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In recent years, machine learning (ML) algorithms have gained substantial recognition for ecological modeling across various temporal and spatial scales. However, little evaluation has been conducted for the prediction of soil organic carbon (SOC) on small data sets commonly inherent to long-term soil ecological research. In this context, the performance of ML algorithms for SOC prediction has never been tested against traditional process-based modeling approaches. Here, we compare ML algorithms, calibrated and uncalibrated process-based models as well as multiple ensembles on their performance in predicting SOC using data from five long-term experimental sites (comprising 256 independent data points) in Austria. Using all available data, the ML-based approaches using Random forest and Support vector machines with a polynomial kernel were superior to all process-based models. However, the ML algorithms performed similar or worse when the number of training samples was reduced or when a leave-one-site-out cross validation was applied. This emphasizes that the performance of ML algorithms is strongly dependent on the data-size related quality of learning information following the well-known curse of dimensionality phenomenon, while the accuracy of process-based models significantly relies on proper calibration and combination of different modeling approaches. Our study thus suggests a superiority of ML-based SOC prediction at scales where larger datasets are available, while process-based models are superior tools when targeting the exploration of underlying biophysical and biochemical mechanisms of SOC dynamics in soils. Therefore, we recommend applying ensembles of ML algorithms with process-based models to combine advantages inherent to both approaches. • We evaluated process-based (PB) and machine-learning (ML) models for SOC prediction. • Random forest & support vector machine predicted SOC superior to PB models. • Reduced data availability and quality significantly weakened ML model performance. • ML-assisted PB model ensembles strongly improved model performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Anaerobic digestates were produced at different HRT-OLR for a fixed feedstock type. • Biochemical fractionation on C and N was combined with soil incubation tests. • Increasing the HRT varied the profiles of C mineralization in soils. • The tested HRT-OLR had reduced impact on the distribution of particulate C and N. • Substrates were transformed into fast-acting fertilizers due to anaerobic co-digestion. The growing use of anaerobic co-digestion (AcoD) in processing organic waste has led to a significant digestate production. To effectively recycle digestate back into soils, it is crucial to understand how operational variables in the AcoD process influence the conversion of organic matter (OM). To address this, a combination of biochemical fractionation and various soil incubation tests were employed to assess the stability of OM in digestates generated from anaerobic continuous reactors fed with a food waste-hay mixture and operating at different hydraulic retention times (HRT) and organic loading rates (OLR). This study revealed that digester performance and operating parameters impacted carbon dynamics in soils. A decrease in the carbon mineralization in soils when increasing the HRT was reported (48 ± 4 % for 70 days compared to 59 ± 1 % for 42 days). Specific HRT and OLR values were found to be linked to carbon accessibility and complexity, confirming that longer HRT lead to higher OM removal and increased complexity in soluble OM, despite minor discrepancies in relative carbon distribution. Furthermore, comparable rates of nitrogen mineralization in soils were observed for all digestates, consistent with the accessibility of nitrogen from the particulate OM. Nevertheless, AcoD converted substrates with the potential to immobilize nitrogen in soils into fast-acting fertilizers. In summary, this study underscores the importance of controlling the AcoD performances to evaluate the suitability of digestates for sustainable agricultural practices. [ABSTRACT FROM AUTHOR]

• Directions for future research of sustainable use of biosolids as a N source. • Global biosolids regulations and common biosolids treatment methods are discussed. • Higher total N content in HDB and reduced N availability from CB are reported. • Key factors in biosolids treatment affecting biosolids properties are identified. • Existing models of soil N dynamics after biosolids application are summarized. Application of biosolids to agricultural land has gained increasing attention due to their rich nutrient content. There are a variety of treatment processes for converting sewage sludge to biosolids. Different treatment processes can change the physicochemical properties of the raw sewage sludge and affect the dynamics of nutrient release in biosolids-amended soils. This paper reviews heat drying, alkaline treatment, and composting as biosolids treatment processes and discusses the effects of these treatments on biosolid nitrogen (N) content and availability. Most N in the biosolids remain in organic forms, regardless of biosolids treatment type but considerable variation exists in the mean values of total N and mineralizable N across different types of biosolids. The highest mean total N content was recorded in heat-dried biosolids (HDB) (4.92%), followed by composted biosolids (CB) (2.25%) and alkaline-treated biosolids (ATB) (2.14%). The mean mineralizable N value was similar between HDB and ATB, with a broader range of mineralizable N in ATB. The lowest N availability was observed in CB. Although many models have been extensively studied for predicting potential N mineralization in soils amended with organic amendments, limited research has attempted to model soil N mineralization following biosolids application. With biosolids being a popular, economical, and eco-friendly alternative to chemical N-fertilizers, understanding biosolids treatment effects on biosolids properties is important for developing a sound biosolids management system. Moreover, modeling N mineralization in biosolids-amended soils is essential for the adoption of sustainable farming practices that maximize the agronomic value of all types of biosolids. [ABSTRACT FROM AUTHOR]

• Governing equations of the beam are established by euler-bernoulli and dynamic unsaturated soil theories. • Equivalent stiffness of the subgrade is obtained in transformed domain based on compatibility conditions. • Solution of the beam-subgrade system is acquired by introducing the inverse fourier transform. • Performance of the beam on unsaturated subgrade due to moving load and the variation of saturation is evaluated. Performance evaluation of the beam subject to the variation of saturation change of the subgrade is of significance to the optimal design of the high speed railway (HSR). This study proposes a mathematical modelling to describe the dynamic interaction between a beam and a layered transversely isotropic unsaturated subgrade. Based on the Euler-Bernoulli theory and the dynamic unsaturated soil theory, governing equations of this mathematical model are established. With the aid of the precise integration method, Fourier transform and compatibility conditions, the equivalent stiffness of the subgrade is obtained in the transformed domain. Introducing the equivalent stiffness into the beam motion equation, the dynamic solution of the beam-subgrade system is acquired by further introducing the inverse Fourier transform. After verifying the correctness of this theory, a series of numerical examples are provided to discuss the parametric sensitivity. [ABSTRACT FROM AUTHOR]

• Macroscopic assessment via image analysis aimed to explore environmental trace evidence dynamics. • Transfer and persistence of soils to footwear and diatomaceous earth to clothing was tested. • Both environmental traces were retained and visually identifiable during one week of wear. • Soil type, clothing type, & body positioning significantly impacted persistence and distribution. • Recognising the presence of trace evidence is a critical first step in the forensic process. Environmental trace evidence offers useful circumstantial intelligence to link persons and scenes of forensic interest. An increasing empirical research base is dedicated towards understanding the transfer and persistence dynamics of environmental indicators including pollen, soils, and diatoms, within a diverse range of experimental frameworks. This paper presents two discrete studies exploring transfer and persistence of soils and sediments on footwear and diatomaceous earth adhered to clothing in forensically pertinent scenarios. Variables including sediment type, foot position, clothing type, and body positioning were also explored throughout. Both experiments incorporated a field-based methodology during the sampling effort. Photographs were collected of an initial transfer sample and of a retained assemblage following hours, days, and up to one-week of wear, facilitating macroscopic assessment of trace evidence dynamics. All images were processed using accessible, open-source software before spatial analysis of evidence distribution within and temporal assessment (% retention) upon each evidential surface. The results highlighted consistent loss of transferred sediment from footwear with significantly greater retention of loamy clay soil than dune sand which was absent beyond 24 h of wear. Loss was not influenced by wearer gait but was more rapid from those areas of the shoe sole in direct contact with the ground. Diatomaceous earth was retrieved from all three clothing types tested after one week – significant losses of material occurred before 48 h with a consistent assemblage identified beyond this. Denim was significantly more effective than acrylic and fleece for diatomaceous earth retention and significantly more material was lost from clothing worn on the lower body. These findings highlight the value of using visual environmental markers and a macroscopic analytical approach during the investigation of environmental trace dynamics. The methodology offers a novel, non-destructive assessment of soil and diatom transfer and persistence, complementing more extensive laboratory-based examinations to ensure the development of a well-rounded research base within the forensic sciences. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new model for exogenous organic matter in soil is developed. • Two digestate incubations in soil were conducted and used as calibration datasets. • The model simulates accurately the main processes observed in soil. As its use in agriculture grows, the fate of digestate in soil raises concerns on many different levels. In particular, the degradability of its organic matter when spread on soil is still an ongoing topic. In an effort to better understand the processes and dynamics of digestate soil incubation, C and N mineralization kinetics obtained in 358 days long laboratory incubations during decomposition of digestates were simulated using a dynamic model. The model includes twelve compartments related through processes including 18 parameters. The main novelty of this model is the use of accessibility-related variables to describe the fate of exogenous organic matter in soil, thus enabling a detailed understanding of its outcome in soil. Model calibration on cattle manure digestate incubation resulted in the estimation of parameter values. The newly calibrated model was then tested on an energy crop digestate incubation experiment. The model was able to reproduce accurately the experimental behavior of most variables. [ABSTRACT FROM AUTHOR]

Present study estimates seismic active earth pressure on the reinforced retaining wall by combining the lower bound finite element limit analysis and the modified Pseudo-dynamic method. A series of parametric analyses are performed by varying seismic acceleration coefficient, time period of seismic loading, soil friction and dilation angles, reinforcement spacing, length of reinforcement, soil-reinforcement interface, damping ratio of soil, soil-wall interface, wall inclination, and ground inclination. Maximum active earth pressure is exerted when natural time period of reinforced soil matches with the time period of an earthquake. Reinforcement is found to be effective in terms of reducing active earth pressure significantly on the wall subjected to seismic loading. Effectiveness of reinforcement depends upon two factors, namely vertical spacing and soil-reinforcement interface friction angle. For relatively smaller reinforcement spacing, soil-reinforcement behaves like a composite block, which helps to constraint stresses within a small area behind the wall. Maximum tensile resistance is developed when fully rough interface condition is assumed between soil and reinforcement layer. Failure patterns are provided to understand the behaviour of reinforced retaining wall under different time of seismic loading. • Without any presumption of failure surface geometry, present study predicts seismic active earth pressure on reinforced retaining wall. • Varying earthquake induced forces along wall height and its phase difference with time, soil damping ratio is considered. • Effectiveness of reinforcement in reducing active earth pressure depends on vertical spacing between reinforcements and soil-reinforcement interface. • Influences of soil parameters, soil-wall interface, ground and wall inclination are studied. • Maximum active earth pressure is exerted when natural time period of reinforced soil equals the time period of an earthquake. [ABSTRACT FROM AUTHOR]

