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This study presents a comprehensive investigation of Methane (CH4) emissions in the wetlands of South Sudan, employing an integrated approach that combines TROPOMI satellite data, river altimetry, and hydrological model outputs. TROPOMI data show a strong increase in CH4 concentrations over the Sudd wetlands from 2018 to 2022. We quantify CH4 emissions using these data. We find a twofold emission increase from 2018 to 2019 (9.2 ± 2.4 Tg yr−1) to 2020 to 2022 (16.3 ± 3.3 Tg yr−1). River altimetry data analysis elucidates the interconnected dynamics of river systems and CH4 emissions. We identify correlations and temporal alignments across South Sudan wetlands catchments. Our findings indicate a clear signature of ENSO driving the wetland dynamics and CH4 emissions in the Sudd by altering precipitation patterns, hydrology, and temperature, leading to variations in anaerobic conditions conducive to CH4 production. Significant correlations are found between CH4 emissions and PCR-GLOBWB-simulated soil moisture dynamics, groundwater recharge, and surface water parameters within specific catchments, underscoring the importance of these parameters on the catchment scale. Lagged correlations were found between hydrological parameters and CH4 emissions, particularly with PCR-GLOBWB-simulated capillary rise. These correlations shed light on the temporal dynamics of this poorly studied and quantified source of CH4. Our findings contribute to the current knowledge of wetland CH4 emissions and highlight the urgency of addressing the complex interplay between hydrology and carbon dynamics in these ecosystems that play a critical role in the global CH4 budget. [ABSTRACT FROM AUTHOR]

Summary: Forest soils play a pivotal role as global carbon (C) sinks, where the dynamics of soil organic matter (SOM) are significantly influenced by ectomycorrhizal (ECM) fungi. While correlations between ECM fungal community composition and soil C storage have been documented, the underlying mechanisms behind this remain unclear.Here, we conducted controlled experiments using pure cultures growing on naturally complex SOM extracts to test how ECM fungi regulate soil C and nitrogen (N) dynamics in response to varying inorganic N availability, in both monoculture and mixed culture conditions.ECM species dominant in N‐poor soils exhibited superior SOM decay capabilities compared with those prevalent in N‐rich soils. Inorganic N addition alleviated N limitation for ECM species but exacerbated their C limitation, reflected by reduced N compound decomposition and increased C compound decomposition. In mixed cultures without inorganic N supplementation, ECM species with greater SOM decomposition potential facilitated the persistence of less proficient SOM decomposers. Regardless of inorganic N availability, ECM species in mixed cultures demonstrated a preference for C over N, intensifying relatively labile C compound decomposition.This study highlights the complex interactions between ECM species, their nutritional requirements, the nutritional environment of their habitat, and their role in modifying SOM. [ABSTRACT FROM AUTHOR]

This study aims to address the harmful effects of excessive nitrogen fertilizer by investigating the mobility retardance effect of zeolite on nitrate movement in loam soil columns. Disturbed and undisturbed soil columns, treated with zeolite, as well as control soil columns, were analysed over a span of three years. Breakthrough curves generated from the experiments were evaluated using the HYDRUS1D code with mobile–immobile water (MIM) and dual-permeability (DP) models. Our findings highlight that zeolite application significantly reduced nitrate mobility, with recovery rates decreasing by 8% in disturbed and 11% in undisturbed columns. The DP model, which accurately reflects real soil water flow conditions, outperformed the MIM model in predictive accuracy. This research offers a novel long-term perspective on the benefits of zeolite in enhancing soil properties and mitigating nitrate leaching, recommending the DP model for superior prediction of contaminant transport in structured soils within the vadose zone. [ABSTRACT FROM AUTHOR]

Soil organic carbon is a vital component of the soil carbon pool. Investigation of its composition and dynamics is crucial for enhancing carbon sequestration in soils and for stabilizing the global carbon cycle. In recent years, considerable research has focused on the interactions between soil organic carbon components and their responses to varied land use and agricultural practices. However, the mechanism of soil organic carbon sequestration and response characteristics of soil organic carbon components to soil carbon pools are still subject to some debate. To the best of our knowledge, no researchers have used bibliometric analyses to explore the field of soil organic carbon components. This study thus involved the use of bibliometric techniques to identify research hotspots in the study of organic carbon components over the last 23 years and future trends in research development. Specifically, we performed a comprehensive literature review of 607 documents pertaining to organic carbon components using the Web of Science database, covering the period from 2000 to 2023. Employing CiteSpace, we visualized and analyzed the data across national, institutional, disciplinary, and keyword dimensions. In this study, we conducted a comprehensive, systematic, and quantitative analysis of publications pertaining to organic carbon component research. The results indicate that researchers in the United States and China have substantially influenced the study of soil organic carbon components. Since 2000, the United States has pioneered the study of soil organic carbon components, establishing a foundational role in this field of research. Meanwhile, China leads with the largest number of publications and the most diverse research directions in this field. Among the institutions involved in such research, the University of Chinese Academy of Sciences has the highest number of publications. The investigation of soil organic carbon components within agricultural systems is inherently multidisciplinary, with the most comprehensive research being performed within the soil sciences discipline. At present, the focal areas of research on soil organic carbon components predominantly revolve around the impacts of straw return to fields, varying land-use changes, restoration of vegetation, and the reciprocal effects of soil organic carbon components on the restoration of vegetation. The findings of this work highlight the research hotspots within the field of soil organic carbon components and the emerging trends within this field. This work offers novel insights into the dynamics of soil organic carbon components, potentially guiding future studies in this vital field. [ABSTRACT FROM AUTHOR]

Peatland management practices, such as drainage and restoration, have a strong effect on boreal peatland methane (CH4) fluxes. Furthermore, CH4 fluxes are strongly controlled by local environmental conditions, such as soil hydrology, temperature and vegetation, which are all experiencing considerable changes due to climate change. Both management practices and climate change are expected to influence peatland CH4 fluxes during this century, but the magnitude and net impact of these changes is still insufficiently understood. In this study, we simulated the impacts of two forest management practices, rotational forestry and continuous cover forestry, as well as peatland restoration, on hypothetical forestry-drained peatlands across Finland using the land surface model JSBACH (Jena Scheme for Biosphere–Atmosphere Coupling in Hamburg) coupled with the soil carbon model YASSO and a peatland methane model HIMMELI (Helsinki Model of Methane Buildup and Emission for Peatlands). We further simulated the impacts of climatic warming using two RCP (Representative Concentration Pathway) emission scenarios, RCP2.6 and RCP4.5. We investigated the responses of CH4 fluxes, soil water-table level (WTL), soil temperatures and soil carbon dynamics to changes in management practices and climate. Our results show that management practices have a strong impact on peatland WTLs and CH4 emissions that continues for several decades, with emissions increasing after restoration and clearcutting. Towards the end of the century, WTLs increase slightly, likely due to increasing precipitation. CH4 fluxes have opposing trends in restored and drained peatlands. In restored peatlands, CH4 emissions decrease towards the end of the century following decomposition of harvest residue in the top peat layers despite increasing WTLs, while in drained peatland forests sinks get weaker and occasional emissions become more common, likely due to rising WTLs and soil temperatures. The strength of these trends varies across the country, with CH4 emissions from restored peatlands decreasing more strongly in southern Finland, and forest soil CH4 sinks weakening most in northern Finland. [ABSTRACT FROM AUTHOR]

AbstractIntegration of organic and inorganic fertilizers is inevitable to sustain intensive agricultural production; however, assessment of combination of organic and inorganic fertilizers on soil phosphorus (P) fractions is yet to be understood. This study aims to investigate availability, distribution, and fractions of soil P as influenced by long-term fertilization under soybean-based cropping systems in Vertisol. Soil samples were collected during 2021 from a 17-year-old field experiment with six treatments viz., T1: 100% Organic, T2: 75% Organic + 25% Innovative approach, T3: 50% Organic + 50% Inorganic, T4: 75% Organic + 25% Inorganic, T5: 100% Inorganic, and T6: State recommendation under soybean-wheat, soybean-mustard, and soybean-chickpea cropping systems at two soil depths after wheat, mustard, and chickpea, and examined for 0.5 M NaHCO3-P, total P, inorganic P, and different P fractions namely, saloid-P (1 M NH4Cl), aluminium-P (0.5 M NH4F), iron-P (0.1 M NaOH), calcium-P (0.25 M H2SO4), and reductant soluble-P (0.3 M Na3C3H6O7 + 1 M NaHCO3 + Na2S2O3). Results demonstrates that continuous fertilization using organic, inorganic, and their combination influences soil P dynamics. Soybean-chickpea system was found better in sustaining P availability. Higher NaHCO3-P was observed under 50% organic + 50% inorganic plot. Inorganic fertilizer dominated soil P accumulation as observed from higher inorganic fractions, and total P. Addition of organic manure could contribute to solubilization of fixed-P fractions and renders plant available form. It can be concluded that fertilization with organic manures and inorganic fertilizer should be followed so that 25–50% costly P-fertilizers could be saved for crop production under soybean-based cropping systems in Vertisols. [ABSTRACT FROM AUTHOR]

