Soil and Tillage Research最新文献

{"title":"Plastic film mulching with nitrogen application activates rhizosphere microbial nitrification and dissimilatory nitrate reduction in the Loess Plateau","authors":"Congwei Sun, Hui Wu, Subramaniam Gopalakrishnan, Enke Liu, Xurong Mei","doi":"10.1016/j.still.2024.106423","DOIUrl":"https://doi.org/10.1016/j.still.2024.106423","url":null,"abstract":"Plastic film mulching combined with nitrogen application is a prime chief strategy for enhancing maize yields in rain-fed agricultural areas. However, how the practice affects the productivity and functions of soil by altering nitrogen transformation mediated by rhizosphere microorganisms in the Loess Plateau, remains unclear. In this research, an 7-year field location experiment was conducted to ascertain the effects of plastic film mulching with nitrogen application (225 kg N ha<ce:sup loc=\"post\">−1</ce:sup>) on the rhizosphere microbial nitrogen transformation in a rain-fed maize field on the Loess Plateau. Plastic film mulching with nitrogen application reduced the pH value and also increased the abundance of microorganisms (e.g., <ce:italic>Nitrosospira</ce:italic>, <ce:italic>Halomonas</ce:italic>) and genes (e.g., <ce:italic>pmoB-amoB</ce:italic>, <ce:italic>hao</ce:italic>, <ce:italic>nirB</ce:italic>, and <ce:italic>nirD</ce:italic>) during the vegetative stage. This promoted nitrification and dissimilatory nitrate reduction to ammonium, which increased the content of inorganic nitrogen in the rhizosphere. During the reproductive stages, plastic flim mulching reduced the relative abundance of aerobic bacteria (e.g., <ce:italic>Skermanella</ce:italic>, <ce:italic>Sphingomonas</ce:italic>), and the ratio of (<ce:italic>nirK</ce:italic> + <ce:italic>nirS</ce:italic>) / <ce:italic>nosZ</ce:italic>, which inhibited denitrification and dinitrogen oxide emission potential. Overall, our findings highlight the feedback mechanism of soil nitrogen transformation to plastic film mulching with nitrogen application in the Loess Plateau, providing valuable insights for manipulating specific microorganisms to regulate nitrogen transformation and promoting the sustainability of soil ecosystems.","PeriodicalId":501007,"journal":{"name":"Soil and Tillage Research","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-leguminous green manures improve labile phosphorus availability and crop yield in agroecosystems: A global meta-analysis","authors":"Adnan Anwar Khan, Imran Azeem, Jing Hui, Yupei Chen, Yuqi Yuan, Tahir Shah, Muhammad Adeel, Noman Shakoor, Rana Muhammad Ammar Asghar, Weidong Cao, Dabin Zhang, Yajun Gao","doi":"10.1016/j.still.2024.106430","DOIUrl":"https://doi.org/10.1016/j.still.2024.106430","url":null,"abstract":"Incorporating the green manure (GM) approach in agroecosystems enhances phosphorus (P) availability and reduces mineral P-fertilizer input. Despite global promotion, a comprehensive global synthesis of the GM effect on soil P fractions is lacking. To address this gap, we conducted a meta-analysis of 48 published studies to evaluate the impact of climatic, edaphic, and agronomic variables on soil P fractions, enzyme activities, subsequent crop yield, and P uptake under a GM cropping system. Overall, GMs significantly increased the labile P fraction (n = 592) by 18 % compared with fallow management. Non-leguminous GMs showed a 21 % increase in labile P, resulting in an 18 % increase in subsequent crop yield and a 30 % increase in subsequent crop P uptake compared with fallow. Leguminous GMs stimulated soil enzyme activities, elevating acid phosphatase (ACP) by 40 % and β-glucosidase by 182 % compared with fallow. Compared to no-till (NT), GMs under conventional tillage (CT) significantly increased soil enzyme activities, including ACP, alkaline phosphatase (ALP), β-glucosidase, as well as subsequent crop yield, and P uptake. Long-term GM incorporation (5–10 yrs) significantly reduced moderately labile P by 25 %, leading to increased labile P fraction. Linear regression analysis demonstrated a positive correlation between labile P and soil organic carbon (SOC), but a negative with mean annual precipitation (MAP) and mean annual temperature (MAT). These findings suggest that incorporating GMs into a