Gladis Zinati , Joseph E. Carrara , Saurav Das , Romans Caetani , Amiya Kalra , Eric A. Carr , Wade P. Heller
{"title":"Impact of tillage practices and arbuscular mycorrhizal fungi inoculation on organic sweet corn yield and nutritional quality","authors":"Gladis Zinati , Joseph E. Carrara , Saurav Das , Romans Caetani , Amiya Kalra , Eric A. Carr , Wade P. Heller","doi":"10.1016/j.still.2025.106545","DOIUrl":"10.1016/j.still.2025.106545","url":null,"abstract":"<div><div>The application of mycorrhizal biofertilizers in agriculture has demonstrated potential for improving crop yield and nutrition. However, their effectiveness across different tillage systems and under on-farm conditions remain underexplored. This two-year study evaluated the effects of tillage practices and supplemental arbuscular mycorrhizal fungi (AMF) inoculation on the yield and nutrient composition of organically grown sweet corn (<em>Zea mays</em>). The experiment followed a split-plot design with two tillage practices—full tillage (FT) and reduced tillage (RT)—and four AMF treatments: mock (control), native AMF community (NAT), <em>Rhizophagus irregularis</em>, and <em>Funneliformis mosseae</em>. Results showed that FT significantly increased fresh and dry ear yields compared to RT. AMF inoculation, particularly with <em>R. irregularis</em>, enhanced kernel phosphorus (P) and potassium (K) concentrations. Inoculation with <em>R. irregularis</em> and <em>F. mosseae</em> also increased kernel vitamin B6 and C levels. Tillage influenced amino acid composition, with leucine and phenylalanine concentrations being higher in FT, while tryptophan was greater in RT. Additionally, <em>R. irregularis</em> and <em>F. mosseae</em> inoculation increased aspartic acid and glycine concentrations, which play a role in scavenging reactive oxygen species (ROS), suggesting a potential role for AMF in enhancing crop stress resilience and nutritional quality. Despite these benefits, natural AMF colonization across treatments may have masked the full effects of supplemental inoculation, highlighting the complexity of evaluating AMF biofertilizers in field conditions. Overall, this study suggests that while the presence of native AMF complicates the assessment of exogenous inoculation, AMF biofertilizers have positive implications for enhancing nutrient density of sweet corn across tillage practices.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"251 ","pages":"Article 106545"},"PeriodicalIF":6.1,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143610818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jian Zhang , Peikun Li , Lin Li , Mina Zhao , Peisen Yan , Yuan Liu , Wei Li , Shengyan Ding , Qinghe Zhao
{"title":"Soil respiration and carbon sequestration response to short-term fertilization in wheat-maize cropping system in the North China Plain","authors":"Jian Zhang , Peikun Li , Lin Li , Mina Zhao , Peisen Yan , Yuan Liu , Wei Li , Shengyan Ding , Qinghe Zhao","doi":"10.1016/j.still.2025.106536","DOIUrl":"10.1016/j.still.2025.106536","url":null,"abstract":"<div><div>Fertilization significantly influences the soil physicochemical properties and crop growth in agricultural ecosystems, yet our understanding of its impact on soil respiration remains limited. To bridge this knowledge gap, we conducted a comprehensive study in the winter wheat-summer maize rotation system of the North China Plain. We examined the driving factors and processes governing soil respiration, and its temperature sensitivity (Q<sub>10</sub>), in response to various fertilization treatments, including an unfertilized control (CK), organic fertilizer (OM), organic fertilizer in combination with mineral fertilizer (OMNPK), and mineral fertilizer (NPK). Our findings revealed significant changes in Q<sub>10</sub> values under different treatments. In maize, Q<sub>10</sub> values increased by 4.4 % in OM, 19.9 % in OMNPK, and 15.5 % in NPK treatments. Conversely, in wheat, Q<sub>10</sub> values decreased by 9.9 %, 9.6 %, and 7.7 % under OM, OMNPK, and NPK treatments, respectively. Fertilization led to a substantial increase in mean soil respiration of both maize (6.6 %-12.7 %) and wheat (10.1 %-21.3 %). Moreover, fertilization significantly enhanced crop yield, stem biomass, and root biomass. In maize, soil respiration exhibited a linear increase with rising soil pH value, ammonium nitrogen and available potassium content, and crop biomass. Similarly, wheat soil respiration showed a linear trend