Soil salinization refers to the accumulation of water‐soluble salts in the upper part of the soil profile. Excessive levels of soil salinity affects crop production, soil health, and ecosystem functioning. This phenomenon threatens agriculture, food security, soil stability, and fertility leading to land degradation and loss of essential soil ecosystem services that are fundamental to sustaining life. In this review, we synthesize recent advances in soil salinization at various spatial and temporal scales, ranging from global to core, pore, and molecular scales, offering new insights and presenting our perspective on potential future research directions to address key challenges and open questions related to soil salinization. Globally, we identify significant challenges in understanding soil salinity, which are (a) the considerable uncertainty in estimating the total area of salt‐affected soils, (b) geographical bias in ground‐based measurements of soil salinity, and (c) lack of information and data detailing secondary salinization processes, both in dry‐ and wetlands, particularly concerning responses to climate change. At the core scale, the impact of salt precipitation with evolving porous structure on the evaporative fluxes from porous media is not fully understood. This knowledge is crucial for accurately predicting soil water loss due to evaporation. Additionally, the effects of transport properties of porous media, such as mixed wettability conditions, on the saline water evaporation and the resulting salt precipitation patterns remain unclear. Furthermore, effective continuum equations must be developed to accurately represent experimental data and pore‐scale numerical simulations. Plain Language Summary: Soil salinization refers to the excess accumulation of salt in soil to a level that affects crop production and ecosystem functioning. This poses existential threat to sustainable agriculture, food security, and soil fertility. Soil salinization is considered as one of the major drivers for desertification, resulting in a persistent loss of ecosystem services. It also imposes nutritious imbalances in plants that may induce significant alterations in Earth's organisms, ecosystems, and biodiversity. We synthesized recent advances on soil salinization at different length and time scales, ranging from pore to global scale, offering new insights, and presenting future perspective on the key challenges and open questions on soil salinization. Key Points: Soil salinization poses existential threat to sustainable agriculture, food security, and soil fertilityWe synthesized recent advances on soil salinization at different length scales, ranging from pore to global scaleWe offer new insights and present future outlook on the key challenges and open questions related to soil salinization [ABSTRACT FROM AUTHOR]

Predicting soil–water dynamics in Moistube irrigation (ΜΤΙ) favours understanding ΜΤΙ functioning mechanisms and technical parameter design. This study proposed a physically based infiltration (PH) model extending the Green–Ampt (GA) model to a two-dimensional polar coordinate system. We treated Moistube as a clay and considered the infiltration from internal Moistube to surrounding soils. The performances of the PH model, together with a semi-physical–empirical (PH–EM) model and a numerical simulation (NUM) model, were evaluated based on regulated working pressure head (WPH) experiments. A HYDRUS 2D model was used based on experimental design to reproduce the soil–water dynamics by assigning Moistube and soil two sets of hydraulic parameters. WPH increase or decrease treatments were applied to Moistube. The Moistube discharge rate, infiltration volume, and wetting front (WF) advance were analyzed and predicted by three models. The results showed that cumulative infiltration, Moistube discharge, and effective saturation around Moistube were enhanced or abated under WPH increase or decrease, with WF accelerating or decelerating. The modelled effective saturation varied between 0.45 and 0.70, providing suitable moist conditions for crops. Percentage of bias (PBIAS) and mean absolute percentage relative error (MAPRE) were employed to evaluate model performances. Three models well-predicted infiltration characteristics and WF advance but differed in accuracy. The PH model overestimated and underestimated the Moistube discharge rate in early and later phases. The prediction accuracy in WF varied across infiltration phases and WPH modes. The PH–EM model yielded accurate results due to its empirical attribute. The NUM model produced novel phenomena of infiltration characteristics at WPH adjustment points, i.e., the discharge rate exponentially decreased over time after the WPH increased but presented restraining followed by rebounding trends after the WPH decreased. The NUM model strongly depended on the selection of the Moistube hydraulic parameters. Extending the GA model to a two-dimensional polar coordinate system by treating Moistube as a clay was practicable in modelling soil water dynamics, thereby contributing to designing and optimizing MTI technical indexes. [ABSTRACT FROM AUTHOR]

Soil carbon (C) and nitrogen (N) are vital for enhancing tea production and ensuring the sustainability of tea plantation ecosystems. However, research on the dynamics of soil C and N pools and their associated microbial mechanisms in tea plantations with varying cultivation durations is scarce. We compared soil samples from a forest and two tea plantations—young established (YTP) and century-old (OTP)—to assess changes in soil C and N concentrations and the impact of fungal community structure on these elements. Soil organic carbon (SOC) and total nitrogen (TN) were markedly higher in OTP than in the YTP and forest (65.9% and 30.1%, respectively, relative to YTP). Eurotiomycetes in the YTP group accounted for a relatively higher proportion at 51.6%, surpassing its presence in both the forest (14.3%) and OTP (4.78%) groups and it can be the main microbial factor affecting the C cycle in tea plantation soils and facilitating SOC mineralization. Enhancing planting years or changing land use patterns improves fertilizer and biomass sedimentation and increases the relative abundance of Eurotiomycetes in the soil and the C sink potential of tea plantations. This study provides valuable insights into the role of soil C and N dynamics and fungal communities in tea plantation ecosystems, highlighting the importance of managing these factors for sustainable tea production. [ABSTRACT FROM AUTHOR]

Background: The current transformation of the entire energy system leads to a large‐scale expansion of extra‐high‐voltage underground transmission lines (UTL). Knowledge of the impact on soil temperature and soil moisture dynamics is fundamental for environmental evaluation. Aims: We investigated the impact of an existing 320 kV underground cable in continuous operation on soil temperature and moisture dynamics. Methods: A soil‐monitoring programme was established at four study sites in Western Germany. Data were continuously recorded in soil up to 120 cm depth using soil sensors over a period of 1 year. Results: Soil warming was in a range of 0.6 K in the topsoil, approx. 1–1.3 K in the rooting zone and 1.7 K in the subsoil at 120 cm depth and was restricted mainly to the immediate vicinity of the cable route. Likewise, the impact on soil moisture dynamics was on average in a range of −1.00 wt.‐% in 0–60 cm depth and −2.45 wt. 2‐% in the subsoil relative to control. Although at a calculated maximum load capacity of 100% in regular operation, soil warming might remain moderate, with 1.5 K in the topsoil, 2.3–3.1 K in the rooting zone and 4.1 K in the subsoil. Conclusions: It is assumed that the reasons for the low‐to‐moderate influence of the UTL are to be found in the operational cable load (on average 65%), heat loss of cables (approx. 12 W m−1 per cable) and the quality of the imbedding material for the cables. [ABSTRACT FROM AUTHOR]

Background: Tropical ecosystem functioning is influenced by seasonal fluctuations in precipitation, but the impact on soil nutrient cycling and microbial stoichiometry is not fully understood. Aim: This study investigates the magnitude of intra‐annual fluctuations in nutrient availability and microbial biomass in a tropical forest soil by examining carbon (C), nitrogen (N), and phosphorus (P) pools. Methods: We analyzed the total, extractable, and microbial C, N, and P contents and their stoichiometry in Terra Firme Ferralsols, representative for the central Amazon basin. Results: We observed intra‐annual variations in resource availability, particularly between wet and dry seasons. Despite relatively stable total C, N, and P stocks throughout the year, we observed a decrease in extractable organic C and available (Olsen) P and an increase in extractable N in the dry season compared to the wet season. Microbial biomass pools and stoichiometry also varied across sampling dates and soil depths: relative to microbial‐C and ‐N, microbial‐P decreased in both wet and dry season and increased in the transition from wet to dry season. Conclusions: Our research highlights intra‐annual variation in nutrient pools, particularly dynamic microbial carbon and nutrient fractions, in weathered tropical forest soils. [ABSTRACT FROM AUTHOR]

Silage maize (Zea mays L.) intensification to maximise biomass production increases greenhouse gas emissions, accelerates climate change and intensifies the search for alternative bioenergy crops with high carbon (C) sequestration capacity. The perennial cup‐plant (Silphium perfoliatum L.) not only serves as a viable bioenergy source but may also be a promising soil C conservator. However, the dynamics of soil organic C (SOC) under the C3 cup‐plant, exposed to moderate drought conditions, that reduces growth rate without causing crop failure, compared with the drought‐tolerant C4 maize, remains unexplored. Here, we investigated in a lysimeter experiment the effects of moderate drought stress on crop growth and soil CO2 efflux under cup‐plant and silage maize compared with well‐watered conditions. Soil CO2 efflux along with root and shoot biomass, soil moisture and temperature as well as SOC and nitrogen (N) were measured over three consecutive years. Irrespective of the watering regime, cup‐plant induced a greater soil CO2 efflux (16% and 23% for 2020 and 2021, respectively), which was associated with higher root and shoot biomass compared with silage maize suggesting a substantial contribution of the roots to total soil CO2 efflux. In addition, soil CO2 efflux correlated negatively with soil dissolved N and positively with microbial C:N imbalance suggesting that low soil N availability influences soil CO2 efflux through processes related to N‐limitation such as N‐mining. Strikingly, moderate drought had no effect on soil CO2 efflux and C content and microbial biomass C, but increased dissolved organic C and microbial biomass N in both crops suggesting a complex interplay between C availability, N‐limitation and microbial adaptation under these conditions. Although cup‐plant increased soil CO2 efflux, the observed higher root and shoot biomass even under moderate drought conditions suggests a similar soil C management as silage maize; however, this still requires longer‐term investigation. [ABSTRACT FROM AUTHOR]