The presence of non-biodegradable plastic waste is a serious concern for the health of endangered species. The present study is based on the sustainable utilisation of polyethylene terephthalate (PET) fibres obtained from waste plastic bottles to enhance the liquefaction resistance of fine sand. After performing a series of stress-controlled cyclic triaxial tests, the cyclic behaviour of PET-fibre reinforced sand has been investigated. The application of PET fibres was found to be more satisfactory in medium dense sand than that in loose sand as observed by residual excess pore water curves. In medium dense sand with 0.6% PET-fibres, the number of cycles to reach liquefaction was about 4 times that of the unreinforced sand. Using the dynamic shear modulus (G), the degradation index was calculated for both reinforced and unreinforced soils to assess stiffness characteristics. After nearly 50 loading cycles, the value of G / G max increased 2.55 times with the addition of 0.4% PET fibres in unreinforced sand. Based on the results obtained, a regression model has been developed for the calculation of number of liquefaction failure cycles (N cyc,L) in correlation with several parameters, namely, relative density (D r), fibre content (FC) and σ d /σ c ′ (σ d = deviator stress, σ c ′ = effective confining stress). • Liquefaction resistance of fine sand reinforced with polyethylene terephthalate (PET) fibres has been calculated. • Fibre content, relative density and deviator stress played a key role in affecting failure cycles. • Residual excess pore water pressure was evaluated to assess the plastic deformation during liquefaction. • Dynamic shear modulus and degradation index have been determined to assess stiffness characteristics. • Regression models have been developed to predict the number of failure cycles to attain a liquefaction state. [ABSTRACT FROM AUTHOR]

• Dynamic response of horizontal vibrating pile with different soil viscoelastic half-space types is presented. • An analytical solution considering the viscoelastic half-space of soil free-field under horizontal SV wave is established. • The similarities and differences among several foundation types are discussed based on the present analytical solution. An analytical solution has been developed to investigate the dynamic responses of floating pile with different soil viscoelastic half-space types. The dynamic response of a pile is governed by 1D vibration theory, in which the pile is assumed to be viscoelastic material with a circular cross-section and can be divided into two pile segments in a soil-air system. Meanwhile, the dynamic solution for soil is achieved by the application of the potential function decomposition and the variable separation method. Moreover, an analytical solution considering the viscoelastic half-space of the soil free-field under horizontal SV wave is established. Furthermore, the dynamic pile-soil interaction is established and solved efficiently through a precise theoretical derivation based on the displacement compatibility and traction equilibrium at the interface between the pile and soil. The present solution is compared with the substructure method and analytical solution with a rigid foundation to verify the rationality of the present analytical solution. Then, the similarities and differences among several foundation types are discussed based on the present analytical solution. The results have a certain guiding significance for engineering structures. [ABSTRACT FROM AUTHOR]

• A simplified approach to study the dynamic interaction between the pile group and two-layered soil under scour is presented. • The model is developed by combining the finite element method (FEM) and analytical layer element method (ALEM). • The effects of the scour type, scour depth, scour width and soil's layered property on the dynamic behavior of pile groups are examined. Pile groups for the bridge and jacket foundations in the marine or traffic geotechnical engineering are significantly influenced by the current scour in service. Under the effects of scour and dynamic load, the capability of the pile foundations to resist deformation is reduced and thus causes structural failure. This paper presents a FEM-ALEM coupling approach to study the dynamic interaction between a pile group and layered soils under scour condition. Behaviors of the pile group are analyzed by applying the finite element method. Fundamental solutions of the layered soils under scour condition are obtained by adopting the analytical layer element method. Comparisons with existing solutions are performed to confirm the correctness of the present approach, and numerical examples are provided to discuss the effects of the scour type, scour depth, scour width and layered property of soil on the dynamic behaviors of the pile group. The present coupling approach can be used to evaluate the responses of a pile group embedded in layered saturated soils under scour due to a vertical dynamic load. [ABSTRACT FROM AUTHOR]

• LoRaWAN Urban Green Space (UGS) sensing for stormwater management was demonstrated. • Soil moisture variations in UGSs and their contributing factors were investigated. • Rain amount and initial soil moisture dominate soil moisture response to rain. • UGS runoff coefficients were more dynamic than government guideline values. • Proactive drainage systems are needed for UGSs to handle extreme storm events. Monitoring urban green spaces (UGSs) is crucial for achieving sustainable urban development and ecological resilience. Leveraging LoRaWAN technology, a wireless environmental sensing system was developed and implemented to monitor soil moisture dynamics across seven diverse UGSs over a year. Analyses revealed notable variations in soil moisture influenced by vegetation types, soil conditions and physical settings. Seasonal trends indicated lower summer soil moisture in some UGSs resulting from increased evapotranspiration, while others maintained higher soil moisture due to more frequent irrigation. The soil moisture response to rainfall was quantitatively modeled, demonstrating the increase in soil moisture is highly positively dependent on rainfall amount and negatively dependent on initial moisture level. Both factors were significant (p <0.001) in most cases, and the models' adjusted R2 values were all above 0.65 except for one node. The findings also unveiled more dynamic ranges of UGS runoff coefficients than government guideline values, especially high runoff coefficients (0.4 to 1.0) for rainfall events above 50 mm. Therefore, although existing UGSs can help absorb smaller storms, proactive drainage systems are needed for UGSs to handle extreme events. The study highlights LoRaWAN's efficacy in urban environmental monitoring and provides valuable insights for managing and optimizing UGSs, especially in stormwater management. [Display omitted] [ABSTRACT FROM AUTHOR]

Plants affect soil microorganisms through the release of root exudates under pollution stress. This process may affect rhizosphere priming effect (RPE) and alter the rate of soil organic matter decomposition. However, the influence of plants on the decomposition of organic matter in soil subjected to pollution stress remains unclear. We studied the effects of exposure to perfluorooctanesulfonic (PFOS) and its alternative, chlorinated polyfluoroalkyl ether sulfonic (F-53B), at concentrations of 0.1 mg/kg and 50 mg/kg on the RPE of reed. We conducted our experiments in an artificial climate chamber and used the natural 13C tracer method to determine RPE. In the PFOS-exposed groups, the RPE was negative, with values of −11.45 mg C kg−1 soil d−1 in the low PFOS group and −8.04 mg C kg−1 soil d−1 in the high PFOS group. In contrast, in the F-53B-exposed groups, the RPE was positive, with values of 8.26 mg C kg−1 soil d−1 in the low F-53B group and 12.18 mg C kg−1 soil d−1 in the high F-53B group. Exposure of reeds to PFOS/F-53B stress resulted in differential effects on extracellular enzyme activities. The observed positive and negative RPE phenomena could be attributed to variations in extracellular enzyme activities. In conclusion, RPE responded differently under PFOS/F-53B exposure. [Display omitted] • Similar PFOS/F-53B exposure levels affected plant growth and root respiration alike. • Under PFOS/F-53B exposure reeds showed opposite effects on BG and AG activity. • RPE was positive under F-53B exposure and negative under PFOS exposure. • Enzyme activity variation under PFOS/F-53B stress may explains RPE differences. • Study offers insights into soil carbon dynamics under PFOS/F-53B exposure. [ABSTRACT FROM AUTHOR]

To ensure the sustainable use of phosphorus (P) fertilizers it is necessary to develop P management strategies that maximize crop yield while minimizing P leaching. Current P management practices, based on single agronomic soil P tests such as Olsen P (P OLSEN), do not consider the P sorption capacity allowing one to predict soil P dynamics in response to long-term P inputs and related impacts on crop yield, P uptake and P loss. The oxalate extraction method, measuring contents of P, aluminium (Al) and iron (Fe), has been identified as a high-potential agri-environmental P test as it measures the reversibly sorbed P pool. This test gives insights in the plant-available P pool, the P sorption capacity and the degree of P Saturation (PSD). In this study, we evaluated the performance of P OLSEN and PSD in explaining crop yield and P leaching risks, using long-term field experiments from China (n = 1) and Europe (n = 11), and we applied these insights to an inventory dataset (grid-sampling based) of Qiyang county in China. The variations in crop yield and P leaching risk were better explained by PSD (R2=0.5–0.95 for crop yield and 0.84–0.95 for P leaching risk) than by P OLSEN (R2=0.68–0.93 for crop yield and < 0.73 for P leaching risk). The PSD target level to achieve 90 % of the potential yield was higher than the critical level to avoid enhanced P leaching for the Chinese but not for the European experiments. When applied on regional scale, we showed that the use of P OLSEN might underestimate P demand for crop production and overestimate the potential leaching risk. Considering the theoretical advantages of PSD as a combined agri-environmental soil P test, we discussed the implications of its use for regional P management and showed that the α value, which is used to estimate PSD from oxalate extractable Al and Fe, needs to be adjusted for regional pedogenic and related climate factors. [Display omitted] • Compared with P OLSEN , PSD can better explain variations in crop yield and leaching risk at the farm level • Compared with PSD, P OLSEN might underestimate P demand and overestimate leaching risk • PSD can be a combined agri-environmental soil P test for guiding regional P fertilization • Adjusting α is necessary for developing fertilization strategies at the regional level [ABSTRACT FROM AUTHOR]

• Cropland to grassland conversion alters C-N-P stoichiometry in soil, microbes, and enzymes. • Conversion increases soil and microbial C:P and N:P ratios, suggesting reduced P availability. • Enzyme C:P ratio decreases, indicating microbial adaptation to changing nutrient status. • Environmental factors (clay, precipitation, pH) influence stoichiometric changes during conversion. • Longer conversion duration associated with more significant changes in C-N-P stoichiometry. In response to escalating land degradation, the conversion of cropland to grassland has emerged as a crucial mitigation strategy. This conversion has a significant influence on the stoichiometry of soil, microorganisms, and enzymes, specifically in relation to carbon (C), nitrogen (N), and phosphorus (P). A meta -analysis was conducted with 371 observations from 122 articles investigating the impacts of cropland to grassland conversion on the C-N-P stoichiometric dynamics of soils, microorganisms, and enzymes across China. The findings revealed that conversion significantly increased soil C:P (9.0%), soil N:P (5.6%), microbial C:N (15.5%), and notably, microbial C:P by 57.9%. This substantial increase in microbial C:P indicates that microbial communities are highly responsive to land use conversion. Contrastingly, the enzyme C:P ratio decreased by 19.8%, suggesting microbial adaptation to changing nutrient availability. The duration of conversion was positively correlated with soil C:P and N:P ratios, implying that relative P availability may decrease as conversion progresses. However, duration was negatively correlated with microbial C:P. Environmental factors such as clay content, mean annual temperature, and mean annual precipitation were positively correlated with microbial C:N and negatively correlated with microbial N:P, while soil pH was inversely correlated with microbial C:N. These results suggest the substantial influence of cropland to grassland conversion on soil, microbial, and enzyme stoichiometry, with particularly pronounced effects on microbial communities. The observed shifts in stoichiometric ratios suggest changes in nutrient cycling and availability following conversion. While these changes are primarily attributed to the land use conversion, we acknowledge that alterations in management practices, such as reduced fertilization, likely contribute to the observed stoichiometric shifts. Our findings emphasize the importance of considering both environmental factors and management practices when implementing grassland conversion initiatives. [ABSTRACT FROM AUTHOR]

