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The Himalayas significantly impact local and regional hydro-sedimentary processes and weathering rates. Utilizing geomorphometric anomalies offers insights into the connections between topographic factors and rates of cation weathering and sedimentary flux. An empirical model RS-GIS tool was used to compute the runoff and weathering rates of the basin. The 6th-order Lolab River with 451 different lower-order streams is dominated by dendritic to semi-dendritic draining patterns with the presence of steep slopes. The linear aspects of the basin showed the drainage pattern is influenced by geological and lithological factors. Additionally, other parameters such as rotundity factor, circulation factor, compactness coefficient, and elongation ratio indicate an elongated shape, reduced peak flow, and a complex structure. The significant reduction in Runoff (Q) and Sediment Production Rate (SPR) within the Lolab basin, measuring 4.61 sq km-cm/sq km and 0.17 ha-m/100-sq km/year respectively, suggests minimal runoff and reduced soil erosion. These findings can provide valuable information about weathering, erosion, and sediment delivery processes. This data helps understand how environmental changes and natural hazards affect the fragile Himalayan landscape and aids in regional land management decisions for sustainable land use policies. [ABSTRACT FROM AUTHOR]

Introduction: Groundcover management plays a crucial role in improving water retention and soil nutrition in orchard systems, thereby preventing environmental constrains by non-point source pollution. However, effectiveness of groundcover management in citrus orchards developed on sloping farmland with eroded purple soil has not been studied in detail. In particular, information on the soil nutrient losses, e.g. , nitrogen (N) and phosphorus (P), through interflow and its effects on growth and nutrition of citrus plants has not been reported. Methods: The present study evaluated the effects of different cover crops, i.e. , Lolium perenne L. (Lolium), Vicia villosa Roth (Vicia) and Orychophragmus violaceus (Ory), on nutrition and growth of citrus trees as well as water, soil and nutrient retention in an orchard developed in sloping farmland during two consecutive years. Results and discussion: The results show that the groundcover species Lolium and Vicia mediated nursing effects on nutrition and growth of citrus trees. These nursing effects included enhanced foliar levels of carbon(C), N and P as well as increased tree height, stem diameter, and crown width. Groundcover management generally reduced the annual surface runoff, interflow, soil loss, total N loss and total P loss. Among the cover crop species studied, Lolium and Vicia were overall more efficient than Ory in this context. Lolium reduced the average annual total loss of N and P by 42.53% and 49.23%, respectively, compared with clean tillage. The estimated annual reduction potentials of soil, N and P losses in Southwestern China were 16.3, 3.4 and 8.5 million tons yr-1, respectively. Obviously, Lolium and Vicia provide highly beneficial ground coverage on sloping farmland and, thus, can be used for future sustainable development of citrus orchards. [ABSTRACT FROM AUTHOR]

The productivity of olive in the northwestern coastal zone of Egypt is significantly constrained by drought and low organic matter in the soil. This study addresses these challenges by exploring the synergistic effects of olive mill wastes (OMW) application and micro-catchment water harvesting techniques on soil properties, runoff, moisture storage, and rainwater harvesting efficiency. Field experiments were conducted over two winter seasons, employing different micro-catchment structures (semi-circular and triangular bunds) and OMW applications. The results revealed that the integration of semi-circular bunds with OMW application (T4) substantially increased rainwater harvesting efficiency by 67.7% and 46.4% in the first and second seasons, respectively. Additionally, T4 and T5 exhibited reduced runoff by 47.8% and 41.3% in the first season and 49.4% and 38.9% in the second season, respectively. T4 significantly enhanced soil organic matter, soil macronutrients (N, P, and K), and micronutrients (Fe, Mn, Zn, and Cu) compared to the control (T1). The study highlights the effectiveness of T4 in improving soil moisture, reducing soil erosion, and enhancing soil fertility. This integrated approach involving OMW application within a semi-circular bund as a water harvesting system proves to be a promising strategy for sustainable olive cultivation in arid conditions. [ABSTRACT FROM AUTHOR]

Enhancing terrestrial carbon (C) stock through ecological restoration, one of the prominent approaches for natural climate solutions, is conventionally considered to be achieved through an ecological pathway, i.e., increased plant C uptake. By conducting a comprehensive regional survey of 4279 1 × 1 m² plots at 517 sites across China's drylands and a 13-y manipulative experiment in a semiarid grassland within the same region, we show that greater soil and ecosystem C stocks in restored than degraded lands result predominantly from decreased surface soil C loss via suppressed wind erosion. This biophysical pathway is always overlooked in model evaluation of land-based C mitigation strategies. Surprisingly, stimulated plant growth plays a minor role in regulating C stocks under ecological restoration. In addition, the overall enhancement of C stocks in the restored lands increases with both initial degradation intensity and restoration duration. At the national scale, the rate of soil C accumulation (7.87 Tg C y-1) due to reduced wind erosion and surface soil C loss under dryland restoration is equal to 38.8% of afforestation and 56.2% of forest protection in China. Incorporating this unique but largely missed biophysical C-conserving mechanism into land surface models will greatly improve global assessments of the potential of land restoration for mitigating climate change. [ABSTRACT FROM AUTHOR]

Past nuclear weapons testing (NWT) and nuclear power plant (NPP) accidents have resulted in the ubiquitous deposition of radionuclides in the environment. While radionuclide contamination of the environment is associated with concerning health risks, these fallout radionuclides (FRNs) are considered the privileged markers ("golden spikes") of the Anthropocene stratigraphic layers. Their deposition in the 1950s coincided with the "Great Acceleration", which is characterized by large-scale shifts in the Earth's systems, including increased land-use change and soil degradation. Among the FRNs deposited globally, 137Cs has been the most commonly used to assess soil erosion and/or the chronology of sediment deposition, and 239+240Pu is an emerging soil erosion tracer and chronological marker increasingly used due to a number of advantages. We compiled 137Cs and 239+240Pu data published from undisturbed (so called "reference") soils in the Equatorial and Southern Hemisphere regions to build a database under the AVATAR Project ("A reVised dATing framework for quantifying geomorphological processes during the Anthropocene"). Using this database, named the AVATAR-Soils Database, we determined the distributions of 137Cs and 239+240Pu inventories in Equatorial and Southern Hemisphere soils, along with the relative contributions of different fallout nuclear weapon sources by analysing their isotopic ratios. Additionally, we demonstrated how the database can be used to identify the environmental factors that influence the distributions of 137Cs and 239+240Pu in reference soils by applying a machine-learning algorithm. Our metanalysis revealed that high 137Cs and 239+240Pu inventories were recorded near the equator and within the 20–40° S latitudinal bands, which coincide with the location of multiple NWT. The 240Pu/239Pu atomic ratios suggest that sources other than the global fallout (primarily from US and USSR weapon testing with a 240Pu/239Pu atomic ratio of ~ 0.18) contributed to the reference inventories in the Southern Hemisphere. These additional sources have been relatively neglected so far. On average, the French fallout contributed ~20 % to the reference soil 239+240Pu inventories in South America and up to 70 % in French Polynesia. In contrast, the British fallout contributed ~27 % to the reference soil 239+240Pu inventories in the rest of Oceania. Our machine-learning algorithm identified precipitation of the coldest quarter, longitude, and latitude as the strongest predictors of 137Cs inventory. For 239+240Pu inventory, mean diurnal temperature range, temperature annual range, and precipitation of the driest quarter were the strongest predictors. Altogether, these findings demonstrate the potential of the AVATAR-Soils Database as resource for improving our understanding of the distribution and sources of 137Cs and 239+240Pu in Equatorial and Southern Hemisphere soils and refining their application as tools in various Earth Science research. The AVATAR-Soils Database may be accessed at https://doi.org/10.5281/zenodo.14008220 (Dicen et al., 2024). [ABSTRACT FROM AUTHOR]

Soil erosion is a major environmental problem with detrimental consequences. In this article, we present a detailed study on the analysis of soil water erosion using machine learning (ML) techniques in the Oued Ourika watershed in Morocco. We collected data on various factors that may influence the mechanisms of soil water erosion events. Subsequently, we developed machine learning models to predict the potential for soil water erosion based on these factors. Finally, field studies were conducted compared to the obtained results. A historical inventory of water erosion has been created through fieldwork, satellite imagery, and historical water erosion events. Models were constructed using the training data, and their performance and accuracy in predicting susceptibility to water erosion were evaluated using the validation data. This data division allowed for a fair assessment of the models’ ability to make accurate predictions. Using a Geographic Information System (GIS) and programming in the R language, four supervised machine learning algorithms were applied, including k-nearest neighbor (KNN), extreme gradient boosting (XGB), random forest (RF), and naive bayes (NB). The results show that the NB model exhibited the highest accuracy in predicting and evaluating the effectiveness of these algorithms in forecasting susceptibility to water erosion in the study area. Accuracy was assessed using the area under the curve (AUC) metric, with an AUC of 98%. The XGB algorithm had an AUC of 96%, followed by RF with an AUC of 87%, and KNN with an AUC of 84%. Thus, the Naive Bayes model proved to be the best for determining susceptibility to water erosion in the study area. The analysis of water erosion reveals that 43% of the total area of the Oued Ourika watershed is exposed to a high to very high risk of erosion in the Ourika region. These findings can assist regional and local authorities in reducing the risk of water erosion and implementing effective measures to prevent potential damages. The goal is to protect the communities and infrastructure located along the course of the Ourika. Overall analysis of natural disasters, the accuracy of the results heavily depends on the availability and quality of data, which must encompass an adequate number of parameters. [ABSTRACT FROM AUTHOR]