Soil carbon dioxide (CO2) fluxes are a critical component in understanding carbon sequestration. In sub-Saharan Africa, empirically measured CO2 emissions data from diverse land-use systems is limited. Soil CO2 emission rates were measured in the Limpopo Province, South Africa for 12 months at two-week intervals in natural systems (forest and shrubland) and commercially managed orchards (avocado and citrus) to establish seasonal dynamics of soil CO2 emissions across these land-use systems. The results showed a variation in emission rates with the variation depending on the season. In the spring and winter, soil CO2 emission rates in citrus were four times higher than in the shrubland due to higher moisture levels. However, in the summer season, the forest emission rates were 40% higher than in citrus due to higher soil organic carbon content. Organic carbon stocks were higher in the forest (1.19 kg/m2) compared to the other land uses. This study revealed differences in soil CO2 emission rates among land-use systems, with the cumulative amount of CO2 emitted over a 12-month period following the order: forest (39.3 tons/ha) > citrus (36.1 tons/ha) > shrubland (28.1 tons/ha) > avocado (26.9 tons/ha). Thus, understanding the emission patterns from various ecosystems can inform strategies for mitigating greenhouse gas emissions. [ABSTRACT FROM AUTHOR]

Amidst burgeoning socioeconomic development, anthropogenic activities have exacerbated soil erosion. This erosion, characterized by its brief duration, high frequency, and considerable environmental degradation, presents a major challenge to ecological systems. Therefore, it is imperative to regulate and remediate erosion–prone, anthropogenically disturbed parcels, with dynamic change detection (CD) playing a crucial role in enhancing management efficiency. Currently, traditional methods for change detection, such as field surveys and visual interpretation, suffer from time inefficiencies, complexity, and high resource consumption. Meanwhile, despite advancements in remote sensing technology that have improved the temporal and spatial resolution of images, the complexity and heterogeneity of terrestrial cover types continue to limit large–scale dynamic monitoring of anthropogenically disturbed soil erosion parcels (ADPSE) using remote sensing techniques. To address this, we propose a novel ISegFormer model, which integrates the SegFormer network with a pseudo–residual multilayer perceptron (PR–MLP), cross–scale boundary constraint module (CSBC), and multiscale feature fusion module (MSFF). The PR–MLP module improves feature extraction by capturing spatial contextual information, while the CSBC module enhances boundary prediction through high– and low–level semantic guidance. The MSFF module fuses multiscale features with attention mechanisms, boosting segmentation precision for diverse change types. Model performance is evaluated using metrics, such as precision, recall, F1–score, intersection over union (IOU), and mean intersection over union (mIOU). The results demonstrate that our improved model performs exceptionally well in dynamic monitoring tasks for ADPSE. Compared to five other models, our model achieved an mIOU of 72.34% and a Macro–F1 score of 83.55% across twelve types of ADPSE changes, surpassing the other models by 1.52–2.48% in mIOU and 2.25–3.64% in Macro–F1 score. This work provides a theoretical and methodological foundation for policy–making in soil and water conservation departments. [ABSTRACT FROM AUTHOR]

Different canopy resistance (rc) parameterization has been used in land surface models to simulate actual evapotranspiration (ETc) and soil hydraulic variable for crop fields. However, the influence of rc parameterization on evapotranspiration (ET) partitioning and soil water dynamics has not been fully investigated with consideration of the coupled soil water and vapor physics. This study investigated the influential mechanisms of five rc methods (viz., Jarvis, Katerji-Perrier, Massman, Kelliher-Leuning, and Farias) on ET partitioning and soil water contents in an irrigated maize field under a semiarid climate through a soil water and vapor transfer model. The Jarvis method presented the best ET results (R2 = 0.86 and RMSE = 0.71 mm·d-1). Different rc parameterization mainly altered the simulated amount of soil water contents, while not changed the response of soil water dynamics to irrigation events. By the integrated analysis of the ET partitioning and root-zone water budget, different rc methods varied in the choice of the optimum irrigation water use strategies. This study identified the direct and indirect impacts of rc on the ET partitioning and emphasizes the necessity of both the ET partitioning and water supply sources in the decision-making for irrigation water management in semiarid regions. [ABSTRACT FROM AUTHOR]

Plant economics, the way plants allocate and utilize resources, affect multiple soil processes through interactions with root and associated microbial communities. However, the interplay between plant economics and microbial ecological strategies remains poorly understood, which is crucial for integrated manipulation of plant‐ and microbe‐mediated functions in mitigating climate change and sustaining soil health.We used a field experiment with 11 cover crop species grown monocultures in the same base soil to test whether microbial ecological strategies are associated with plant economic strategies and if their interactions are linked to soil functions. A principal component analysis (PCA) was performed on root and leaf traits to identify the loadings of cover crop species on the plant trait space. Metagenomic analysis of rhizosphere microbial communities was conducted to infer their ecological strategies based on genetically encoded community‐aggregated traits.We found a synchronous relationship between the conservation gradient of plant economic strategies and the trade‐offs in microbial ecological strategies. Conservative plant strategists, such as Lolium multiflorum, Triticum turgidum and Brassica juncea, fostered microbial communities characterized by high growth yield potentials (Y‐strategies). This included increased microbial carbon fixation pathways, citrate cycle, ribosome and valine, leucine and isoleucine biosynthesis. As a result, microbial metabolic efficiency improved, shown by higher microbial biomass carbon content and a lower metabolic quotient (qCO2), led to enhanced soil organic carbon accumulation. In comparison, acquisitive plants like Astragalus sinicus, Vicia villosa, Trifolium incarnatum and Medicago sativa stimulated microbial resource‐acquisition strategies (A‐strategies). This included enhanced bacterial chemotaxis, secretion systems, biotin metabolism and cell motility pathways, which in turn increased soil exoenzyme activity and accelerated soil nitrogen mineralization. Consequently, these species enhanced soil nitrogen availability and had substantial feedbacks on subsequent main crop productivity.Synthesis. This study demonstrates how plant economic strategies influence the balance between different microbial ecological strategies, specifically the trade‐offs in Y‐ and A‐strategies. These interactions exert control over carbon and nitrogen dynamics in the soil ecosystem. The findings provide insights for implementing nature‐based solutions to improve agroecosystem management practices. [ABSTRACT FROM AUTHOR]

A comprehensive understanding of the formation of mineral‐associated organic matter (MAOM) is a prerequisite for the sustainable management of soil carbon (C) and the development of effective long‐term strategies for C sequestration in soils. Nevertheless, the precise manner by which microbial and mineral properties drive MAOM formation efficiency and its subsequent response to elevated temperature at the regional scale remains unclear. Here, we employed isotopically labelled laboratory incubations (at 15°C and 25°C) with soil samples from a ~3000 km transect across the Tibetan Plateau to elucidate the mechanisms underlying MAOM formation and its temperature response. The results indicated that both mineral protection and microbial properties were critical predictors of MAOM formation across the geographic gradient. The efficiency of MAOM formation was found to increase with the content of iron (Fe) oxides and their reactivity [i.e., the ratio of poorly crystalline Fe oxides to total Fe oxides (Feo:Fed)] but to decrease with the relative abundance of Gammaproteobacteria and Actinobacteria across the plateau. Moreover, a notable decline in MAOM formation efficiency was observed under elevated temperatures, which was concomitant with a reduction in the content and reactivity of Fe oxides, as well as the microbial assimilation of the labelled substrate. The attenuation of mineral–organic associations was identified as the primary factor contributing to the warming‐induced reduction in MAOM formation. These findings highlight the necessity of incorporating organo–mineral associations and microbial properties into Earth System Models to accurately project soil C dynamics under changing climate. [ABSTRACT FROM AUTHOR]

Numerical analysis of soil vibrations due to vibrating foundations: Guidance for model design Geotechnical engineers are increasingly concerned with wave propagation problems. Manufacturers of geotechnical analysis software added features for soil dynamic analyses to their products initially devised for static geotechnical analyses. Though, users often lack the experience for conducting such advanced numerical analyses. Working groups 1.4 "Soil dynamics" and 1.6 "Numerical analyses in geotechnical engineering" of DGGT German Society for Geotechnical Engineering established a joint subgroup "Numerical analyses in soil dynamics" to address this shortcoming. The present paper presents the work of the subgroup so far and provides some guidance on conducting numerical analyses in soil dynamics. [ABSTRACT FROM AUTHOR]

There are major gaps in our understanding of how Mediterranean ecosystems will respond to anticipated changes in precipitation. In particular, limited data exists on the response of deep soil carbon dynamics to changes in climate. In this study we wanted to examine carbon and nitrogen dynamics between topsoils and subsoils along a precipitation gradient of California grasslands. We focused on organic matter composition across three California grassland sites, from a dry and hot regime (~ 300 mm precipitation; MAT: 14.6 ∘ C ) to a wet, cool regime (~ 2160 mm precipitation/year; MAT: 11.7 ∘ C ). We determined changes in total elemental concentrations of soil carbon and nitrogen, stable isotope composition (δ13C, δ15N), and composition of soil organic matter (SOM) as measured through Diffuse Reflectance Infrared Fourier Transformed Spectroscopy (DRIFTS) to 1 m soil depth. We measured carbon persistence in soil organic matter (SOM) based on beta ( β ), a parameter based on the slope of carbon isotope composition across depth and proxy for turnover. Further, we examined the relationship between δ15N and C:N values to infer SOM's degree of microbial processing. As expected, we measured the greatest carbon stock at the surface of our wettest site, but carbon stocks in subsoils converged at Angelo and Sedgwick, the wettest and driest sites, respectively. Soils at depth (> 30 cm) at the wettest site, Angelo, had the lowest C:N and highest δ15N values with the greatest proportion of simple plant-derived organic matter according to DRIFTS. These results suggest differing stabilization mechanisms of organic matter at depth across our study sites. We infer that the greatest stability was conferred by associations with reactive minerals at depth in our wettest site. In contrast, organic matter at our driest site, Sedgwick, was subject to the most microbial processing. Results from this study demonstrate that precipitation patterns have important implications for deep soil carbon storage, composition, and stability. [ABSTRACT FROM AUTHOR]