CT management system can potentially accelerate soil P cycling by promoting soil enzyme activities, enhancing subsequent crop production, and providing an alternative approach to reducing mineral P-fertilizer dependency. This approach exemplifies sustainable food production practices and underscores the significance of GMs for long-term agricultural resilience and soil health worldwide.","PeriodicalId":501007,"journal":{"name":"Soil and Tillage Research","volume":"65 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Space-time mapping of soil organic carbon through remote sensing and machine learning","authors":"Bruno dos Anjos Bartsch, Nicolas Augusto Rosin, Jorge Tadeu Fim Rosas, Raul Roberto Poppiel, Fernando Yutaro Makino, Letícia Guadagnin Vogel, Jean Jesus Macedo Novais, Renan Falcioni, Marcelo Rodrigo Alves, José A.M. Demattê","doi":"10.1016/j.still.2024.106428","DOIUrl":"https://doi.org/10.1016/j.still.2024.106428","url":null,"abstract":"Pedosphere is the largest terrestrial carbon reservoir. Soil organic carbon (SOC) is a critical attribute for soil quality and crop productivity, being directly linked to climate change mitigation and food security. Brazil boasts a significant agricultural production area and substantial potential for carbon sequestration. Nevertheless, the spatial-temporal distribution of SOC across the country is poorly understood, hindering the implementation of low-carbon agriculture public policies. We aimed to map the spatio-temporal distribution of SOC at from 0.00 to 0.20 cm depth over two periods. We assessed the SOC variation over seven years, generating a time series with five periods, obtaining the average SOC values. The Cubist algorithm was used to calibrate two short period (two years) and a long period (seven years/all period) models for SOC spatial prediction. Remote sensing data and soil particle size distribution maps were used as environmental covariates. We found in validation R<ce:sup loc=\"post\">2</ce:sup> values of 0.47 and 0.25 for short period models, and 0.34 for the long period model. The SOC content decreased by 54.97 % in the area according to the mapping by short period models and 53.72 % according to mapping by the long-period model. The predicted maps showed the same trend of the database (soil samples with observed SOC values) for the study areas using both short period and long period models.","PeriodicalId":501007,"journal":{"name":"Soil and Tillage Research","volume":"34 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How do different ant species mediate CH4 fluxes in slash-burn tropical forest soils?","authors":"Lingling Xie, Shaojun Wang, Mei Lu, Bo Xiao, Zhengjun Wang, Zhipeng Guo, Xiaofei Guo, Shuang Luo, Ru Li, Jiahui Xia, Shengqiu Yang, Mengjie Lan","doi":"10.1016/j.still.2024.106432","DOIUrl":"https://doi.org/10.1016/j.still.2024.106432","url":null,"abstract":"As important structuring force in ecosystems, ants play crucial roles in driving source-sink processes of soil methane (CH<ce:inf loc=\"post\">4</ce:inf>) through a series of biotic and abiotic pathways. However, there is still uncertainty about how different ant species regulate CH<ce:inf loc=\"post\">4</ce:inf> fluxes in slash-burn tropical soils. This study aimed to identify the pathways by which the different ant species (i.e., <ce:italic>Pheidole capellini</ce:italic>-honeydew harvester, <ce:italic>Odontoponera transversa</ce:italic>-predator, and <ce:italic>Pheidologeton affinis</ce:italic>-scavenger) control soil CH<ce:inf loc=\"post\">4</ce:inf> fluxes in Xishuangbanna tropical forests, southwestern China. We observed a net CH<ce:inf loc=\"post\">4</ce:inf> emission in the nests of three ant species (1.29 ± 0.047 μg m<ce:sup loc=\"post\">−2</ce:sup> h<ce:sup loc=\"post\">−1</ce:sup>) and a net uptake in the reference soils (-1.60 ± 0.043 μg m<ce:sup loc=\"post\">−2</ce:sup> h<ce:sup loc=\"post\">−1</ce:sup>). The contribution of three ant species to the reduction of annual total forest surface CH<ce:inf loc=\"post\">4</ce:inf> uptake ranged from 0.06 % to 4.82 %. The <ce:italic>P. capellini</ce:italic> nests increased CH<ce:inf loc=\"post\">4</ce:inf> emissions by 144.18 % compared with the reference soils, whereas <ce:italic>O. transversa</ce:italic> and <ce:italic>P. affinis</ce:italic> nests increased by 124.65 % and 111.71 %, respectively. In contrast with the reference soils, the greatest increase (33.7–511.1 %) in abundance of dominant methanogen taxa (Candidatus Thermoplasmatota and Euryarchaeota), methanogen Sobs index, soil water content, total organic carbon, and microbial biomass carbon was found in <ce:italic>P. capellini</ce:italic> nests. In contrast, the highest increase (92.0 %) in nitrate nitrogen was recorded in <ce:italic>P. affinis</ce:italic> nests. In particular, CH<ce:inf loc=\"post\">4</ce:inf> fluxes were directly or indirectly driven by increased Candidatus Thermoplasmatota abundance (26.04 %), soil water content (15.41 %), and microbial biomass carbon (11.70 %), while the abundance of Methylomirabilota bacteria explained 7.76 % of variation in CH<ce:inf loc=\"post\">4</ce:inf> fluxes. Our data indicate that CH<ce:inf loc=\"post\">4</ce:inf> fluxes vary with ant species probably due to their differentiated modification on methanogenic bacterial abundance, micro-habitat, and microbial carbon in Xishuangbann tropical soils. This results would provide further insight into the contribution of soil fauna to greenhouse gas emissions from tropical forests.","PeriodicalId":501007,"journal":{"name":"Soil and Tillage Research","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synergistic effects of bio-organic fertilizer and different soil amendments on salt reduction, soil fertility, and yield enhancement in salt-affected coastal soils","authors":"Meng Xiao, Shengguo Jiang, Jinbiao Li, Wenping Li, Pengxiao Fu, Guangming Liu, Jinlin Chen","doi":"10.1016/j.still.2024.106433","DOIUrl":"https://doi.org/10.1016/j.still.2024.106433","url":null,"abstract":"Soil salinization is associated with soil productivity and food stocks, and hazards to the sustainable development of agriculture economics and the ecological environment. Hence, to evaluate the improvement and underlying mechanisms of agricultural amelioration practices on salinity alleviation, soil fertility improvement and crop growth, the organic fertilizer and soil amendments were applied to the rice field in coastal saline soil over one year. In this study, five treatments replicated three times were conducted in 15 experimental plots including CK (no amendments addition), OF (bio-organic fertilizer addition), OH (bio-organic fertilizer combined with hydrolytic polymaleic anhydride addition), OQ (bio-organic fertilizer combined with carbon nano sol addition), OB (bio-organic fertilizer combined with potassium fulvic acid addition). Co-application of organic fertilizer and soil amendment significantly reduced soil pH and EC by 1.3 % - 3.7 % and 14 % - 20 %, respectively. Organic treatments OH has the highest content of SOC (10.46 g kg<ce:sup loc=\"post\">−1</ce:sup>) and available nitrogen (AN, 76 mg kg<ce:sup loc=\"post\">−1</ce:sup>). OB treatment has the highest content of available potassium (AK, 294 mg kg<ce:sup loc=\"post\">−1</ce:sup>), and the activity of soil urease (S-UE) and alkaline phosphatase (S-AKP). Organic treatments have significantly increased the plant height, leaf area, 1000-grain weight (4 %-7 %), and yield of rice (4 %-15 %) compared to CK. Organic fertilizer and amendments added explained 81 % and 68 % of the variation in SQI and rice yield, respectively. RDA analysis indicated that S-UE activity and nitrogen were the most factors that contributed to SQI and rice yield. Our results suggested that the organic fertilizer combined with soil amendments improved soil quality comprehensively, and enhanced rice growth and yield by reducing soil salt and salinity, and increasing soil biochemical properties (S-UE and N content) in coastal saline soil.","PeriodicalId":501007,"journal":{"name":"Soil and Tillage Research","volume":"34 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impacts of landscape factors on gully retreat and its morphological characteristics in hilly areas of Northeast China","authors":"Peng Jiao, Yang Ou, Shujiang Pang, Baixing Yan, Yu Zhang, Wenxu Xu, Liming Yan","doi":"10.1016/j.still.2024.106434","DOIUrl":"https://doi.org/10.1016/j.still.2024.106434","url":null,"abstract":"The black soil region in Northeast China is an important