Mercury (Hg) is a persistent pollutant highly bioaccumulated in the aquatic environment through the food chain reaching high concentration levels in the tissues of predator fishes. Among the relevant sources of anthropogenic mercury emissions in Latin America and the Caribbean (LAC), mining is one of the most important along with soil erosion due to deforestation and agricultural activities where pesticides are intensively used. Several reports have demonstrated an association between a fish-based diet with elevated Hg levels in the blood and neurotoxic effects in humans. In this systematic review with quantitative analysis data from 92 articles were compiled, providing evidence of Hg concentration in fishes that are commonly consumed in LAC. An assessment was conducted using three indices for health risk: the Minamata Initial Assessment (MIA), the Target Hazard Quotient (THQ), and the Meals per Week (MPW) index. Of the 410 fish species studied, 5.4% had concentrations above 0.95 μg g−1 of wet weight (ww), which is the recommended limit for Total Hg (THg) ingestion through fish consumption according to the MIA index, regardless of the water habitat (i.e., marine or freshwater). Additionally, the Target Hazard Quotient (THQ) calculation indicated high-risk values (THQ ≥ 1) in 15 out of the 19 countries studied, and very high-risk values (THQ ≥ 10) were obtained from Hg concentrations measured in 5 fish species inhabiting watersheds in Trinidad and Tobago, Suriname and Peru. Finally, recommendations on fish consumption were made based on the MPW index. This study reveals the need for updated biomonitoring studies of Hg concentrations in fish to perform more accurate human health risk analyses. [ABSTRACT FROM AUTHOR]

Soil erosion is a hazard in every part of the world. The small-scale farmers often grapple with low agricultural production and food insecurity. This study was conducted to estimate soil loss in response to land use/cover change in 1990, 2000, 2010, and 2020 around Ghibe hydroelectric III dam in Southern Ethiopia. The Revised Universal Soil Loss Equation (RUSLE) model was applied using a geographic information system (GIS). Digital elevation model with 30 m to determine topographic factor and supportive practice (P) factor, rainfall from the National Meteorological Institute to calculate the erosivity (R) factor, a digital soil map of the world for erodibility (K) factor, and Landsat 5TM images of 1990, 2000, 2010, and the Landsat 8 OLI of 2020 to determine trends of land use/cover change and the cover management (C) factor were employed. The raster layers of topography, cover management, rainfall erosivity, soil erodibility, and conservation techniques were processed and multiplied using the GIS platform. The overall accuracy of supervised classification was 89.89. The results showed that the percentage of cropland and built-up areas increased by 11.93 and 32.44%, respectively throughout the three study periods. Conversely, the proportion of forest land, grassland, bare land, and bushland declined by 8.2, 9.3, 10.13, 8.6%, respectively. The average annual soil loss rates increased from 30.95 t ha−1 yr−1 in 1990 to 43.85 t ha−1 yr−1in 2020. This is significantly higher than the maximum threshold rate of erosion for Ethiopian highlands (11 t ha−1 yr−1). The local government officers, non-governmental organizations, and farmers who are trained should strengthen watershed management techniques. [ABSTRACT FROM AUTHOR]

Global food security depends on agricultural development, yet excessive fertilizer and pesticide usage is harmful to the environment. These substances have a role in human health problems, environmental changes, and erosion of the soil. Although p‐nitrophenol, an organic pollutant and other organophosphorous compounds are utilised in agriculture, their usage raises major health and environmental issues. These synthetic pesticides are quite effective at getting rid of pests, but they have also been linked to serious health problems for people and animals, degraded soil, and contaminated water. One typical persistent pollutant present in industrial wastewater is the organic pollutant, which is produced by organophosphorous compounds. The primary objective of this work is to use Cu@ZIF for photoreduction of p‐nitrophenol (PNP). A UV‐visible spectrophotometer test revealed that the deterioration peak after 60 mins. An analyzer for total organic carbon (TOC) was utilised to assess the PNP mineralization. The catalyst remained same and continued in the same behaviour even after four cycles. This study evaluated the acute toxicity of PNP on the development of early‐stage zebrafish, paying particular attention to the embryonic developmental deformities. The technique of photocatalytic decontamination is safe for the environment, financially practical, and technically achievable. [ABSTRACT FROM AUTHOR]

Increased environmental nitrogen (N) losses have prompted the use of enhanced efficiency nitrogen fertilizers, including nitrification inhibitors. However, the comparative effects of nitrification inhibitors with conventional nitrogen fertilizers and herbicides on soil nitrification and nitrogen losses remain poorly understood. This study evaluated the impact of a nitrification inhibitor (Instinct NXTGEN), two nitrogen sources (broadcast urea vs. injected aqueous ammonia), and a preemergence herbicide (Acuron) on (1) soil nitrification through a 25‐day soil incubation experiment and (2) NH3 volatilization, NO3‐N leaching, and N2O‐N emissions through a 31‐day soil column study in loamy sand soil. In both experiments, treatments included combinations of nitrification inhibitor versus no inhibitor, two nitrogen sources, and preemergence herbicide versus no herbicide. Results revealed that nitrogen source significantly influenced nitrification, with injected aqueous ammonia reducing nitrification by 33% compared to surface broadcast urea. Nitrification inhibitors and herbicide had no effect on soil nitrification. Injected aqueous ammonia reduced NH3 volatilization by 87% compared to surface broadcast urea, but the effect of the nitrification inhibitor on NH3 volatilization was inconsistent across both nitrogen sources. Injected aqueous ammonia led to 39% higher cumulative nitrogen (NO3‐N + NH4‐N) leaching than urea, while the nitrification inhibitor had an inconsistent effect on NO3‐N leaching across both nitrogen sources. No significant differences in N2O‐N emissions were observed among treatments, and the herbicide had no effect on any measured parameters. These findings suggest that nitrogen source plays a more critical role in regulating soil nitrogen losses than nitrification inhibitors or herbicides. Core Ideas: Nitrogen sources had a greater impact on soil nitrification and fertilizer nitrogen recovery than nitrification inhibitors and herbicides.Injected aqueous ammonia reduced NH3 volatilization by 87% compared to surface broadcast urea.Injected aqueous ammonia resulted in 39% higher cumulative nitrogen (NO3‐N + NH4‐N) leaching than surface broadcast urea.The response of the nitrification inhibitor to N losses was inconsistent across urea and aqueous ammonia.Herbicides had no significant effect on soil nitrification or nitrogen losses. [ABSTRACT FROM AUTHOR]

The Zagora province in southern Morocco, characterized by its fragile Oasis-mountain-desert ecosystem, faces increasing threats from climate change. While the impacts of climate change on arid regions are widely acknowledged, location-specific studies analyzing future projections remain scarce, hindering the development of effective adaptation strategies. This study addresses this gap by examining historical temperature and precipitation trends in Zagora province from 1981 to 2021 and projecting their evolution to 2050 using time series modeling. An exponential trend model, demonstrating a high goodness-of-fit (R2 = 0.825), was identified as most effective for temperature forecasting, projecting a significant increase in mean annual temperature of + 1.1 °C (with a 95% confidence interval ranging from − 0.16 °C to + 2.45 °C) and in maximum temperature of + 1.65 °C (95% CI: +0.49 °C to + 2.82 °C) by 2050. An ARIMA (0,1,1) model with a constant best captured the historical precipitation patterns, revealing a projected increase in annual rainfall of 51.24 mm (95% CI: -25.59 mm to + 163.93 mm), potentially intensifying the risk of floods and soil erosion. These findings underscore a significant warming trend and a shift towards a more variable precipitation regime in the region. These projected changes, combined with a potential increase in rainfall intensity, threaten the sustainability of water resources, soil stability, and agricultural productivity in this already vulnerable region. This study provides essential quantitative data for informing adaptation decisions, guiding the implementation of effective strategies to preserve the Zagora Oasis ecosystem and the vital services it provides. [ABSTRACT FROM AUTHOR]