Fragipans are dense subsurface soil layers that severely restrict root penetration and water movement. The presence of shallow fragipan horizons limits row crop production. We hypothesized that the roots of cover crop might improve soil physiochemical properties and biological activity, facilitating drainage and increasing effective soil depth for greater long-term soil water storage. To evaluate annual ryegrass as one component of a cover crop (CC) mix for promoting the characteristics and distribution of soil water, on-farm studies were conducted at Marion and Springerton in southern Illinois, USA. Soil samples were collected at 15 cm increments to 60 cm (Marion) and 90 cm (Springerton) depths during the fall of 2022. Both sites had low total soil carbon and nitrogen contents and acidic soil pH (≤6.4). A soil water retention curve was fitted using the van Genuchten equation. At Springerton, the CC treatment increased saturated (thetaS) and residual (thetaR) soil water contents above those of the no cover crop (NCC) at the 60–75 cm and 75–90 cm depths. Changes in volumetric soil water content were measured using a multi-depth soil water sensor for the Springerton site during late July to early August of the soybean growing phase of 2022; NCC had higher soil water than CC within the 0–15 cm depth, but CC had higher soil water than NCC at the 30–45 cm depth. These findings indicate that cover crop mix has the potential to improve soil water movement for soils with restrictive subsoil horizon, possibly through reducing the soil hydraulic gradient between the surface and restrictive subsurface soil layers. [ABSTRACT FROM AUTHOR]

The diversification of cropping sequences has a positive impact on soil organic carbon, while improving nutrient cycling and crop yields. The objective of this research was to assess amylase, cellulase, C and N dynamics, and maize yield on a low fertility oxisol in the Brazilian Cerrado. The experiment was conducted under field conditions during three maize crop succession cycles. The treatments consisted of cultivating maize during the summer, after sorghum and lablab cropped as green manure and fallow during the winter. Higher maize yields were achieved by sorghum–maize succession compared to monocropping, due to higher N fertilizer and biomass inputs to topsoil. Sorghum–maize succession also provided a higher proportion of stable C and N compared to other successions. Maize yields declined as tropical soil fertility intrinsically decreased along three crops succession cycles. Cellulase activity decreased over time, whereas amylase activity increased as the plant residues were already in advanced stages of decomposition. The sorghum–maize crop succession stood out compared to lablab and fallow as it provided the highest maize yields, while maintaining higher C and N levels, and amylase activity. This better performance was likely due to larger amounts of incorporated biomass and better mineral N fertilizer management. [ABSTRACT FROM AUTHOR]

Aims: Tea plantation soils have great potential for carbon (C) sequestration because of the perennial nature of tea plants. Long-term tea plantations can lead to soil acidification. However, how the dynamics of soil organic carbon (SOC) stocks and its molecular composition respond to tea plantation establishment remains unclear. Methods: Amino sugars and lignin phenols were used as biomarkers for microbial necromass and plant lignin components to investigate the changes in their distribution to SOC across a tea plantation chronosequence (1-, 7-, 16-, 25-, and 42-year old), thus providing a holistic perspective of SOC formation and stabilization. Results: Long-term tea plantation increased SOC content and the levels of amino sugars and lignin phenols, but reduced microbial biomass C despite an increase in dissolved organic C. Comparatively, the contribution of microbial-derived C to SOC was lower than that of plant-derived C. Despite the increased levels of amino sugars over the time-course, the proportion of bacterial-derived C in the SOC decreased, reflecting diluted contributions of bacterial residues to the SOC pool. Further, the decrease in soil pH and microbial biomass C over time resulted in shifts in the contribution of bacterial and fungal residues the pool, with an increase in the contribution of fungal residues. Conclusions: These findings provide new insights into changes in SOC accumulation in long-term tea plantations, highlighting an increase in soil C sequestration associated primarily by the presence of lignin phenols. This build up is affected by abiotic (physical and chemical protection) and biotic factors including increased dominance of fungal residues inputs. [ABSTRACT FROM AUTHOR]

Background and aims: Dissolved organic matter (DOM) stands out as a highly active component within the organic matter pool. It is hypothesized to play a crucial role by adsorbing onto minerals and serving as a precursor for soil aggregates. However, the impact of DOM substrate types and addition levels on the intricate dynamics of soil aggregates remains elusive. Methods: A 28-day short-term incubation experiment was conducted to investigate the responses of a Japanese Andisol to different DOM substrates, exploring the influence of three DOM substrates and two concentration levels. REOs concentrations in three aggregate fractions were measured on 0, 7, 14, and 28 days of incubation to calculate the aggregates transformation paths and relative aggregate change. Results: DOM addition significantly increased aggregate stability in Andisols soil, evident in the elevated mean weight diameter (MWD) compared to the control (CK) treatment. The change of aggregate stability during incubation is determined by both DOM types and addition levels. The N-Acetyl-D(+)-Glucosamine (NADG) treatment, peaking at 14 days, whereas the vanillin (VAN) treatment reaching the highest MWD value before incubation (0 days). The increase in aggregate stability was reflected in the transformation paths of aggregates. NADG treatment, VAN treatment, and the NADG&VAN (MIX) mixture all contributed to reduced macroaggregate breakdown and inhibited the microaggregates breakdown. Furthermore, the relative changes in aggregate turnover exhibited varying trends across treatments. Regarding macroaggregate dynamics, the addition of vanillin, especially in the 100%VAN and 100%MIX treatments, significantly enhanced macroaggregate formation, with an increase of over 30% in the 100%MIX treatment after 28 days. Microaggregate dynamics varied among treatments. In the 100%NADG and 100%VAN treatments, there was an initial increase from 0 to 7 days, succeeded by a decrease from 7 to 28 days. The 50%VAN and 50%MIX treatments exhibited an increasing trend from 0 to 14 days, followed by a decrease from 14 to 28 days. Conclusion: Overall, these findings highlight the important role of DOM in aggregate dynamics and suggest that the types and addition levels of DOM can significantly impact soil aggregate turnover pathways. [ABSTRACT FROM AUTHOR]

Background and Aims: Plant and microbial-derived carbon (C) constitute the soil C pool and determine its response to N deposition. However, the response of plant and microbial-derived C to exogenous N input in forest soils, accounting for 70% of the global soil C, remains unclear. Methods: We conducted a global meta-analysis to assess the response of microbial-derived C (indicated by amino sugars) and plant-derived C (indicated by lignin phenols) in forest soils to the increasing N deposition. Results: Results revealed significant increases in both total amino sugar and lignin phenols, with a more pronounced increase in temperate forest soils experiencing low-level N addition. Glucosamine (GluN) exhibited no significant change, but muramic acid (MurN) was increased following N addition. Positive correlations were observed between total amino sugars and SOC and total phospholipid fatty acid (PLFA), as well as between MurN and bacterial PLFA. Lignin phenols were positively correlated with litterfall but unrelated to root biomass. Conclusion: N deposition enhanced the accumulation of microbial and plant-derived C in soils, particularly in N-deficient temperate forest soils. The accumulation of microbial-derived C is primarily attribute to the increased microbial biomass and bacterial-derived C, while the accrual plant-derived C is mainly associated with the increase in aboveground C input caused by N addition. These findings collectively uncover the general patterns and mechanisms of microbial and plant-derived C in forest soils in response to N deposition, providing new insights into interpreting soil C dynamics and predicting soil C pools in forest ecosystems facing future climate changes. [ABSTRACT FROM AUTHOR]

Exploring the temporal evolution dynamics of different soil organic nitrogen (N) components under different water–N management practices is a useful approach to accurately assessing N supply and soil fertility. This information can provide a scientific basis for precise water and N management methods for greenhouse vegetable production. The objective of this study was to investigate the effects of optimized irrigation and nitrogen management on the dynamics of soil organic nitrogen fractions, soil properties, and crop growth. This research was conducted from 2017 to 2023 in a greenhouse vegetable field in North China. Four treatments were applied: (1) high chemical N application with furrow irrigation (farmers' practice, FP); (2) no chemical N application with drip irrigation (DN0); (3) 50% N of FP with drip irrigation (DN1); and (4) 75% N of FP with drip irrigation (DN2). The volume in drip irrigation is 70% of that in furrow irrigation. The results showed that in 2023 (after seven years of field trials), compared with FP, the soil organic carbon (SOC), total N, and water use efficiency of the DN1 and DN2 treatments increased by 15.9%, 11.4%, and 11.3% and 7.7%, 47.2% and 44.6%, respectively. However, there was no significant difference in the total crop yield except in the DN0 treatment. Soil organic N was mostly in the form of acid-hydrolyzed N (AHN). After seven years of optimized irrigation and N management, the DN1 treatment significantly increased the content of ammonium N (AN) and amino sugar N (ASN) in AHN compared with the FP treatment. The results of further analysis demonstrated that SOC was the main factor in regulating AHN and non-hydrolyzable N (NHN), while the main regulatory factors for amino acid N (AAN) and ASN in the AHN component were dry biomass and water use efficiency, respectively. From a time scale perspective, optimization of the water and N scheduling, especially in DN1 (reducing the total irrigation volume by 30% and the amount of N applied by 50%), is crucial for the sustainable improvement of soil fertility and the maintenance of vegetable production. [ABSTRACT FROM AUTHOR]

