u0026thinsp;\u0026plusmn;\u0026thinsp;0.08 c\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.81\u0026thinsp;\u0026plusmn;\u0026thinsp;0.01 c\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePM\u0026thinsp;+\u0026thinsp;SM\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e7.57\u0026thinsp;\u0026plusmn;\u0026thinsp;0.17 a\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.360\u0026thinsp;\u0026plusmn;\u0026thinsp;0.003 a\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e21.06\u0026thinsp;\u0026plusmn;\u0026thinsp;0.63 a\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e2.40\u0026thinsp;\u0026plusmn;\u0026thinsp;0.07 e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e1.87\u0026thinsp;\u0026plusmn;\u0026thinsp;0.05 d\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.70\u0026thinsp;\u0026plusmn;\u0026thinsp;0.01 d\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePM\u0026thinsp;+\u0026thinsp;CM\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6.25\u0026thinsp;\u0026plusmn;\u0026thinsp;0.17 b\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.347\u0026thinsp;\u0026plusmn;\u0026thinsp;0.004 bc\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e18.02\u0026thinsp;\u0026plusmn;\u0026thinsp;0.69 b\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e4.23\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03 a\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e3.32\u0026thinsp;\u0026plusmn;\u0026thinsp;0.05 a\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e1.17\u0026thinsp;\u0026plusmn;\u0026thinsp;0.02 a\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"5\" rowspan=\"6\"\u003e\u003cp\u003e20\u0026ndash;40 cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eCK\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5.63\u0026thinsp;\u0026plusmn;\u0026thinsp;0.16 b\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.279\u0026thinsp;\u0026plusmn;\u0026thinsp;0.002 a\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e20.19\u0026thinsp;\u0026plusmn;\u0026thinsp;0.50 b\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e4.49\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12 b\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e3.46\u0026thinsp;\u0026plusmn;\u0026thinsp;0.10 b\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e1.25\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03 b\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSM\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6.01\u0026thinsp;\u0026plusmn;\u0026thinsp;0.14 ab\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.284\u0026thinsp;\u0026plusmn;\u0026thinsp;0.004 a\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e21.18\u0026thinsp;\u0026plusmn;\u0026thinsp;0.22 ab\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e3.40\u0026thinsp;\u0026plusmn;\u0026thinsp;0.25 c\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e2.61\u0026thinsp;\u0026plusmn;\u0026thinsp;0.21 c\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.98\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09 c\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eCM\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5.78\u0026thinsp;\u0026plusmn;\u0026thinsp;0.08 ab\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.283\u0026thinsp;\u0026plusmn;\u0026thinsp;0.004 a\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e20.42\u0026thinsp;\u0026plusmn;\u0026thinsp;0.45 ab\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e4.41\u0026thinsp;\u0026plusmn;\u0026thinsp;0.19 b\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e3.43\u0026thinsp;\u0026plusmn;\u0026thinsp;0.15 b\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e1.31\u0026thinsp;\u0026plusmn;\u0026thinsp;0.05 b\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePM\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5.68\u0026thinsp;\u0026plusmn;\u0026thinsp;0.15 ab\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.276\u0026thinsp;\u0026plusmn;\u0026thinsp;0.003 a\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e20.57\u0026thinsp;\u0026plusmn;\u0026thinsp;0.43 ab\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e2.77\u0026thinsp;\u0026plusmn;\u0026thinsp;0.00 d\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e2.13\u0026thinsp;\u0026plusmn;\u0026thinsp;0.00 c\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.78\u0026thinsp;\u0026plusmn;\u0026thinsp;0.00 c\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePM\u0026thinsp;+\u0026thinsp;SM\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6.05\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09 a\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.281\u0026thinsp;\u0026plusmn;\u0026thinsp;0.006 a\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e21.54\u0026thinsp;\u0026plusmn;\u0026thinsp;0.32 a\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e3.16\u0026thinsp;\u0026plusmn;\u0026thinsp;0.11 cd\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e2.40\u0026thinsp;\u0026plusmn;\u0026thinsp;0.08 c\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.82\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03 c\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePM\u0026thinsp;+\u0026thinsp;CM\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5.73\u0026thinsp;\u0026plusmn;\u0026thinsp;0.06 ab\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.278\u0026thinsp;\u0026plusmn;\u0026thinsp;0.005 a\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e20.65\u0026thinsp;\u0026plusmn;\u0026thinsp;0.33 ab\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e6.04\u0026thinsp;\u0026plusmn;\u0026thinsp;0.01 a\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e4.20\u0026thinsp;\u0026plusmn;\u0026thinsp;0.34 a\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e1.74\u0026thinsp;\u0026plusmn;\u0026thinsp;0.15 a\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"8\"\u003eNotes: CK, not any mulching; SM, maize straw piece embedding mulching; CM, living clover embedding mulching; PM, pure plastic film mulching; PM\u0026thinsp;+\u0026thinsp;SM, plastic film mulching with maize straw piece embedding; PM\u0026thinsp;+\u0026thinsp;CM, plastic film mulching with living clover embedding. Different lower-case letters indicate the significant differences at p\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eIn the 0\u0026ndash;20 cm soil layer, CM had the highest dissolved organic nitrogen (DON) content. In 2020, CM had 23.9% and 18.5% higher DON compared with CK and PM, respectively (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05). In the 20\u0026ndash;40 cm soil layer, PM\u0026thinsp;+\u0026thinsp;SM had a significantly higher DON than other treatments in 2019. In the second growing season, SM, CM, PM\u0026thinsp;+\u0026thinsp;SM, and PM\u0026thinsp;+\u0026thinsp;CM accumulated higher DON compared over CK and PM (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ea-d). PM\u0026thinsp;+\u0026thinsp;SM resulted in higher NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e-N content in the 0\u0026ndash;20 cm soil layer compared with other counterparts (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ee, f). However, the NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e-N content in the 20\u0026ndash;40 cm soil layer varied between years. In 2019, no significant differences in NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e-N content were observed among the treatments. In 2020, CM and PM\u0026thinsp;+\u0026thinsp;CM had significantly higher NH\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e+\u003c/sup\u003e-N levels compared with CK and PM (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eg, h). The trends in NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e-N content in the 0\u0026ndash;20 cm and 20\u0026ndash;40 cm soil layers were consistent throughout the growing season, with higher levels of NO\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e-N observed in SM and PM\u0026thinsp;+\u0026thinsp;SM. Overall, SM, CM, and PM\u0026thinsp;+\u0026thinsp;SM exhibited higher levels of soluble organic nitrogen and inorganic nitrogen (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ei-l).