It is well known within the dam engineering profession that the potential for earthquake-induced cracking is a key consideration in the design and construction of dams. Transverse cracking of embankment dams is a major concern of engineers involved in dam safety management and commonly represents a potential failure mode for such dams. If transverse cracking extends below the reservoir level, it may lead to leakage from the reservoir, internal erosion of the embankment soils, and dam failure. Considerable effort has been made in the engineering profession during the last few decades to study the nature and effects of dam earthquake cracking and to develop design measures to mitigate its potential occurrence. However, few studies exist on earthquake-induced cracking of embankment dams, and the profession's ability to accurately predict its characteristics is limited. Thus, it seems useful to review key aspects of earthquake cracking of embankment dams and some of the lessons learned about cracking from the past performance of dams during earthquakes. This paper aims to fulfill this objective by providing an overview of the observed effects of earthquakes on embankment dams, discussing the potential for embankment dam failure by cracking, reviewing basic concepts about the mechanics of cracking in soils, discussing the analysis of embankment dam cracking in practice, and presenting two case histories of cracking of embankment dams. The case histories describe (1) the performance of Matahina dam during construction, reservoir filling, and the 1987 Edgecumbe earthquake in New Zealand and (2) the performance of Lenihan dam during the 1989 Loma Prieta earthquake in California and an analysis of the dam for that earthquake. [ABSTRACT FROM AUTHOR]

The original stress equilibrium state of the soil is destroyed after the excavation of the double-line shield tunnel, resulting in the settlement of the stratum above the tunnel and bringing adverse effects on the surface buildings and subsurface pipelines near the tunnel. The reasonable prediction of subsurface settlement is significant for protecting adjacent underground structures. The wave propagation model is introduced to describe the settlement mechanism of the stratum above the tunnel based on random medium theory, and the subsurface settlement model of single-line tunnel is derived through the Fourier transform. The disturbance influence factor of double-line tunnel is defined, and the corresponding settlement model is established. The three-dimensional subsurface settlement models of single-line and double-line shield tunnels are proposed by introducing the surface displacement release rate of palm surface and maximum slope of surface vertical settlement. The models are verified using monitoring data, and the effects of the parameters on the model are analyzed. [ABSTRACT FROM AUTHOR]

The variations in soil erosion significantly impact regional ecological security. Under rapid urbanisation, extensive ecological restoration and climate change, soil erosion development in the red soil region of southern China is ambiguous. Therefore, this study investigated the current (1980s–2020) and future (2050) erosion characteristics in a typical soil erosion control catchment (Changting section catchment) in this region by using the Cellular Automata Markov model and CMIP6 data to predict future scenarios and the Revised Universal Soil Loss Equation to estimate soil erosion. The results showed significant changes in the vegetation coverage of major land uses from 1980s to 2020, which was mainly caused by continuous soil and water conservation (SWC). The land use subtypes that were obtained by reclassifying land use based on the threshold of vegetation cover on soil erosion control, reflect a continuous transformation from those with poor SWC effectiveness to those with great SWC effectiveness. Therefore, the estimated soil erosion intensity continued to decrease from 1980s to 2020, and the contribution of land use/land cover (LULC) impacts ranged from 74%–195%. However, predictions of land use subtypes indicated that LULC may be stable after 2020; thus, soil erosion changed little when the climate was almost unchanged in 2050. Under climate change scenarios, soil erosion may increase by 111%–121%, and the contribution of precipitation impacts was 63%–66%. The major driving factor of soil erosion changes may shift from LULC to precipitation after 2020. Therefore, in the future, the potential for reducing soil erosion by vegetation restoration may be limited, and more engineering measures should be applied to address the erosion risk caused by climate changes. This study provides prospects for land use/land cover and soil erosion in the red soil region of southern China. [ABSTRACT FROM AUTHOR]

Soil erosion by water is a serious problem in Ethiopia, contributing to diminishing crop yields and food shortages. Apart from understanding the magnitude, risk, and spatial distribution of the problem, identifying erosion hotspot areas is essential for effectively reversing the problem. This study aims to identify erosion hotspots in the Gotu watershed, in northeastern Ethiopia, using the revised universal soil loss equation (RUSLE) and incorporating local farmers' perspectives to prioritize conservation efforts. The RUSLE model reveals that 29,744.3 metric tons of soil is lost annually from the Gotu watershed, with an average loss of 65.3 to t ha⁻1 year⁻1. The main contributing factors to soil erosion in the watershed include undulating topography, loss of plant cover, and continuous cultivation. The highest soil loss rates (> 80 t ha⁻1 year⁻1) were found in the western, northern, and southern parts of the watershed, where cultivation occurs on moderate to steep slopes with sparse vegetation cover. These areas should be prioritized for conservation interventions. Farmers identified poor crop yields and damaged conservation structures as key indicators of soil erosion prevalence in the watershed. Increasing farmer's understanding of soil erosion and the importance of soil and water conservation is essential for effectively controlling soil erosion and improving food security in the area. [ABSTRACT FROM AUTHOR]

Vineyards in Mediterranean areas suffer from significant soil degradation through erosion, due to rainfall and soil characteristics, as well as soil management practices. Previous studies pointed out the nutrient losses produced by erosion and the benefits that some management practices could have on reducing erosion. This research tried to evaluate the effect of events of different intensities and to assess whether the beneficial effect of compost amendment may pose a potential risk of nutrient loss and environmental pollution in particular under high-intensity events. The study compared soil and nutrient losses in compost-treated and non-treated vineyard soils after rainfall events of different intensities analyzed over 2 years in two vineyards. Runoff samples were collected by triplicate in treated and non-treated soils. Sediment and nitrogen and phosphorous concentrations in the runoff samples were analyzed. The results reveal a reduction in runoff rates and an increase in soil water content in compost-treated soils, which represents a benefit for rainfed vineyards. Both nitrogen and phosphorus losses depended on rainfall characteristics. Although for low intensities there were no significant differences in the amount of nutrient lost by runoff in both treated and non-treated soils, nitrogen and phosphorus losses were higher after high-intensity rainfall events in compost-treated soils. With the expected increase in high-intensity rainfall events associated with climate change in the Mediterranean region, organic amendments should be applied in several splits or incorporated into the soil to avoid increased nutrient loss to water bodies. [ABSTRACT FROM AUTHOR]

Land degradation is accelerating in the Himalayan ecosystem, resulting in the loss of soil nutrients due to severe erosion. Soil erosion presents a significant environmental challenge, resulting in both on-site and off-site consequences, such as reduced soil productivity and siltation in reservoirs. Soil erodibility (K factor), an inherent soil property, determines the susceptibility of soils to erosion. Sampling across hilly and mountainous terrain pose challenges due to its complex landscape. Despite these challenges, it is essential to study K factor variations in different land use/land cover types to comprehend the threat of erosion. Digital soil mapping offers an opportunity to overcome this limitation by providing spatial predictions of soil properties. The objective of our study is to map the spatial distribution of soil erodibility using the Random Forest (RF) model, a machine learning method based on sampled in situ soil data and environmental covariates. We collected 556 surface soil samples from the mountainous catchment (Tehri dam catchment) using the stratified random sampling approach. The model performed satisfactorily in both training (r2 = 0.91; RMSE = 0.00185) and testing (r2 = 0.45; RMSE = 0.00318) phases. Subsequently, we generated a digital map with a resolution of 12.5 m to depict the distribution of the K factor. Our analysis revealed that key environmental variables influencing the prediction of the K factor included geology, mean NDVI, and climatic factors. The average K factor value was estimated at 0.0304 and ranging from 0.0251 to 0.0400 t ha h ha−1 MJ−1 mm−1. A higher K factor was observed in the barren land (0.0344) primarily located in the higher and trans-Himalayan region of seasonally snow-covered areas. These areas typically feature young soils with weak soil formation and unstable soil aggregates. Subsequently cropland/cultivated soils (0.0307) exhibited higher K factor values due to the breakdown of soil aggregates by ploughing activities and exposing carbon to decomposition. The average K factor value of evergreen (0.0294) and deciduous (0.0295) forests were the lowest compared to other land use/land cover types indicating the role of forests in resisting soil erosion. By assessing and predicting soil erodibility, land planners and farmers can implement erosion control measures to protect soil health, prevent sedimentation in water bodies, and sustain agricultural productivity in the Himalayas. [ABSTRACT FROM AUTHOR]