The reliance on soil acidity correctives and mineral fertilizers poses a threat to food production due to the finite nature of these resources and their susceptibility to price volatility from importation. Soil remineralizers have emerged as a sustainable alternative. This study assessed silicate agrominerals as soil remineralizers to replace limestone, gypsum, and conventional fertilizers in a no-tillage system. Conducted in a tropical climate on sandy/medium-textured Ultisol, twelve treatments (combinations of liming, gypsum, mineral fertilization, and remineralizer) were tested for their effects on soybean and sorghum agronomic traits. Applying a remineralizer at 2500 kg ha−1 enhanced soybean productivity by 15% and sorghum by 35% in succession, along with increases in P, S, Ca, Mg, sum of bases (SB), cation exchange capacity (CEC), base saturation (V%) in the 0–0.20 m layer and organic matter in the 0–0.40 m layer, benefiting soil microbiological parameters, with the treatment combining all four products improving soil fertility; however, for better crop productivity, split applications appear to be an alternative to avoid nutrient imbalance. Due to the finer particle size of the remineralizer, which allows faster nutrient release, further research is recommended to investigate the long-term impacts on soil microbiota dynamics, optimal doses and combinations, and economic viability across various soil types and climates. [ABSTRACT FROM AUTHOR]

Eucalyptus has emerged as a game-changer in Bangladesh's forestry sector due to its high productivity in dry and infertile areas. To understand farmers' preference for eucalyptus despite government bans, comprehensive surveys and on-farm experiments were conducted in Dinajpur, Bangladesh. Additionally, Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU) conducted small-scale field and pot experiments to evaluate the allelopathic impacts of eucalyptus roots, bark, and leaf extracts on rice yield during the Boro and Aus seasons. Our survey revealed that, despite challenges like water competition, leaf contamination, hindered tillage, and reduced soil fertility, farmers successfully grow rice, maize, potato, tomato, mustard, and grass alongside eucalyptus trees. Farmers are motivated by eucalyptus's potential to enhance economic returns, evidenced by a high benefit–cost ratio of 1.22‒1.81 and a 10-year net compensation of US$5552–9918, even after yield losses. Our Dinajpur field experiment showed that rice yield was relatively unaffected at 5 m from the tree base, but closer distances reduced yield by 56.77 and 42.10% in Boro and Aus seasons, respectively, compared with sole rice systems. Field and pot experiments at BSMRAU showed a severe decline in rice yields with increasing tree leaf coverage and eucalyptus extract concentrations (0 to 100% concentration), likely due to allelochemicals. Surprisingly, areas near the eucalyptus base showed enhanced total nitrogen and organic carbon levels, credited to substantial leaf litter deposition. Our research decisively proves that eucalyptus and eucalyptus-based agroforestry systems boost farmers' socio-economic status by offering valuable forest resources and debunking harmful misconceptions. [ABSTRACT FROM AUTHOR]

The security of water resources in the desert steppe ecosystem faces threats due to large-scale vegetation restoration. Dynamic changes in soil moisture result from the interplay of precipitation replenishment and evapotranspiration depletion, both directly regulated by vegetation and soil. To achieve sustainable vegetation restoration, understanding the quantifiable impacts of precipitation, evapotranspiration, soil, and vegetation on spatiotemporal soil moisture dynamics is crucial. However, these effects remain insufficiently understood. In this study, against the background of an extreme drought from 2020 to 2022, four typical herbaceous plant communities—Agropyron mongolicum, Sophora alopecuroides, Stipa breviflora, and Achnatherum splendens—were selected for investigation in Yanchi County, Ningxia Province, Northwest China. We analyzed dynamic changes in soil moisture at 0–120 cm during depletion, recovery, and stability periods, quantifying the relative contributions of precipitation, evapotranspiration, soil clay/sand ratio (C/S), and biomass to soil moisture dynamics. The results showed that the 0–120 cm soil moisture of the four plant communities in the depletion, recovery, and stability periods decreased from 7.38% to 6.81%, 11.22% to 8.08%, and 11.70% to 5.84%, respectively. In terms of relative importance, precipitation and evapotranspiration accounted for 25% to 50% and 23.6% to 39.6% of the total explanation for the soil moisture in each plant community, respectively. C/S primarily influenced soil moisture in the S. alopecuroides community, demonstrating a significant positive correlation with soil moisture and accounting for 49.1% of the total explanation. Biomass mainly affected soil moisture in the A. mongolicum, S. breviflora, and A. splendens communities and had a significant negative correlation with soil moisture, accounting for 5.7%, 13.1%, and 9.8% of the total interpretation, respectively. The continuous extreme drought caused the soil moisture deficit to extend from the shallow to the deep layers. The effects of C/S and biomass on soil moisture occurred in leguminous and gramineous communities, respectively. [ABSTRACT FROM AUTHOR]

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Expansive soils, known for their susceptibility to early damage due to their swelling and shrinkage properties, pose a significant technical challenge in geotechnical engineering. This study explores the optimization of microbial-induced improvement of these soils, emphasizing the pivotal role of temperature, pH, and time on both microbial growth dynamics and the soil's swell-shrink behavior. A series of microbial growth and expansive soil swell-shrink tests were conducted, employing response surface methodology (RSM) to develop regression models that delineate the optimal conditions for microbial solution concentration and the free swelling ratio. The findings indicate that temperature and curing time exert a more pronounced influence on these parameters than pH. Notably, microbial solution concentration exhibits a peak with increasing temperature, while the free swelling ratio inversely declines. The curing time's effect is characterized by an initial peak in microbial solution concentration followed by a gradual decrease, with the free swelling ratio of the soil consistently diminishing. The optimization analysis pinpoints the optimal conditions at 32 °C, pH 6.5, and a curing duration of 48 h, where the reduction in both microbial solution concentration and free swelling ratio is maximized. Under these conditions, microorganisms are used for improvement, the microbial solution's OD600 value peaks at 1.996, significantly reducing the expansive soil's free swelling ratio from 169 to 64.3%. [ABSTRACT FROM AUTHOR]

Spring snowmelt has a significant impact on the hydrological cycle in seasonally frozen soil areas. However, scholars hold differing, and even opposing, views on the role of snowmelt during the thawing period in groundwater recharge. To explore the potential recharge effects of spring snowmelt on groundwater in seasonal frozen soil areas, this study investigated the vadose zone dynamics controlled by soil freeze–thaw processes and snowmelt infiltration in the Northeast of China for 194 days from 31 October 2020 to 12 May 2021. Responses of groundwater level and soil moisture to snowmelt infiltration show that most snowmelt was infiltrated under the site despite the ground being frozen. During the unstable thawing period, surface snow had already melted, and preferential flow in frozen soil enabled the recharge groundwater by snowmelt (rainfall), resulting in a significant rise in groundwater levels within a short time. The calculated and simulated snowmelt (rainfall) infiltration coefficient revealed that during the spring snowmelt period, the recharge capacity of snowmelt or rainfall to groundwater at the site is 3.2 times during the stable thawing period and 4.5 times during the non-freezing period. [ABSTRACT FROM AUTHOR]

Land use changes inevitably lead to changes in the carbon stocks stored in the soil. However, despite numerous studies investigating soil organic carbon (SOC) dynamics following the afforestation of post-agricultural lands, findings remain diverse and often inconclusive. In this study, the effect of stand age on the carbon content and stock in Scots pine (Pinus sylvestris) stands located in the Dfb-climate zone was investigated. Five research plots, characterized by similar soil types, geological structures, and tree cover, but differing in stand age (14-, 27-, 37-, 55-, 90-year-old stands), were selected. Additionally, one plot was located at arable soil as a reference. The soil was sampled from both organic and mineral horizons. The content of organic carbon in the organic horizion increased with years that passed from afforestation and amounted to 234.0, 251.6, 255.0, 265.0 and 293.0 g·kg−1 in 14-, 27-, 37-, 55- and 90-year-old stands, respectively. Such a pattern was also observed in the upper mineral horizons where the contents of SOC gradually increased from 7.27 g·kg−1 up to 17.1 g·kg−1. In the organic horizon, the stock of OC increased significantly with stand age up to 55 years after afforestation, while in the former plough layer, SOC stocks were found to slowly increase with stand age. The afforested soils, with the organic horizon, reached levels of carbon stocks observed on arable land after 17 years. Notably, the SOC stock in the mineral A horizon reach this level after 83 years. The obtained results indicate that in the years immediately following afforestation, SOC content is notably higher in arable soils compared to forest soils. However, as stand age increases, the SOC contents of upper horizons in forest soils surpass those of comparable agricultural soils. The observed SOC variability pinpoints the necessity of long-term monitoring in forest ecosystems in order to better understand the temporal dynamics of carbon turnover and to optimize afforestation strategies for long-term carbon sequestration. [ABSTRACT FROM AUTHOR]

Flooded rice cultivation, accounting for 75% of global rice production, significantly influences soil redox potential, element speciation, pH, and nutrient availability, presenting challenges such as extensive water usage and altered soil properties. This study investigates bacterial community dynamics in rice soils subjected to repeated draining and flooding in Rio Grande do Sul, Brazil. We demonstrate that bacterial communities exhibit remarkable resilience (the capacity to recover after being altered by a disturbance) but cannot remain stable after long-term exposure to environmental changes. The beta diversity analysis revealed four distinct community states after 11 draining/flooding cycles, indicating resilience over successive environment changes. However, the consistent environmental disturbance reduced microbial resilience, causing the bacterial community structure to shift over time. Those differences were driven by substitutions of taxa and functions and not by the loss of diversity. Notable shifts included a decline in Acidobacteria and an increase in Proteobacteria and Chloroflexi. Increased Verrucomicrobia abundance corresponded with lower pH levels. Functional predictions suggested dynamic metabolic responses, with increased nitrification during drained cycles and a surge in fermenters after the sixth cycle. Despite cyclic disturbances, bacterial communities exhibit resilience, contributing to stable ecosystem functioning in flooded rice soils. These findings enhance our understanding of microbial adaptation, providing insights into sustainable rice cultivation and soil management practices. [ABSTRACT FROM AUTHOR]