• Soil water balance differed between monoculture and mixed plantations. • Soil water storage higher in monoculture compared with mixed plantations. • Ks and soil porosity had significant effects on soil water storage. The implementation of the "Grain-for-Green" program in China led to the extensive introduction of artificial vegetation, thereby intensifying evapotranspiration and the overuse of water resources. Thus, selecting suitable ecological vegetation and planting patterns to save water is a major challenge in the region. Three typical plants were selected in the Loess Plateau of China. The plants had been growing for 13 years. The soil water dynamics were studied based on measurements and Hydrus-1D modeling simulations under different precipitation scenarios (wet, normal, and dry years) and planting patterns (Stipa monoculture (S), a mixture of Stipa and Medicago (SM), and a mixture of Stipa , Medicago , and Caragana (SMC)). The results indicated that the soil water contents with S and SM were 25 % and 8 % higher than the stable field water capacity (SFC), respectively, whereas the SMC was 33 % lower than the SFC in the 0–100 cm depth in relatively normal precipitation years. The evapotranspiration was lowest under S (296–524 mm), followed by SM (351–628 mm) and SMC (368–669 mm). The soil water storage were 19–91 % and 12–58 % higher under S and SM than SMC. The soil desiccation intensity was more severe under SMC (0.3–0.5) than SM (0.5–1.1) and S (0.6–1.4). The soil water storage increased significantly with the annual precipitation (P <0.05), and increased by 54–85 % in relatively abundant water scenarios compared with scarce water scenarios according to Hydrus-1D model simulations. Partial least squares path modeling demonstrated that the soil saturated hydraulic conductivity (path coefficient = 0.478) and soil porosity (–0.703) had significant effects on soil water storage (P <0.01). The results further suggested that using shallow-rooted grass as the dominant plant would reduce water usage in areas with water scarcity, and mixed-species plantations (i.e., a mixture of shallow-rooted and deep-rooted grass) could reduce the loss of sediment in regions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Developed a comprehensive total nitrogen budget for an 8231 km2 catchment area. • The catchment was a total N sink, with a total 35 ktonnes N/yr, or 42.5 kg N/ha/yr. • 69% of the catchment acts as a net nitrogen sink, while 31% contributes as a nitrogen source. • Used the total N budget to test for nitrogen accumulation in the subsoils. • Analysis revealed N accumulation in grassland subsoils rather than arable land. Accurately quantifying the location and extent of nitrogen accumulation is crucial for mitigating its severe impacts on climate and the environment. Here we estimated a spatial total N budget and its input/output fluxes from different land uses on a 1 km2 grid scale across the whole of a large, mixed land use catchment (Trent, UK). With a long history of water quality monitoring, the Trent catchment provides a unique and ideal test bed for developing a detailed nitrogen budget and determining where N accumulation occurs. In 2015, a significant 35 (±5) ktonnes N accumulation was found, with 31 % of the area acting as a net source and 69 % as a net sink. The spatial budget ranged from −16 (±5) to 45 (±7) tonnes N/km2/year. Using this budget, we identified N accumulation and loss areas under diverse land uses and conducted strategic soil sampling and C/N analysis. Notably, grassland subsoil exhibited nitrogen buildup compared to arable land, spotlighting intricate land use, nitrogen, and soil dynamics. The study emphasizes the need for targeted nutrient management to prevent potential environmental repercussions linked to subsoil nitrogen accumulation, especially in grassland contexts. [ABSTRACT FROM AUTHOR]

• Microtopography could weaken the influence of soil-terrain factors on soil water. • Microtopography mainly affects deep layer soil water content. • Terraced microtopography improved soil water storage and temporal stability. • The most stable points of soil water usually correspond to a relatively flat middle slope area. Terraces have consistently been regarded as crucial measures for water conservation and vegetation restoration, particularly in mountainous environments. However, the hydrological effects of terraces in artificial forests have been rarely studied. In this study, detailed topography, soil properties and high-resolution (30 sites) soil water data (0–70 cm) observed from March 2015 to March 2016 were collected at hillslope scale (0.2 ha). The effects of static (soil properties and topography) and dynamic factors (precipitation) on the dynamics and variability of soil water content (SWC) were studied based on statistical methods, temporal stability and variance decomposition methods. The results showed that slope, topographic wetness index (TWI) and microtopography were the main control factors of different soil layers (shallow, middle and deep layer), which explained 37.2 %, 48.6 % and 47.3 % of the total variance of corresponding soil layers, respectively. Microtopography primarily affects deep layer soil water (40–70 cm). Level terraces show significantly higher soil water content (SWC) (30.89 ± 5.28 %) compared to gentle slopes (25.40 ± 5.33 %), steep slopes (27.05 ± 5.74 %), and scarps (19.71 ± 4.43 %) (P<0.05). Temporal stability of soil water varied across different depths, with shallow layer soil water exhibiting significantly weaker stability compared to other depths, the most representative point of different soil layers was located on relatively flat terraces. Decomposition of spatial variance revealed that the time-invariant component was the primary contributor to the total spatial variance, with a mean value over 70 %. These results highlight that microtopography could weaken the influence of soil-terrain factors on soil water, and the implementation of level terraces can enhance hillslope hydrological conditions in the Rocky Mountain area. [ABSTRACT FROM AUTHOR]

• Grassland hydrodynamics are responding in unexpected ways to concurrent climate change and woody encroachment. • Discharge has declined in recent decades despite > 100 years of climate wetting, suggesting a shift in hydrological connectivity. • Isotope trends indicate that changes in woody cover and climate led to increased contribution of winter precipitation to recharge. In grasslands around the world, climate change is occurring in tandem with woody encroachment (the spread of woody vegetation in grass-dominated ecosystems). State transitions from grassland to shrub/woodland have been identified aboveground via changes in species cover and composition, but the hydrological impact of these transitions is not well understood. Shifts from grass- to woody-dominance have the potential to impact evapotranspiration, soil moisture dynamics, and groundwater recharge. Therefore, it is possible that the consequences of aboveground vegetation change may be observable in the hydrological system. We leveraged long-term hydrological records from a tallgrass prairie site in northeastern Kansas, USA, to examine how concurrent changes in climate and land-cover have altered hydrological dynamics over the last century. Stream discharge has declined in recent decades despite > 100 years of climate wetting. The relationship between incoming precipitation and streamflow has weakened over the last 40 years, suggesting that shifts in the physical landscape are altering patterns of hydrological connectivity. Long-term isotope records show a divergence in the isotopic composition of precipitation (no change in δ18O) and stream/groundwater (decreasing δ18O) over the last decade. These results suggest that woody encroachment is accelerating the hydrological cycle, potentially by decreasing groundwater recharge (via increased evapotranspiration) and/or increasing infiltration rates (via creation of macropores). Holistically, these changes illustrate the interdependence of above- and below-ground processes in the local hydrological cycle, and the cascading long-term consequences (decades to centuries) for critical zone function once woody encroachment has occurred. [ABSTRACT FROM AUTHOR]

• Study uses CAE and models to analyze soil plasticity in tunneling. • Earth pressure is linked to soil plasticity to predict tunnel stability. • Confirmed CAE models soil plasticity for urban tunnel projects. • Managing soil plasticity with bentonite increases tunnel safety and efficiency. • Advocates MPS-CAE for real-time soil control in tunneling. This research delves into managing the plasticity of muddy soil in earth pressure balance (EPB) shield tunneling, crucial for ensuring tunnel stability and efficient sediment management in urban construction. The study utilizes a combination of a small-scale model experiment and a computer-aided engineering (CAE) analysis through the moving particle simulation (MPS) method to investigate how the plasticity of muddy soil, adjusted by mixing excavated soil with a bentonite solution, impacts the earth pressure within a tunneling chamber. The experimental setup meticulously simulates the tunneling process, measuring the variations in earth pressure that occur in response to the different states of plasticity induced by the agitation of the muddy soil. The findings reveal that earth pressure is a reliable indicator of the soil's plasticity, significantly correlating with the slump value and vane shear strength, thus affecting tunnel stability and the operation of machinery. The CAE analysis, underpinned by MPS, accurately mirrors the experimental outcomes, endorsing its use for assessing and visualizing the plasticity and fluidity of muddy soil in tunneling scenarios. The results of this study demonstrate that MPS-CAE analysis is an effective tool for improving sediment management strategies and optimizing EPB shield tunneling operations, highlighting the critical role of soil plasticity in ensuring tunnel face stability and project success. This research reveals that earth pressure measured by the agitation blade can serve as a reliable indicator of the plasticity of muddy soil in the chamber. This enables real-time and on-site evaluation of soil conditions during EPB shield tunneling. [ABSTRACT FROM AUTHOR]

• Continuous cropping of lisianthus led to soil salinity and soil function loss. • Fungal community experienced significantly decline in biomass and diversity. • No apparent accumulation of pathogens with continuous cropping. • Loss of prebiotics and accumulation of autotoxicants with continuous cropping. • Soil metabolites alteration is the main driver in the development of soil sickness. Continuous cropping obstacle (CCO) is becoming a serious threat to the quality production of lisianthus (Eustoma grandiflorum). However, investigations of the causal mechanism of CCO in lisianthus are still lacking. To this end, soil biotic dynamics and metabolites alterations were illuminated using metagenomic sequencing and metabolomic profiling along a chronosequence that has cultivated lisianthus from 2 weeks to 6 years. Soil EC and nutrient contents increased significantly as the cultivation duration prolonged. Fungal community has undergone significant decline in their diversity and biomass. Nevertheless, no apparent accumulation of pathogenicity-related microbes was observed along the investigated chronosequence. The alterations of soil metabolites along the chronosequence reflect the decline of microbial activity, the accumulation of phytotoxic compounds and the loss of metabolite involved in beneficial plant-microbe interactions. As a result, lisianthus plants in the longer continuous cropping soil experienced stressful condition as evidenced by the increasing trend of stress responsive metabolites and the overall soil function deterioration as indicated by soil enzymes. Hierarchical partitioning analysis showed that the investigated factors can explain a total of 92.25 % of the variations in the soil function degradation. Of which, soil metabolite alteration was the most important factor in explaining the CCO development, covering 24.55 % of the explainable variations. Spearman's correlation results further implied that soil metabolite alteration is the main driver in the development of CCO in lisianthus, especially by mediating the plant-microbes interactions. Our findings revealed a general pattern of soil biotic and abiotic response to the continuous monocropping of lisianthus and suggest that the overcome of the CCO in lisianthus requires further studies focusing on the crucial metabolites and their interactions with microbes. [ABSTRACT FROM AUTHOR]