Gravel soil faces significant engineering challenges such as leakage erosion and soil flow due to its complex composition and susceptibility to groundwater effects. This study integrates the entire machine learning process, including pre- and post-processing of images, WGAN implementation, and validation of hydraulic and morphological properties. Obtaining intact gravel soil samples is difficult and costly due to their erodible nature in the Li River, China. A μ-CT scanning series is employed to capture detailed images with three microstructural characteristics of gravel soil, forming the basis for training datasets using WGANs. This approach allows the generation of similar 3D realizations that replicate the microstructural characteristics and hydraulic behaviors of a prototype of gravel soils. Through computational fluid dynamics (CFD) simulations, the effectiveness of the realizations in hydraulic behavior within reconstructed porous structures is verified. This process indirectly validates the consistency between the realization′s microstructure and the prototype. This integrated methodology not only enhances understanding but also aids in the optimization of engineering designs and applications in geotechnical and materials science disciplines. [ABSTRACT FROM AUTHOR]

The Pisha sandstone area, situated in the upper and middle reaches of the Yellow River in China, is characterized by severe soil and water erosion, making it one of the most critical regions on the Loess Plateau. The rugged terrain and exposed bedrock complicate management efforts for this area, posing challenges for accurate forecasting using soil erosion models. Through an analysis of terrain, vegetation, and precipitation impacts on soil erosion, this study offers theoretical support for predicting soil erosion within the exposed Pisha sandstone area of the Loess Plateau. This has substantial implications for guiding water and soil conservation measures in this region. Focusing on China's exposed sandstone area within the Geqiugou watershed, temporal and spatial changes in vegetation cover and land use from 1990 to 2020 were analyzed. The result shows that, from 1990 to 2020, the grassland area has exhibited a consistent downward trend, with successive reductions of 64.86% to 59.46%. The area of low vegetation cover witnessed a significant decline of 59.29% in 2020 compared to that in 1990. The moderate erosion area decreased from 84.52 to 57.17 km2. The significant reduction in soil and water loss can be attributed to the expansion of forest and grassland areas, with the implementation of the Grain for Green project serving as a key policy driver for facilitating this expansion. This study provided a good example of combining rainfall with vegetation coverage to fast estimation soil erosion. A mathematical relationship between the vegetation rainfall coupling index (RV) and soil erosion was established with strong fitting effects, enabling estimation of the soil erosion volume under varying slope conditions within Pisha sandstone areas. The main focus of future soil and water conservation in the Pisha sandstone area should be on effectively managing the channel slope and minimizing exposed bedrock areas through a combination of slope cutting, the application of anticorrosive materials, and the implementation of artificial vegetation planting. [ABSTRACT FROM AUTHOR]

We estimate the implicit market price of soil erosion using quarterly data of 2824 agricultural farms traded in Uruguay between 2000 and 2014. A unique feature of our estimation is that we allow for possible spatial spillovers. We find evidence of a negative and statistically significant association between erosion and land values. On average, an additional loss of 1% of the original topsoil due to erosion is associated with a direct (own) decrease of.24% in the per‐hectare price of agricultural land (P‐value:.012, 95% CI: −.0042, −.0005). In 2023 dollars, this is equivalent to a decrease of USD 8.7 in the average price per hectare, or USD 1130 in the price of the average farm. In terms of tons of soil, the average value is $.24 a ton. Finally, considering the 50 km radius of our spatial model, the value of losing 1% of topsoil is $15.8 million. The value of our estimates is sensitive to our measure of erosion and our specification of the spatial‐temporal weighting matrix, but the statistical association is robust. [ABSTRACT FROM AUTHOR]

Gully erosion is a significant natural hazard and a form of soil erosion. This research aims to predict gully formation in the Kalshour basin, Sabzevar, Iran. Employing the Information Gain Ratio (IGR) index, we identified 13 key factors out of 22 for modeling, with elevation emerging as the most influential factor in gully formation. The study evaluated the performance of individual machine learning algorithms and ensemble algorithms, including the Functional Tree (FT) as the main classifier, Bagging (Bagg), AdaBoost (Ada), Rotation Forest (RoF), and Random Subspace (RSS). Using a data set of 400 gully and non‐gully points obtained through field investigations (70% for training and 30% for testing), the RoF model achieved an area under the curev (AUC) value of 0.99, indicating its high predictive ability for gully‐susceptible areas. Other algorithms also performed well (Ada: 0.90, FT: 0.92, RSS: 0.94, Bagg: 0.95). However, the RoF algorithm with the functional tree as the main classifier (RoF_FT) demonstrated the highest ability in gully classification and susceptibility mapping, enhancing the functional tree's performance. In addition to AUC, the RoF_FT model achieved an F1 score of 0.89 and an MCC of 0.78 on the validation set, indicating a high balance between precision and recall, and a strong correlation between predicted and actual classes, respectively. Similarly, other models showed robust performance with high F1 scores and MCC values, but the RoF_FT model consistently outperformed them, underscoring its robustness and reliability. The resulting gully erosion‐susceptibility map can be valuable for decision‐makers and local managers in soil conservation and minimizing damages. Implementing proactive measures based on these findings can contribute to sustainable land management practices in the Kalshour basin. RecommendationsGully erosion threat: Gully erosion poses a significant threat to soil, with far‐reaching environmental consequences.Predictive modeling: This research focuses on predicting gully formation in the Kalshour basin, Sabzevar, Iran, using advanced machine learning algorithms.Key findings for decision‐makers: The study evaluates the performance of various machine learning algorithms and ensemble algorithms, with the Functional Tree serving as the main classifier. This not only enhances our ability to predict gully formation but also provides a valuable tool for decision‐makers and local managers in soil conservation.Impact on sustainable land management: By offering a gully erosion‐susceptibility map, the research empowers decision‐makers to implement proactive measures, minimizing damage and contributing to sustainable land management practices.Interdisciplinary approach: The study's combination of geospatial analysis, machine learning, and soil conservation aligns with the journal's mission to advance understanding in environmental modeling. [ABSTRACT FROM AUTHOR]

The article "Correction to 'Object-Based Image Analysis (OBIA)-based gully erosion dynamics, sediment loading rate and sediment yield study in Lake Hawassa Subbasin, Ethiopia'" discusses the significant environmental issue of gully erosion in the Lake Hawassa Subbasin. The study aims to map and analyze changes in gully erosion, quantify sediment loading rates, and determine sediment yields using Object Based Image Analysis (OBIA) with high-resolution satellite images. The results show a rapid increase in gully extent between 2011 and 2020, impacting 5.53% of the subbasin area and leading to significant sediment loading into the lake. The study highlights the importance of addressing gully erosion to prevent further siltation and loss of the lake's storage capacity. [Extracted from the article]

Phosphorus (P) is an important soil element for sustaining plant growth and the integrity of terrestrial ecosystems, and the soil P cycle is strongly influenced by climate change and agricultural activities. However, little is known about how soil P has evolved with climate change and intensive agriculture at mid‐high latitudes, where the soil P cycle is sensitive to climate change. To answer this question, an ecohydrological model (EcoHAT‐P) driven by remote sensing data was used in this study to calculate soil P concentration and loss and was calibrated and validated using 272 soil samples collected in the Sanjiang Plain, a typical mid‐high latitude region with a long history of strong agricultural activity. Soil P concentration and loss, and plant uptake of soil P, were analyzed for the years 2000–2019 and 2020–2040. The results showed that soil total P, soil P loss, and plant P uptake all increased under intensive agriculture. The soil P cycle at mid‐high latitudes was more sensitive to temperature than to precipitation. Increased temperature would increase soil P loss and plant P uptake by 93.94% and 8.16%, respectively, and soil legacy P from intensive agriculture would become the main source even if external P inputs were eliminated. The results highlight the evolution of soil P transport at mid‐high latitudes and clarify the response of soil P cycle to climate change under intensive agriculture. [ABSTRACT FROM AUTHOR]

Soil bioengineering has been leveraged for controlling shallow landslides and soil erosion. Acacia mangium Willd. species is widely used for soil bioengineering, but its root properties have not been extensively investigated. This study aimed to measure the various properties (i.e., morphological traits, biomechanical properties, chemical composition and root reinforcement) for establishing roots of A. mangium Willd. species through a series of laboratory experiments (i.e., rhizobox observation, uniaxial tensile test, direct shear and volumetric water content and suction monitoring). The results underscored the rapid growth (i.e., 0.43 ± 0.01 cm/day) and highlighted variations in "side" root area ratios of A. mangium Willd. species with depth. Root orientation also demonstrated a significant correlation with root diameter following a linear model (p < 0.05, R2 = 0.39). At the early‐stage establishment (28 weeks), A. mangium Willd. roots exhibited the tensile strength, Young's modulus and mechanical reinforcement of 10.18 ± 0.62 MPa, 325.18 ± 21.72 MPa and 3.15 kPa, respectively. The presence of roots was found to increase the soil suction, air‐entry value and saturated water content of lateritic soil by improving the soil‐water characteristic curve. This work elucidated the root properties of A. mangium Willd. during the early‐stage establishment, raising caution for the design of slope‐stabilisation projects using soil bioengineering, especially during the initial phase of projects. [ABSTRACT FROM AUTHOR]