commodity grain base. In recent years, with the intensification of agricultural activities, the formation and development of gullies on sloping farmland have accelerated, severely affecting food and ecological security. In order to effectively control regional soil erosion, this study comprehensively utilized historical databases of gullies, remote sensing images, field surveys, spatial analysis, and multivariate statistical techniques to reveal the morphological characteristics, development rates, and main driving factors of 116 gullies in typical agricultural watersheds in the low hills of Northeast China. The results showed that linear gully retreat rate in the study area ranged from 4.3 to 8.4 m y<ce:sup loc=\"post\">−1</ce:sup>, with an average of approximately 6.34 m y<ce:sup loc=\"post\">−1</ce:sup>, between 2011 and 2021. The areal gully retreat rate ranged from 90.7 to 1224.4 m<ce:sup loc=\"post\">2</ce:sup> y<ce:sup loc=\"post\">−1</ce:sup>, with an average growth rate of approximately 339.17 m<ce:sup loc=\"post\">2</ce:sup> y<ce:sup loc=\"post\">−1</ce:sup>. Compared with other regions in the world, the development rate of gullies in black soil region of Northeast China is relatively fast, especially in terms of lateral expansion, which is about 7 times greater than longitudinal extension. Gully side-wall retreat (approximately 56.8 m<ce:sup loc=\"post\">2</ce:sup> y<ce:sup loc=\"post\">−1</ce:sup>) was found to be the dominant factor influencing the change in gully area. Environmental variables explained 60.2 % of the variation in gully morphological characteristics, with natural factors having a greater impact on the linear development of gullies than human factors. However, human factors were closely related to lateral expansion. Due to the large proportion of agricultural landscapes and high spatial homogeneity in the study area, micro-topographic features (such as catchment area and elevation) and the spatial configuration of agricultural landscape patches (patch density and edge density) were identified as the main influencing factors of gully erosion development in study area. Therefore, targeted measures and control strategies should be designed based on a comprehensive assessment of terrain factors and landscape pattern indicators to mitigate gully erosion risks. In the future, based on obtaining more three-dimensional data of gullies, empirical coefficient equations should be constructed using gully area and length as independent variables to predict gully volume. This will help identify the main factors influencing sediment and organic matter loss caused by gully erosion in black soil region, and provide technical support for improving the predictive capabilities of gully erosion risks and developing more rational prevention and control strategies.","PeriodicalId":501007,"journal":{"name":"Soil and Tillage Research","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The application of amendments improves properties of salt-affected soils across China","authors":"Guangzhi Huang, Baishun Liu, Xiaotong Jiang, Yanping Liang, Jinghui Cai, Lihua Huang","doi":"10.1016/j.still.2024.106431","DOIUrl":"https://doi.org/10.1016/j.still.2024.106431","url":null,"abstract":"Soil salinization is a major threat to global arable productivity. Chemical amendments are widely used to improve salt-affected soils and have been proven to be effective. However, the effectiveness of amendments varies across different regions and depends on field management practices. To quantify the improvement effects of different amendments on salt-affected soils and how amendment application affects plant productivity and soil properties, we compiled 2061 pairs of data from 92 studies about amendments across China to conduct a meta-analysis. We found that amendments application improved soil quality by reducing soil pH, electrical conductivity (EC), and exchangeable sodium percentage (ESP) with 3.9 %, 18.1 %, and 43.4 %, and improved soil nutrients by increasing soil organic matter (SOM), total nitrogen (TN), available nitrogen (AN), available phosphorus (AP), and available potassium (AK) with 33.6 %, 37.7 %, 35.0 %, 55.3 %, and 32.3 %, and subsequently increased plant emergence rate and yield with 16.2 % and 