Background: Soil microorganisms play a key role in nutrient cycling, carbon sequestration, and other important ecosystem processes, yet their response to seasonal dry–wet alternation remains poorly understood. Here, we collected 120 soil samples from dry-hot valleys (DHVs, ~ 1100 m a.s.l.), transition (~ 2000 m a.s.l.) and alpine zones (~ 3000 m a.s.l.) along the Jinsha River in southwest China during both wet and dry seasons. Our aims were to investigate the bacterial microbiome across these zones, with a specific focus on the difference between wet and dry seasons. Results: Despite seasonal variations, bacterial communities in DHVs exhibit resilience, maintaining consistent community richness, diversity, and coverage. This suggests that the microbes inhabiting DHVs have evolved adaptive mechanisms to withstand the extreme dry and hot conditions. In addition, we observed season-specific microbial clades in all sampling areas, highlighting their resilience to environmental fluctuations. Notably, we found similarities in microbial clades between soils from DHVs and the transition zones, including the phyla Actinomycetota, Chloroflexota, and Pseudomonadota. The neutral community model respectively explained a substantial proportion of the community variation in DHVs (87.7%), transition (81.4%) and alpine zones (81%), indicating that those were predominantly driven by stochastic processes. Our results showed that migration rates were higher in the dry season than in the wet season in both DHVs and the alpine zones, suggesting fewer diffusion constraints. However, this trend was reversed in the transition zones. Conclusions: Our findings contribute to a better understanding of how the soil microbiome responds to seasonal dry–wet alternation in the Jinsha River valley. These insights can be valuable for optimizing soil health and enhancing ecosystem resilience, particularly in dry-hot valleys, in the context of climate change. [ABSTRACT FROM AUTHOR]

Chromolaena odorata is a noxious alien invasive weed species with an enormous impact on the terrestrial ecosystem. The allelopathic potentials of this weed have had little attention, leading to changes in soil properties and microbial communities. This study investigates the impacts of Chromolaena odorata invasion gradients on rhizospheric soil chemical properties and microbial response in the Mount Cameroon Region. Forty-eight soil samples at four different degrees of invasion (uninvaded, low degree invasion, moderate degree invasion and high degree invasion) based on species coverage within subplots in four study areas were collected and rhizospheric soil chemical properties, microbial load, phosphatases activities and secondary metabolites were evaluated. At medium-degree invasion, rhizospheric soil concentrations of P, K and Fe increased with arbuscular mycorrhizal fungi (AMF) colonization and phosphatases enzyme activities. Soil C, N and organic matter were significantly increased at high-degree invasion, supporting the use of the plant as a fallow crop. Acid phosphatase activity ranged from 0.69 to 0.90 mmol h-1 kg-1 and was significantly different at different degrees of invasion. AMF colonization ranged from 23.33 to 50.00%, with a strong positive correlation between AMF colonization and phosphatase activity. Soil bacterial load was high (46 × 105 CFU/g– 67 × 105 CFU/g), with mostly Staphylococcus having health concerns about its spread. The invasion situation had no significant effect on soil bacterial load, but high-degree invasion significantly increased fungal load. Low-degree invaded soils had high saponin (24.55±0.00 mg/g), flavonoid (47.7 mg/g) and tannin (28.68 mg/g) concentrations. The investigation reveals that Chromolaena odorata invasion altered rhizospheric soil properties and microbial communities significantly, thereby influencing ecosystem dynamics and soil nutrient availability. However, further studies elucidating kinds of secondary metabolites, identifying microbial communities, and monitoring soil changes influenced by C. odorata are essential for effective ecosystem management. [ABSTRACT FROM AUTHOR]

In response to the degraded soil health and lack of improvement in the yield of rice–wheat cropping systems in South Asia's Indo-Gangetic Plains, an experiment was formulated in a split-plot design. Four rice residue management practices were the primary factor, alongside two nitrogen levels (150 and 180 kg/ha) and two nitrogen split levels (two and three splits) as sub-treatments. The findings revealed a notable increase in soil organic carbon (SOC), microbial count, and enzymatic activity in plots subjected to conservation tillage and residue treatment compared to those in plots subjected to partial residue (anchored stubbles) and conventional methods (residue incorporated with chopping). The collective analysis demonstrated a significant influence of rice residue management practices and nitrogen application levels on wheat yield attributes and productivity. Specifically, zero tillage with full residue (unchopped) in wheat exhibited a 5.23% increase in grain yield compared to conventional tillage with full residue (chopped), concurrently boosting the soil microbial count by 19.80–25%, the diazotrophic count by 29.43–31.6%, and the actinomycete count by 20.15–32.99% compared with conventional tillage. Moreover, applying nitrogen in three splits (at sowing, before the 1st irrigation, and after the 1st irrigation) led to a 6.25% increase in grain yield than that in two splits (at sowing and after the 1st irrigation), significantly impacting wheat productivity in the soil. Furthermore, the zero tillage-happy seeder with full residue elevated dehydrogenase activity from 77.94 to 88.32 μg TPF/g soil/24 h during the study year, surpassing that in the conventional plot. This increase in enzymatic activity was paralleled by a robust positive correlation between the microbial population and enzymatic activity across various residue retention practices. In conclusion, the results underscore the efficacy of crop residue retention following conservation tillage, in tandem with nitrogen optimization and scheduling, in enhancing wheat yield within the rice–wheat cropping system. [ABSTRACT FROM AUTHOR]

Soil erosion is one of the main issues that endangers global ecosystems. This study explored the spatiotemporal distribution of soil erosion and its drivers in the karst plateau mountainous region. A detailed examination of topography, soil, vegetation, land use, and precipitation data from 2000 to 2020 was conducted in Bijie City using the revised universal soil loss equation model. We also explored the driving forces using a geographical detector. The findings show that between 2000 and 2020, soil erosion first decreased, followed by an increase. The southwest, south, and northern regions contained the highest intensity of soil erosion. Land use, slope, and precipitation are the primary factors influencing soil erosion, with slopes having the greatest impact. By improving our understanding of the dynamics of soil erosion and the primary variables that influence it in karst plateau mountainous environments, our findings can assist in the development of strategies and technical support for sustainable soil and water conservation. [ABSTRACT FROM AUTHOR]

Current understanding of soil carbon dynamics suggests that plant litter quality and soil mineralogy control the formation of mineral-associated soil organic carbon (SOC). Due to more efficient microbial anabolism, high-quality litter may produce more microbial residues for stabilisation on mineral surfaces. To test these fundamental concepts, we manipulate soil mineralogy using pristine minerals, characterise microbial communities and use stable isotopes to measure decomposition of low- and high-quality litter and mineral stabilisation of litter-C. We find that high-quality litter leads to less (not more) efficient formation of mineral-associated SOC due to soil microbial community shifts which lower carbon use efficiency. Low-quality litter enhances loss of pre-existing SOC resulting in no effect of litter quality on total mineral-associated SOC. However, mineral-associated SOC formation is primarily controlled by soil mineralogy. These findings refute the hypothesis that high-quality plant litters form mineral-associated SOC most efficiently and advance our understanding of how mineralogy and litter-microbial interactions regulate SOC formation. This study challenges the hypothesis that high-quality plant litters form stable, mineral-associated soil organic carbon most efficiently, providing evidence that litter-microbial interactions and soil mineralogy regulate soil organic carbon formation. [ABSTRACT FROM AUTHOR]

Soil moisture is a key variable affecting agricultural production and ecological environment. It is therefore of great significance to acquire accurate spatial distribution information of soil moisture. Compare to conventional point-scale based measurements, the Cosmic Ray Neutron Probe (CRNP) provides an alternative approach for capturing soil moisture dynamics to address drought monitoring, plant water stress detection, as well as various hydrological applications. CRNP can realize continuous observation of soil moisture at the field scale and estimate average soil water content with a 0.1–0.2 km² quasicircular footprint by monitoring the neutron intensity near the ground. However, previous studies conducted soil moisture observation using CRNP are often limited to a single landscape, its ability to observe soil moisture in different geographical environments and vegetation cover types still needs to be further understood. In this study, data from 16 representative stations located in different climatic zones and under different vegetation cover conditions worldwide were selected, including seven grasslands covered stations, three farmlands covered stations, three forests covered stations and three shrubs covered stations, and a unified data processing procedure and soil moisture estimation method were used to invert the average soil moisture observation value in the observation area. The environmental factors affecting the neutron data were corrected, including atmospheric pressure correction, air humidity correction, incident neutron intensity correction and aboveground biomass correction to remove their influence to neutron counts. The N0 parameter method was used to invert the soil water value. Ground point-scale based soil moisture measurements within the CRNP footprint were aggregated to validate the soil moisture estimates based on CRNP observations. Therefore, a systematic and comprehensive comparison of soil moisture observation capabilities of CRNP over different climatic zones and vegetation cover conditions can be performed. The results indicate that, in general, CRNP observations under different vegetation covers and vegetation cover conditions were highly sensitive to soil water dynamics and can clearly respond to precipitation events. However, there were significant differences in the estimation accuracies. CRNP outperforms over grasslands, except result of one station was relatively poor, the other stations showed high reliability,, with the optimal RMSE of 0.05 cm³/cm³, the optimal ubRMSE of 0.03 cm³/cm³, the optimal Bias of 0.006 cm³/cm³, and the optimal R² of 0.88. In shrub covered areas, the CRNP observation effect of selected sites was strongly affected by the local environment, and the accuracy of soil water estimation is quite different. In was shown R² value varies greatly, from 0.91 at the best to 0.02 at the worst, while ubRMSE, RMSE and Bias are repectively of 0.01 cm³/cm³, 0.02 cm³/cm³, and -0.02 cm³/cm³ at the best condition. In terms of the CRNP sites under grassland cover, the differences in CRNP observations are mainly related to the growth of surface vegetation, etc.; at sites under crop cover, the differences in CRNP observations are mainly related to anthropogenic activities in the agricultural areas and surface heterogeneity; at sites under forest cover, the differences are mainly related to the high canopy, etc. With repsect to the sites under shrub cover, the differences are mainly related to climate, etc. The Yanco and Sidaoqiao sites have the worst observational accuracy among all the sites, with an R² of only 0.46 at Yanco and 0.02 at Sidaoqiao, which have weak data consistency may be mainly related to special local soil moisture environments. In conclusion, CRNP observations of soil moisture are more likely to capture regional moisture fluctuations than point-scale in situ observations. This study helps us better understand the capabilities and potentials of CRNP in observing soil moisture, and provide a scientific basis and reference for applying CRNP observation to capture the spatio-temporal changes of soil water at field scale under different vegetation cover and climate conditions. [ABSTRACT FROM AUTHOR]