with increasing soil pH value, total phosphorus, and soil organic carbon content. Structural equation modeling highlighted key factors contributing to variations in soil respiration. For maize, available potassium content, soil temperature, soil water content, and crop height explained 89 % of the variation. In wheat, pH value, total phosphorus, and total potassium content, soil temperature, soil water content, crop height, and crop biomass collectively accounted for 93 % of the variation of soil respiration. Fertilizer application significantly enhanced crop yield and carbon emission efficiency, specifically in wheat. Fertilized plots exhibited carbon emission efficiency 0.78–2.06 times higher than unfertilized plots in wheat. Among all treatments, OMNPK treatment maintained high yield, carbon emission efficiency, and net carbon sequestration in wheat. In summary, during winter wheat cultivation in the North China Plain, the practice of organic fertilizer combined with mineral fertilizer emerges as a superior strategy. This approach not only sustains crop yields but also augments carbon sequestration in crops, demonstrating its significant potential for agricultural carbon management.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"251 ","pages":"Article 106536"},"PeriodicalIF":6.1,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143610805","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}
Xu Yang , Jun Yuan , Yinghui Bi , Lidan Wang , Junqi Zhang , Chaoqun Wei , Xin Cui , Han Li , Peiyu Luo , Jun Meng , Wenfu Chen
{"title":"Assessing the methane mitigation potential of biochar and stover incorporation: Insights from the emission dynamics and soil microbiome in maize agroecosystems","authors":"Xu Yang , Jun Yuan , Yinghui Bi , Lidan Wang , Junqi Zhang , Chaoqun Wei , Xin Cui , Han Li , Peiyu Luo , Jun Meng , Wenfu Chen","doi":"10.1016/j.still.2025.106554","DOIUrl":"10.1016/j.still.2025.106554","url":null,"abstract":"<div><div>Methane (CH<sub>4</sub>), a significant greenhouse gas, plays a critical role in the global emission dynamics, with agricultural soils exerting dual action on its atmospheric levels. While the efficacy of biochar and stover incorporation in mitigating CH<sub>4</sub> emissions in flooded soils is well-documented, their impact in upland systems, particularly within maize monocropping systems, has not been fully elucidated. This study presents a comprehensive analysis of the effects of biochar and stover incorporation on CH<sub>4</sub> fluxes and the associated methanogenic and methanotrophic microbial communities in a maize monocropping system in Northeast China, over a five-year period. The field study was established with three treatments: untreated control (CK), maize stover incorporation at 7.5 t ha<sup>−1</sup> yr<sup>−1</sup> (MS), and biochar application at 2.63 t ha<sup>−1</sup> yr<sup>−1</sup> (MB). Soil CH<sub>4</sub> fluxes, physical and chemical properties, and abundances of <em>mcrA</em> and <em>pmoA</em> genes were measured. Our findings indicated that MB and MS treatments effectively enhanced total CH<sub>4</sub> uptakes during the study period compared to CK by 55.3 % and 84.4 %, respectively. Both MS and MB treatments significantly increased soil organic C (SOC), easily oxidizable C (EOC), and dissolved organic C (DOC) contents, with MS demonstrating a more pronounced boost. A shift in the microbial community, favoring methanotrophy, was indicated by a reduced <em>mcrA</em>/<em>pmoA</em> ratio and altered gene abundances of <em>mcrA</em> and <em>pmoA</em> in the MB and MS relative to the CK. Pearson’s correlation analysis did not find a significant relationship between DOC and soil water content (SWC) with CH<sub>4</sub> emissions. The random forest (RF) model identified that <em>pmoA</em>, <em>mcrA</em>/<em>pmoA,</em> SOC, and <em>mcrA</em> were the top four determinants of CH<sub>4</sub> emissions. This study underscores the potential of biochar and stover return as effective strategies for reducing agricultural CH<sub>4</sub> emissions and emphasizes the necessity of elucidating the microbial underpinnings involved. Further research is warranted to refine these practices for diverse agricultural contexts and to evaluate their long-term environmental efficacy.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"251 ","pages":"Article 106554"},"PeriodicalIF":6.1,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143610816","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}
