{"title":"Exploring the role of intercrops in enhancing soil enzyme activities and nutrient cycling in maize cultivation: A four-year field study","authors":"Vladimír Smutny , Jiri Holatko , Jiri Kucerik , Lubomir Neudert , Tamara Dryslova , Oldrich Latal , Lenka Porcova , Antonin Kintl , Tivadar Baltazar , Martin Brtnicky","doi":"10.1016/j.still.2025.106728","DOIUrl":"10.1016/j.still.2025.106728","url":null,"abstract":"<div><div>Undersowing cash crops with intercrops offers significant benefits for soil health and crop production. In response to the growing interest in maize undersowing, a four-year field experiment was conducted to evaluate the effects of various undersown intercrops, including grasses, cereals, and legumes, on microbial transformation and mineralization activities as well as the balance of these processes in relation to nutrient uptake and availability for plants and soil microbes.</div><div>The study demonstrated that undersowing maize in strips had a positive effect on biological soil properties. The enhancement of soil enzyme activities involved in nutrient transformation varied depending on the soil properties and climatic conditions in each of monitored years (2020–2023), and the type of intercrop used. The most significant changes in nutrient fluxes in the topsoil, as evidenced by C, N, P, S mineralizing enzymes and their microbial nutrient acquisition ratios, were observed in plots undersown with phacelia, crimson clover and perennial ryegrass. These changes were closely linked to the presence of intercropped plants and were not observed in the control interrows of the maize pure stand.</div><div>Undersowing was associated with increased nitrogen acquisition ratios (indicating higher demand for mineral nitrogen), as well as elevated activities of nitrogen-transforming (urease) and carbon-transforming (dehydrogenase, β-glucosidase) enzymes. All undersown treatments also enhanced phosphorus- and sulphur-mineralizing activities, in contrast to the maize, which pure stand exhibited reduced activity related to these nutrients.</div><div>Despite these improvements in soil biological properties, the enhancement did not translate into increased maize biomass for silage or grain yield. Nonetheless, the study underscores the potential of maize undersowing with intercrops in strips to improve soil fertility and nutrient cycling, thereby contributing to the long-term sustainability of agricultural systems.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"254 ","pages":"Article 106728"},"PeriodicalIF":6.1,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144534236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Spatio-temporal variations of soil particle size distribution under wind erosion in a temperate grassland: A seven-year landscape scale revisited analysis","authors":"Yuxin Feng, Zhuodong Zhang, Zhuoli Zhou, Bo Chen, Ying Li, Xinyu Zou, Rui Xu, Shuran Gao","doi":"10.1016/j.still.2025.106735","DOIUrl":"10.1016/j.still.2025.106735","url":null,"abstract":"<div><div>The soil particle size distribution (PSD) is generally perceived as stable as its change by pedogenesis is slow, but it actually undergoes dynamic spatio-temporal changes under the influences of surface processes, especially wind erosion due to its strong sorting effect. In areas with active surface processes like the wind eroded area, PSD dynamically changes (PSDD) as a result of the aeolian erosion and deposition in complementary to the local pedogenesis. Such PSDD is of great importance for understanding soil quality and optimize soil management, however, it is neglected in existing studies. This study analyzed the spatial variability of PSDD and its main influencing factors at depths of 0–1 cm and 1–6 cm in the Xilingele grassland, a typical temperate grassland, using revisited sampling from 2014–2021. The results indicate that in 0–1 cm, the clay increased by 4.76 %, the silt decreased by 1.08 % and the sand decreased by 3.65 %. In 1–6 cm, the clay increased by 2.36 %, the silt increased by 0.18 % and the sand decreased by 1.85 %. Spatial autocorrelation of PSD was moderate in both years, but the spatial heterogeneity decreased from 2014–2021 as dedicated nugget to sill ratio and range. The spatial pattern of PSD showed little temporal variation, with clay content in the 0–1 cm of western steppe and cultivated land increasing more than in mountainous areas, and sand content decreasing more on windward slopes than on flatlands and leeward slopes. The decrease in land use intensity contributed to an increase in clay content in vegetation restoration areas. Wind erosion exhibited a weakening trend in the study area during 2014–2021, but some hot spot areas still experience severe erosion. The decrease in wind erosion is a key factor in the increase in clay content in the region, with land use management contributing to the wind erosion reduction.