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\u003ch2\u003eSoil microbial biomass response to different mulching\u003c/h2\u003e\u003cp\u003eIn both years, PM\u0026thinsp;+\u0026thinsp;SM and PM\u0026thinsp;+\u0026thinsp;CM had increased the MBC content by 64.5% and 20.6% compared to PM in the 0\u0026ndash;20 cm soil layer (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05) (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003ea, b). In the 20\u0026ndash;40 cm soil layer, the MBC content of SM, CM, and CK was slightly higher than PM\u0026thinsp;+\u0026thinsp;SM, PM\u0026thinsp;+\u0026thinsp;CM, and PM. In 2020, the MBC content of SM, PM\u0026thinsp;+\u0026thinsp;SM, and CM was increased by 79.6%, 64.3%, and 56.9%, respectively, compared with PM (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05) (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003ec, d). Additionally, in the 0\u0026ndash;20 cm soil layer, PM\u0026thinsp;+\u0026thinsp;SM and PM\u0026thinsp;+\u0026thinsp;CM also had higher MBN than other treatments and CK (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003ee, f). In the 20\u0026ndash;40 cm soil layer, the MBN content showed a similar trend as MBC (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eg, h).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\u003ch2\u003eSoil enzyme activities in response to different mulching\u003c/h2\u003e\u003cp\u003eThe activity of soil urease was decreased with the increase of soil depth. In the 0\u0026ndash;20 cm soil layer, no significant difference was observed in 2019, however, CM, PM, and PM\u0026thinsp;+\u0026thinsp;SM showed the highest urease activity in 2020, while PM\u0026thinsp;+\u0026thinsp;CM had the lowest urease activity in both growing seasons (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003ea, b). In the 20\u0026ndash;40 cm soil layer, CM and PM displayed relatively higher urease activity (49.4 \u0026micro;g g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 48.7 \u0026micro;g g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e), respectively, while PM\u0026thinsp;+\u0026thinsp;CM exhibits the lowest urease activity, but with no significant difference from SM and CK (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003ec, d).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eHowever, PM\u0026thinsp;+\u0026thinsp;CM generally exhibited the highest β-glucosidase activity in the 0\u0026ndash;20 cm soil layer, followed by CM, and CK. The single biomass mulching showed significantly higher β-glucosidase activity compared to CK. Under dual-mulching, β-glucosidase activity was higher than PM, with the order of PM\u0026thinsp;+\u0026thinsp;CM\u0026thinsp;\u0026gt;\u0026thinsp;PM\u0026thinsp;+\u0026thinsp;SM\u0026thinsp;\u0026gt;\u0026thinsp;PM (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003ee, f). The β-glucosidase activity in the 20\u0026ndash;40 cm soil layer followed a similar trend as in the 0\u0026ndash;20 cm layer. Furthermore, urease and β-glucosidase activity were decreased with the increased soil depth (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003eg, h).\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e\u003ch2\u003eRelationship between soil factors and maize yield\u003c/h2\u003e\u003cp\u003eIn 2019, maize yield under biomass mulching (SM and CM) was increased by 22.0% and 20.9%, respectively, compared with CK. The plastic-involved mulching (PM, PM\u0026thinsp;+\u0026thinsp;SM and PM\u0026thinsp;+\u0026thinsp;CM) resulted in 17.1%, 15.8%, and 9.7%, higher respectively, compared to CK. In 2020, compared to CK, the grain yield under SM and CM was increased by 11.2% and 13.7%, respectively. Under plastic-involved mulching, yield was averagely increase of 11.2% relative to CK. Similar trends were also observed for water use efficiency (WUE) in both years (Table \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eBy conducting correlation analysis and principal component analysis, indicators needed for the structural equation model were selected to examine the relationships between soil factors and crop yield (Table S2, S3, S4; Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e). The model fitted well with the data from all treatments, meeting the established criteria (χ2\u0026thinsp;=\u0026thinsp;0.09, df\u0026thinsp;=\u0026thinsp;1, p\u0026thinsp;=\u0026thinsp;0.764, CFI\u0026thinsp;=\u0026thinsp;1.00, GFI\u0026thinsp;=\u0026thinsp;1.00, RMSEA\u0026thinsp;\u0026lt;\u0026thinsp;0.001), indicating a good fit of the model to the data. The TN and MBC were positively correlated with yield (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003ea), explaining a 31% variation in yield. Furthermore, MBC, enzyme activity, and inorganic nitrogen displayed 5%, 19%, and 48% variation, respectively. In the CK-PM treatment, the model exhibited satisfactory parameter values with χ2\u0026thinsp;=\u0026thinsp;0.925, df\u0026thinsp;=\u0026thinsp;2, p\u0026thinsp;=\u0026thinsp;0.630, CFI\u0026thinsp;=\u0026thinsp;1.00, GFI\u0026thinsp;=\u0026thinsp;0.98, and RMSEA\u0026thinsp;\u0026lt;\u0026thinsp;0.001. This model accounted for 60% of the variation in crop yield. TN had a negative correlation with soil enzyme activity and yield, with the coefficients of -0.70 (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and \u0026minus;\u0026thinsp;0.28 (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.01), respectively. MBC and mineralized nitrogen (MN) had also negative correlations, while MBC positively influenced soil enzyme activity and yield (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003eb).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eIn the straw-involved treatment, SM-PM\u0026thinsp;+\u0026thinsp;SM, the model showed acceptable parameter values with χ2\u0026thinsp;=\u0026thinsp;2.211, df\u0026thinsp;=\u0026thinsp;2, p\u0026thinsp;=\u0026thinsp;0.331, CFI\u0026thinsp;=\u0026thinsp;1.00, GFI\u0026thinsp;=\u0026thinsp;0.96, and RMSEA\u0026thinsp;=\u0026thinsp;0.079. This model explained 37% of the variation in crop yield. TN exhibited a negative correlation with MN and yield, and DOC had a negative correlation with MBC. However, MBC had a significant positive effect on enzyme activity, MN, and crop yield (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003ec). In contrast to the straw-involved treatment, the CM-PM\u0026thinsp;+\u0026thinsp;CM model exhibited significant positive correlations between TN and yield, as well as between MN and crop yield. Moreover, TN showed negative correlations with MBC and MN, respectively. The established model had the following parameters: χ2\u0026thinsp;=\u0026thinsp;0.483, df\u0026thinsp;=\u0026thinsp;2, p\u0026thinsp;=\u0026thinsp;0.785, CFI\u0026thinsp;=\u0026thinsp;1.00, GFI\u0026thinsp;=\u0026thinsp;0.97, and RMSEA\u0026thinsp;\u0026lt;\u0026thinsp;0.001. It accounted for 46% of the variation in crop yield (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003ed).