Fangdi Chang , Hongyuan Zhang , Peiyi Zhao , Na Zhao , Jiashen Song , Ru Yu , Jing Wang , Xiquan Wang , Dongxun Han , Xiaodong Liu , Jie Zhou , Yuyi Li
{"title":"Green manure roots return drives saline-alkali soil organic carbon accumulation via microbial necromass formation","authors":"Fangdi Chang , Hongyuan Zhang , Peiyi Zhao , Na Zhao , Jiashen Song , Ru Yu , Jing Wang , Xiquan Wang , Dongxun Han , Xiaodong Liu , Jie Zhou , Yuyi Li","doi":"10.1016/j.still.2025.106550","DOIUrl":"10.1016/j.still.2025.106550","url":null,"abstract":"<div><div>Green manure strongly affects saline-alkali soil organic carbon (SOC) sequestration. The mechanism by which green manure influences the contribution of plant and microbial-derived carbon (C) to SOC in wheat-green manure cropping system remains unclear. Herein, plant residue C (PRC), microbial, bacterial, and fungal necromass C (MNC, BNC, and FNC), enzyme activity and microbial community were determined under wheat fallow after harvest (CK), green manure roots return (GMR), and green manure shoots and roots return (GMRS) in a five-year field experiment. Compared with CK, GMR and GMRS increased SOC content by 12 % and 11 % at 0–20 cm, respectively. Specifically, GMR accelerated the lignin biotransformation by increasing the relative abundance of <em>K</em>-strategy fungi, caused a reduction in the contribution of plant residues to SOC by 16–31 %. While GMR increased MNC, especially BNC by 1.6–2.8 times, which was the primary driver of SOC sequestration. Comparatively, GMRS increased the relative abundance of <em>r</em>-strategy bacteria by 12–13 %, and C- and N-acquisition enzymes by 12–17 % and 56–68 % compare to CK. This in turn, increased the accumulation of PRC, but decreased MNC (especially FNC) contribution to SOC. Overall, green manure return strategies altered the contribution of plant residues and microbial necromass to SOC by regulating microbial life strategies. MNC (especially FNC) contributed more to SOC than PRC. Therefore, green manure specially root return is a viable option to drive SOC accumulation via microbial necromass formation in wheat-green manure cropping system in saline-alkali soils.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"251 ","pages":"Article 106550"},"PeriodicalIF":6.1,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143610819","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}
Lucas Raimundo Bento , João Vitor dos Santos , Steffen A. Schweizer , Carla Pereira de Morais , Milene Corso Mitsuyuki , Patrícia Perondi Anchão Oliveira , José Ricardo Macedo Pezzopane , Alberto Carlos de Campos Bernardi , Ladislau Martin-Neto
{"title":"Moderate pasture intensification enhances soil organic carbon stocks in a degraded Brazilian Ferralsol","authors":"Lucas Raimundo Bento , João Vitor dos Santos , Steffen A. Schweizer , Carla Pereira de Morais , Milene Corso Mitsuyuki , Patrícia Perondi Anchão Oliveira , José Ricardo Macedo Pezzopane , Alberto Carlos de Campos Bernardi , Ladislau Martin-Neto","doi":"10.1016/j.still.2025.106534","DOIUrl":"10.1016/j.still.2025.106534","url":null,"abstract":"<div><div>Sustainable intensification presents a unique opportunity to enhance carbon stocks in degraded pastures by optimizing forage production and consumption, thereby increasing soil organic matter (SOM) inputs. This study aimed to (i) compare soil carbon stocks to a depth of 1 m across various intensively managed pastures subjected to nitrogen fertilization, adjustments in animal stocking rates, and rotational grazing on a previously degraded pasture (DP) in a long-term field experiment in Brazilian Ferralsols; and (ii) evaluate changes in SOM composition. We compared irrigated pastures with a high animal stocking rate (IHS), a rainfed pasture with a high animal stocking rate (RHS), and a rainfed pasture with a moderate animal stocking rate (RMS) to improve DP. The origin of SOM was assessed using the natural abundance of <sup>13</sup>C and its composition through the H/C atomic ratio and the aromaticity index (H<sub>LIFS</sub>) obtained by laser-induced fluorescence spectroscopy. A comparison between the degraded pasture and the adjacent native vegetation showed that unmanaged pasture reduced carbon stocks by 45 Mg C ha<sup>−1</sup>. However, intensification in degraded pasture enhanced the organic carbon stocks from 102 to 139 Mg C ha<sup>−1</sup> for RHS and 162 Mg C ha<sup>−1</sup> for RMS in the top 1 m. These values were comparable to those of the adjacent