Soil erosion is a global environmental issue, and sediment transport capacity (Tc) is critical for developing soil erosion models. This study conducted flume drainage experiments at six flow discharges (0.15, 0.25, 0.35, 0.45, 0.55, and 0.65 L s−1) and eight slope gradients (1.5, 3.0, 4.5, 6.0, 7.5, 9.0, 10.5, and 12.0°) to investigate how the Tc of gentle slopes in the northeastern hilly region of China and water erosion factors are related and to establish a Tc model of overland flow. The study demonstrated a power–law relationship between Tc, flow discharge, and slope gradient, as evidenced by a high coefficient of determination (R2; 0.94) and Nash–Sutcliffe efficiency (NSE; 0.92) values. Additionally, there was a positive correlation between Tc and average flow velocity, with R2 and NSE values of 0.86 and 0.84, respectively. Among the hydrodynamic parameters tested, the average flow velocity was determined to be the most effective Tc predictor, surpassing stream power (R2 > 0.7, NSE > 0.7), shear stress (R2 > 0.6, NSE > 0.6), and unit stream power (R2 < 0.5, NSE < 0.5). These findings lay the foundation for developing process‐based sediment transport models for gentle slopes in the northeastern hilly regions of China. [ABSTRACT FROM AUTHOR]

Tetracycline (TC), a widely used antibiotic, can easily enter aquatic ecosystems through soil erosion, livestock manures, and wastewater discharge, causes environmental and ecological health effects. AgCuFe2O4@Methylcellulose (MC)/Activated Carbon (AC) magnetic nanocomposite was synthesized accompanied by microwave-assisted co-precipitation procedure under green circumstances with high efficiency and subsequently utilized as a new heterogeneous magnetic nano-photocatalyst in the TC photodegradation from aqueous solutions. The structural characterization of AgCuFe2O4@MC/AC was performed by various analytical techniques. Afterwards, the key parameters of the photocatalytic TC degradation process, such as catalyst dose, TC concentration, pH, and process time, were investigated and optimized the results showed that the catalyst was synthesized on a nanometer scale (25 nm) with a quasi-spherical structure, with a high specific surface area, high magnetic strength (Ms = 19.27 emu g−1), and the preservation of the crystal structure. The removal efficiency of TC under optimal conditions including pH 7, initial TC concentration of 5 mg L−1, nano-photocatalyst dose of 0.5 g L−1, 90 min of irradiation time was reported to be 90.91% for synthetic sample and 87.17% for real wastewater sample. The removal effectiveness of total organic carbon was 85.2% under optimal conditions. The photocatalytic degradation kinetics of TC followed pseudo-first-order and Langmuir–Hinshelwood kinetic models, with values of KL–H = 0.633 L mg−1 and Kc = 0.126 mg L−1 min−1. After four cycles of recovery and regeneration, the synthesized catalyst demonstrated high chemical stability and was able to remove 62% of the pollutant. Finally, this study provides a viable approach for removing antibiotics using an AgCuFe2O4@MC/AC-based heterogeneous nanostructured photocatalyst. [ABSTRACT FROM AUTHOR]

Dams are vital for irrigation, power generation, and domestic water needs, but siltation poses a significant challenge, especially in areas prone to water erosion, potentially shortening a dam's lifespan. The Ahmed El Hansali Dam in Morocco faces heightened siltation due to its upstream region being susceptible to erosion-prone rocks and high runoff. This study estimates the siltation at the dam from its construction up to 2014 using bathymetric data and the Brown model, which is a widely-used empirical model that calculates reservoir trap efficiency. Additionally, the study evaluates the impact of Land Use and Land Cover (LULC) changes and projected future rainfall until around 2076 based on siltation rates. The results indicate that changes in LULC, particularly temporal variations in precipitation, have a significant impact on the siltation of the Ahmed El Hansali dam. Notably, rainfall is strongly correlated with the siltation rate, with an R2 of 0.92. The efficiency of sediment trapping (TE) is 97.64%, meaning that 97.64% of the sediment in the catchment area is trapped or deposited at the bottom of the dam. The estimated annual specific sediment yield is about 32,345.79 tons/km2/yr, and the sediment accumulation rate is approximately 4.75 Mm3/yr. The dam's half-life is estimated to be around 2076, but future precipitation projections may extend this timeframe due to the strong correlation between siltation and precipitation. Additionally, soil erosion driven by land management practices plays a crucial role in future siltation dynamics. Hence, this study offers a comprehensive assessment of the siltation dynamics at the Ahmed El Hansali dam, providing essential information on the long-term effects of erosion, land use changes, and climate projections. These findings may assist decision makers in managing dam reservoir sedimentation more effectively, ensuring the durability of the dam and extending the reservoir life. [ABSTRACT FROM AUTHOR]

Soil erosion is both the cause and effect of land degradation. Land use/land cover conversion that changes the inherent landscape structure of watersheds leads to soil loss increase. Pantabangan-Carranglan Watershed (PCW) as a major source of irrigation, electricity, biodiversity, livelihood, and other ecosystem services, thus, it is imperative to spatially and temporally estimate the soil erosion within its boundary to assist and guide decision-makers in planning conservation and management of the watershed. Using the Revised Universal Soil Loss Equation (RUSLE) model, remotely sensed data, soil analysis, and geographical information system, the soil erosion rate in PCW was estimated. Results showed that there is increasing soil erosion in PCW over time. In 2010 soil erosion rate was estimated to be 134 tons·ha-1·yr-1 which increased to 141 tons·ha-1·yr-1 and 154 tons·ha-1·yr-1 in 2015 and 2020, respectively. Considering the average soil erosion rate and land cover types in PCW, annual crop and open/barren land cover types have the highest average soil erosion rate through time with moderate and catastrophic erosion levels, respectively. [ABSTRACT FROM AUTHOR]

The Soil and Water Assessment Tool Plus (SWAT+) model depends on the Modified Universal Soil Loss Equation (MUSLE), which in turn depends on the peak runoff rate for the estimation of soil loss from a catchment. The SWAT+ model generates a random number for each day in the process of peak runoff rate estimation from the catchment. On the other hand, the model provides calibration parameters like the peak rate adjustment factor for sediment routing in the tributary channels and main channels. There is uncertainty that how likely the SWAT+ model estimates the actual peak runoff rates. An improved MUSLE does not depend on the peak runoff rate, and, therefore, it minimizes uncertainty related to the peak runoff rate when estimating soil loss from the catchment in the SWAT+ environment. On the other hand, the effect of the topographic factor of the MUSLE or improved MUSLE on soil erosion and sediment transport is not explicitly explained. Therefore, we modify the source code of the SWAT+ model for sediment yield estimation by replacing the improved MUSLE and the best-fitted equations of the topographic factor in the source code. The modified SWAT+ model showed better performance than the original SWAT+ model. [ABSTRACT FROM AUTHOR]

The present comprehensive review delves into the pivotal role of morphometric analysis in watershed management, particularly in prioritizing sub-watersheds (SW) and reservoir catchments. Herein, the authors highlight the critical areas of water spread, soil erosion patterns and aquifer recharge. The study emphasizes the significance of morphometric parameters for effective conservation measures. The review takes a multifaceted approach, analyzing various parameters, exploring mathematical expressions and discussing the tools for sub-watershed (SW) prioritization. The areal, relief and linear parameters play a crucial role in comprehending watershed drainage networks, which in turn impact soil erosion, runoff, flood etc. In view of utility of fundamental Horton's laws, the present study provides a detailed description of each parameter's classification where the range of values and the impact of digital elevation model (DEM) accuracy on morphometric analyses have been discussed. While acknowledging the laborious nature of traditional morphometric analysis, the review also advocates for modern data reduction methods such as principal component analysis (PCA). In the present work, we have described the gaps observed in the sequenced literature reports cited through the content. In addition, the assessing parameter correlations are also acknowledged for emphasizing the ongoing challenges. [ABSTRACT FROM AUTHOR]