\u003c/p\u003e\u003c/div\u003e"},{"header":"Discussion","content":"\u003cdiv id=\"Sec16\" class=\"Section2\"\u003e\u003ch2\u003eEffects of mulching on soil bulk density and aggregate distribution\u003c/h2\u003e\u003cp\u003eSoil bulk density is a key indicator of soil structure quality and mineral content (H\u0026aring;kansson et al., 2000). Straw return can improve soil aggregate structure, increase soil porosity, and benefit the activity and reproduction of aerobic microorganisms by improving soil permeability, thereby making soil looser and reducing soil bulk density (Ram et al., \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e2013\u003c/span\u003e). In the present study, straw mulching exhibited similar effects to straw return. During the second year, the residual straw from the previous year underwent decomposition and was gradually incorporated into the soil profile. This process notably reduced the soil bulk density at the 20\u0026ndash;40 cm soil layer (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). These findings suggest that straw mulching not only exerts short-term benefits but also contributes to long-term improvement in soil physical properties through its decomposition and integration into the soil (Wang et al., \u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e2023\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eSoil organic matter (SOM) plays a critical role as the primary adhesive agent in the formation and stabilization of soil aggregates (Oades et al., 1984). It is closely associated with aggregate stability, which influences soil structure and function (Six et al., \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e2004\u003c/span\u003e; Whitbread et al., 1995; Artemyeva et al., \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Straw incorporation has been widely recognized as an effective strategy to enhance SOM levels, thereby increasing the contribution of surface aggregates to soil organic carbon (SOC) accumulation (Huang et al., \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). Consistent with these findings, our study demonstrated that SOC in the 0\u0026ndash;20 cm soil layer was significantly higher in SM and PM\u0026thinsp;+\u0026thinsp;SM treatments compared to other treatments (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). This enhancement in SOC was accompanied by a notable increase in the proportion of macroaggregates (\u0026gt;\u0026thinsp;2 mm), which improved soil aggregate stability (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eIn addition to organic matter, active iron oxides, including Feo (amorphous iron oxide) and Fep (free iron oxide), serve as crucial adhesive agents that facilitate aggregate stabilization, particularly following the incorporation of organic matter (Asano et al., 2014; Xue et al., \u003cspan citationid=\"CR53\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Straw incorporation significantly increased the content of iron oxides in the soil, further contributing to aggregate stability (Xue et al., \u003cspan citationid=\"CR53\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Moreover, the continuous input of straw via surface burial and associated materials created favorable conditions for microbial activity (Yang et al., \u003cspan citationid=\"CR54\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Microbial decomposition of straw residues and root exudates released bioproducts such as fungal hyphae and bacterial polysaccharides, which enhanced the aggregation of clay and silt particles by acting as temporary binding agents (Lehmann et al., \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2017\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eOur findings further revealed that PM\u0026thinsp;+\u0026thinsp;SM increased soil temperature, which stimulated microbial activity and accelerated straw decomposition (Jin et al., \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). This resulted in greater input of organic matter into the soil, promoting the formation of larger soil aggregates (Ma et al., \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). However, in the 0\u0026ndash;20 cm soil layer, SM alone contributed more to macroaggregate formation compared to PM\u0026thinsp;+\u0026thinsp;SM (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). he observed differences can be explained by the progressive decomposition of residual straw incorporated in the SM treatment during the previous growing season (2019). The ongoing breakdown of these residues contributed to a steady release of organic matter into the soil, thereby promoting the formation and stabilization of soil macroaggregates. Conversely, the PM\u0026thinsp;+\u0026thinsp;SM treatment contained a comparatively lower amount of residual straw from 2019, resulting in reduced organic matter input and subsequently a weaker effect on macroaggregate development.\u003c/p\u003e\u003cp\u003eThe dynamic and interactive effects of SOM, microbial activity, and external inputs highlight the importance of optimizing residue management practices to improve soil structure and stability (Bhattacharyya et al., \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). Recent studies have emphasized the synergistic role of straw-derived organic amendments and microbial interactions in fostering soil aggregation and enhancing soil functionality (Chen et al., \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Wu et al., \u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). For instance, straw decomposition not only supplies organic matter but also modifies soil microenvironmental conditions, creating niches for microbial communities that contribute to aggregate stabilization through biogenic adhesive compounds (Guo et al., \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). These observations align with the results of our study and reinforce the critical importance of residue incorporation in sustainable soil management.\u003c/p\u003e\u003cp\u003eAdditionally, fresh organic matter has been widely recognized for its ability to enhance microbial activity and improve soil aggregate stability (Fontaine et al., \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2007\u003c/span\u003e). In this study, the CM treatment increased the proportion of macroaggregates in the 0\u0026ndash;20 cm soil layer but resulted in a decrease in the 20\u0026ndash;40 cm soil layer (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). This reduction can be attributed to the activity of clover roots, which influenced soil aggregation dynamics. Specifically, low C/N ratio root residues from clover accelerated the mineralization of soil organic matter, leading to localized carbon depletion and subsequent disruption of macroaggregates (Fr\u0026oslash;seth et al., \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Six et al., \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e2004\u003c/span\u003e). Despite this reduction, the shift in aggregate size was relatively minor, with aggregates only transitioning from 0.5-1 mm to macroaggregates (\u0026gt;\u0026thinsp;2 mm) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Importantly, the overall percentage of aggregates larger than 0.25 mm remained stable. As a result, both the aggregate stability index and the geometric mean diameter (GMD) of the CM treatment were higher compared to CK, suggesting that clover improved soil quality through modifications to the aggregate size distribution and composition.