Internal solitary waves (ISWs) are a frequently observed phenomenon in the ocean and significantly affect sediment soil dynamics and transportation. This study entailed the use of the poroelastic theory to investigate ISW-induced soil responses. To validate this theory, the solution for pore pressure was compared with a set of laboratory measurements. The theoretical results agree well with the experimental data, indicating that the poroelastic solution can be used to study ISW-induced soil dynamics. The Dubriel–Jacotin–Long (DJL) model was used to examine the flows and pressure induced by a large ISW observed in the northern South China Sea, and the wave–driven pressure at the water–seabed interface was obtained. The validated analytical solution was then used to analyze the ISW-induced soil dynamics for sandy silt and clayey silt. The results indicate that the effective stresses are relatively small under the observed ISW, and the stress angle inside the clayey silt is larger than that inside the sandy silt owing to the smaller penetrated depth. According to the Mohr-Coulomb criterion, shear failure is difficult to happen under the observed ISW conditions and seabed properties. Moreover, the effects of the water density profile and shear modulus on the shear failure potential of the soil were analyzed. The results show that the ISW-induced soil dynamics are sensitive to the shear modulus of soil and the density profile of water. In the event of substantial density variations in the pycnocline, shear failure may occur within the seabed in regions with a large shear modulus. • Soil dynamics significantly affected by internal solitary waves. • Shear failure can be caused by internal solitary waves within the seabed. • Shear failure happens before the occurrence of liquefaction. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) in agricultural plastic film mulching system changes microbial functions and nutrient dynamics in soils. However, how biodegradable MPs impact the soil gross nitrogen (N) transformations and crop N uptake remain significantly unknown. In this study, we conducted a paired labeling 15N tracer experiment and microbial N-cycling gene analysis to investigate the dynamics and mechanisms of soil gross N transformation processes in soils amended with conventional (polyethylene, PE) and biodegradable (polybutylene adipate co-terephthalate, PBAT) MPs at concentrations of 0 %, 0.5 %, and 2 % (w/w). The biodegradable MPs-amended soils showed higher gross N mineralization rates (0.5–16 times) and plant N uptake rates (16–32 %) than soils without MPs (CK) and with conventional MPs. The MPs (both PE and PBAT) with high concentration (2 %) increased gross N mineralization rates compared to low concentration (0.5 %). Compare to CK, MPs decreased the soil gross nitrification rates, except for PBAT with 2 % concentration; while PE with 0.5 % concentration and PBAT with 2 % concentration increased but PBAT with 0.5 % concentration decreased the gross N immobilization rates significantly. The results indicated that there were both a concentration effect and a material effect of MPs on soil gross N transformations. Biodegradable MPs increased N-cycling gene abundance by 60–103 %; while there was no difference in the abundance of total N-cycling genes between soils without MPs and with conventional MPs. In summary, biodegradable MPs increased N cycling gene abundance by providing enriched nutrient substrates and enhancing microbial biomass, thereby promoting gross N transformation processes and maize N uptake in short-term. These findings provide insights into the potential consequences associated with the exposure of biodegradable MPs, particularly their impact on soil N cycling processes. [Display omitted] • We quantify the soil gross N transformation rates in response to different MPs. • Biodegradable MPs increase N-cycling genes attributed higher nutrient substrates. • Biodegradable MPs stimulate soil N transformations by affecting N-cycling genes. • Biodegradable MPs increase maize N uptake rates and biomass. • There are both concentration and material effect of MPs on gross N transformations. [ABSTRACT FROM AUTHOR]

[Display omitted] • Soil base cation fluxes and shallow subsurface flow exhibit high, but predictable spatial variation. • Soil saturation frequency at 20 cm is the best predictor of base cation fluxes. • Catchment structure spatially organizes soil saturation frequency. • Base cation fluxes are greatest in soils that were most weathered. Hydrologic behavior and soil properties across forested landscapes with complex topography exhibit high variability. The interaction of groundwater with spatially distinct soils produces and transports solutes across catchments, however, the spatiotemporal relationships between groundwater dynamics and soil solute fluxes are difficult to directly evaluate. While whole-catchment export of solutes by shallow subsurface flow represents an integration of soil environments and conditions but many studies compartmentalize soil solute fluxes as hillslope vs. riparian, deep vs. shallow, or as individual soil horizon contributions. This potentially obscures and underestimates the hillslope variation and magnitude of solute fluxes and soil development across the landscape. This study determined the spatial variation and of shallow soil base cation fluxes associated with weathering reactions (Ca, Mg, and Na), soil elemental depletion, and soil saturation dynamics in upland soils within a small, forested watershed at the Hubbard Brook Experimental Forest, NH. Base cation fluxes were calculated using a combination of ion-exchange resins placed in shallow groundwater wells (0.3 – 1 m depth) located across hillslope transects (ridges to lower backslopes) and measurements of groundwater levels. Groundwater levels were also used to create metrics of annual soil saturation. Base cation fluxes were positively correlated with soil saturation frequency and were greatest in soil profiles where primary minerals were most depleted of base cations (i.e., highly weathered). Spatial differences in soil saturation across the catchment were strongly related to topographic properties of the upslope drainage area and are interpreted to result from spatial variations in transient groundwater dynamics. Results from this work suggest that the structure of a catchment defines the spatial architecture of base cation fluxes, likely reflecting the mediation of subsurface stormflow dynamics on soil development. Furthermore, this work highlights the importance of further compartmentalizing solute fluxes along hillslopes, where certain areas may disproportionately contribute solutes to the whole catchment. Refining catchment controls on base cation generation and transport could be an important tool for opening the black box of catchment elemental cycling. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mixed stands presented greater SOC storage and stability than pure stands. • Microbial CUE, diversity and network complexity were enhanced after mixing. • Biotic factors affected SOC storage and stability more than abiotic factors did. • Role of microbial communities in SOC dynamics relied on soil multifunctionality. Forest conversion can impact soil organic carbon (SOC) fixation and ecosystem functions. The newly proposed "evenness of SOC chemical components" index can indicate the permanence of stored SOC during environmental disturbances. However, how the mixing of tree species impacts SOC accumulation and persistence and changes in soil microbial communities and multifunctionality remain unknown. Thus, we conducted a field experiment (11 years) of monospecific Eucalyptus urophylla × E. grandis plantation for evaluating the influences of the mixed planting of a non-nitrogen (N)-fixing tree, Castanopsis hystrix , and an N-fixing tree, Dalbergia odorifera , on SOC accumulation and chemical stability. Compared with pure plantations, mixed Eucalyptus plantations (particularly those mixed with D. odorifera) exhibited significantly increased SOC concentrations by 28.60–33.71 % and increased SOC chemical component evenness by 3.96–4.67 % (P < 0.05). We also found that the concentrations and chemical component evenness of SOC were strongly linked with litter quality, soil N, phosphorus and their availability, multifunctionality, microbial activity, carbon use efficiency (CUE), biomass, diversity, and network complexity. Furthermore, tree species mixing increased litter quality, soil nutrient availability, microbial biomass, activity, diversity, CUE, and network complexity. Soil microbial anabolism, community characteristics and multifunctionality influenced the SOC concentrations and SOC chemical components evenness. Specifically, microbial diversity enhanced the concentrations and chemical component evenness of SOC by increasing network complexity and soil multifunctionality. These findings revealed differential responses and mechanistic controls of SOC accumulation and chemical stability in different Eucalyptus planting patterns. Overall, mixed plantations, particularly those in which N-fixing species were introduced, effectively improved SOC accumulation and stabilization by positively altering soil quality and microbial properties, potentially representing a sustainable forestry management strategy to improve soil C benefits and multifunctionality in forest ecosystems. [ABSTRACT FROM AUTHOR]

[Display omitted] • Soil organic composition is induced by climate and soil cover. • Soil organic matter accumulation is different between and within horizons. • Pedogenic development positively influenced C storage. • Greater stability of organic matter in soil subsurface. • Planosols are important in the C stock, mainly in depth. Planosols have sandy-textured surface horizons that abruptly cover a dense subsoil with high clay content, which usually limits drainage and influences soil moisture. Here, we investigated changes in C storage through the pedogenic horizons of soil profile, including detailed sampling of A and B horizons along a transect to cover rainfall variation (584–1130 mm year−1) and soil cover of Planosols, including dry land areas in Northeast Brazil. The soil profile located under highest precipitation and with the greatest pedogenic development (150 cm) showed the largest C stock (101.91 Mg/ha), surpassing estimates of other soil classes. In addition, our results suggest that soil cover and pedogenesis impact C storage in Planosols. An average of 64 % of C is stored in subsurface horizons that present abundant clay fraction; thus, the dynamics of subsurface soil organic carbon (SOC) appear to be more controlled by soil features than by climate. Values of δ13C indicated the predominance of C3 plant, except in area with sugarcane cultivation (C4 plant). Changes in C distribution within the horizon suggest changes in degree of decomposability of soil organic matter (SOM), mainly in A1 and B1 layers, with A horizon richer in labile compounds. δ15N values indicated that N dynamics differ in the gradient. The thermal analyses showed that around 70 % or more of humin fraction is composed of structures more resistant to degradation, suggesting that C stock in Planosols has relative stability. However, in driest part of the climate transect, SOM may be more vulnerable to losses due to the large relative quantity of aliphatic groups in soil surface and subsurface. This work provides insights into the mechanisms the determine C storage distribution in tropical Planosols and contributes to appropriate use and management of these soils to ensure the valuable ecosystem service of C storage. [ABSTRACT FROM AUTHOR]

[Display omitted] • A modified sequential extraction method of SPFs was applied in this study. • Northeastern regions and areas along the Yangtze River were more susceptible to phosphorus leaching. • Temperature showed a positive effect on labile and medium-stable P. • Elevation was the predominant environmental factor for SPFs in TGRA. The spatial distribution of soil phosphorus fractions (SPFs) in the Three Gorges Reservoir area (TGRA) is crucial for evaluating water quality and lake eutrophication in the lower reaches of the Yangtze River. Besides, it is also unclear whether climate change and rising elevation will alter the risk of phosphorus loss in this region. To address this knowledge gap, soil samples were extensively collected in Chongqing section of the TGRA and extracted SPFs using a rapid sequential extraction method. Results indicated that Ustifluvents, Haplustepts, and Kanhaplustults are suitable for cultivation but also prone to the risk of phosphorus leaching due to high labile phosphorus concentration. Increased temperature positively affected labile and medium-stable phosphorus, while increased precipitation accelerated phosphorus leaching. Solar radiation has significant effects on medium-stable and stable phosphorus. Additionally, multivariate and redundancy analysis showed that different SPFs were influenced by various environmental factors, but elevation is the predominant factor affecting most SPFs in the TGRA. Northeastern TGRA and areas with lower elevations on both sides of the Yangtze River were more susceptible to phosphorus leaching. This study is expected to provide decision-makers with references and help manage the regional environment in the context of climate change. [ABSTRACT FROM AUTHOR]