Developing a functional linkage between hydrological variables and easily accessible terrain and soil information is a novel concept for distributed hydrological models. This approach aims to address limitations imposed by data scarcity and high computational demands. The model hypothesizes that the relationship between the evaporation flux and the absolute value of the matric potential follows a power exponential pattern. Analytic solutions for the groundwater depth, the evaporation capacity, and the storage capacity are derived with respect to the topographic index, considering the relationship between the groundwater depth and the topographic index and the influence of setting off. Subsequently, a distributed Xin'anjiang Model using the analytic solution of the storage capacity under unsteady-state conditions is constructed. This new model is employed to simulate soil moisture and discharge in the Tarrawarra Watershed. The simulation results for soil moisture and discharge are compared with those from the Storage Capacity Model and the DHSVM. Additionally, the computational speeds of all three models are compared. The findings indicate that the simulation accuracy of the new model for soil moisture and discharge surpasses that of the Storage Capacity Model and the DHSVM. Meanwhile, the computational speed of the new model is significantly faster than the DHSVM and slightly slower than the Storage Capacity Model. It offers a balance between computational efficiency, predictive accuracy, and physical mechanism representation. The data requirements of the new model are minimal and easy to procure, and it requires less computational effort. Moreover, it accurately captures the spatial and temporal dynamics of soil moisture and the discharge process of the watershed. [ABSTRACT FROM AUTHOR]

Biological equilibrium has been disturbed by significant land use changes in recent years in the Eastern Ghats of India, which has worsened soil quality and compromised vital ecosystem services. To determine the effect of changes in land use on the balance of soil carbon, this study was carried out in Kolli hills, a portion of the Eastern Ghats that includes six distinct ecosystems: evergreen forest (EF), deciduous forest (DF), thorn forest (TF), agricultural system (AS), horticultural system (HS), and plantation system (PS). Soil from 40 sites each within six ecosystems at two depths were collected to give a total of 480 soil samples, and the samples were analyzed. The results showed that soil organic carbon, carbon stock, microbial biomass carbon, and microbial biomass nitrogen were more significant in EF > DF > TF and lower in AS. The observed carbon stocks in EF, DF, and TF were 179.96, 146.80 and 128.99 t ha−1, respectively, at 15 cm and decreased at 30 cm. Among the carbon pools, the water-soluble, less labile, very labile, non-labile, labile, and particulate organic carbon were greater in EF and lower in AS. The EF had higher soil microbial biomass, carbon, nitrogen, and dehydrogenase enzyme activity levels than the DF and TF. Finally, it is determined that AS, HS, and PS must immediately implement carbon management measure to restore productivity and ecosystem function. [ABSTRACT FROM AUTHOR]

The formation of mineral-associated organic matter (MAOM) is a key phenomenon that may explain the slow turnover rates of carbon in soil organic matter (SOM). Despite this, important details pertaining to the structure and dynamics of MAOM remain unknown. In the present study, we use replica-exchange molecular dynamics simulations to gain insight into the structure of MAOM on the surface of prototypical phyllosilicate clay and Fe-oxide minerals, montmorillonite and goethite, fine-grained minerals that strongly impact soil carbon dynamics in temperate and tropical regions, respectively. We examine the impact of aqueous chemistry through the presence of either Na+ or Ca2+ charge balancing counterions. Our results are consistent with the hypothesized multilayer sorption ("onion-skin") model of MAOM and help to explain previous observations regarding the patchy distribution of SOM on mineral surfaces. In particular, the SOM coatings are partial and laterally heterogeneous, and water retains extensive access to mineral surfaces even when significant SOM sorption occurs. Low molecular weight neutralSOMmolecules (<200 Da) infrequently interact with the mineral surfaces nor their sorbed organic matter coatings and are increasingly labile with decreasing molecular weight. This observation is inconsistent with a central feature of the predominant soil continuum model of SOM and suggests that further iterations of the conceptual model may be required. [ABSTRACT FROM AUTHOR]

The impact of microplastics on antibiotic resistance has attracted widespread attention. However, previous studies primarily focused on the effects of individual microplastics. In reality, diverse microplastic types accumulate in soil, and it remains less well studied whether microplastic diversity (i.e., variations in color, shape or polymer type) can be an important driver of increased antibiotic resistance gene (ARG) abundance. Here, we employed microcosm studies to investigate the effects of microplastic diversity on soil ARG dynamics through metagenomic analysis. Additionally, we evaluated the associated potential health risks by profiling virulence factor genes (VFGs) and mobile genetic elements (MGEs). Our findings reveal that as microplastic diversity increases, there is a corresponding rise in the abundance of soil ARGs, VFGs and MGEs. We further identified microbial adaptive strategies involving genes (changed genetic diversity), community (increased specific microbes), and functions (enriched metabolic pathways) that correlate with increased ARG abundance and may thus contribute to ARG dissemination. Additional global change factors, including fungicide application and plant diversity reduction, also contributed to elevated ARG abundance. Our findings suggest that, in addition to considering contamination levels, it is crucial to monitor microplastic diversity in ecosystems due to their potential role in driving the dissemination of antibiotic resistance through multiple pathways. The effects of microplastics (MPs) on soil microbial communities and antimicrobial resistance genes are not well understood. Here, the authors used microcosm studies to show that MP diversity, and partially fungicide treatment and reduced plant diversity, correlate with higher levels of ARG and related genetic factors. [ABSTRACT FROM AUTHOR]

Background: The extent of natural salt-laden groundwaters used for irrigation is increasing worldwide, which is a fast-emerging threat to agroecosystems and global food security. The salt buildup in the soil is linked to deteriorated soil chemical, physical, and biological health and decreased land productivity. Alkali waters with high residual sodium carbonate (RSC) is one of the severe poor-quality waters that deteriorate soil. We evaluated soil microbial dynamics and soil health at critical growth stages of rice crop receiving two-decade-long irrigation with three levels of alkali water and two reclamation strategies. These included good-quality water (GQW), alkali water (ALKW) with an RSC concentration of 5 me L⁻1 (ALKW1), ALKW with an RSC concentration of 10 me L⁻1 (ALKW2), ALKW2 treated to neutralize RSC to 5 me L⁻1 using gypsum (CaSO4·2H2O; ALKW2 + GYP), and ALKW2 treated with sulfuric acid (H2SO4; ALKW2 + SA). Eleven microbial parameters were used to develop a soil microbial activity index (SMAI), and eight soil health indicators were correlated with changes in SMAI and crop productivity. Results: The SMAI peaked under good-quality water (GQW) conditions (0.84–0.89), while the lowest values were recorded under ALKW2 (0.06–0.18). Neutralized alkali waters, ALKW2 + SA and ALKW2 + GYP, significantly improved SMAI with corresponding values of 0.25–0.35 and 0.13–0.32, respectively. SMAI across all stages correlated positively (R2 = 0.91–0.98) with rice yield. Microbial activity varied with the crop growth stage, peaking at tillering. Gypsum application alone, aimed at neutralizing alkalinity from an RSC of 10 to 5 me L⁻1, proved insufficient in bringing the SMAI up to the ALKW1 (RSC level of 5 me L⁻1). Conclusions: The application of dilute sulfuric acid demonstrated better results in restoring the soil microbial activity index than gypsum amendment; however, sulfuric acid treatment depends on native calcium carbonate (CaCO3) dissolution for its effectiveness. It may not suffice for soil stability improvement in the long term, especially when native CaCO3 is low. Therefore, integrating gypsum and dilute sulfuric acid for RSC neutralization is worthwhile; however, further assessment is needed to confirm their combined impact on soil biochemical and physical properties. [ABSTRACT FROM AUTHOR]