\u003c/p\u003e\u003cp\u003eSpecifically, the proportion of carboxyl groups and the ratio of low aromatic ring compounds in soil organic matter play a crucial role in aggregate formation (Verchot et al., \u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e2011\u003c/span\u003e). The input of fresh organic matter typically increases the proportion of carboxyl groups while decreasing the proportion of stable aromatic organic matter (Ndzelu et al., \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). However, in this study, PM\u0026thinsp;+\u0026thinsp;CM not only increased the proportion of soil macroaggregates (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e), but also significantly increased the content of high molecular weight aromatic compounds in the soluble organic matter fraction (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). This could be attributed to changes in the organic matter composition induced by clover under plastic film. Notably, the hydrophobic nature of aromatic compounds could form a hydrophobic protective layer around soil organic matter, preventing its microbial decomposition and enhancing aggregate stability (Semenov et al., \u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e2013\u003c/span\u003e). However, this differs from the effect of soluble aromatic compounds observed in this study, which have no hydrophobic properties. For example, a typical component of humic substances, fulvic acid, which contains a benzene ring and a carboxyl group had no negative impact on the aggregation of soil aggregates.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec17\" class=\"Section2\"\u003e\u003ch2\u003eChanges in soil chemistry under different mulching\u003c/h2\u003e\u003cp\u003eThe respiratory release of CO\u003csub\u003e2\u003c/sub\u003e by root systems has been shown to influence soil pH (Hinsinger et al., \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2003\u003c/span\u003e). In this study, SM and CM treatments significantly decreased soil pH compared to PM\u0026thinsp;+\u0026thinsp;SM, PM\u0026thinsp;+\u0026thinsp;CM, and PM treatments (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). This reduction was likely attributed to the higher root biomass and elevated root respiration rates in SM and CM (Table \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e), which resulted in substantial CO\u003csub\u003e2\u003c/sub\u003e emissions and subsequent soil acidification. Additionally, the secretion of acidic compounds, such as organic acids, by roots further contributed to the observed pH reduction (Zeng et al., \u003cspan citationid=\"CR57\" class=\"CitationRef\"\u003e2008\u003c/span\u003e). During the late growth stages of maize, the PM\u0026thinsp;+\u0026thinsp;SM, PM\u0026thinsp;+\u0026thinsp;CM, and PM treatments facilitated earlier plant maturity, which led to reduced root biomass and lower production of root exudates. This diminished the influence of root processes on soil pH, resulting in minimal changes. Notably, soil pH changes were more pronounced in 2019 compared to 2020, likely due to microbial community shifts induced by the biomass addition in 2019 (Table \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e). These shifts in microbial composition may have influenced organic matter decomposition rates and nutrient cycling processes, ultimately contributing to a more stable soil pH in 2020. This stabilization is indicative of negative feedback mechanisms and adaptation within the soil system (Pietri et al., 2009; Wang et al., 2024).\u003c/p\u003e\u003cp\u003eHowever, the elevated soil moisture and temperature associated with plastic film mulching can accelerate the mineralization of soil organic matter in irrigated areas, ultimately leading to a decline in soil organic carbon content (Yu et al., \u003cspan citationid=\"CR56\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). In both years of the study, the contribution of PM to soil organic carbon was similar to or lower than that of CK (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). In the irrigated regions of the Hexi Corridor, the maize root biomass input under PM practice was insufficient to offset the accelerated mineralization rate of soil organic matter. Prolonged exposure to high soil temperatures and moisture exacerbates the mineralization process, resulting in the depletion of soil organic carbon. These findings indicate that long-term polyethylene mulch cover is not a sustainable soil management practice in these regions (Steinmetz et al., \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). Moreover, the trend of organic carbon changes in the PM\u0026thinsp;+\u0026thinsp;CM was consistent with the PM treatment. Although clover contributed to organic matter input, higher temperature and moisture retention intensify the microbial mineralization of fresh organic matter (Whitman et al., \u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). This increased mineralization offset the positive contribution of clover to soil organic carbon, further illustrating the challenges of sustaining soil organic matter levels under mulching practices that exacerbate mineralization conditions.\u003c/p\u003e\u003cp\u003eFurthermore, the organic carbon content in the CM treatment was not significantly different from that in the PM\u0026thinsp;+\u0026thinsp;CM treatment but was slightly higher, possibly due to the absence of the PM layer, which may have catalyzed organic matter accumulation and decomposition processes. In addition, dual plastic and maize straw mulching (PM\u0026thinsp;+\u0026thinsp;SM) accelerated the straw decomposition rate. By the second year, the decomposed straw was incorporated into the soil, leading to an increase in soil organic carbon (SOC) content within the 0\u0026ndash;40 cm soil layer. Previous studies have demonstrated that decomposed straw serves as an effective soil amendment, contributing to improved soil fertility and carbon sequestration (Liang et al., \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Liu et al., \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). Notably, the SM treatment resulted in a marked increase in organic carbon content in the 0\u0026ndash;20 cm soil layer, likely due to the incorporation of partially decomposed straw, which raised the soil C/N ratio (Zhang et al., \u003cspan citationid=\"CR58\" class=\"CitationRef\"\u003e2015\u003c/span\u003e). The higher C/N ratio in SM limited nitrogen availability for microorganisms, reducing the decomposition and transformation of straw-derived organic matter compared to the PM\u0026thinsp;+\u0026thinsp;SM treatment. While excessive straw mulching can inhibit SOC accumulation by suppressing microbial activity, this typically occurs through mechanisms such as nitrogen immobilization caused by a high C/N ratio and reduced soil aeration limiting oxygen availability for microbial respiration (Mary et al., \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e1996\u003c/span\u003e; Guo et al., 2015). Additionally, the accumulation of intermediate decomposition products, such as organic acids, can further suppress microbial activity (Kuzyakov, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2010\u003c/span\u003e). In this study, however, no such inhibition was observed, suggesting that the applied straw mulching rate was appropriate to sustain microbial activity and promote SOC accumulation.