native forest (148 Mg C ha<sup>−1</sup>). In contrast, high intensification in IHS with irrigation and high nitrogen fertilization did not increase organic carbon stocks compared to unmanaged DP, which remained at 111 Mg C ha<sup>−1</sup>. Both RHS and RMS promoted the accumulation of aliphatic compounds, as evidenced by the high H/C atomic ratio and low H<sub>LIFS</sub> index. When comparing RHS and RMS, we observed that a moderate animal stocking rate resulted in a greater accumulation of pasture-derived carbon (52 Mg C ha<sup>−1</sup>) than a high animal stocking rate (37 Mg C ha<sup>−1</sup>) in the top 30 cm. This difference is likely due to faster pasture regrowth under moderate stocking rates, leading to increased incorporation of pasture-derived SOM. Overall, moderate pasture intensification promoted carbon sequestration (2 Mg C ha<sup>−1</sup> year<sup>−1</sup>) compared to DP by introducing carbon derived from forage, reducing nitrogen fertilizer use, and preserving carbon from native vegetation.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"251 ","pages":"Article 106534"},"PeriodicalIF":6.1,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143591904","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}
Ahmed S. Elrys , Jinbo Zhang , Lei Meng , Pierfrancesco Nardi , Christoph Müller
{"title":"Clay-to-carbon ratio: An overlooked but pivotal mediator of soil nitrogen mineralization and availability","authors":"Ahmed S. Elrys , Jinbo Zhang , Lei Meng , Pierfrancesco Nardi , Christoph Müller","doi":"10.1016/j.still.2025.106533","DOIUrl":"10.1016/j.still.2025.106533","url":null,"abstract":"<div><div>The supply of nitrogen (N) to plants depends largely on soil organic matter content, but clay has a stabilizing effect on organic matter, protecting it from microbial attack, which may ultimately affect soil N mineralization rate. The clay-to-carbon ratio has recently been selected as an indicator of soil organic matter status. However, whether the clay-to-carbon ratio is relevant for assessing soil gross N mineralization rate (GNM) remains uncertain. By analyzing 1851 observations from 420 <sup>15</sup>N-labelled studies, we found a significant and negative relationship between the clay-to-carbon ratio and both GNM and NH<sub>4</sub><sup>+</sup>-N concentration globally and across soil layers, land uses and climatic regions. Decreased clay-to-carbon ratio accelerated GNM via increasing soil microbial biomass, total N, and fungal abundance. The effect of soil pH, aridity and temperature on GNM is mediated through the clay-to-carbon ratio. Higher soil pH, aridity and temperature inhibited GNM by increasing the clay-to-carbon ratio. Thus, the higher the clay content, the more organic matter is required to ensure a high N supply to plants, especially in arid soils with high pH. Overall, incorporating the clay-to-carbon ratio into next-generation conceptual models as a pivotal mediator of GNM improves predictions of soil N supply globally.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"251 ","pages":"Article 106533"},"PeriodicalIF":6.1,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143591905","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}
Yunru Lai , Jonathan J. Ojeda , Simon Clarendon , Nathan Robinson , Enli Wang , Keith G. Pembleton
{"title":"Linking measurable and conceptual phosphorus pools (in APSIM) enables quantitative model initialisation","authors":"Yunru Lai , Jonathan J. Ojeda , Simon Clarendon , Nathan Robinson , Enli Wang , Keith G. Pembleton","doi":"10.1016/j.still.2025.106532","DOIUrl":"10.1016/j.still.2025.106532","url":null,"abstract":"<div><div>Phosphorus (P) is an essential plant macro-nutrient, yet it is deficient in 65 % of agricultural soils worldwide. Agricultural systems models enable the integration of plant-soil-climate-management interactions to investigate crop responses to P fertilisation and improve P use efficiency. However, current models cannot align their modellable P pools with values obtained from soil tests. This limits their applicability since soil testing is the most widely used tool to assess soil P status, which is then used to predict fertiliser P requirements based on assumed crop P demand for optimal growth in the field. Our study introduces a modelling framework akin to inversely modelling in the Agricultural Production Systems sIMulator (APSIM) to quantitatively derive the most likely P modelling parameters for different soils and empirically link them