Bacterivorous nematodes are important grazers in the soil micro‐food web. Their trophic regulation shapes the composition and ecosystem services of the soil microbiome, but the underlying population dynamics of bacteria and archaea are poorly understood. We followed soil respiration and 221 dominant bacterial and archaeal 16S rRNA gene amplicon sequencing variants (ASVs) in response to top‐down control by a common bacterivorous soil nematode, Acrobeloides buetschlii, bottom‐up control by maize litter amendment and their combination over 32 days. Maize litter amendment significantly increased soil respiration, while A. buetschlii addition caused an earlier peak in soil respiration. Underlying bacterial and archaeal population dynamics separated into five major response types, differentiating in their temporal abundance maxima and minima. In‐depth analysis of these population dynamics identified a broad imprint of A. buetschlii grazing on dominant bacterial (Acidobacteriota, Bacteroidota, Gemmatimonadota, Pseudomonadota) and archaeal (Nitrososphaerota) ASVs. Combined bottom‐up control by maize litter and top‐down control by A. buetschlii grazing caused a succession of soil microbiota, driven by population changes first in the Bacteroidota, then in the Pseudomonadota and finally in the Acidobacteriota and Nitrososphaerota. Our results are an essential step forward in understanding trophic modulation of soil microbiota and its feedback on soil respiration. [ABSTRACT FROM AUTHOR]

Drought, a significant calamity in the natural domain, has extensive worldwide repercussions. Drought, primarily characterized by reduced soil moisture (SM), presents a significant risk to both the world environment and human existence. Various drought indicators have been suggested to accurately represent the changing pattern of SM. The study examines various indices related to the Drought Severity Index (DSI), Evaporation Stress Index(ESI), Vegetation Supply Water Index(VSWI), Temperature-Vegetation Dryness Index(TVDI), Temperature Vegetation Precipitation Dryness Index(TVPDI), Vegetation Health Index(VHI), and Temperature Condition Index (TCI). An evaluation was conducted to assess the effectiveness of seven drought indicators, such as DSI, ESI, TVPDI, VSWI, etc., in capturing the changes in SM in Mu Us Sandy Land. The research results indicated that DSI and ESI had the highest accuracy, while TVDI and VSWI showed relatively lower accuracy. However, their smaller fluctuations in the time series demonstrated stronger adaptability to different regions. Additionally, the delayed impact of aridity indices on soil moisture, variable attributes, temperature, and vegetation coverage in sandy land and grassland areas with low, medium, and high coverage all contributed to the effectiveness of the four aridity indices (DSI, ESI, VSWI, and TVPDI) in capturing the dynamics of soil moisture. The primary element that affects the effectiveness of TVDI is the divergence of the relationship curve between Land Surface Temperature (LST) and Normalized Difference Vegetation Index (NDVI), which is a kind of deterioration. This paper presents a very efficient approach for monitoring soil moisture dynamics in dry and semi-arid regions. It also analyzes the patterns of soil moisture changes, offering valuable scientific insights for environmental monitoring and ecological enhancement. [ABSTRACT FROM AUTHOR]

Data transformation of the reference soil organic matter (SOM) decomposition rates (kref), often derived as turnover times or in alternative formats, is commonly used to develop ecological models for projecting the persistence of SOM. However, the effects of reciprocal or logarithmic transformation of kref on model performance and edaphic‐climatic patterns remain uncertain. Here, we convert published kref values into reciprocal or logarithmic formats and establish machine learning models between the transformed kref and edaphic‐climatic predictors. We show that models trained with the transformed kref exhibit a 11.6%−68.4% reduction in performance upon re‐conversion to kref compared to those trained with the original kref. The variable importance analysis identifies distinct key predictors governing the original kref and its transformed counterparts. This suggests that data transformation alters the relative significance of predictors without necessarily improving kref prediction performance. Consequently, our study underscores the importance of directly focusing on the original values rather than alternative representations when dissecting a given variable's patterns and mechanisms in ecological modeling. Core Ideas: Data transformation caused reduced predictive performance upon re‐conversion to kref compared to the original kref.Models trained with data transformation exhibited divergent edaphic‐climatic controls for different formatted kref.This study underscores the importance of directly focusing on original values rather than alternative representations. Plain Language Summary: The first‐order model is commonly used to simulate the dynamics of soil organic matter decomposition. The reference decomposition rates (kref) in the first‐order model are usually transformed into reciprocal or logarithmic formats, which may affect model performance as well as the regulatory patterns of edaphic‐climatic factors. In this study, we investigated the effects of data transformation on predictive performance and variable importance. We found that models trained with transformed kref exhibited reduced performance upon re‐conversion to kref, compared to those trained with the original kref. In addition, data transformation altered the distribution and range of the dependent variable, leading to divergent controlling roles of explanatory variables pertaining to models trained with different formatted kref. Our study underscores the need to apply models directly to the original variables rather than their transformed representations. [ABSTRACT FROM AUTHOR]

Wildfire is a disturbance expected to increase in frequency and severity, changes that may impact carbon (C) dynamics in the soil ecosystem. Fire changes the types of C sources available to soil microbes, increasing pyrogenic C and coarse downed wood, and if there is substantial tree mortality, decreasing C from root exudates and leaf litter. To investigate the impact of this shift in the composition of C resources on microbial processes driving C cycling, we examined microbial activity in soil sampled from an Oregon burn 1 year after fire from sites spanning a range in soil burn severity from unburned to highly burned. We found evidence that postfire rhizosphere priming loss may reduce soil C loss after fire. We measured the potential activity of C‐acquiring and nitrogen (N)‐acquiring extracellular enzymes and contextualized the microbial resource demand using measurements of mineralizable C and N. Subsurface mineralizable C and N were unaltered by fire and negatively correlated with hydrolytic extracellular enzyme activity (EEA) in unburned, but not burned sites. EEA was lower in burned sites by up to 46%, but only at depths below 5 cm, and with greater decreases in sites with high soil burn severity. These results are consistent with a subsurface mechanism driven by tree mortality. We infer that in sites with high tree mortality, subsurface EEAs decreased due to loss of rhizosphere priming and that inputs of dead roots contributed to mineralizable C stabilization. Core Ideas: Postfire extracellular enzyme activity decreases were observed only in sub‐soils of higher burn severity sites.In high tree mortality burns, loss of rhizosphere priming may slow decomposition and mitigate carbon loss.This work challenges conventional views that fire affects only the surface of soils via direct heat and combustion. Plain Language Summary: Wildfires are expected to become more severe and frequent, which may change how much carbon is stored in the soil. Fire changes the relative amount of leaves, wood, and charcoal available for soil microbes to decompose, which may affect soil microbial activity and soil carbon as a result. In this study, we evaluated the effect of fire on soil microbial decomposition activity. We found burned areas had less microbial decomposition activity than unburned areas, but only below soil depths of 5 cm in areas where most trees died after the fire. This was a surprising result because fire heat and combustion only directly affects the surface soil. We attribute the lower activity in higher burn severity subsurface soils to greater dead roots and a loss of root secretions, which are known to boost decomposition. Reduced decomposition could partly offset fire‐caused carbon loss from the ecosystem. More research is needed to clarify the long‐term effect on soil carbon. [ABSTRACT FROM AUTHOR]

Based on a soil analysis of individual crops, lower nitrogen (N) inputs may affect soil fertility and the soil's capacity for carbon sequestration. This study investigates the changes in soil nitrogen levels, the amounts of labile and recalcitrant carbon fractions, and their relationship to soil organic carbon (SOC) over the course of a single crop season. We conducted this study on seven crops in the provinces of Chiang Mai, Lamphun, and Lampang in northern Thailand, from February 2022 to December 2023. The farmer plots, which included litchi, mango, banana, maize, cabbage, garlic, and paddy rice, underwent three nitrogen addition treatments: high-nitrogen fertilizer (FP), reduced-nitrogen fertilizer informed via soil analysis (FS), and fertilizer absence (FZ). Soil samples were collected from a depth of 0 to 30 cm following the harvest of each crop. Subsequently, we utilized these samples to distinguish between labile and recalcitrant carbon fractions and assessed the impact of reduction through a one-way ANOVA. This study indicated a reduced availability of nitrogen, with the recalcitrant carbon fractions being the fine fraction (FF) and less labile carbon (LLB_C). The labile organic carbon fraction, referred to as LB_C, exhibited no change in FP treatment, in contrast to the non-fine fraction (NFF) and permanganate-oxidizable carbon (POXC). Our concern was to reduce the quantity of synthetic nitrogen fertilizer to achieve a lower level of soil organic carbon (SOC) and decreased nitrogen availability. These findings underscore the importance of considering N management when assessing soil carbon dynamics in agricultural soils, and, in future work, we should therefore model the optimal N input for crop yield, soil fertility, and soil carbon storage. [ABSTRACT FROM AUTHOR]

The purpose of this study was to identify the optimal smash-ridging tillage depth in sugarcane fields in Guangxi, China, in order to improve soil moisture conditions. Three treatments were implemented in sugarcane cultivation areas, with smash-ridging tillage depths of 20 cm, 40 cm, and 60 cm. The dynamics of soil moisture were monitored at depths of 5 cm, 20 cm, and 40 cm to investigate their response to precipitation. The results indicated that the F40 treatment had the highest mean soil moisture content. The F40 treatment exhibited a 29.85% increase in percent area of significant coherence (PASC) compared to the F20 treatment and an 8.23% increase in PASC compared to the F60 treatment. These results indicated that the F40 treatment exhibited the most significant vertical exchange. Under the same precipitation conditions, the F20 and F40 treatments exhibited a quicker soil moisture response to precipitation than the F60 treatment. The mean soil moisture replenishment (SMR) of the F40 treatment was 0.94% and 11.02% higher than that of the F20 and F60 treatments, respectively. Following the torrential rainfall event, the F40 treatment exhibited the slowest recession rate of soil moisture, indicating a greater capacity for water retention. Therefore, the smash-ridging tillage depth of 40 cm resulting in the best responsiveness to precipitation was recommended for sugarcane cultivation in Guangxi, China, which effectively improved soil moisture exchanges. [ABSTRACT FROM AUTHOR]