\u003c/p\u003e\u003cp\u003eDissolved organic carbon (DOC) serves as a primary energy source for microorganisms, while microbial metabolites also contribute significantly to DOC pools (Fang et al., 2005). In this study, SM and PM\u0026thinsp;+\u0026thinsp;SM treatments significantly increased DOC content compared to CK and PM, primarily due to straw decomposition, which released substantial amounts of DOC, labile organic carbon, and nitrogen, thereby providing essential nutrients for microbial activity (Wang et al., \u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). Notably, PM\u0026thinsp;+\u0026thinsp;SM accelerated straw decomposition more effectively than SM alone, resulting in higher DOC levels. Additionally, both SM and PM\u0026thinsp;+\u0026thinsp;SM increased the contents of easily oxidizable carbon and particulate organic carbon (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e), highlighting straw mulching as an effective soil management practice for improving the fertility of low-nutrient farmland (Liu et al., \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). The enhanced carbon availability under SM and PM\u0026thinsp;+\u0026thinsp;SM stimulated microbial metabolism, promoting the release of additional nutrients and soluble organic compounds. These compounds further supported microbial growth, establishing a positive feedback loop that reinforced carbon turnover and nutrient cycling (Chen et al., \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2017\u003c/span\u003e; Yang et al., \u003cspan citationid=\"CR55\" class=\"CitationRef\"\u003e2018\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eIn this two-year study, changes in soil total nitrogen content were minimal, with significant differences observed only in the 0\u0026ndash;20 cm soil layer, where PM\u0026thinsp;+\u0026thinsp;SM significantly increased TN content. Straw incorporation is known to elevate the soil carbon-to-nitrogen (C/N) ratio due to high carbon inputs (Meng et al., \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). Consistent with this, our study found that both SM and PM\u0026thinsp;+\u0026thinsp;SM treatments significantly elevated the soil C/N ratio. In contrast, PM accelerated soil organic matter mineralization, leading to a reduction in the C/N ratio. Similarly, CM and PM\u0026thinsp;+\u0026thinsp;CM decreased the C/N ratio, likely due to clover\u0026rsquo;s contribution to soil nitrogen as an effective green manure source. Furthermore, dissolved organic nitrogen (DON) and inorganic nitrogen (e.g., NH4\u003csup\u003e+\u003c/sup\u003e-N) serve as active nitrogen sources for microbial processes. In 2019, there were no significant differences in DON andNH4\u003csup\u003e+\u003c/sup\u003e-N content between CM and CK in the 0\u0026ndash;20 cm soil layer, whereas significant differences appeared in 2020. This suggests that clover inputs organic matter into the soil during the first growing season, contributing to increased DON and NH4\u003csup\u003e+\u003c/sup\u003e-N content in the subsequent year. Variations in DON and NH4\u003csup\u003e+\u003c/sup\u003e-N content in the 20\u0026ndash;40 cm soil layer between years further highlight the interannual cumulative effects of single biomass covers, such as clover, on nitrogen dynamics.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec18\" class=\"Section2\"\u003e\u003ch2\u003eEffects of mulching on soil microbial biomass and enzyme dynamics\u003c/h2\u003e\u003cp\u003eAlthough microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) constitute a small fraction of soil organic carbon and total nitrogen, they are highly sensitive indicators of soil management practices (Franchini et al., \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2007\u003c/span\u003e). In this study, treatments involving organic inputs (SM, CM, PM\u0026thinsp;+\u0026thinsp;SM, and PM\u0026thinsp;+\u0026thinsp;CM) significantly increased soil MBC and MBN content compared to CK and PM. Biomass cover enhanced soil biochemical properties and stimulated microbial activity (Chen et al., \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2017\u003c/span\u003e). Notably, the cumulative effect of dual plastic and biomass mulching on microbial biomass was superior to that of sole biomass mulching, likely due to the improved water and heat conditions provided by the combined mulching, which fostered microbial activity. Furthermore, sole straw mulching contributed more to MBC, while sole clover mulching was more effective in increasing MBN, reflecting the distinct carbon and nitrogen composition of the respective biomass inputs.\u003c/p\u003e\u003cp\u003eIn general, plastic film mulching creates favorable hydrothermal conditions that accelerate biomass decomposition, thereby supplying carbon and nitrogen sources essential for soil microorganisms and enhancing soil enzyme activity (Tejada et al., 2014). Consistent with this, our study observed significant increases in urease activity under the PM\u0026thinsp;+\u0026thinsp;SM treatment and β-glucosidase activity under the PM\u0026thinsp;+\u0026thinsp;CM treatment. These differential effects of biomass mulching on soil enzyme activity may be linked to its impact on microbial community composition and structure. Additionally, our findings revealed that sole biomass mulching effectively increases the abundance of dominant phyla within soil bacterial and fungal communities, further influencing soil biochemical processes (Zhao et al., \u003cspan citationid=\"CR62\" class=\"CitationRef\"\u003e2022\u003c/span\u003e).\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec19\" class=\"Section2\"\u003e\u003ch2\u003eInteractions between soil properties and crop yield under mulching treatments\u003c/h2\u003e\u003cp\u003eAmong all treatments, biomass cover treatments (PM\u0026thinsp;+\u0026thinsp;SM, PM\u0026thinsp;+\u0026thinsp;CM, SM, CM) significantly enhanced soil organic matter (SOM) and total nitrogen (TN) content. Furthermore, the active components of SOM and nitrogen, such as dissolved organic carbon (DOC) and inorganic nitrogen (MN), also showed notable increases. This improvement can be attributed to the input of fresh organic matter from straw or clover and the favorable hydrothermal conditions created by the cover treatments, which stimulated microbial proliferation and soil enzyme activity (Akhtar et al., 2019). As a result, simultaneous increases were observed in DOC, TN, microbial biomass, soil enzyme activity, inorganic nitrogen, and ultimately, crop yield. Structural equation modeling (SEM) conducted for CK-PM, SM-PM\u0026thinsp;+\u0026thinsp;SM, and CM-PM\u0026thinsp;+\u0026thinsp;CM treatments revealed strong positive correlations between microbial biomass carbon (MBC) and soil enzyme activity, as well as between MBC and maize grain yield. This underscores the critical role of microbial biomass in driving soil biochemical processes, contributing to nutrient availability, and supporting crop productivity.\u003c/p\u003e\u003cp\u003eIn the SEM analysis of CK-PM, a significant negative correlation was observed between total nitrogen (TN) and both soil enzyme activity and grain yield, attributed to lower microbial activity and yield in CK compared to PM. The PM treatment, with higher microbial biomass, enhanced nitrogen mineralization, converting organic nitrogen in TN into plant-available inorganic nitrogen (Zhang et al., \u003cspan citationid=\"CR60\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). As a result, PM showed increased microbial biomass carbon (MBC), enzyme activity, and grain yield, despite lower TN and mineral nitrogen (MN) than CK. However, long-term polyethylene mulching disrupted nitrogen balance, reducing soil fertility and requiring increased nitrogen fertilizer application, which risks nitrogen loss and environmental pollution (Li et al., \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e2021\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eIn the SM-PM\u0026thinsp;+\u0026thinsp;SM group, crop residue decomposition provided continuous nitrogen inputs, promoting microbial nitrogen mineralization (Zhao et al., \u003cspan citationid=\"CR61\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). The PM\u0026thinsp;+\u0026thinsp;SM treatment accelerated residue decomposition, enhancing microbial growth through increased carbon input (Yang et al., \u003cspan citationid=\"CR55\" class=\"CitationRef\"\u003e2018\u003c/span\u003e), resulting in a positive correlation between microbial biomass carbon (MBC) and mineral nitrogen (MN). However, higher microbial biomass in PM\u0026thinsp;+\u0026thinsp;SM led to greater consumption of dissolved organic carbon (DOC), causing a significant negative correlation between DOC and MBC. These findings align with studies showing that elevated microbial activity can deplete DOC faster than its replenishment (Fang et al., 2005).