The presence of livestock in riparian areas raises several questions about the conservation and sustainable use of water resources and biodiversity in Brazil. Although the Native Vegetation Protection Law (No. 12,651) focuses on riparian vegetation, protected as Permanent Preservation Areas (APPs), it does not exclude the presence of livestock in these fragile areas. Here, we provide an overview of APPs in Brazil and analyze the legal instruments that enable livestock in these areas, gathering the scientific evidence on associated environmental impacts. Currently, cattle in riparian areas represent a direct threat to biodiversity and ecosystem functioning and services, especially because these animals promote trampling, loss of vegetation, soil erosion, siltation, and pollution through urine and feces. To avoid cattle in APPs, legislation should be revised to implement more stringent restrictions; in parallel, alternatives for watering the animals must be sought, such as, for example, the installation of artificial ponds and drinking fountains. It would be appropriate to propose legislation or create incentives to fence livestock in pasture areas to preventing it from accessing APPs. Increasing cattle confinement is an alternative measure to traditional ranching in open pasture. Riparian zones represent a critical environment for biodiversity and society, so the presence of cattle and its associated negative impacts should be seriously considered by authorities. [ABSTRACT FROM AUTHOR]

Understanding long-term anthropogenic impact on the Earth's surface system is crucial for establishing reference conditions and potentially allowing future trajectories to be more rigorous and tightly constrained. In this study, the evolution of catchment erosion, chemical weathering and bottom-water hypoxia during the late Holocene are investigated using multi-proxy records from an accurately-dated sediment core from Lake Qilu in central Yunnan, southwest China. Through the comparison of our results with other paleoenvironmental records from the study region, we are able to see that the increase in anthropogenic impact on the catchment of Lake Qilu began in 780 CE, which is associated with the large scale expansion of agriculture in China. In the early stages of vegetation disturbance and agricultural land use, soil erosion and chemical weathering within in the catchment was significantly intensified, while the lake gradually changed to a state of anoxia until the period of accelerating eutrophication in 1945 CE. However, the extremely high rate of soil erosion and weak chemical weathering suggest the beginning of a new phase in terms of anthropogenic impact on the landscape. Furthermore, the late Holocene intensification of chemical weathering in monsoonal China can also be linked to increased anthropogenic activities rather than spatial differences in hydroclimate changes. This study highlights the fact that humans have been shaping the Earth's surface for millennia, which means that it is essential to place present environmental concerns into a long-term context. [ABSTRACT FROM AUTHOR]

With the advancement of urbanization, there has been a significant reduction in cultivated land, accompanied by soil erosion. Concurrently, the regularity of rainfall in recent years has been erratic, adversely impacting the grain economy and agricultural development in certain regions. Henan Province, spanning the basins of the Yangtze River, the Yellow River, the Huaihe River, and the Haihe River, possesses complex hydrological conditions and serves as a pivotal agricultural zone in China. Therefore, this paper utilizes daily rainfall data collected over 54 years (1969–2022) from 112 rain measuring stations in Henan Province to calculate the rainfall erosivity using the Zhang model and the erosivity model from the first national water survey. Meanwhile, spatial analysis was performed using the Kriging interpolation method in the ArcGIS Geostatistical Wizard, resulting in detailed spatial distribution maps of rainfall and rainfall erosivity. The study also employed Wavelet and Mann–Kendall tests to analyze the abrupt changes, trends and periodicity of rainfall and rainfall erosivity within the target region. The findings indicate that the average rainfall (1969–2022) in Henan province was 718.26 mm, while the average rainfall erosivity (R) was 3213.46 MJ mm/(hm2 h). R values are positively correlated with rainfall intensity and volume, displaying an annual upward trend. Spatially, R values increase gradually from northwest to southeast, closely aligning with topographical variations. Additionally, the analysis revealed a predominant periodic cycle of 54 years in the precipitation patterns. These results offer valuable insights for environmental and agricultural management in other regions of central China. [ABSTRACT FROM AUTHOR]

Scrub root systems play a crucial role in preventing soil erosion and nutrient loss. However, the effects of the root system configuration on soil nutrient dynamics and microbial changes at various evolutionary stages remain poorly understood. In this study, we investigated the relationship between soil physical and chemical properties and the diversity of bacteria and fungi throughout the evolutionary stages of the scrub root systems. This was achieved through a combination of whole-root excavation and root tracing techniques. The results indicated that root diameter was the main factor contributing to the continuous increase in carbon (C): phosphorus (P) and nitrogen (N): P ratios as the scrub sand pile developed. The soil organic carbon (SOC), total soil nitrogen (TN), and total soil phosphorus (TP) contents in the soil in the four evolutionary stages were the highest during the developmental stage, but the change in TP content was not statistically significant (P > 0.05). Partial least squares path modeling and redundancy analysis (RDA) indicated that root system stoichiometric C and N contents were positively correlated with microbial diversity (R² = 0.85). There was no correlation between the evolutionary stage and soil nutrient TN, whereas soil nutrient TN was negatively correlated with microbial diversity (R² = −0.92). These findings elucidate the relationship between the evolutionary stage of root chemical measurement characteristics, soil elements and microorganisms, and their subsequent effects on root elemental composition and microbial diversity. This study enhances the current understanding of plant–soil interactions in desert steppe ecosystems. [ABSTRACT FROM AUTHOR]

The current issue affecting land and water resources is soil erosion. Its numerous detrimental effects include deforestation, unfavorable farming methods, and decreased fertility, all of which impede socioeconomic growth. This research aimed to evaluate the effects of land use land cover (LULC) dynamics on soil erosion and its spatial distribution patterns over the Hare Watershed for the periods 2001–2021. Revised Universal Soil Loss Equation (RUSLE) model coupled with a geographic information system (GIS) was applied to estimate potential soil losses; this involved utilizing data on rainfall erosivity (R) using interpolating rainfall data, topography (LS) using digital elevation model (DEM), soil erodibility (K) using the William equation and digital soil map, conservation practices (P) using DEM and satellite images, and vegetation cover (C) using satellite images. To account for the change in LULC over the past 20 years, three separate maps of C‐factors were developed for the years 2001, 2011, and 2021. The remaining four factors were kept constant. Finally, after the successful running of the model, the estimated annual average soil loss rate (A) of the watershed is 211.38, 223.79, and 235.64 t·ha−1yr−1 for the years 2001, 2011, and 2021, respectively. This is a result of grazing areas and shrubland being lost for agricultural land. Moreover, in the past period, the watershed was found to show an increase in the yearly mean soil loss rate of 24.26 t·ha−1yr−1. Consequently, the northeastern, northwest, and southern regions of the watershed require the implementation of suitable land management. [ABSTRACT FROM AUTHOR]

Understanding the impact of climate and land use change on soil erosion is particularly important to the development and management of ecosystems. The purpose of this research was to differentiate the impacts of climate and land use alterations on soil erosion by using the InVEST model in the Anning River basin. The findings indicated a rise in average soil erosion from 42.78 t ha−1·a−1 to 49.84 t ha−1·a−1 over the decade from 2010 to 2020, with climate change accounting for 99.71% of the increase and land use change contributing 0.28%. The findings also indicated that the process of urbanization and the implementation of the Returning Grain to Forestry and Grass (RGFG) strategy were effective in decreasing soil erosion by 1.29 t ha−1·a−1 and 6.60 t ha−1·a−1, respectively. Four management measures were developed based on our results. The results of this study are not only of great significance for the environmental protection of a specific region, but also provide references for the mitigation of soil erosion in other regions of the world. [ABSTRACT FROM AUTHOR]

Urban rivers worldwide have been increasingly threatened by nitrate (NO3−) pollution. The Xianyang-Xi'an segment of the Weihe River, located in the loess plateau with serious soil erosion, has been highly urbanized and with intensive agricultural activities. Tracing the sources and transformations of NO3− is particularly challenging for this watershed which has multiple N sources and variable environmental factors. In this study, integrating antecedent studies with multiple stable isotopes and MixSIAR models, these river basins can be categorized into three classes: (1) urban areas, sewage, and manure were the predominant sources of NO3− in the Weihe River's mainstream, accounting for 73.4 ± 12.8%; (2) suburban areas, sewage and manure (Fenghe River, 58.0 ± 14.0%; Bahe River, 53.9 ± 15.0%) were recognized as the main sources of NO3−; (3) and the rural areas, ammonium nitrogen fertilizers were identified as the primary source of NO3− in the Heihe and Laohe Rivers. In addition, nitrification dominated the mainstream of the Weihe, Fenghe, and Bahe Rivers, while neither denitrification nor nitrification was evident in the Heihe and Laohe Rivers. In conclusion, this study is important for the improvement of surface water quality of rivers with different land use types and the development of targeted water environment management. [ABSTRACT FROM AUTHOR]