• Use of SoLIM-generated soil data in the SWAT model produces reliable results. • Forested areas resulted in higher output uncertainty compared to grasslands and paddy fields. • Higher slope introduces increased uncertainty in the hydrological processes. • Uncertainty patterns differ during flood and non-flood seasons simulated with SWAT. • Evaporation, Φ d , and K sat are key contributors to uncertainty in the SWAT simulation. Hydrological models are essential tools for understanding natural processes, yet they often encounter with uncertainties due to limited input data and simplified assumptions. Soil data is a crucial input parameter for hydrological models, but it faces cartographic challenges due to lack of standardized soil mapping methods. To explore the applicability of soil datasets derived from the Third Law of Geography in hydrological models, the Soil Landscape Inference Model (SoLIM) based on this principle is used to generate a soil dataset. This dataset is then utilized as input data for a semi-distributed hydrological model (Soil and Water Assessment Tool, SWAT) to assess the impact of soil dataset uncertainty on performance of the hydrological model. This study, utilized the Fengyu River Watershed in Yunnan Province, China as an example, showed that: 1) Although the integration of SoLIM-generated soil data into the SWAT model introduces sensitivity in sediment yield, the overall results remain reliable. This suggests that soil datasets based on the Third Law of Geography can serve as input for semi-distributed hydrological models. 2) Uncertainty introduced by SoLIM-generated soil data affects parameters such as evaporation, total porosity of the soil layer (Φ d), and groundwater infiltration coefficient (K sat). These variations influence the sensitivity of SWAT's predictions regarding streamflow and water quality. 3) Factors influencing model outcomes include steeper slopes in certain areas, which enhance streamflow velocity and flow rates, resulting in more dynamic and non-linear responses. Additionally, soil water dynamics exhibit higher temporal and spatial variability in forests compared to pasture and rice paddy fields, where vegetation tends to be more uniform, maintaining stable soil water loss pathways and reducing uncertainty in streamflow predictions. The study provides a foundation for studies addressing the difficulties in acquiring high-precision soil datasets for such models. [ABSTRACT FROM AUTHOR]

Fire has important effects on soil properties and functioning in terrestrial ecosystems that have been explored by many studies. Limited information exists on the alterations in soil parameters over time caused by fire disturbance in semi-arid climates. This study is designed to examine the influence of fire disturbance on the change of soil physical, chemical, and biological properties over time in a semi-arid region. In the summer of 2007, a severe natural fire occurred in the Pideh region of northern Iran, dominated by hawthorn (Crataegus melanocarpa M.B.) and berberis (Berberis integerrima Bunge), which destroyed almost 80 % of the shrubs and the majority of the co-dominant plants over a vast area. For this research, 12 soil samples (0–10 cm depth) were taken in summer (August) in different years (i.e., 2010, 2013, 2016, 2019, and 2022) from the burnt area. Furthermore, a total of 12 soil samples were collected during the summer (August) of 2022 from unburned regions to serve as a control. Soil biological parameters were studied by conducting soil samplings in the summer (August) and autumn (November) of every year. To evaluate soil N mineralization, soil samplings were done in summer (August and September) and autumn (November and December). Our results indicated that the occurrence of fire increased soil bulk density, with a concomitant decline in soil organic matter (SOM), porosity, aggregate stability, particulate organic carbon and nitrogen (POC and PON), as well as available nutrients such as ammonium (NH 4 +) and nitrate (NO 3 −) levels. Additionally, microbial parameters (respiration and biomass) and enzymes (urease, acid phosphatase, arylsulfatase and invertase), experienced a decrease in areas affected by the fire over time of 2010 to 2022. Unburnt (2022) and burnt (2022) sites had higher density and biomass of the three earthworm groups. Acari, Collembola, nematodes, protozoans, fungi and bacteria were significantly affected by fire disturbance in the different seasons, and years, and declined in the order unburnt sites > burnt sites 2022 > burnt sites 2019 > burnt sites 2016 > burnt sites 2013 > burnt sites 2010, respectively. Fire has complex effects on soil, involving interactions among physical, chemical, and biological properties that may persist for a prolonged period. After fifteen years of fire disturbance, soil characteristics were different in the burned (2022) and unburned areas. This research offers valuable insights into the impact of fire on soil characteristics over time, as well as a comparison with an unburned area. Therefore, it is essential to adopt soil management practices to minimize soil disruption in burned areas and facilitate the full recovery of soil ecosystems after fire damage. [Display omitted] • The response of soil physical and chemical properties to fire is variable and very complex • Fire disturbance reduced soil nutrients and N mineralization in a semi-arid climate • Soil fauna and microflora population decreased following fire event • Soil microbial and stoichiometry of enzyme properties were negatively affected by fire • Soil properties not fully recovered even fifteen years after the fire disturbance. [ABSTRACT FROM AUTHOR]

The utilization of integrated systems in livestock production has been implemented as a practice aimed at intensifying pasture area utilization while maintaining sustainable soil management to enhance total organic carbon (TOC) storage. However, the dynamics of organic carbon in the soil of integrated systems, involving the inclusion of legumes or tree components in pastures, are not fully understood. Our research assessed soils from pastures composed of grass-legume consortia (GLS), silvopastoral systems (SPS), and monoculture grass pastures (MP), comparing them to native forest soil (NF) in the Cerrado biome, at different evaluation depths: 0–5 cm, 5–10 cm, 10–20 cm, and 20–30 cm. The objective was to evaluate the potential of each system to store carbon in the soil in contrast to native forest soil by determining the labile carbon, water-soluble organic carbon, microbial biomass carbon, total carbon, total nitrogen, carbon management index, and soil carbon stock. No differences were observed for TOC and soil carbon stock between GLS and SPS, but both were demonstrated to be lesser than in the NF soil (p < 0.05). SPS, MP, and NF did not differ in terms of labile carbon, water-soluble carbon, and microbial biomass carbon content (p > 0.05), while GLS did not show similarity to NF in any of the analyzed variables (p < 0.05). Only the SPS achieved a CMI >100 in all soil depth ranges evaluated. Our study demonstrated that the association among labile carbon fractions dynamics and the relationship between CMI and soil biological attributes can be used as a proxy for TOC dynamics and indicators of a production system's potential to sequester carbon in the soil. Collectively, the studied variables indicate that the silvopastoral system exhibited greater potential for carbon recovery compared to the grass-legume integration system or monoculture grass pasture. • We assessed the effect of legumes or silvopastoral system on soil C. • The inclusion of trees into grasslands increases labile organic soil C. • Soil C stocks were least in integrated system compared to native vegetation and pasture monoculture. • The least soil C stocks and C fractions were observed in the grass-legume system. • The dynamics of labile C fractions can be used as a proxy of TOC dynamics in soil. [ABSTRACT FROM AUTHOR]

• Legume-based intercropping systems in pear orchard improved overall soil health. • The introduction of legumes in pear orchard as intercrops improves the pear fruit yield. • Early-season sowing of intercrops fetch more net returns due to increased market prices. • The Pear-based agroecosystem has the potential to increase system productivity and profitability in a sustainable manner. North-western Indian farmers are increasingly showing interest in adopting horticulture-based systems to enhance their farm productivity with anticipated profits. So, there is a need for systematic evaluation of different pear-based agroecosystems with respect to its productivity, profitability, soil health, and biodiversity to tackle the problems of modern agriculture (food security, declining soil health, and sustainability). Therefore, an intercropping experiment comprising 11 treatments viz. [T 1 : Pear (Pyrus communis) + Pea (Pisum sativum), T 2 : Pear + Radish (Raphanus sativa), T 3 : Pear + Coriander (Coriandrum sativum), T 4 : Pear + Kasuri fenugreek (Trigonella corniculata), T 5 : Pear + fenugreek (Trigonella foenum-graecum), T 6 : Pear + Spinach (Spinacia oleracea), T 7 : Pear + Green onion (Allium fistolosum), T 8 : Pear + Cauliflower (Brassica oleraceae var. botrytis), T 9 : Pear + Toria (Brassica rapa), T 10 : Pear + Knol khol (Brassica oleraceae var. gongylodes) and T 11 : Pear monoculture] were laid out in randomized block design with three replications at farmer's field, Tarn Taran district, Punjab, India during 2021–22 and 2022–23. The results showed that the lesser values of bulk density (1.30 g/cm3) and higher water holding capacity (42.52%) were observed in the Pear + kasuri fenugreek intercropping system. All the legumes-based intercropping systems viz. Pear + kasuri fenugreek, Pear + fenugreek, and Pear + pea were significantly efficient in bringing enhancements to the chemical properties of the orchard's soil. Under various pear-based intercropping systems, different microbial populations (bacteria, fungi, actinomycetes, and diazotrophs) were significantly higher in legume-based intercropping systems of Pear + kasuri fenugreek, Pear + fenugreek, and Pear + pea and resulting in more enzymatic activity in the soil in terms of dehydrogenase (63.02, 61.88, and 60.48 µg TPF/g of soil/hour, respectively), alkaline phosphatase (10.05, 9.92, and 9.75 µg PNP/g of soil/hour, respectively) and urease (17.84, 17.18, 17.00 µg /g of soil/hour, respectively). The intercropping system of Pear + kasuri fenugreek significantly increased microbial biomass carbon (42.20%) and microbial biomass nitrogen (65.02%) over Pear monoculture. The correlation analysis of various soil's physiochemical and biological parameters indicated significant associations among themselves at p = 0.01, 0.05. The intercropping system of Pear + kasuri fenugreek also produced significantly higher system productivity in early (122.20 kg/ha/day in 2021–22 and 123.86 kg/ha/day in 2022–23) and main season (119.08 kg/ha/day in 2021–22 and 121.60 kg/ha/day in 2022–23) due to significantly higher pear yield (340.02 q/ha in 2021–22 and 341.89 q/ha in 2022–23) and higher pear equivalent yield (105.99 in early season, 94.64 q/ha in main season of 2021–22 & 110.20 in early season, 101.94 q/ha in main season of 2022–23) observed by kasuri fenugreek, resulting in higher net returns, BC ratio and economic efficiency in both seasons during both years over other intercropping systems. [ABSTRACT FROM AUTHOR]