\u003c/p\u003e\u003cp\u003eNo significant differences were found between PM\u0026thinsp;+\u0026thinsp;SM and SM treatments in grain yield, total nitrogen (TN), and mineral nitrogen (MN) content, indicating that the negative correlation between TN and grain yield, as well as TN and MN, is driven by intra-group variations rather than inter-group differences. Notably, TN was measured using the Kjeldahl method, which excludes nitrate and nitrite fractions (Jansson et al., 1982). The mineralization of TN to MN likely explains the negative correlation observed between TN and MN, consistent with previous findings (Zhang et al., \u003cspan citationid=\"CR60\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). Additionally, MN accounted for up to 95% of the variation in structural equation models, highlighting its strong linkage to microbial biomass dynamics (Li et al., \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e2021\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eIn the CM-PM\u0026thinsp;+\u0026thinsp;CM system, TN was significantly negatively correlated with MN, but the underlying mechanism differed from that in the SM-PM\u0026thinsp;+\u0026thinsp;SM system. The CM treatment, incorporating clover as a leguminous crop, enhanced soil total nitrogen (TN) through biological nitrogen fixation and incorporation via tillage (Parr et al., \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e2011\u003c/span\u003e). However, TN was lower in PM\u0026thinsp;+\u0026thinsp;CM compared to CM, likely due to accelerated nitrogen mineralization under the higher moisture and temperature conditions created by plastic film mulching, resulting in increased soil inorganic nitrogen (MN) levels (Yu et al., \u003cspan citationid=\"CR56\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Tejada et al., 2014). Additionally, in the clover system, TN exhibited a significant positive correlation with grain yield, attributed to the stable nitrogen input from clover roots and improved soil hydrothermal conditions provided by biomass mulching. These findings align with previous studies highlighting the role of leguminous cover crops in enhancing nitrogen availability and improving crop yield (Zhao et al., \u003cspan citationid=\"CR62\" class=\"CitationRef\"\u003e2022\u003c/span\u003e).\u003c/p\u003e\u003c/div\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThis study showed that both sole biomass mulching (SM, CM) and dual mulching with plastic film (PM\u0026thinsp;+\u0026thinsp;SM, PM\u0026thinsp;+\u0026thinsp;CM) significantly improved soil structure, nutrient status, and maize yield compared to bare land (CK) and conventional plastic film mulching (PM). PM\u0026thinsp;+\u0026thinsp;SM and PM\u0026thinsp;+\u0026thinsp;CM further enhanced macroaggregate formation, soil organic carbon, nitrogen cycling, microbial biomass, and enzyme activities, resulting in the highest yield and water use efficiency. Notably, sole biomass mulching (SM, CM) also delivered substantial improvements in soil quality and crop productivity without the environmental drawbacks of plastic film. These findings suggest that while dual mulching maximizes agronomic performance, sole biomass mulching represents a more sustainable and eco-friendly strategy for arid farmland management.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003ch2\u003eCompeting Interest Statement:\u003c/h2\u003e\u003cp\u003eAuthors declare that they have no competing interests.\u003c/p\u003e\u003c/p\u003e\u003ch2\u003eAuthor contributions:\u003c/h2\u003e\u003cp\u003eZ.Y. Zhao and P.Y. Wang: Conceptualization, Methodology, Data collection, Sample analysis, Data analysis, Writing-draft, Visualization. X.B. Xiong, J.C. Guo, W.S. Li, N. Chang, Y.L. Chen, X.L. Zhang, and N. Wang: Data collection, Data analysis. Y. Chen, H.Y. Tao: Supervision, Writing- review \u0026amp; editing, Validation. Y.C. Xiong (Corresponding author): Conceptualization, Investigation, Writing- review \u0026amp; editing, Supervision, Validation.\u003c/p\u003e\u003ch2\u003eAcknowledgements:\u003c/h2\u003e\u003cp\u003eThis work was supported by National Key R\u0026amp;D Program of China (2024YFC3713900), National Natural Science Foundation of China (32401418), Fundamental Research Funds for the Central Universities (lzujbky-2024-jdzx11, lzujbky-2025-13, -it22), and Science and Technology Project of Gansu Province of China (24JRRA494).\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAlexander J R, Baker J M, Gamble J D, Venterea R T, Spokas K A. Spatiotemporal distribution of roots in a Maize-Kura clover living mulch system: Impact of tillage and fertilizer N source. \u003cem\u003eSoil \u0026amp; Tillage Research\u003c/em\u003e, 2023, 227: 105590.\u003c/li\u003e\n\u003cli\u003eAlletto L, Cassigneul A, Duchalais A, et al. Cover crops maintain or improve agronomic performances of maize monoculture during the transition period from conventional to no-tillage. \u003cem\u003eField Crops Research\u003c/em\u003e, 2022, 283: 108540.\u003c/li\u003e\n\u003cli\u003eArtemyeva Z, Danchenko N, Kolyagin Y, et al. Chemical structure of soil organic matter and its role in aggregate formation in Haplic Chernozem under the contrasting land use variants. \u003cem\u003eCatena\u003c/em\u003e, 2021, 204: 105403.\u003c/li\u003e\n\u003cli\u003eAsano M, Wagai R. Evidence of aggregate hierarchy at micro-to submicron scales in an allophanic Andisol. \u003cem\u003eGeoderma\u003c/em\u003e, 2014, 216: 62-74.\u003c/li\u003e\n\u003cli\u003eBhattacharyya S S, Ros G H, Furtak K, et al. Soil carbon sequestration\u0026ndash;An interplay between soil microbial community and soil organic matter dynamics. \u003cem\u003eScience of the Total Environment\u003c/em\u003e, 2022, 815: 152928.\u003c/li\u003e\n\u003cli\u003eChen H, Hao Y, Ma Y, et al. Maize straw-based organic amendments and nitrogen fertilizer effects on soil and aggregate-associated carbon and nitrogen. \u003cem\u003eGeoderma\u003c/em\u003e, 2024, 443: 116820.\u003c/li\u003e\n\u003cli\u003eChen Z, Wang H, Liu X, et al. Changes in soil microbial community and organic carbon fractions under short-term straw return in a rice\u0026ndash;wheat cropping system. \u003cem\u003eSoil and Tillage Research\u003c/em\u003e, 2017, 165: 121-127.\u003c/li\u003e\n\u003cli\u003eCougnon M, Durand J L, Julier B, et al. Using perennial plant varieties for use as living mulch for winter cereals. A review. \u003cem\u003eAgronomy for Sustainable Development\u003c/em\u003e, 2022, 42: 110.\u003c/li\u003e\n\u003cli\u003eDjigal D, Saj S, Rabary B, et al. Mulch type affects soil biological functioning and crop yield of conservation agriculture systems in a long-term experiment in Madagascar. \u003cem\u003eSoil and Tillage Research\u003c/em\u003e, 2012, 118: 11-21.\u003c/li\u003e\n\u003cli\u003eElgersma A, Hassink J. Effects of white clover (\u003cem\u003eTrifolium repens\u003c/em\u003e L.) on plant and soil nitrogen and soil organic matter in mixtures with perennial ryegrass (\u003cem\u003eLolium perenne\u003c/em\u003e L.). \u003cem\u003ePlant and Soil\u003c/em\u003e, 1997, 197: 177-186.\u003c/li\u003e\n\u003cli\u003eFang C, Moncrieff J B. The variation of soil microbial respiration with depth in relation to soil carbon composition. \u003cem\u003ePlant and Soil\u003c/em\u003e, 2005, 268: 243-253.\u003c/li\u003e\n\u003cli\u003eFontaine S, Barot S, Barr\u0026eacute; P, et al. Stability of organic carbon in deep soil layers controlled by fresh carbon supply. \u003cem\u003eNature\u003c/em\u003e, 2007, 450: 277-280.