52.2 % regardless of amendment types, respectively. Specifically, applying mixed amendments led to a significant reduction in soil EC by 33.6 %, whereas the application of inorganic compound decreased soil EC by 8.6 %. Furthermore, biochar application significantly increased SOM by 58.4 % and TN by 46.2 %, while gypsum application increased SOM and TN with only 20.9 % and 17.4 %, respectively. Field management, soil properties, and climate all significantly affected the improvement effect after amendments application. The effects of improving salt-affected soil were strongly correlated with the amount and duration of amendments application, followed by the initial soil salinity and alkalinity. Our findings indicated that the selection of soil amendments should consider not only their quantity but also factors such as cost, the longevity of their effects, and environmental safety.","PeriodicalId":501007,"journal":{"name":"Soil and Tillage Research","volume":"20 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reclamation leads to loss of soil organic carbon and molecular complexity: Evidence from natural to reclaimed wetlands","authors":"Xiaolei Yin, Xiaofei Yu, Lei Qin, Ming Jiang, Xianguo Lu, Yuanchun Zou","doi":"10.1016/j.still.2024.106436","DOIUrl":"https://doi.org/10.1016/j.still.2024.106436","url":null,"abstract":"The molecular diversity of soil organic matter (SOM) is recognised as a key factor influencing soil organic carbon (SOC) accumulation, and the molecular diversity of SOM may change as SOC content changes during land use change. However, the relationship between SOM molecular diversity and SOC before and after natural wetland reclamation remains unclear. Here, we selected seven groups of natural wetland–reclaimed wetlands for spatially paired sampling. SOM molecular diversity was assessed using pyrolysis–gas chromatography–mass spectrometry (py-GC/MS), and factors driving changes in SOM molecular diversity (including microbial community characteristics, enzyme activities, carbon mineralisation rate and soil environmental factors) were investigated. The results showed that molecular diversity (Shannon diversity, Richness) tended to increase with increasing organic carbon content in both wetland and paddy soils. And the soil mineralisation rate decreased with the increase of molecular diversity. This suggests that the relationship between molecular diversity and organic carbon content is not decoupled, even in anaerobic or cyclic anaerobic environments. Therefore, the molecular diversity of soil organic matter can be used as an indicator of the sustainability of soil carbon pools. Microbial biomass and enzyme activity characteristics were important factors influencing soil carbon dynamics and molecular diversity. Molecular diversity decreases with a loss of soil organic carbon after wetland reclamation. Compared to those in natural wetlands, the relative proportions of both aliphatic and alkyl compounds decreased, and the relative proportions of nitrogenous compounds increased in paddy field soils. In addition, the rate of soil carbon mineralisation increases despite the presence of a greater proportion of recalcitrant carbon (phenols and aromatics) in paddy soils. Our results also suggest a positive role for molecular diversity in suppressing soil mineralization rates. Our study provides a molecular diversity-based perspective for understanding wetland soil organic carbon dynamics under the influence of reclamation.","PeriodicalId":501007,"journal":{"name":"Soil and Tillage Research","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Long-term rice–crayfish coculture increases plant lignin but not microbial necromass contribution to soil organic carbon","authors":"Yao Guo, Quanyi Hu, Tianqi Liu, Yunfeng Du, Chengfang Li, Xuelin Zhang, Juan Liu, Cougui Cao","doi":"10.1016/j.still.2024.106424","DOIUrl":"https://doi.org/10.1016/j.still.2024.106424","url":null,"abstract":"Rice–crayfish coculture (RC) has emerged as a transformative agricultural practice in China, significantly influencing soil microorganisms and enhancing soil organic carbon (SOC) accumulation. However, the contribution of plant residues and microbial necromass to the increased SOC within RC systems remains