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"254 ","pages":"Article 106735"},"PeriodicalIF":6.1,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144522943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiaoxian Duan, Quanjiu Wang, Weiyi Mu, Changkun Ma, Kai Wei, Yan Sun, Xue Zhao
{"title":"Application of activated water irrigation technology: A sustainable way to improve soil fertility and crop adaptability in the sandy area of southern Xinjiang","authors":"Xiaoxian Duan, Quanjiu Wang, Weiyi Mu, Changkun Ma, Kai Wei, Yan Sun, Xue Zhao","doi":"10.1016/j.still.2025.106731","DOIUrl":"10.1016/j.still.2025.106731","url":null,"abstract":"<div><div>Activated water treatment technology, emerging as a green irrigation strategy for arid sandy soils, demonstrates critical potential in enhancing soil fertility and crop productivity in southern Xinjiang's desert-oasis ecosystems. This study conducted a two-year field experiment to systematically evaluate the impacts of four irrigation treatments: conventional non-activated water (CK), magnetoelectric activated water (MI), micro-nano oxygenated water (IO), and magnetoelectric-oxygenated water (MO). The investigation focused on their effects on root-zone soil moisture distribution patterns, nutrient availability and transformation efficiency, physiological growth indicator, and yield-water use synergies in apple orchards. The results indicate that activated water irrigation promotes soil nutrient absorption and conversion, improving soil fertility, with the soil quality index (SQI) increasing by 10.88 %–32.59 %. Under the conditions of soil salinization and the arid, water-scarce climate of southern Xinjiang, activated water irrigation enhances soil water retention, optimizes soil moisture distribution, and increases the effectiveness of soil moisture. Additionally, activated water irrigation effectively improves the drought resistance of apple trees, with CAT, POD, and SOD activities increasing by more than 10 %, and MDA reducing by up to 10.73 %. Apple yield increased by 12.11 %–35.48 %, and water use efficiency improved by 10.48 %–30.19 %. A synergistic effect was observed between MI and IO. This work establishes an integrated water activation framework for scientific irrigation scheduling in Xinjiang's desert-oasis farmlands and sustainable crop intensification in arid regions facing soil salinization and water scarcity.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"254 ","pages":"Article 106731"},"PeriodicalIF":6.1,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144522942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A data assimilation-based heat pulse method for monitoring soil hydraulic and thermal parameters in root zones","authors":"Xiaoting Xie , Lingzao Zeng , Tusheng Ren","doi":"10.1016/j.still.2025.106738","DOIUrl":"10.1016/j.still.2025.106738","url":null,"abstract":"<div><div>Continuous measurements of soil physical properties in root zones are crucial for understanding soil<img>plant interactions and sustainable agriculture. Traditional heat pulse (HP) methods are based on analytical solutions with the assumption of a homogeneous porous medium. The interpretation of HP signals obtained in soils with nonuniform soil thermal properties, such as HP measurements in root zones, is an ongoing problem. According to Bayes’ theorem, data assimilation methods can estimate model parameters and characterize their heterogeneity by integrating measurements with numerical models in a statistical manner. This paper introduces a novel data assimilation-based HP method that uses the iterative local updating ensemble smoother (ILUES) algorithm to solve this problem. The ILUES is implemented with three steps. First, generating a large volume of prior ensemble. Second, updating local ensembles of each sample with ensemble smoother to explore parameters distributions. Finally, inversion results of parameters to be estimated can be obtained by statistical analysis of these samples. It was evaluated theoretically on synthetic data and in practical applications, i.e., laboratory experiments in sandy soil with root fragments