\u003c/li\u003e\n\u003cli\u003eFontaine S, Mariotti A, Abbadie L. The priming effect of organic matter: a question of microbial competition? \u003cem\u003eSoil Biology and Biochemistry\u003c/em\u003e, 2003, 35: 837-843.\u003c/li\u003e\n\u003cli\u003eFranchini J C, Crispino C C, Souza R A, et al. Microbiological parameters as indicators of soil quality under various soil management and crop rotation systems in southern Brazil. \u003cem\u003eSoil and Tillage Research\u003c/em\u003e, 2007, 92(1-2): 18-29.\u003c/li\u003e\n\u003cli\u003eFr\u0026oslash;seth R B, Thorup-Kristensen K, Hansen S, et al. High N relative to C mineralization of clover leaves at low temperatures in two contrasting soils. \u003cem\u003eGeoderma\u003c/em\u003e, 2022, 406: 115483.\u003c/li\u003e\n\u003cli\u003eFu X, Wang J, Sainju U M, et al. Soil microbial community and carbon and nitrogen fractions responses to mulching under winter wheat. \u003cem\u003eApplied Soil Ecology\u003c/em\u003e, 2019, 139: 64-68.\u003c/li\u003e\n\u003cli\u003eGuo W, Zhang Y, Xu J, et al. Straw management and fertilization improve soil aggregate stability by inducing biological binding agents and specific keystone genera. Pedosphere, 2024, 34: 40-51.\u003c/li\u003e\n\u003cli\u003eH\u0026aring;kansson I, Lipiec J. A review of the usefulness of relative bulk density values in studies of soil structure and compaction. \u003cem\u003eSoil and Tillage Research\u003c/em\u003e, 2000, 53: 71-85.\u003c/li\u003e\n\u003cli\u003eHinsinger P, Plassard C, Tang C, et al. Origins of root-mediated pH changes in the rhizosphere and their responses to environmental constraints: a review. \u003cem\u003ePlant and Soil\u003c/em\u003e, 2003, 248: 43-59.\u003c/li\u003e\n\u003cli\u003eHoltham D A L, Matthews G P, Scholefield D S. Measurement and simulation of void structure and hydraulic changes caused by root-induced soil structuring under white clover compared to ryegrass. \u003cem\u003eGeoderma\u003c/em\u003e, 2007, 142: 142-151.\u003c/li\u003e\n\u003cli\u003eHuang R, Tian D, Liu J, et al. Responses of soil carbon pool and soil aggregates associated organic carbon to straw and straw-derived biochar addition in a dryland cropping mesocosm system. \u003cem\u003eAgriculture, Ecosystems \u0026amp; Environment\u003c/em\u003e, 2018, 265: 576-586.\u003c/li\u003e\n\u003cli\u003eHudson T B, Alford A M, Bilbo T R, et al. Living mulches reduce natural enemies when combined with frequent pesticide applications. \u003cem\u003eAgriculture, Ecosystems \u0026amp; Environment\u003c/em\u003e, 2023, 357: 108680.\u003c/li\u003e\n\u003cli\u003eJansson S L, Persson J. Mineralization and immobilization of soil nitrogen. \u003cem\u003eNitrogen in Agricultural Soils\u003c/em\u003e, 1982, 22: 229-252.\u003c/li\u003e\n\u003cli\u003eJin X, An T, Gall A R, et al. Enhanced conversion of newly-added maize straw to soil microbial biomass C under plastic film mulching and organic manure management. \u003cem\u003eGeoderma\u003c/em\u003e, 2018, 313: 154-162.\u003c/li\u003e\n\u003cli\u003eKhalid N, Aqeel M, Noman A, et al. Impact of plastic mulching as a major source of microplastics in agroecosystems. \u003cem\u003eJournal of Hazardous Materials\u003c/em\u003e, 2023, 445: 130455.\u003c/li\u003e\n\u003cli\u003eKuzyakov Y. Priming effects: interactions between living and dead organic matter. \u003cem\u003eSoil Biology and Biochemistry\u003c/em\u003e, 2010, 42: 1363-1371.\u003c/li\u003e\n\u003cli\u003eLee J G, Hwang H Y, Park M H, et al. Depletion of soil organic carbon stocks are larger under plastic film mulching for maize. \u003cem\u003eEuropean Journal of Soil Science\u003c/em\u003e, 2019, 70: 807-818.\u003c/li\u003e\n\u003cli\u003eLehmann A, Zheng W, Rillig M C. Soil biota contributions to soil aggregation. \u003cem\u003eNature Ecology \u0026amp; Evolution\u003c/em\u003e, 2017, 1: 1828-1835.\u003c/li\u003e\n\u003cli\u003eLi H, Wang L, Peng Y, et al. Film mulching, residue retention and N fertilization affect ammonia volatilization through soil labile N and C pools. \u003cem\u003eAgriculture, Ecosystems \u0026amp; Environment\u003c/em\u003e, 2021, 308: 107272.\u003c/li\u003e\n\u003cli\u003eLiang Y, Al-Kaisi M, Yuan J, et al. Effect of chemical fertilizer and straw-derived organic amendments on continuous maize yield, soil carbon sequestration and soil quality in a Chinese Mollisol. \u003cem\u003eAgriculture, Ecosystems \u0026amp; Environment\u003c/em\u003e, 2021, 314: 107403.\u003c/li\u003e\n\u003cli\u003eLiu C, Lu M, Cui J, et al. Effects of straw carbon input on carbon dynamics in agricultural soils: a meta‐analysis. \u003cem\u003eGlobal Change Biology\u003c/em\u003e, 2014, 20: 1366-1381.\u003c/li\u003e\n\u003cli\u003eLiu Z, Zhao C, Zhang P, et al. Long-term effects of plastic mulching on soil structure, organic carbon and yield of rainfed maize. \u003cem\u003eAgricultural Water Management\u003c/em\u003e, 2023, 287: 108447.\u003c/li\u003e\n\u003cli\u003eLu J, Tian H, Xiong J, et al. Effects of N and P fertilization on soil N-cycling microbial community structure in white clover grasslands. \u003cem\u003eCurrent Microbiology\u003c/em\u003e, 2025, 82: 1-14.\u003c/li\u003e\n\u003cli\u003eMa D, Chen L, Qu H, et al. Impacts of plastic film mulching on crop yields, soil water, nitrate, and organic carbon in Northwestern China: A meta-analysis. \u003cem\u003eAgricultural Water Management\u003c/em\u003e, 2018, 202: 166-173.\u003c/li\u003e\n\u003cli\u003eMa S, Cao Y, Lu J, et al. Response of soil aggregation and associated organic carbon to organic amendment and its controls: A global meta-analysis. \u003cem\u003eCatena\u003c/em\u003e, 2024, 237: 107774.\u003c/li\u003e\n\u003cli\u003eMary B, Recous S, Darwis D, et al. Interactions between decomposition of plant residues and nitrogen cycling in soil. \u003cem\u003ePlant and Soil\u003c/em\u003e, 1996, 181: 71-82.\u003c/li\u003e\n\u003cli\u003eMeng X, Zhang X, Li Y, et al. Nitrogen fertilizer builds soil organic carbon under straw return mainly via microbial necromass formation. \u003cem\u003eSoil Biology and Biochemistry\u003c/em\u003e, 2024, 188: 109223.\u003c/li\u003e\n\u003cli\u003eNdzelu B S, Dou S, Zhang X, et al. Tillage effects on humus composition and humic acid structural characteristics in soil aggregate-size fractions. \u003cem\u003eSoil and Tillage Research\u003c/em\u003e, 2021, 213: 105090.\u003c/li\u003e\n\u003cli\u003eParr M, Grossman J M, Reberg‐Horton S C, et al. Nitrogen delivery from legume cover crops in no‐till organic corn production. \u003cem\u003eAgronomy Journal\u003c/em\u003e, 2011, 103: 1578-1590.\u003c/li\u003e\n\u003cli\u003ePietri J C A, Brookes P C. Substrate inputs and pH as factors controlling microbial biomass, activity and community structure in an arable soil. \u003cem\u003eSoil Biology and Biochemistry\u003c/em\u003e, 2009, 41: 1396-1405.\u003c/li\u003e\n\u003cli\u003eRam H, Dadhwal V, Vashist K K, et al. Grain yield and water use efficiency of wheat (\u003cem\u003eTriticum aestivum\u003c/em\u003e L.) in relation to irrigation levels and rice straw mulching in North West India. \u003cem\u003eAgricultural Water Management\u003c/em\u003e, 2013, 128: 92-101.\u003c/li\u003e\n\u003cli\u003eSemenov V M, Tulina A S, Semenova N A, et al. Humification and nonhumification pathways of the organic matter stabilization in soil: A review. \u003cem\u003eEurasian Soil Science\u003c/em\u003e, 2013, 46: 355-368.\u003c/li\u003e\n\u003cli\u003eSix J, Bossuyt H, Degryze S, et al. A history of research on the link between (micro) aggregates, soil biota, and soil organic matter dynamics. \u003cem\u003eSoil and Tillage Research\u003c/em\u003e, 2004, 79: 7-31.\u003c/li\u003e\n\u003cli\u003eSteinmetz Z, Wollmann C, Schaefer M, et al. Plastic mulching in agriculture. Trading short-term agronomic benefits for long-term soil degradation? \u003cem\u003eScience of the Total Environment\u003c/em\u003e, 2016, 550: 690-705.