In geotechnical earthquake engineering, the seismic displacement is regarded as a more balanced index to explain the co-seismic performance of soil slopes. The Newmark's sliding block theory is usually adopted to fast estimate the seismic slope displacement, and subject to different assumptions of the sliding soil mass, various improvements can be made onto the Newmark's sliding block models. In this paper, the Newmark's sliding block model is further modified to calculate the seismic displacement of shallow slopes composed of cohesive soils. The research significance is highlighted by several novel considerations: (1) the yield acceleration of translational sliding soil column derived from infinite slope model is modified to be displacement-dependent and is analytically expressed by simulating the seismic strain-softening effect of the undrained soil shear strength; (2) subjected to rotational sliding mode, the slope yield acceleration is further modified to reflect the change of slip surface geometries in the course of co-seismic downward slope movement; and (3) the seismic slope displacement model fully considers the flexibility of the soil mass by simulating the nonlinear dynamic vibration response of flexible soil columns, which is further coupled within the Newmark's sliding block model. Verifications of the proposed modelling procedure were made by seismic displacement analysis of several numerical examples against strong earthquake records provided by NGA-West2. The comparison results calculated from different models show that ignoring the dynamic characteristics of the slope yield acceleration will underestimate the seismic slope displacement to some extent, which is undesirable in geotechnical risk management. [ABSTRACT FROM AUTHOR]

Microbial processes mediating the cycling of carbon and nutrients in soils are complex and thus difficult to predict with mathematical models. Such complexity arises because biological and ecological dynamics interact with physical processes in the soil to shape patterns of resource acquisition and use, and ultimately of organic matter stabilization in soil. In the article collection "Advances in Modelling Soil Microbial Dynamics" (https://www.sciencedirect.com/special-issue/10DG8MTGCCF), novel mathematical approaches to tackle these complexities are presented. This perspective summarizes their findings by highlighting theoretical advances and outstanding challenges in modelling microbial processes and their physical constraints. • Soil microbial models are becoming more diverse and complex. • New models represent mechanisms of resource acquisition, use, and fate. • New models also explore physical and eco-evolutionary constraints. • Challenge 1: balance representation of physical and biological processes. • Challenge 2: balance process detail and associated uncertainties. [ABSTRACT FROM AUTHOR]

Biochar amendment is a promising strategy for mitigating antibiotic resistance genes (ARGs) in soil and plants, but its effects on ARGs at field scale are not fully understood. Here, field trials were executed utilizing two plant varieties, Brassica juncea and Lolium multiflorum , with four types of biochar to investigate changes in ARGs and microbiome in soil, rhizosphere, root endophytes, and leaf endophytes. Results showed that biochar altered ARG distribution in soil and plant, and restrained their transmission from soil and rhizosphere to endophytes. A reduction of 1.2–2.2 orders of magnitude in the quantity of ARGs was observed in root and leaf endophytes following biochar addition, while no significant changes were observed in soil and rhizosphere samples. Procrustes and network analyses revealed significant correlations between microbial communities and mobile genetic elements with ARGs (P < 0.05). Besides, redundancy and variation partitioning analysis indicated that bacterial communities may play a dominant role in shaping the ARGs profile, contributing to 43 % of the variation observed in ARGs. These field results suggest that biochar amendment alone may not fully alleviate ARGs in soil, but it has a significant beneficial impact on food safety and human health by effectively reducing ARGs in plant endophytes. [Display omitted] • Biochar restrained ARGs transmission from the soil and rhizosphere to endophytes. • Biochar amendments reduced 1.2-2.2 orders of magnitude in ARGs in endophytes. • Bacterial communities could play a dominant role in shaping the ARGs profile. [ABSTRACT FROM AUTHOR]

To optimally employ Natural Source Zone Depletion (NSZD) and Enhanced Source Zone Depletion (ESZD) at sites impacted by light non-aqueous phase liquids (LNAPL), monitoring strategies are required. Emerging use of subsurface oxidation-reduction potential (ORP) sensors shows promise for tracking redox evolution, which reflects ongoing biogeochemical processes. However, further understanding of how soil redox dynamics relate to subsurface microbial activity and LNAPL degradation pathways is needed. In this work, soil ORP sensors and DNA and RNA sequencing-based microbiome analysis were combined to elucidate NSZD and ESZD (biostimulation via periodic sulfate addition and biosparging) processes in columns containing LNAPL-impacted soils from a former petroleum refinery. Results show expected relationships between continuous soil redox and active microbial communities. Continuous data revealed spatial and temporal detail that informed interpretation of the hydrocarbon biodegradation data. Redox increases were transient for sulfate addition, and sequencing revealed how hydrocarbon concentration and composition impacted microbiome structure and naphthalene degradation. Periodic biosparging did not result in fully aerobic conditions suggesting observed biodegradation improvements could be explained by alternative anaerobic metabolisms (e.g., iron reduction due to air oxidizing reduced iron). Collectively, data suggest combining continuous redox sensing with microbiome analysis provides insights beyond those possible with either monitoring tool alone. [Display omitted] • Redox dynamics and active microbiomes investigated during natural source zone depletion (NSZD) and enhanced SZD. • Continuous ORP data resolves distinct spatial/temporal patterns impacting biodegradation performance. • ORP measurements consistent with active microbiome structure data. • Differences in LNAPL composition affect naphthalene degradation mechanism. • Active Smithella spp. prevalent in alkane rich environments. [ABSTRACT FROM AUTHOR]

• A single-point sensor cannot evaluate soil moisture in a heterogeneous environment. • TSA provides a better understanding of sensor network distribution. • The CRNP offers a reliable solution to capture SSM in challenging environments. • CRNP provides a reference for SM product evaluation in forested mountain terrain. Soil moisture is critical to the Earth's water cycle as it influences water exchange between the land, atmosphere, and oceans. This study assessed the potential of a cosmic-ray neutron probe (CRNP) to monitor soil moisture dynamics in a forested mountain region, which is critical for water resource management and ecosystem health. Accurate soil moisture monitoring is essential for effectively managing forested mountainous areas, but various limitations exist in such environments. To overcome the complexities of soil moisture monitoring, an observatory consisting of a CRNP, automatic weather sensors, and dataloggers was established. Fifteen capacitance sensor (CS) stations were placed strategically within the CRNP's footprint to ensure strict evaluation. Although each CS measurement revealed the heterogeneity of the experimental site, temporal stability analysis determined the representative soil moisture. The validation of the CRNP and the average results of the 15 surface CS sensors revealed that they were strongly correlated (R = 0.94). It means that the CRNP can describe the dynamics of soil moisture that fluctuate according to physical properties, underscoring its reliability in estimating intermediate scale soil moisture. This correlation remained robust despite differences in rainfall patterns over three years. These findings indicate that the CRNP may be a valuable tool for monitoring soil moisture in a challenging environment. Additionally, the evaluation of the Advanced Microwave Scanning Radiometer-2 (AMSR2), Advanced Scatterometer (ASCAT), and Global Land Data Assimilation System (GLDAS) demonstrated the usefulness of CRNP in supplying reference data. The AMSR2 showed an inadequate temporal pattern (R = 0.35), and the ASCAT achieved the highest correlation agreement (R = 0.67) with the CRNP. The GLDAS also showed close agreement, although with some discrepancies (R = 0.52). The results of this study support the utilization of CRNP and provide insight into establishing and expanding a soil moisture network. [ABSTRACT FROM AUTHOR]

The dynamics of soil organic carbon stocks (SOCS) in croplands are highly sensitive to agricultural management practices, representing a crucial component of soil fertility and playing a pivotal role in regulating the global carbon cycle. However, the historical trajectory of SOCS in croplands and its future developments in response to agricultural management practices such as carbon inputs coupled with the impact of climate change, remain unclear, especially for the areas with intensive human activities. Here we collected a total of 1219 cropland SOCS data (0–20 cm) from the southern Jiangsu Province of China in 1980, 2000, and 2015, and the RothC-RFst model developed by integrating the RothC-predicted SOCS into the space-for-time random forest (RFst) was used to model spatiotemporal dynamic of cropland SOCS over the period of 1980–2015 and its future trend under three carbon input scenarios (CI+1, CI+0.6, and CI+0). Results showed that the historical change in SOCS from 1980 to 2015 was characterized as a significant increase of SOCS (+6.02 t C ha-1) before 2000 and SOCS decline (-5.05 t C ha-1) over the period of 2000–2015. The future trend of cropland SOCS under different CI scenarios were similar during 2024–2100, with substantial SOCS increases of 6 % and 4 % under CI+1 and CI+0.6, and almost unchanged SOCS (<1 %) for the baseline scenario (CI+0). The projected dynamics of SOCS indicated a constrained response to future climate change (e.g., the CMIP6 SSP1–1.9 and SSP5–8.5) under the CI-based scenarios. These findings highlight the significant role of the CI levels in preserving and enhancing cropland soil carbon sequestration potential. We believe that outputs from this study provide valuable insights for the development of cropland management strategies through effective economic and policy incentives, especially in areas heavily impacted by human activities. • Cropland soils functioned as important C sinks in the past. • The elevated CI promotes SOCS, even in the face of extreme climate constraints. • The SOCS is projected to increase by 6 % with annual growth rate of 1 % in CI levels. • SOCS dynamic remains dynamic balance under current CI and SSP1–1.9/SSP5–8.5. [ABSTRACT FROM AUTHOR]

Mixed plantations have emerged as a promising approach to improve soil health and contribute to sustainable land management. Despite the numerous field experiments conducted so far, there is no clear consensus on the impacts of mixed plantations on soil physicochemical properties due to the wide range of findings. This meta-analysis synthesizes findings from 252 studies across China to provide a comprehensive evaluation of these effects within both monoculture and mixed plantation contexts. We quantified the effects of mixed versus monoculture plantations on key soil physicochemical properties, including soil moisture content, bulk density, pH, and nutrient indicators such as soil organic matter, total nitrogen, available nitrogen, total phosphorus, available phosphorus, total potassium, and available potassium. Additionally, we identified the primary drivers of these changes, focusing on factors such as initial soil pH, elevation, mixing proportion, and plantation age. Compared to monocultures, mixed plantations significantly enhanced key soil physicochemical properties, with available potassium, soil organic matter, and available phosphorus each increasing by 18 %. However, soil pH only increased by 1 %. The magnitude of the response varied significantly across different analytes, influenced by factors including initial soil pH, elevation, mixing proportion, and plantation age, underscoring the complex interactions that affect soil dynamics under different plantation management strategies. • Mixed plantations significantly reduce soil bulk density. • Mixed plantations increased soil organic matter (SOM) by 44.91 %. • Mixed plantations increased soil available potassium and phosphorus by 17.72 % and 17.64 %. • A positive correlation between SOM and soil moisture and total N has been identified. [ABSTRACT FROM AUTHOR]