included. Then, the ILUES was further applied to infer the water content (θ) and bulk density (ρ<sub>b</sub>) in laboratory experiments. The results demonstrate significant improvements in the estimation accuracy for soil thermal properties, θ, and ρ<sub>b</sub>. Compared with those of the traditional method, the average values of the root mean square error (RMSE) decreased from 1.20 to 0.10 MJ m<sup>−3</sup> K<sup>−1</sup> for the volumetric heat capacity (<em>C</em>) estimates and from 0.4 to 0.3 W m<sup>−1</sup> K<sup>−1</sup> for the thermal conductivity (λ) estimates. Furthermore, the accuracies of the θ and ρ<sub>b</sub> values also improved significantly, with the RMSEs decreasing from 0.20 to 0.05 m<sup>3</sup> m<sup>-3</sup> and 0.60–0.10 g cm<sup>−3</sup>, respectively. This research provides a powerful tool for the in-situ monitoring of soil physical properties in root zones, providing deeper insights into soil<img>plant interactions and contributing to sustainable agricultural and environmental management practices.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"254 ","pages":"Article 106738"},"PeriodicalIF":6.1,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144522555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jinle Yu , Hongjun Chen , Miaomiao Wang , Jiachi Bao , Wenyi Song , Xitong He , Wenhai Shi
{"title":"A modified curve number method for runoff prediction of different vegetation types at the slope scale in China","authors":"Jinle Yu , Hongjun Chen , Miaomiao Wang , Jiachi Bao , Wenyi Song , Xitong He , Wenhai Shi","doi":"10.1016/j.still.2025.106737","DOIUrl":"10.1016/j.still.2025.106737","url":null,"abstract":"<div><div>The Soil Conservation Service Curve Number (SCS-CN) method is widely used to estimate surface runoff, relying on the Curve Number (<em>CN</em>) from the SCS handbook. However, its reliance on three discrete hydrologic condition (HC) categories (e.g., good, fair, poor) reduces sensitivity to land surface variability, leading to abrupt <em>CN</em> changes and inconsistent runoff estimates. To enhance <em>CN</em> estimation accuracy, this study assessed <em>CN</em> values for each HC using the median (CN <em>_</em>C) and least-squares fit (CN <em>_</em>F) methods based on rainfall-runoff observations from 65 monitoring sites across China. Although CN <em>_</em>F slightly improved CN estimation, it still resulted in unsatisfactory performance, with Nash–Sutcliffe efficiency (NSE) values below 60 % under many HC conditions, highlighting the limitations of categorical HC classification and internal <em>CN</em> variability. To address this, the study developed three equations integrating <em>CN</em> values with tabulated <em>CN</em> values for bare soil and vegetation coverage, tailored to grassland, shrubland, and woodland ecosystems. This method was calibrated and validated using data from 58 sites and tested at 7 independent sites. Results showed marked improvements in runoff prediction accuracy: for calibration, <em>NSE</em> values increased from 60.55 % (original method) to 78.57 % for grassland, from 58.51 % to 82.90 % for shrubland, and from –21.20–64.39 % for woodland. Similar improvements were observed in validation, with <em>NSE</em> increasing from 61.78 % to 79.11 % for grassland, 57.46–81.28 % for shrubland, and –43.68–62.71 % for woodland. These findings demonstrate the superior performance and broader applicability of the proposed method for runoff prediction in China’s diverse vegetated landscapes.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"254 ","pages":"Article 106737"},"PeriodicalIF":6.1,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144517170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mingtao Xiang , Xiaojia Chen , Songchao Chen , Chunyan Wu , Meiling Sheng , Zhouqiao Ren , Wanzhu Ma , Ming Ming , Xunfei Deng , Yu Zhan