\u003c/li\u003e\n\u003cli\u003eSui X, Bao X, Xie H, et al. Contrasting seasonal effects of legume and grass cover crops as living mulch on the soil microbial community and nutrient metabolic limitations. \u003cem\u003eAgriculture, Ecosystems \u0026amp; Environment\u003c/em\u003e, 2025, 380: 109374.\u003c/li\u003e\n\u003cli\u003eTejada M, Ben\u0026iacute;tez C. Effects of crushed maize straw residues on soil biological properties and soil restoration. \u003cem\u003eLand Degradation \u0026amp; Development\u003c/em\u003e, 2014, 25: 501-509.\u003c/li\u003e\n\u003cli\u003eVerchot L V, Dutaur L, Shepherd K D, et al. Organic matter stabilization in soil aggregates: understanding the biogeochemical mechanisms that determine the fate of carbon inputs in soils. \u003cem\u003eGeoderma\u003c/em\u003e, 2011, 161: 182-193.\u003c/li\u003e\n\u003cli\u003eWang J, Fu X, Sainju U M, et al. Soil carbon fractions in response to straw mulching in the Loess Plateau of China. \u003cem\u003eBiology and Fertility of Soils\u003c/em\u003e, 2018, 54: 423-436.\u003c/li\u003e\n\u003cli\u003eWang M, Liu Z, Zhai B, et al. Long-term straw mulch underpins crop yield and improves soil quality more efficiently than plastic mulch in different maize and wheat systems. \u003cem\u003eField Crops Research\u003c/em\u003e, 2023, 300: 109003.\u003c/li\u003e\n\u003cli\u003eWang Y, Liu L, Tian Y, et al. Temporal and spatial variation of soil microorganisms and nutrient under white clover cover. \u003cem\u003eSoil and Tillage Research\u003c/em\u003e, 2020, 202: 104666.\u003c/li\u003e\n\u003cli\u003eWhitman T, Pepe-Ranney C, Enders A, et al. Dynamics of microbial community composition and soil organic carbon mineralization in soil following addition of pyrogenic and fresh organic matter. \u003cem\u003eThe ISME Journal\u003c/em\u003e, 2016, 10: 2918-2930.\u003c/li\u003e\n\u003cli\u003eWu L, Zhang W, Wei W, et al. Soil organic matter priming and carbon balance after straw addition is regulated by long-term fertilization. \u003cem\u003eSoil Biology and Biochemistry\u003c/em\u003e, 2019, 135: 383-391.\u003c/li\u003e\n\u003cli\u003eXue B, Huang L, Huang Y, et al. Straw management influences the stabilization of organic carbon by Fe (oxyhydr)oxides in soil aggregates. \u003cem\u003eGeoderma\u003c/em\u003e, 2020, 358: 113987.\u003c/li\u003e\n\u003cli\u003eYang H, Fang C, Meng Y, et al. Long-term ditch-buried straw return increases functionality of soil microbial communities. \u003cem\u003eCatena\u003c/em\u003e, 2021, 202: 105316.\u003c/li\u003e\n\u003cli\u003eYang Y, Yu K, Feng H. Effects of straw mulching and plastic film mulching on improving soil organic carbon and nitrogen fractions, crop yield and water use efficiency in the Loess Plateau, China. \u003cem\u003eAgricultural Water Management\u003c/em\u003e, 2018, 201: 133-143.\u003c/li\u003e\n\u003cli\u003eYu Y, Zhang Y, Xiao M, et al. A meta-analysis of film mulching cultivation effects on soil organic carbon and soil greenhouse gas fluxes. \u003cem\u003eCatena\u003c/em\u003e, 2021, 206: 105483.\u003c/li\u003e\n\u003cli\u003eZeng F, Chen S, Miao Y, et al. Changes of organic acid exudation and rhizosphere pH in rice plants under chromium stress. \u003cem\u003eEnvironmental Pollution\u003c/em\u003e, 2008, 155: 284-289.\u003c/li\u003e\n\u003cli\u003eZhang P, Wei T, Li Y, et al. Effects of straw incorporation on the stratification of the soil organic C, total N and C:N ratio in a semiarid region of China. \u003cem\u003eSoil and Tillage Research\u003c/em\u003e, 2015, 153: 28-35.\u003c/li\u003e\n\u003cli\u003eZhang S, L\u0026ouml;vdahl L, Grip H, et al. Effects of mulching and catch cropping on soil temperature, soil moisture and wheat yield on the Loess Plateau of China. \u003cem\u003eSoil and Tillage Research\u003c/em\u003e, 2009, 102: 78-86.\u003c/li\u003e\n\u003cli\u003eZhang S, Zheng Q, Noll L, et al. Environmental effects on soil microbial nitrogen use efficiency are controlled by allocation of organic nitrogen to microbial growth and regulate gross N mineralization. \u003cem\u003eSoil Biology and Biochemistry\u003c/em\u003e, 2019, 135: 304-315.\u003c/li\u003e\n\u003cli\u003eZhao X, Liu B Y, Liu S L, et al. Sustaining crop production in China\u0026apos;s cropland by crop residue retention: A meta‐analysis. \u003cem\u003eLand Degradation \u0026amp; Development\u003c/em\u003e, 2020, 31: 694-709.\u003c/li\u003e\n\u003cli\u003eZhao Z, Wang P, Xiong X, et al. Environmental risk of multi-year polythene film mulching and its green solution in arid irrigation region. \u003cem\u003eJournal of Hazardous Materials\u003c/em\u003e, 2022, 435: 128981.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"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":"Arid irrigation region, Embedded biomass mulching, Polythene film mulching, Soil structure, Soil physicochemical properties, Water productivity","lastPublishedDoi":"10.21203/rs.3.rs-7471631/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7471631/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground and Aims\u003c/h2\u003e\u003cp\u003ePolyethylene film mulching is common in dryland agriculture but may degrade soil functions and environmental quality over time. This study aimed to assess biomass‑based mulching as a sustainable alternative that maintains crop yield while reducing plastic pollution in arid regions.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e\u003cp\u003eThis two‑year field experiment in an arid irrigated region examined soil physicochemical properties, soil enzyme activities, and maize yield under six mulching treatments: shallow‑incorporated dried maize straw (SM), living clover embedding (CM), biomass beneath plastic film (PM\u0026thinsp;+\u0026thinsp;SM and PM\u0026thinsp;+\u0026thinsp;CM), sole plastic film (PM), and bare land control (CK).\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eCompared with CK and PM, SM and PM\u0026thinsp;+\u0026thinsp;SM greatly reduced soil bulk density and pH, and increased macroaggregates proportion and geometric mean diameter. Both treatments also enhanced organic carbon and labile carbon contents by 17.7%-21.1% and 27.7%-31.8% compared with PM. CM and PM\u0026thinsp;+\u0026thinsp;CM were most effective in promoting nitrogen cycling, increasing total, organic, and inorganic nitrogen by 4.19%, 18.18%, and 4.65%, respectively, relative to CK. PM\u0026thinsp;+\u0026thinsp;SM and PM\u0026thinsp;+\u0026thinsp;CM also resulted in higher microbial biomass and urease and β-glucosidase activities than PM alone. Structural equation modeling further confirmed that the embedded biomass mulching enhanced soil functions and crop yields.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e\u003cp\u003eWhile combining biomass with plastic film can maximize agronomic outcomes, sole biomass mulching offers comparable improvements in soil quality and yield without the environmental risks of plastic film. Biomass embedding thus represents a nature‑based, sustainable strategy to advance agricultural productivity and soil health in arid regions.\u003c/p\u003e","manuscriptTitle":"Embedded biomass into topsoil as a green production mode to ensure soil structure and functions in arid irrigation region","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-09-16 08:52:05","doi":"10.21203/rs.3.rs-7471631/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":"330c3d17-bb04-43bc-9868-cc33124ce7a1","owner":[],"postedDate":"September 16th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-10-21T01:32:15+00:00","versionOfRecord":[],"versionCreatedAt":"2025-09-16 08:52:05","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7471631","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7471631","identity":"rs-7471631","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}