• Snow coverage alteration has immediate and carry-over impacts on soil C pools. • Snow removal enhances DOC and TOC in spring. • Snow addition enhances soil respiration immediately and in the following summer. • The response of microbial biomass to snow addition was affected by ecosystem type. • Relative change in snow depth determines the extent of snow treatment impacts. Snow distribution has been altered over the past decades under global warming, with a significant reduction in duration and extent of snow cover and an increase in unprecedented snowstorms across large areas in cold regions. The altered snow conditions are likely to have immediate (in winter) and carry-over or legacy (which an extended effect might continue in the following spring, summer and autumn) impacts on soil processes and functioning, but a quantification of the legacy effect of snow coverage alternation is still lacking. Furthermore, studies investigating the effect of snow cover changes on soil respiration, soil carbon pools and microbial activity are increasing, but contrasting results of different studies makes it difficult to assess the overall effect of snow cover changes and the underlying mechanisms, thus a systematic and comprehensive meta -analysis is required. In this study, we synthesized the results from 60 papers based on field snow manipulation experiments and conducted a meta -analysis to evaluate immediate and prolonged effects on eight variables related to soil carbon dynamics and microbial activity to snow coverage alternation. Results showed that snow removal had no significant effect on soil respiration, but increased dissolved organic carbon (DOC) (11.5%) and fungal abundance (32.0%). By contrast, snow addition significantly increased soil respiration (16.3%) and microbial biomass carbon (MBC) (6.6%). Snow addition had immediate and prolonged impacts on soil carbon dynamics and microbial activity lasting from winter to the following autumn, whereas an effect of snow removal on total organic carbon (TOC) and DOC was detectable only in the following spring. Snow depth, ecosystem and soil types determined the extent of the impact of snow treatments on soil respiration, DOC, MBC and microbial biomass nitrogen (MBN). Our findings provide critical insights into understanding how changes in snow coverage affect soil respiration and microbial activity. We suggest future field-based experiments to enhance our understanding the effect of climate change on soil processes and functioning in the winter and the following seasons. [ABSTRACT FROM AUTHOR]

• DGT and KCl-extraction of soil mineral nitrogen were compared. • Both methods were equally predictive of plant relative yield and N uptake. • NH 4 measured by DGT or KCl was not correlated with plant N uptake. • KCl has an advantage over DGT due to its low cost and ease of application. Determining soil nitrogen (N) availability is essential in agriculture to minimise over-application, maximise growers' returns and reduce potential environmental consequences. The present study assesses soil mineral N (nitrate-N and ammonium-N) using the diffusive gradients in thin-films (DGT) technique against the conventional potassium chloride (KCl) extraction. The DGT technique has demonstrated reliable predictability for plant-available P, Cu and Zn. However, the use of DGT to quantify soil N bioavailability is underreported and N measurements made with DGT have not been compared to plant growth responses or N uptake. A pot trial using wheat was performed to determine the suitability of the DGT technique to predict N plant uptake and plant biomass. Four contrasting soil types from South Australia were used, and four rates of N were applied to the soil. DGT devices and KCl extraction were used at sowing to measure soil mineral N. These data were then compared with plant relative yield (Y R) and N uptake after harvesting the plants. Soil mineral N, as measured by both the DGT and KCl extraction techniques, demonstrated a significant positive correlation with Y R , with an R 2 value of 0.6; however, DGT-N extracted comparatively more nitrate (NO 3 –, >87 % of C N) than KCl-N (65 % of E N). Mineral N and NO 3 – extracted by both DGT and KCl significantly correlated with plant N uptake albeit this correlation was stronger for KCl (R 2 = 0.8) than DGT (R 2 = 0.6). The same parameters also positively and significantly correlated with Y R , however in this case, both correlations were similar and only modest (R 2 < 0.6 in all cases). These results are explained in terms of the differences between the pools of N accessed by these techniques and limitations related to soil N dynamics. In conclusion, KCl showed similar or better predictive ability for N uptake and yield response (Y R) in wheat compared to DGT across four Australian soils. Given its low cost and ease of application, KCl presents a competitive advantage in this study. [ABSTRACT FROM AUTHOR]

• We show a new index AWCI based on soil reservoir theory and the available water content. • New index focuses on soil water and considers crops and soil structure. • MODCYCLE model depicts soil water dynamics and AWCI index evaluate agricultural drought. • Available water content of the soil index in a typical North China Plain region is shown. • Drought data is provided for winter wheat as an example. Global climate change has led to an increase in the number of drought events. Agricultural droughts, which are influenced by crops, climate, and soil, are complex and challenging to identify. This study proposed a new index, the available water content of the soil index, based on the soil reservoir theory, which focuses on soil water and considers both crops and soil structure. We constructed the MODCYCLE model to depict soil water dynamics and evaluate agricultural drought by using the available water content of the soil index in a typical North China Plain region. The results showed that the soil in the western and southern regions was relatively dry and that the soil in the eastern and northern regions was humid. Drought occurred owing to the increased water demand during the critical growth period of winter wheat. Irrigation alleviated the drought. When the AWCI is greater than 0.6 in early April, the degree of drought is relatively mild. When the AWCI is less than 0.4, it is very easy to experience severe drought in mid-April.The central and eastern regions were susceptible to drought after mid-April, and the western region experienced drought until late May. Varying soil moisture, particle composition, irrigation, and precipitation conditions influenced the evolution of the drought. Enhancing soil moisture and timely irrigation before the critical growth period of winter wheat effectively prevented severe droughts in the region. The results provide guidance for regional drought monitoring and forecasting, water resource management, and scientific irrigation, effectively ensuring food security. [ABSTRACT FROM AUTHOR]

In the initial stages of restoring areas affected by rocky desertification, plant survival is strongly influenced by nitrogen nutrition. Mycorrhization is a unique type of inter-root engineering that improves nitrogen acquisition efficiency by plant roots. We selected potted mulberry trees inoculated, two dominant arbuscular mycorrhizal fungi (AMF) with Funneliformis mosseae (Fm) and Rhizophagus intraradices (Ri), to clarify the effects of AMF on the root nitrogen content of mulberry trees. Meanwhile, the key factors of soil nitrogen changes caused by AMF were analyzed, based on the primary role of soil nitrogen as the source of root nitrogen. Simultaneously, the potential of AMF to promote the acquisition of different forms of nitrogen by mulberry roots was investigated. Our findings indicate that the inoculation of mulberry plants with Fm and Ri, improved plant height and increased nitrogen accumulation in the roots and shoots. Additionally, AMF regulates nitrogen transformation, significantly increasing soil nitrate nitrogen (NO 3 −-N) and dissolved organic nitrogen (DON) levels. The results indicated that soil NH 4 +-N, NO 3 −-N, and DON contributed to the observed changes in root nitrogen accumulation. The largest contribution (22.0 %) to the overall effect size was made by NO 3 −-N. AMF stimulated soil microbial activity and significantly increased soil glomalin-related soil protein (GRSP), enzyme activity, and soil microbial biomass (SMB). Urease activity and microbial biomass carbon (MBC) both increased exponentially by 118.7 % and 115.2 %, respectively. Higher GRSP, enzyme activity, and SMB were positively correlated with changes in soil nitrogen patterns, and GRSP had the most significant effect on changes in the soil nitrogen dynamics. Our study confirmed that inoculation with AMF not only regulates soil nitrogen dynamics but also diversifies plant nitrogen sources. This is achieved by increasing plant growth and enhancing soil microbial activity. Ultimately, this enhances plant root nitrogen nutrition. Therefore, AMF promote root nitrogen accumulation and enhance root nitrogen uptake through GRSP-regulated soil nitrogen, providing a theoretical basis for the management of rocky desertification. [Display omitted] [ABSTRACT FROM AUTHOR]

Biochar amendment can improve soil phosphorus (P) availability, yet the influence of microbial community structure, especially certain keystone taxa on P dynamics remains uncertain. A pot experiment was conducted on a highly weathered Ferralsol to investigate how the amendment with biochar and P-fertilizer (CK, no biochar and P addition; PP, 30 kg P ha−1 addition; BC, 4 % biochar addition and BP, 30 kg P ha−1 combined with 4 % biochar addition) affect soybean (Glycine max (L.) cv. Huaxia-9) P uptake, soil P dynamics and its association with bacterial community structure and keystone taxa. The biochar-amended treatments (BC and BP) led to a 50–130 % increase in P uptake and a ten-fold rise in labile P proportion compared to treatments without biochar (CK and PP). This could be associated with the incorporation of P from biochar, as well as the altered soil P availability by elevated soil pH, soil organic carbon (SOC), microbial biomass P and alkaline phosphatase activity. Furthermore, biochar amendments altered bacterial community composition by increasing the relative abundance of Gemmatimonadetes, Bacteroidetes and Verrucomicrobia phylum by over three-fold, while decreasing the relative abundance of Chloroflexi and Acidobacteria phylum by over 50 %, compared to the non-biochar treatments. Additionally, the elevated C:P ratio following biochar amendment played a dominant role in shaping the keystone taxa, which was identified as the primarily microbial predictor of soil labile P. Specifically, biochar amendment increased microbial network complexity, inducing a shift in keystone taxa from oligotrophs to copiotrophs, such as Rhizobiales, Sphingomonadales and Rhodospirillales, which are wildly recognized for their roles in soil P mobilization. Taken together, our findings suggested that biochar-induced shift in keystone taxa is one of the major predictors of soil P dynamics, highlighting the potential of harnessing specific keystone taxa for improving soil P availability. • The elevated pH, SOC, MBP and phosphatase by biochar affected soil P dynamics. • Biochar amendment increased microbial network complexity and organization. • Biochar amendments shifted keystone taxa from oligotrophs to copiotrophs. • The shift in putative keystone taxa was the primarily predictor of soil labile P. [ABSTRACT FROM AUTHOR]

Increased nitrogen (N) and phosphorus (P) inputs to terrestrial ecosystems, which are caused by human activities and atmospheric deposition, significantly affect soil nutrient cycling. However, information on the variations of fertilization treatments on the nutrient utilization and carbon (C) storage mechanisms in alpine meadow soil aggregates is limited. Here, we investigated the responses of microbial nutrient utilization and C storage dynamics in soil aggregates to nine-year fertilization (N, P, and NP addition) in an alpine meadow. The results demonstrated that nine-year fertilization did not affect soil aggregate stability, however, they promoted soil organic C (SOC), total N (TN), and total P (TP) accumulation and altered the microbial nutrient-limitation patterns of soil aggregates in the alpine meadow. Compared to N and NP treatments, the P addition was optimal for improving soil aggregate-associated C storage and soil C pool management index (CMI). Furthermore, the NP treatment significantly exacerbated the microbial C limitation and microbial P limitation was significantly greater with N addition alone than with P addition alone, which was consistent with the resource allocation theory. The enhanced microbial carbon limitation caused by fertilization had no significant impact on soil aggregate-associated C storage and CMI. Simultaneously, soil nutrients and enzyme activities increased with decreasing soil aggregate size. However, these changes did not affect the microbial nutrient limitation patterns and CMI, which may have been related to the stronger nutrient protection ability of microaggregates. Therefore, nine years of fertilization increased the soil aggregate-associated C sink functions and affected soil microbial nutrient-limitation patterns by altering the soil C, N and P stoichiometry in the alpine meadow. These findings provide technical support for future alpine meadow management. • Fertilization improved soil aggregate C pools, and P treatment performed optimally. • Fertilization and soil aggregate size altered microbial nutrient limitation patterns. • Enhanced microbial C limitation from fertilization didn't affect C storage and CMI. • Aggregate size, not fertilization, affected the stability of soil aggregate C pools. [ABSTRACT FROM AUTHOR]