{"title":"Spatiotemporal changes of soil organic carbon in intensive croplands over three decades: Emerging role of farmland utilization shifts","authors":"Mingtao Xiang , Xiaojia Chen , Songchao Chen , Chunyan Wu , Meiling Sheng , Zhouqiao Ren , Wanzhu Ma , Ming Ming , Xunfei Deng , Yu Zhan","doi":"10.1016/j.still.2025.106734","DOIUrl":"10.1016/j.still.2025.106734","url":null,"abstract":"<div><div>Understanding spatiotemporal variation characteristics and key driving factors of soil organic carbon (SOC) is crucial for refined managements of farmland quality and carbon emissions. Nevertheless, the impact of human-induced farmland utilization activities on regional SOC dynamics remains unclear. In this study, based on 1577 farmland topsoil (0–20 cm) samples, we developed a two-tiered stratification-contextualized framework within digital soil mapping paradigm for determining the drivers for spatiotemporal SOC dynamics by partitioning farmland and constructing individual machine learning method within farmland units (FUs) in East China during the 1980s-2010s, and then estimated spatiotemporal patterns of SOC as well as evaluated drivers on SOC changes within FUs using random forest models. Our results showed that the temporal changes in topsoil SOC stocks exhibited high spatial heterogeneity across three decades. The average SOC densities for the 1980s, 2000s, and 2010s were 41.4 ± 9.3 C ha<sup>−1</sup>, 47.4 ± 8.6 C ha<sup>−1</sup> and 39.7 ± 14.4 C ha<sup>−1</sup>, respectively, with SOC densities initially increasing and then decreasing in our intensively cultivated region. Climatic changes accounted for > 75 % of the relative importance (RI) to SOC dynamics over the past 30 years. Farmland utilization shifts accelerated temporal SOC changes, with the effects coefficient increasing from 2.6 % (95 % CI: 1.7∼3.1 %) to 6.4 % (95 % CI: 3.9∼7.4 %). Induced by farmland utilization shifts, the overall changes of SOC stock increased by 0.10 Mt C during the 1980s-2000s with minimal SOC changes in FU3 and parts of FU1 (only 1 %), while decreased by 0.33 Mt C during the 2000s-2010s with approximately 12.9 % of regions in FU3, FU5, FU1 and FU6 exhibiting changes over 3 %. This work enhanced the understanding of spatiotemporal SOC variability induced by farmland utilization using machine learning method based on determined FUs, which also provided valuable guidance for soil monitoring and carbon accounting management for intensively cultivated farmland.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"254 ","pages":"Article 106734"},"PeriodicalIF":6.1,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144517169","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xianfeng Zhang , Yiming Yun , Chaoyi Liu , Xiuli Xin , Wenliang Yang , Anning Zhu
{"title":"Conservation tillage exerts diverse pathways to sequester organic carbon in fluvo-aquic soils of the North China Plain","authors":"Xianfeng Zhang , Yiming Yun , Chaoyi Liu , Xiuli Xin , Wenliang Yang , Anning Zhu","doi":"10.1016/j.still.2025.106730","DOIUrl":"10.1016/j.still.2025.106730","url":null,"abstract":"<div><div>Conservation tillage (minimal tillage + straw return) significantly enhances soil organic carbon (SOC) accumulation, but the underlying pathways of C sequestration remain unclear. Using a 16-year conservation tillage experiment in the North China Plain, this study investigated how conservation tillage affects SOC quantity and lability, and identified the mechanisms by which tillage and straw management regulate SOC sequestration in the 0–10 cm surface layer. It was found that straw practice exerted a significantly stronger effect on the SOC pool than tillage regime. Compared to continuous tillage, reduced and no-tillage on average increased SOC by 0.55 g kg<sup>−1</sup> (with 12.6 % lower lability) under straw removal and by 0.63 g kg<sup>−1</sup> (with 15.3 % lower lability) under straw return. By contrast, across all tillage regimes, straw return significantly increased SOC concentration by 3.46–3.62 g kg<sup>−1</sup> and SOC lability by 34.9–40.8 % compared to straw removal. Reducing tillage frequency significantly decreased SOC mineralization, promoting the accumulation of relatively stable organic C through increased bulk density and inactive pore volume, along with decreased aeration and water-holding pore volumes. Whereas, straw return significantly increased organic C accumulation in physical subfractions, particularly fine intra-particulate organic matter and mineral-associated organic matter within macroaggregates, which predominantly accounted for the enhancements in SOC concentration and lability. Soil physicochemical properties differentially influenced microbial community abundance under conservation tillage. Specifically, bacteria responded positively to reduced and no-tillage, while both bacteria and fungi were stimulated by straw return, collectively stabilizing SOC. Reducing tillage frequency primarily increased bacterial necromass contribution to SOC, while straw return significantly enhanced necromass C derived from both bacteria and fungi. We conclude that conservation tillage enhances SOC sequestration through diverse pathways in the tested fluvo-aquic soils.