to common soil P test values. The methodology was first tested using data from an 8-year alfalfa (syn. lucerne) experiment (1997–2004) on two soil types in the mid-west of the United States to establish the adequacy of the P modelling framework in APSIM. We then extended this approach to eight Australian soil types using a simulation study based on known wheat yield response curves to soil P tests to derive empirical relationships between the labile P values in APSIM and common soil test P values (Bray-2 P and Colwell P) for the soils studied. Cross-validation yielded an average <em>R</em><sup>2</sup> of 0.98 and an average Lin’s Concordance Correlation Coefficient (CCC) of 0.92. Our work thus enables the initialisation of the labile P pool in APSIM using Bray-2 P and Colwell P data, enhancing the usability and accuracy of agricultural systems models in predicting crop P requirements and optimising P fertiliser use across diverse soil types in different agro-climatic regions.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"251 ","pages":"Article 106532"},"PeriodicalIF":6.1,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143591903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Predicting the spatial distribution of organic carbon in soil by combining machine learning algorithms and spline depth function in a part of Golestan Province, Iran","authors":"Maryam Emami , Farhad Khormali , Mohammad Reza Pahlavan-Rad , Soheila Ebrahimi","doi":"10.1016/j.still.2025.106530","DOIUrl":"10.1016/j.still.2025.106530","url":null,"abstract":"<div><div>As a critical element of soil quality, soil organic carbon (SOC) constitutes nearly 75 % of the active carbon content in terrestrial ecosystems and is essential for agricultural productivity. Estimation of soil organic carbon is one of the requirements of effective soil management planning. The present paper aimed to test the performance of Cubist (Cu), Quantile Regression Forest (QRF), and Random Forest (RF) methods in predicting the distribution of SOC content at four soil depths of 0–15, 15–30, 30–60 and 60–100 cm in Golestan Province of Iran. To achieve this goal, the mentioned models were trained with 105 soil profiles across the study area using environmental covariates which had been obtained from DEM, rain and piezometric maps, and remote sensing data extracted from Landsat 7 ETM<sup>+</sup>. Results revealed that the mean SOC values varied between 0.39 % and 1.24 %. All three predictive models had the highest performance in predicting SOC at 15–30 cm depth (R<sup>2</sup> = 0.45, RMSE = 0.34, and MAE = 0.25). Although the predictive models were similar in terms of validation metrics criteria (R<sup>2</sup>, RMSE, and MAE), the QRF predictions based on the Taylor diagram had a higher agreement with the measured SOC distribution, resulting in the identification of QRF as the leading model in performance. Results of the present paper indicate the high potential of rainfall, piezometric, MRVBF, MRRTF, and valley depth to predict SOC concentration distributions. These findings will contribute to further research on SOC prediction models.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"251 ","pages":"Article 106530"},"PeriodicalIF":6.1,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143591901","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}
Jingjing Zhang , Jiaqing Huang , Jiong Wen , Zhi Peng , Nan Zhang , Yanan Wang , Yang Zhang , Shiming Su , Xibai Zeng
{"title":"Phosphorus fractions and their transformation in coupling with organic carbon cycling after seven-year manure application in subtropical soil","authors":"Jingjing Zhang , Jiaqing Huang , Jiong Wen , Zhi Peng , Nan Zhang , Yanan Wang , Yang Zhang , Shiming Su , Xibai Zeng","doi":"10.1016/j.still.2025.106535","DOIUrl":"10.1016/j.still.2025.106535","url":null,"abstract":"<div><div>Phosphorus (P) is a crucial macronutrient for crop yield. Repeated swine manure application can provide considerable amounts of P and organic carbon (C) for agricultural soils. However, a deeper understanding of the transformation of soil P fractions and their coupling with organic C cycling through chemical and biological processes is urgently needed to enhance P utilization efficiency and C sequestration. A seven-year swine manure application (SSMA) experiment was conducted at varying rates (0, 7.5, 15, 30, and 45 t·ha<sup>−1</sup> per year) to investigate the changes in P fractions, the coupling of P and C transformation, and