Rammed earth, a commonly used building material in ancient times, differs from natural sedimentary layers in that it is more compact. Buildings constructed from historical rammed earth sites frequently encounter the issue of rainwater erosion. Microbially induced calcium carbonate precipitation (MICP) is commonly applied to sand soil treatment, yet reports on its use for stabilizing rammed earth are scarce. This study focused on the rammed earth of the Shanhaiguan Great Wall and explored the efficacy of MICP in mitigating rain erosion through permeation tests, splash experiments, and scouring trials. The findings indicate that the forms of rain erosion damage under MICP treatment vary across different operational conditions. In laboratory experiments, as the concentration of the cementation solution increases, the amount of calcium carbonate crystals also increases. However, the permeability, splash resistance, and rain erosion resistance initially increase and then decrease. When the cementation solution concentration is 1.0 mol/L, the penetration rate is the highest, lasting 712.55 s. The splash pit rate is the lowest, at only 1.2 mm, and the soil erosion rate is the lowest, at only 4.13%. The rain erosion resistance in the field test exhibit the same trend, and the optimal concentration is 1.2 mol/L. The optimal concentration mechanism involves the aggregation of calcium carbonate crystals at suitable cementation solution concentrations, which begin to fill the soil particle pores, effectively resisting rainwater erosion. At lower concentrations of the cementation solution, calcium carbonate crystals are merely adsorbed by soil particles without blocking the pores. Due to the high compressibility of rammed earth, which results in lower porosity, a higher concentration of the cementation solution leads to rapid pore clogging by excessive calcium carbonate crystals, which accumulate on the surface to form a white crust layer. The MICP technique can effectively alleviate rainwater erosion in rammed earth, and the optimal concentration needs to be tailored to the porosity of the rammed earth. This mechanism was also validated in field scouring experiments on the Shanhaiguan Great Wall's rammed earth. [ABSTRACT FROM AUTHOR]

For maximization of soil and water quality benefits, the right agricultural conservation practices (CPs) should be practiced for the right place. The Agricultural Conservation Planning Framework (ACPF) is a tool that helps decision makers achieve precise conservation within a target watershed using rapid, low-cost Geographic Information System-based tools. ACPF takes the information on landscape characteristics and combines it with user input to identify locations susceptible to soil loss and water run-off and suggest potential CP locations. Suggested CPs may further be analyzed for urgency, installation cost, and effectiveness. In this study, ACPF was applied to analyze soil and water vulnerability within a small unglaciated sub-watershed in southwest Wisconsin and identify potential CP practices and recommended placement sites. To promote environmental sustainability in the agriculture sector, land managers are tasked with implementing CPs, but often lack adequate information on the most effective practice and placement strategy. Field-scale siting of CPs was achieved using high-resolution terrain derivatives and accurate simulation of the stream network. Slope disaggregation among soil loss vulnerability categories was also conducted. Greatest sources of vulnerability were associated with slope and erodibility factors, with average slope within cropped fields being 6% and erodibility being as high as 43%. Fields classified as critical for conservation had a mean slope of 7.4%. Suggested contour buffer strip (CBS) placement per field varied with slope, with steeper fields having denser placement. The results suggested that 3% of cropland could be removed from production if the recommended placement of CBS was implemented. A further 0.2% of the sub-watershed area would go to grassed waterways. The results support implementation of effective CPs based on local conditions and act as a tool to help reveal if existing practices in the sub-watershed are of a size and extent comparable to the predicted potential. [ABSTRACT FROM AUTHOR]

The black soil region experiences complex erosion due to natural processes and intense human activities, leading to soil degradation and adverse ecological and agricultural impacts. However, the complexities involved in quantifying regional erosion poses remarkable challenges in accurately assessing the current status of regional soil erosion for effective soil conservation. To solve this issue, we proposed a new method for monitoring soil erosion using Interferometric synthetic aperture radar (InSAR) technology and machine learning algorithms within the Google Earth Engine platform. The new method not only enables regional-scale monitoring, but also ensures high accuracy in measurement (millimeter-level). The erosion susceptibility of the study area (Yanshou County, Heilongjiang Province, Northeastern China) was also classified using random forest algorithms to refine the monitored and predicted soil erosion. The results indicate that the five-year (2016–2021) deformation in Yanshou County was −11.08 mm, with a significant mean cumulative deformation of −8.08 mm yr−1 occurring in 2017. The driving factor analysis shows that the region was subject to the compound effect of water and freeze–thaw erosion, closely related to crop phenological stages. The susceptibility analysis indicates that 73.3% of the region was susceptible to erosion, with a higher probability in river areas, at high altitudes, and on steep slopes. However, good vegetation cover can reduce the risk of soil erosion to some extent. This study offers a new perspective on monitoring regional soil erosion in the black soil region of China. The proposed method holds potential for future expansion to monitor soil erosion in a larger areas, thereby guiding the strategies development for protection of the agriculturally important black soil. [ABSTRACT FROM AUTHOR]

Forest carbon stock is an important indicator reflecting a forest ecosystem's structures and functions. Its spatial distribution is valuable for managing natural resources, protecting ecosystems and biodiversity, and further promoting sustainability, but accurately mapping the forest carbon stock distribution in a large area is a challenging task. This study selected Changting County, Fujian Province, as a case study to explore a method to map the forest carbon stock distribution using the integration of airborne Lidar, Sentinel-2, and ancillary data in 2022. The Bayesian hierarchical modeling approach was used to estimate the local forest carbon stock based on airborne Lidar data and field measurements, and then the random forest approach was used to develop a regional forest carbon stock estimation model based on the Sentinel-2 and ancillary data. The results indicated that the Lidar-based carbon stock distribution effectively provided sample plots with good spatial representativeness for modeling regional carbon stock with a coefficient of determination (R2) of 0.7 and root mean square error (RMSE) of 12.94 t/ha. The average carbon stocks were 48.55 t/ha, 55.51 t/ha, and 57.04 t/ha for Masson pine, Chinese fir, and broadleaf forests, respectively. The carbon stock in non-conservation regions was 15.2–16.1 t/ha higher than that in conservation regions. This study provides a promising method through the use of airborne Lidar data as a linkage between sample plots and Sentinel-2 data to map the regional carbon stock distribution in those subtropical regions where serious soil erosion has led to a relatively sparse forest canopy density. The results are valuable for local government to make scientific decisions for promoting ecosystem restoration due to water and soil erosion. [ABSTRACT FROM AUTHOR]

The Three Gorges Reservoir Area (TGRA) has often suffered the most serious soil erosion in recent years. Soil erosion control still remains on the purple soil, the main soil type for the sloping farmland in this area. Among them, enzyme- induced carbonate precipitation (EICP) can rely on the urease enzymes to catalyze urea. Specifically, the urea can be decomposed into ammonium and carbonate anions, and then precipitated the calcium carbonate (CaCO3) with the presence of carbonate anions and external calcium sources. EICP has been proven to efficiently strengthen the soil for less infiltration, in order to restore the rock and heritage. A promising approach can be regarded to effectively control soil erosion. However, the effect of EICP on the soil detachment capacity is still far from clear, especially for the response of soil detachment to the EICP concentration and maintenance time. Therefore, this study aims to clarify the effect of EICP solution concentration and maintenance duration on the soil detachment capacity of purple soil in the Three Gorges Reservoir Area. The purple soil in the TGRA was taken as the research material. The scouring experiments were conducted under five EICP solution concentrations (0 (for control check), 0.5, 1.0, 1.5, and 2.0 mol/L) at six maintenance durations (1, 7, 15, 30, 60, and 120 d), in order to estimate the soil detachment capacity. Also, the apparent cohesion and calcium carbonate content were measured at different experiment conditions. Moreover, the SEM was employed to reveal the micro-mechanism of erosion reduction by EICP. The results indicated that the soil detachment capacity of purple soil significantly decreased with the application of EICP solution. Compared with the CK, the soil detachment capacity decreased by 19.63%-86.92%, 38.79%-89.41%, 48.13%-89.91%, and 31.78%-84.49%, respectively, at the EICP solution concentration of 0.5, 1.0, 1.5 and 2.0 mol/L, with the most pronounced effect at the concentration of 1.5 mol/L. Additionally, the soil detachment capacity decreased rapidly, whereas, the subsequent slowly decreased as maintenance duration increased. Compared with the maintenance for 1 d, the decreases at 7, 15, 30, 60, and 120 d were 19.79%-84.08%, 33.81%-87.80%, 87.27%-94.21%, 91.41%-93.18%, and 91.18%-92.77%, respectively. Moreover, the reduction amplitude in the soil detachment capacity accounted for 85.79%-92.21% of the total reduction amplitude at the maintenance duration of 7 d under the application of the EICP solution. The apparent cohesion and calcium carbonate content of purple soil showed a trend of increase followed by a decrease with the increase of EICP solution concentration. Compared with the CK, the apparent cohesion increased by 43.70%-77.43%, 58.54%-101.21%, 77.06%-135.68%, and 64.08%-87.86%, respectively, at the EICP solution concentration of 0.5, 1.0, 1.5 and 2.0 mol/L, while the calcium carbonate content increased by 10.29-17.35 times, 11.12-23.00 times, 12.00-29.59 times and 10.88-24.35 times, respectively. Additionally, the apparent cohesion increased by 10.46%-36.38%, 21.98%-46.46%, 35.12%-55.41%, 45.15%-65.49%, and 48.61%-72.76%, respectively, at the maintenance for 7, 15, 30, 60 and 120 d, compared with the maintenance for 1 d. The content of calcium carbonate increased by 54.17%-133.48%, 60.94%-134.39%, 61.98%-134.84%, 61.46%-134.84%, and 62.50%-135.29%, respectively, at the maintenance for 7, 15, 30, 60 and 120 d under the application of EICP solution, compared with the stable content in the CK. The increase amplitude in the apparent cohesion and calcium carbonate content accounted for 37.59%-59.56% and 78.26%- 98.66% of the total increase amplitude, respectively, at the maintenance duration of 7 d. Additionally, the microscopic analysis exposed that the soil detachment capacity was reduced to aggregate the calcium carbonate in the soil surface under the application of EICP solution. Furthermore, the soil detachment capacity was better described by the apparent cohesion and calcium carbonate content with an exponential function. The findings can provide theoretical guidance to promote erosion control in the application of EICP on soil detachment of purple soil in the TGRA. [ABSTRACT FROM AUTHOR]