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"254 ","pages":"Article 106730"},"PeriodicalIF":6.1,"publicationDate":"2025-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144481286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Mapping soil organic carbon sequestration potential in croplands using a combined proximal and remote sensing approach","authors":"Lulu Qi , Jiamin Ma , Qi Sun , Pu Shi","doi":"10.1016/j.still.2025.106733","DOIUrl":"10.1016/j.still.2025.106733","url":null,"abstract":"<div><div>Spatially explicit mapping of soil organic carbon (SOC) sequestration potential helps identify areas with the largest deficit for SOC accrual, but its implementation in a digital soil mapping (DSM) framework requires high-quality observational datasets that are often too resource-intensive to establish. The objective of this study was to develop an integrated proximal and remote sensing approach to efficiently map SOC sequestration potential in an agricultural region (25, 596 km<sup>2</sup>) of northeast China. Proximally sensed soil mid-infrared (MIR) spectra were used to develop memory-based local learning models that allowed accurate predictions of the mineral-associate organic carbon (MAOC) and clay+silt fractions (R<sup>2</sup>=0.97 and 0.98), which were then used to obtain point-based (n = 1158) estimates of SOC sequestration potential based on the C saturation concept. Using the training dataset augmented by spectral inference, a DSM model was built via random forest (RF) regression, with a collection of remote sensing derived environmental covariates as predictors. The performance of the RF model (R<sup>2</sup>=0.65, RMSE=1.42 kg/m<sup>2</sup>) represented a 30 % increase from the alternative with no addition of spectrally inferred data. The resultant map depicted a west-to-east increase in SOC sequestration potential, largely driven by the increasing capacity for C saturation. Shapley Additive exPlanation (SHAP) analysis revealed that the functional relationships between covariates and the target property were site-specific, but the climatic variables (mean annual precipitation (MAP) and mean annual temperature (MAT)) were on average the most important factors, followed by soil spectral indices that are related to soil texture and SOC. From a spatial perspective, the positive effect of MAP on SOC sequestration potential turned negative for areas with the highest MAP, due to erosion-induced topsoil loss that led to coarsening soil texture and thus diminishing capacity for SOC storage. This developed approach provided insights into the patterns and magnitude of SOC sequestration potential, serving as a basis for targeted cropland management and erosion control practices.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"254 ","pages":"Article 106733"},"PeriodicalIF":6.1,"publicationDate":"2025-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144491764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ying Xu , Yansheng Li , Zhenhua Yu , Jian Jin , Chunyu Zhang , Wenbin Bao , Xingyi Zhang , Guanghua Wang , Xiaobing Liu
{"title":"Roles of soil organic acids and base cations in Mollisol acidification during the peak growth stage of crops","authors":"Ying Xu , Yansheng Li , Zhenhua Yu , Jian Jin , Chunyu Zhang , Wenbin Bao , Xingyi Zhang , Guanghua Wang , Xiaobing Liu","doi":"10.1016/j.still.2025.106726","DOIUrl":"10.1016/j.still.2025.106726","url":null,"abstract":"<div><div>Changes in low-molecular-weight organic acids (LMWOAs), plant uptake or leaching of base cations (BCs) during peak crop growth affect soil acidity, particularly owing to excessive fertilizer use and intensive farming. The effect of LMWOAs and BCs on the acidity of Mollisol farmland is poorly understood. A long-term experiment with different fertilizer treatments under continuous cropping or corn–soybean rotation modules, was performed to examine the variation of LMWOAs and BCs during peak growth stages of corn and soybean and their effects on soil acidity. The LMWOAs concentrations ranged from 33.6 to 45.9 mg kg<sup>–1</sup> at the jointing stage of corn and 71.2–114 mg kg<sup>–1</sup> at the flowering stage of soybean. The predominant LMWOAs for corn are malic, acetic, and propanedioic acids, and malic, propanedioic, and succinic acids for soybean. Acetic acid was the main acidity determinant for corn (<em>r</em> = 0.714, <em>p</em> < 0.001), whereas that for soybean was malic acid (<em>r</em> = 0.704, <em>p</em> < 0.001). Acidification