the driving factors in acidic soils. The results revealed that SSMA significantly increased soil total P, predominantly as inorganic P (P<sub>i</sub>), whereas organic P (P<sub>o</sub>) exhibited a limited increase and plateaued at 15 t·ha<sup>−1</sup> manure application. The 15–45 t·ha<sup>−1</sup> manure treatments dramatically enhanced the nonstable P fractions, particularly pH- and Ca-induced Ca<sub>8</sub>-P; moreover, Ca<sub>8</sub>-P had a greater impact on Olsen-P than Fe-P and Al-P. SSMA promoted P mobilization by increasing alkaline phosphatase activity and the abundance of P-cycling functional genes. However, the primary factors directly affecting nonstable P fractions were the elevated soil pH and soil organic carbon (SOC). Additionally, nonstable P fractions were positively correlated with O-aryl-C and ketone-C components. Swine manure applications altered organic C components by stimulating SOC-driven enzyme activities involved in organic C degradation. Organic C components were also influenced by available P and N, primarily through the abundance of genes involved in organic C fixation rather than C degradation. Furthermore, 45 t·ha<sup>−1</sup> SSMA treatment restricted the increase in the abundance of P-cycling genes, most C-cycling genes, and dominant bacteria harboring P-cycling genes. This study provides critical insights into the coupling transformation mechanisms of P and C and highlights that excessive swine manure application impairs functional bacterial growth and organic C storage in addition to increasing the risk of P loss in agricultural soils.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"251 ","pages":"Article 106535"},"PeriodicalIF":6.1,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143591902","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}
Le Yang , Zhihong Zhang , Baoping Yan , Shuo Yuan , Fu Zhang
{"title":"Design and evaluation of bio-inspired electro-osmosis system for reducing soil adhesion on agricultural equipment","authors":"Le Yang , Zhihong Zhang , Baoping Yan , Shuo Yuan , Fu Zhang","doi":"10.1016/j.still.2025.106521","DOIUrl":"10.1016/j.still.2025.106521","url":null,"abstract":"<div><div>Enhancing the efficiency of agricultural field operations is crucial, but soil adhesion to soil-engaging tools poses a major obstacle, causing energy waste and reduced productivity. This research investigates a novel solution inspired by the anti-adhesion properties of earthworms, aiming to reduce soil adherence to agricultural equipment using a bio-inspired electro-osmosis system. The study details the design, optimization, and experimental testing of this system. The initial phase involved single-factor experiments to investigate the correlation between soil moisture content and adhesion force. The effects of variables such as the ratio of positive to negative surface areas, operating voltage, and voltage waveform on soil adhesion were thoroughly examined. A central composite design was employed to set up an experimental model, and regression analysis was performed using Design-Expert software. Results indicated that soil adhesion force increases with rising soil moisture content. Optimal conditions for maximum adhesion reduction were found to be a 1:2 <em>area ratio</em> for positive and negative surfaces, 12 V operating voltage, and alternating current. The regression model showed a strong correlation (<em>R</em><sup><em>2</em></sup>=0.981) between predicted and experimental data, with response surface plots revealing significant interactions between operating variables and adhesion force. The practical application of the electro-osmosis system was evaluated through field tests using a bio-inspired shovel blade designed with optimized parameters. Field tests confirmed that the bio-inspired shovel blade reduced horizontal traction force by 6.55 % and reduced soil adhesion by 52.84 % compared to a conventional shovel blade. This study presents a novel approach to reducing soil adhesion on agricultural tools by developing a bio-inspired electro-osmosis system that effectively replicates earthworm surface structures and electro-osmosis properties. These findings have profound implications for improving the sustainability and efficiency of agricultural operations.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":"251 ","pages":"Article 106521"},"PeriodicalIF":6.1,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143547854","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}