uncertain. This study aimed to investigate phospholipid fatty acids (PLFAs), microbial necromass C (MNC, with amino sugars as biomarkers), plant-derived C (VSC, with lignin phenols as biomarkers) levels, along with soil properties across conventional rice monoculture (RM) and RC systems of 5-, 10-, and 15-yr durations (RC5, RC10, and RC15, respectively). The results showed that long-term RC fields exhibited stronger aggregation, higher soil nutrient levels, organically complexed Fe oxides (Fe<ce:inf loc=\"post\">p</ce:inf>), and lower bulk density and oxidation–reduction potential than those with RM. The SOC levels were significantly higher in RC10 and RC15 than in RM, by 31.8 % and 37.2 %, respectively. Moreover, RC significantly reduced the levels of bacterial (25.3–35.4 %) and fungal (19.5–34.7 %) PLFAs compared with RM, with RC10 exhibiting the lowest levels. With RC duration increasing to 10–15 years, MNC and VSC were respectively higher by 12.4–25.3 % and 48.8–72.4 % than those in RM. Specifically, fungal necromass C, as well as vanillyl- and syringyl-type phenols, showed the most pronounced enhancements. Concurrently, the contribution of VSC to SOC (12.4–25.3 %) significantly increased in the 10 −15-yr RC period compared with RM, whereas MNC decreased proportionally (17.5–18.5 %). SOC and Fe<ce:inf loc=\"post\">p</ce:inf> were the primary factors regulating the contribution of MNC to SOC, whereas the contribution of VSC to SOC was mainly influenced by soil aggregation. Thus, long-term RC improved soil C sequestration primarily by increasing the contribution of plant-derived C rather than that of microbe-derived C. However, the findings of this study indicated that long-term RC might limit microbial biomass, thereby raising concerns about the long-term sustainability of microbial communities in these systems.","PeriodicalId":501007,"journal":{"name":"Soil and Tillage Research","volume":"112 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Soil physical properties and water dynamics under contrasting management regimes at the Morrow Plots","authors":"Peter B. Obour, Yushu Xia, Carmen M. Ugarte, Tony E. Grift, Michelle M. Wander","doi":"10.1016/j.still.2024.106422","DOIUrl":"https://doi.org/10.1016/j.still.2024.106422","url":null,"abstract":"This study investigated changes in soil physical quality and water dynamics arising from continuous cropping at the Morrow Plots, the oldest agricultural experiment in North America. The objectives were to examine the effects of continuous cultivation on soil water retention and determine the optimum water content for tillage (<ce:italic>θ</ce:italic><ce:inf loc=\"post\">OPT</ce:inf>) in a prime agricultural soil. Soil samples collected at 0–5, 5–10, and 10–15 cm depths were used to measure bulk density and water retention using the HyProp 2 and WP4-T Dewpoint Potentiometer. Soil organic carbon (SOC) and soil penetration resistance (PR) were measured to a depth of 15 cm. The soil water retention data were fitted with the Dexter double exponential and van Genuchten models. Neither model consistently fitted all the water retention data across the different management practices. The corn-oat-hay (COH) rotation generally reduced soil bulk density within the 0–15 cm depth by an average of 9 % and PR by 21 % compared to the continuous corn (CC) treatment. The COH rotation slightly increased topsoil water-holding capacity (0–15 cm), although trends varied with fertility regimes. The <ce:italic>θ</ce:italic><ce:inf loc=\"post\">OPT</ce:inf> for the COH and CC estimated by the van Genuchten model was generally wetter than the water content at field capacity (<ce:italic>θ</ce:italic><ce:inf loc=\"post\">FC</ce:inf><ce:italic>)</ce:italic>. In contrast, the <ce:italic>θ</ce:italic><ce:inf loc=\"post\">OPT</ce:inf> estimated by the Dexter model was slightly drier than <ce:italic>θ</ce:italic><ce:inf loc=\"post\">FC</ce:inf>. Despite limitations due to the lack of true replicates and the small sample size at the Morrow Plots, this research underscores the long-term impact of crop rotation on soil hydraulic properties in prime agricultural soils.","PeriodicalId":501007,"journal":{"name":"Soil and Tillage Research","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}