of the Mollisol farmland by LMWOAs and BCs during the peak crop growth stage is crop-specific and management-dependent. The higher total amount of LMWOAs may be one of the reasons for soil acidification in soybean. Continuous corn significantly increases the total LMWOAs concentration but reduces the content of BCs, exchangeable BCs (Ca<sup>2+</sup>, Mg<sup>2+</sup>, and Na<sup>+</sup>), whereas continuous soybean reduces no effect on either LMWOAs or BCs. Continuous corn cultivation, compared to rotational corn, reduces soil pH from 5.76 to 5.63, due to an increase in the total LMWOAs concentration, as well as a reduction in BCs and exchangeable BCs (Ca<sup>2+</sup>, Mg<sup>2+</sup>, and Na<sup>+</sup>) levels. There is no significant difference in soil pH between continuous and rotational soybean treatments but soil pH below 5.5 in both treatments. Rotation with chemical fertilizer for corn and dairy manure alone for soybean increases soil pH significantly owing to higher levels of BCs and exchangeable BCs (Ca<sup>2+</sup>, Mg<sup>2+</sup>, and K<sup>+</sup>). Manure application is more effective than straw return in mitigating soil acidity. Understanding the decomposition dynamics of LMWOAs during the crop cycle on soil acidity is required to lay a robust scientific basis for mitigating soil acidification in Mollisol farmlands.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"254 ","pages":"Article 106726"},"PeriodicalIF":6.1,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144481810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Loitongbam Joymati Chanu , Tapan Jyoti Purakayastha , Debarati Bhaduri , Muhammad Fraz Ali , Yashbir S. Shivay , Samapti Saren , Vikas Kumar , Majid Alhomrani , Abdulhakeem S. Alamri
{"title":"Assessment of soil biological quality under long-term rice-wheat cropping system: Effect of continuous vs. residual organic nutrient inputs","authors":"Loitongbam Joymati Chanu , Tapan Jyoti Purakayastha , Debarati Bhaduri , Muhammad Fraz Ali , Yashbir S. Shivay , Samapti Saren , Vikas Kumar , Majid Alhomrani , Abdulhakeem S. Alamri","doi":"10.1016/j.still.2025.106725","DOIUrl":"10.1016/j.still.2025.106725","url":null,"abstract":"<div><div>The goal of the study was to identify the key biological indicators of soil quality under multiyear of repeated organic manuring in either rice and residual effect in wheat (System I), wheat and residual effect in rice (System II) or both rice + wheat (System III) under subtropical climatic condition. The treatments were farmyard manure (FYM), <em>Sesbania</em> green manure (SGM), SGM with blue green algae (BGA), SGM+FYM, SGM+FYM+ BGA in rice; <em>Leucaena</em> green manure (LGLM), LGLM with <em>Azotobacter</em> (AZB), LGLM+FYM, LGLM+FYM+AZB in wheat. The soil samples were analyzed for soil biological properties such as basal respiration (BR), microbial biomass carbon (MBC), microbial metabolic quotient (MMQ), potential mineralizable nitrogen (PMN); and soil enzymatic activities <em>viz.</em> dehydrogenase (DHA), fluorescein diacetate (FDA) hydrolase, acid and alkaline phosphatases (AcPA and AlkPA), arylsulfatase (ArylSA) activities. Principal Component Analysis (PCA) identified key indicators <em>viz</em>. AcPA, MMQ, MBC (system I), FDA, and MMQ (system II); BR, DHA, MBC (system III). Fourteen years’ application of organics in system III enhanced the PMN (26 %, 43 %), FDA (31 %, 17 %), AlkPA (8 %, 9 %), AcPA (7 %, 11 %), ArylSA (36 %, 11 %) and REY (9 %, 12 %) over the system I and II, respectively. The treatment (SGM/LGLM+FYM+ BGA/AZB) in system III triggered the soil biological quality index (SBQI), and maximized the REY (rice equivalent yield). The study proved that the application of different combination of organic manures in rice, instead of wheat, may be recommended for improvement of both SBQI and productivity of rice-wheat system in semi-arid sub-tropical region of India. The identified biological indicators can be validated and used for indexing the SBQI for monitoring the time-to-time changes in soil biological health under the changing organic management system and this finding can be implemented in and around the Indo-Gangetic plain and in larger context to south and south-east Asia having similar soil type, environmental condition and cropping systems.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"254 ","pages":"Article 106725"},"PeriodicalIF":6.1,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144472207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}