Soil and water conservation is one of the most important parts of the national ecological civilization. The spatial control area of soil and water conservation can be divided to effectively manage the soil and water loss regions. However, it is still lacking in the spatial delineation in the regional division of soil and water conservation. Only a few studies have been focused on the spatial control of soil and water conservation, according to the small watershed. This study aims to explore the spatial control zoning for soil and water conservation, and then implement the differentiated protection and management measures. The universal soil loss equation (USLE) model was used to calculate the potential and actual soil erosion. The main influencing factors of soil erosion were determined by random forests. A self-organizing feature map (SOFM) was used to determine the spatial control zone of soil and water conservation in the Dabie Mountain area on a small catchment scale. The results showed that: 1) The average potential and actual soil erosion were 84415.7 t/(km²·a) and 210.25 t/(km²·a), respectively. The actual soil erosion was distributed mainly in 0-300 t/(km²·a) at the small watershed scale. There was the basically same distribution of spatial patterns under the potential and actual soil erosion. The high-value area was distributed mainly in the central and eastern mountain areas at the high elevation. 2) Vegetation coverage and slope were the main influencing factors of potential and actual soil erosion at the small watershed scale, indicating a significantly positive correlation with the potential soil erosion (P<0.01). The high vegetation cover area was concentrated in the hinterland of Dabie Mountain. The high slope area was extended from the west to the east along the ridgeline of Dabie Mountain. 3) The SOFM results showed that the spatial control zone of soil and water conservation was divided into three areas: key prevention, general prevention, and the rest area at the small watershed scale. Among them, the key prevention area involved 710 small watersheds with an area of 1 5287.4 km². There were 890 small watersheds in the general prevention area, covering an area of 18 874.4 km². Two prevention areas accounted for 61.2% of the study area. There was an outstanding difference between actual and potential soil erosion and slope among regions. The classification index can serve as the spatial control of soil and water conservation. The finding can provide theoretical support and decision-making on the spatial control regionalization for soil and water conservation. [ABSTRACT FROM AUTHOR]

The drainage basins of Peninsular India are characterized by silicate-dominated lithologies, and influenced by Indian Summer Monsoon (ISM) precipitation. The Godavari River Basin (GRB), the largest river basin in Peninsular India situated within the ISM region, represents an ideal case for assessing weathering and climate interaction at different timescales. In this contribution, major and trace elemental geochemistry of a radiocarbon-dated sediment core (CY; 54.2 m long) from the Godavari delta region was investigated to reconstruct erosional changes in the Godavari basin in response to ISM variations during the Late Holocene. Comparison of geochemical data for the CY sediments and their possible sources confirm dominant sediment supply from the Deccan basalts and Archean Gneisses to the site. A distinct increase in Ti/Al, Ca/Al, and Cr/Al, along with a decrease in CIA* and LREE/HREE at 3.2 ka BP, point to relative increase in sediment supply from the Deccan Traps. Inverse model calculations of Al-normalized ratios of selected elements (Ti, Fe, V, Cr, Cu, Co) estimate that the core site on average receives ∼41 % sediments from the Deccan regions, which increased by ∼20% since last 3.2 ka BP. This accelerated erosion is attributed to the coupled effect of aridity-induced Deccan upland erosion with a relative decrease from the Archean rock source. This period of accelerated erosion coincides with the abandonment of Chalcolithic settlements. [ABSTRACT FROM AUTHOR]

Global warming poses an unprecedented threat to agroecosystems. Although temperature increases are more pronounced during winter than in other seasons, the impact of winter warming on crop biomass carbon has not been elucidated. Here we integrate global observational data with a decade-long field experiment to uncover a significant negative correlation between winter soil temperature and crop biomass carbon. For every degree Celsius increase in winter soil temperature, straw and grain biomass carbon decreased by 6.6 (± 1.7) g kg-1 and 10.2 (± 2.3) g kg-1, respectively. This decline is primarily attributed to the loss of soil organic matter and micronutrients induced by warming. Ignoring the adverse effects of winter warming on crop biomass carbon could result in an overestimation of total food production by 4% to 19% under future warming scenarios. Our research highlights the critical need to incorporate winter warming into agricultural productivity models for more effective climate adaptation strategies. This study reveals that winter soil warming causes significant crop biomass carbon loss due to soil organic matter degradation. Ignoring this effect could lead to a 4-19% overestimation of future food production. [ABSTRACT FROM AUTHOR]

A one-dimensional numerical overland flow model based on the cascade plane theory was developed to estimate rainfall-induced runoff and soil erosion on converging and diverging plane surfaces. The model includes three components: (i) soil infiltration using Horton's infiltration equation, (ii) overland flow using the kinematic wave approximation of the one-dimensional Saint-Venant shallow water equations for a cascade of planes, and (iii) soil erosion based on the sediment transport continuity equation. The model's performance was evaluated by comparing numerical results with laboratory data from experiments using a rainfall simulator and a soil flume. Four independent experiments were conducted on converging and diverging surfaces under varying slope and rainfall conditions. Overall, the numerically simulated hydrographs and sediment graphs closely matched the laboratory results, showing the efficiency of the model for the tested controlled laboratory conditions. The model was then used to numerically explore the impact of different plane soil surface geometries on runoff and soil loss. Seven geometries were studied: one rectangular, three diverging, and three converging. A constant soil surface area, the rainfall intensity, and the slope gradient were maintained in all simulations. Results showed that increasing convergence angles led to a higher peak and total soil loss, while decreasing divergence angles reduced them. [ABSTRACT FROM AUTHOR]

The terrain in the loess hilly area of western Henan is fragmented, with steep slopes and weak soil erosion resistance. The substantial soil erosion in this region results in plenty of problems, including decreased soil productivity and ecological degradation. These problems significantly hinder the social and economic development in the region. Soil conservation planning and ecological development require accurate soil erosion surveys. However, the studies of spatio-temporal patterns, evolution, and the driving force of soil erosion in this region are insufficient. Therefore, based on a multi-stage, unequal probability, systematic area sampling method and field investigation, the soil erosion of the loess hilly area of western Henan was quantitatively evaluated by the Chinese Soil Loss Equation (CSLE) in 2022. The impact forces of soil erosion were analyzed by means of a geographic detector and multiple linear regression analysis, and the key driving factors of the spatio-temporal evolution of soil erosion in this region were revealed. The results were as follows. (1) The average soil erosion rate of the loess hilly area in western Henan in 2022 was 5.94 t⋅ha−1⋅a−1, with a percentage of soil erosion area of 29.10%. (2) High soil erosion rates mainly appeared in the west of Shangjie, Xingyang, and Jiyuan, which are related to the development of production and construction projects in these areas. The areas with a high percentage of soil erosion area were in the north (Xinan and Yima), west (Lushi), and southeast (Songxian and Ruyang) of the study area. Moreover, areas with the most erosion were found in forest land, cultivated land, and areas with a slope above 25°. (3) At the landscape level, the number and density of patches of all land types, except orchard land, increased significantly, and the boundary perimeter, landscape pattern segmentation, and degree of fragmentation increased. (4) The geographical detector and multiple linear regression analysis indicated that the driving forces of soil erosion are mainly topographic and climatic (slope length, elevation, precipitation, and temperature). Soil erosion was significantly influenced by the density of landscape patches. These maps and factors influencing soil erosion can serve as valuable sources of information for regional soil conservation plans and ecological environment improvements. [ABSTRACT FROM AUTHOR]