The amount of water in the soil has an impact on how well plants absorb nutrients. As a result, both above and below-the-surface water dynamics have an effect on crop growth. The quality of the soil and its mechanical qualities can be significantly altered by both an excess or a lack of water, which could make food production unsustainable. This study deals with the development of a precision farming approach to irrigation that considers the topographical features of the arable land and incorporates its morphological properties. The prediction of the water movement in the topsoil layer is an essential element of this strategy, which uses an agent-based model to describe the soil dynamics and the impact of irrigation and exploits a model predictive control (MPC) to optimize water usage. As a case study, the municipality of Samacá in the department of Boyacá, Colombia, is considered. • An agent-based model describes crop–soil dynamics and irrigation. • Nonlinear model predictive control allows deployment of optimal irrigation policies. • Satellite and aerial imaging can support model development and field measurements. [ABSTRACT FROM AUTHOR]

Water scarcity is a problem that affects agricultural production around the world. Increasing forage production in the semiarid region is necessary to maintain animal production, and consequently food security. Different agronomic management can improve growth and productivity responses and the water-economic indexes of the crop. Therefore, this study aimed to evaluate how the management of density and orientation of forage cactus plantations modify the morphophysiological indices, phenophases, cutting moment, productivity, soil water balance, and water-economic indicators in a semiarid environment. The study was carried out during two harvests (2020–2021 and 2021–2022) in the Brazilian semiarid region. Three experiments were conducted with the 'Orelha de Elefante Mexicana' clone under a randomized block design and four replications. Two experiments were composed of five planting densities (100,000, 50,000, 33,000, 25,000, and 20,000 plants ha−1) modified by the spacing between plants (0.10, 0.20, 0.30, 0.40, and 0.50 m with a fixed distance of 1.00 m between rows), the first with East-West (EW) orientation and the second with North-South (NS) orientation. The third experiment presented four planting densities (50,000, 40,000, 33,000, and 28,571 plants ha−1) modified by the distance between rows (1.00, 1.25, 1.50, and 1.75 m with a fixed distance of 0.20 m between plants). Biometric and biomass data were used to determine morphophysiological indices, delimitation of phenophases, ideal cutting moment, and fresh matter (FM) and dry matter (DM) productivity. The soil water balance was carried out using soil moisture readings and the physical-water properties, and the crop's water-economic indices were calculated. In general, morphophysiological indices, phenophases, and cutting moments were affected by densities (p<0.05). DM productivity was 16 % higher in the EW orientation (27.7 Mg ha−1) compared to the NS orientation. The highest planting density (100,000 plants ha−1) in the 1.00 × 0.10 m arrangement presented the highest averages of FM and DM of the cycles, being 401.5 and 32.4 Mg ha−1 orientation EW and 420.8 and 29.5 Mg ha−1 orientation NS. Density of 50,000 plants ha−1 in the 1.00 × 0.20 m arrangement (265.5 and 23.5 Mg ha−1 of FM and DM, respectively). This same behavior occurred for water and economic indices. Therefore, higher densities in forage cactus cultivation (100,000 plants ha−1 in the East-West planting orientation and 50,000 plants ha−1) must be adopted to enhance forage production in semiarid regions. [Display omitted] • Morphophysiological indices of forage cactus by densities and cultivation orientation. • Higher cropping densities have high forage production in arid and semiarid regions. • Higher crop densities present greater water-economic efficiency. • The soil-plant relationship was influenced by different experimental arrangements. [ABSTRACT FROM AUTHOR]

Long-term farming system experiments with comprehensive soil, plant and meteorological data combined with well-validated dynamic farming system models are a powerful combination to evaluate the production and environmental implications of novel innovations in agriculture. A current deficiency is the lack of adequate comprehensive validations for long term crop sequences that capture the dynamics of soil and crop responses without resetting soil conditions, especially for soil mineral nitrogen (Min-N). This reduces confidence in the outcome of scenario analyses for proposed improvements in productivity and sustainability given the central role played by nitrogen (N) dynamics in both processes. We used data from a 30-year long-term experiment (LTE) to validate the APSIM model and achieved excellent predictions for soil and crop responses including the dynamics of Min-N without resetting. A critical step was to ensure that the parameters required for the pools of soil organic matter matched those measured at the site over the full rooting depth (1.6 m) rather than limiting measured values to surface layers and relying on default parameters in deeper layers. In subsequent scenario analyses of agronomic innovations including fallow weed control, earlier sowing and improved N fertiliser strategies, the validated model predicted potential increases in average annual productivity of 1.2 t ha-1 (30%), WUE of 2.0 kg ha-1 mm-1 (30%) and NUE of 13 kg kg-1 (21%) and reductions in average annual N leaching of 8 kg N ha-1 (-33%) and soil organic matter loss of 3.1 t ha-1 (31%) (0–10 cm) could be achieved with specific combinations of synergistic innovations previously investigated separately in shorter-term experiments. Our study represents a rare case of model validation capturing the dynamics of soil water, Min-N, biomass and grain yield in a long-term diverse crop sequence to provide confidence in scenario analyses of production and environmental consequences of agronomic innovations. LTEs provide a valuable resource for such validation, while conclusions drawn from simulation studies that lack comprehensive validation must be considered with caution. [Display omitted] • A rare case of model validation using a 30-year long-term experiment is presented. • Yield, biomass, soil water and N were accurately predicted without resetting. • Scenarios of improved weed, N and sowing time management were simulated. • Optimal agronomy was predicted to improve system productivity and efficiency by 30%. • Improved production efficiency was accompanied by reduced N leaching and soil C loss. [ABSTRACT FROM AUTHOR]

Irrigation is a vital measure for maintaining grassland productivity in arid and semi-arid regions. Grasslands typically have characteristics such as unclear boundaries, complex vegetation types, and relatively small irrigation amounts, making it challenging to extract irrigation information. Currently, research on extracting grassland irrigation information is scarce. This study proposes a method for extracting grassland irrigation information using high spatiotemporal resolution (30 m, 1 day) downscaled surface soil moisture data, combined with Landsat 8/9 and Sentinel 1/2 data. This method was applied to extract the irrigation area, timing, and frequency of grasslands in the Delingha Piedmont, northwestern China. The results showed that the overall classification accuracy of irrigated grassland was 93.43 %, and the kappa coefficient was 0.91, indicating high extraction accuracy. The average values of recall, precision, and F-score for irrigation timing and frequency were 82.54 %, 72.25 %, and 77.03 %, respectively, with most irrigation events accurately identified, indicating commendable overall efficacy. The combined use of multi-source remote sensing data is crucial for the extraction of grassland irrigation information. Among these, The high spatiotemporal resolution downscaled surface soil moisture data, by providing detailed spatiotemporal surface soil moisture dynamics, demonstrate a potent capacity for capturing irrigation events, thus effectively enhancing the accuracy of grassland irrigation data extraction. • Downscaled 1 km SSM data to 30 m using comprehensive downscaling factors for high-resolution accuracy. • GIDSM method effectively identified grassland irrigation timing, frequency, and distribution. • High-resolution SSM data improved accuracy by reducing confusion with other land types. • Study demonstrated potential of SSM data for detecting irrigation in arid regions. [ABSTRACT FROM AUTHOR]

The recent global population explosion has increased people's food demand. To meet this demand, huge amounts of nitrogen (N) fertilizer have been applied in the worldwide. However, ammonia (NH 3) volatilization is one of the primary factors of N loss from soil after N application causing decrease crop N utilization efficiency and productivity. Incubation experiments were conducted on an acidic clayey soil with two different N sources (urea and anaerobic digestion effluent; ADE), two differently-produced biochars, and three biochar application rates (0%, 0.25%, and 1.0% w/w). Ammonia volatilization was lower from urea (14.0–23.5 mg N kg−1) and ADE (11.3–21.0 mg N kg−1) with biochar application than those without biochar (40.1 and 26.2 mg N kg−1 from urea and ADE alone, respectively). Biochar application significantly mitigated volatilization and reduction percentages for urea and ADE were 40%–64% and 18%–55%, respectively. 1.0% biochar application mitigated volatilization significantly compared to 0.25% application regardless of N source and biochar types. Possible mechanism for volatilization mitigation for urea and ADE were increased N immobilization by soil microorganisms and accelerated net nitrification rate due to increased soil nitrifying bacteria, respectively. Overall, our results clarified different mechanisms for N volatilization mitigation from different (inorganic vs. organic) N sources with biochar application. [Display omitted] • Biochar mitigated NH 3 volatilization by 64% from urea and 55% from ADE. • Biochar application rate affected more mitigation than biochar properties. • Mitigation mechanism included immobilization with urea and nitrification with ADE. [ABSTRACT FROM AUTHOR]

• A 3D dynamic torsional impedance solution is derived for offshore large-diameter pipe piles. • The impedances across the pile cross-section vary with the pile dimension and soil plug strength. • One-dimensional rod theory overestimates the overall impedance of the cross-section. • For common-size pipe piles, the impedance decreases from the pile outer radius to the inner radius. • For large-diameter pipe piles, the soil plug could play a dominant role in resisting torsional vibrations. Wind-induced or current-induced torsional vibration is a long-neglected issue for offshore engineering (e.g., offshore wind turbines, offshore oil platforms, etc.). As the dimension of the pipe pile implemented offshore increases dramatically, the one-dimensional rod theory can no longer precisely compute the dynamic torsional impedance. This paper proposes a novel 3D torsional soil-pile interaction model and derives the corresponding analytical solution for the 3D dynamic torsional impedance at the pile cross-section with the adoption of the Laplace transform, variable separation, and impedance transfer method. The solution is then validated by comparisons against some widely-accepted existing solutions. The main conclusions of this study can be drawn as follows: (1). Classic one-dimensional theory overestimates the impedance of the pipe pile, which could result in severe disasters if the dynamic design is radical; (2). Even for small diameter pipe piles, the impedance would vary in the radial direction at the pile cross-section. Usually, the impedance at the outer radius would be slightly larger than that at the inner radius; (3). For large-diameter pipe piles or pipe piles with high-strength soil plugs, the most significant impedance could appear at the inner radius, indicating the resistance provided by the soil plugs can not be overlooked for large-diameter pipe piles. [ABSTRACT FROM AUTHOR]