Soil Erosion Control Research Articles

Studying Methods of No-till in the Garabagh Plain

The research results are presented and a comparative assessment of the methods of no-till soil cultivation in the Karabakh Plain is given. The advantages and disadvantages of moldboard tillage, direct sowing and the effect of hoeing a plowed or milled field on the loss of NPK per 1 ha as a result of erosion were studied. The author concludes that direct seeding is one way to reduce erosion. This must be used along with other soil erosion control methods.

Impact of participation in collective action on farmers’ decisions and waiting time to adopt soil and water conservation measures

PurposeThis study aims to analyze the influence of farmers’ degree of participation in collective action on their adoption decisions and waiting time regarding soil and water conservation (SWC) measures.Design/methodology/approachThe Probit model and Generalized Propensity Score Match method are used to assess the effect of the degree of participation in collective action on farmers’ adoption decisions and waiting time for implementing SWC measures.FindingsThe findings reveal that farmers’ engagement in collective action positively influences the decision-making process regarding terrace construction, water-saving irrigation and afforestation measures. However, it does not significantly impact the decision-making process for plastic film and ridge-furrow tillage practices. Notably, collective action has the strongest influence on farmers’ adoption decisions regarding water-saving irrigation technology, with a relatively smaller influence on the adoption of afforestation and terrace measures. Moreover, the results suggest that participating in collective action effectively reduces the waiting time for terrace construction and expedites the adoption of afforestation and water-saving irrigation technology. Specifically, collective action has a significantly negative effect on the waiting time for terrace construction, followed by water-saving irrigation technology and afforestation measures.Practical implicationsThe results of this study underscore the significance of fostering mutual assistance and cooperation mechanisms among farmers, as they can pave the way for raising funds and labor, cultivating elite farmers, attracting skilled labor to rural areas, enhancing the adoption rate and expediting the implementation of terraces, water-saving irrigation technology and afforestation measures.Originality/valueDrawing on an evaluation of farmers’ degree of participation in collective action, this paper investigates the effect of participation on their SWC adoption decisions and waiting times, thereby offering theoretical and practical insights into soil erosion control in the Loess Plateau.

Calcium alginate−biochar composite promotes nutrient retention, enzyme activity, and plant growth in lime soil

Soil nutrients loss in karst area is an urgent eco-environmental problem. To control soil erosion and improve soil quality, calcium alginate−rice straw biochar composite (CA−MRB300) was prepared by embedding method. The retention mechanisms of soil nutrients onto CA−MRB300 were explored through batch adsorption experiments of soil nutrients, soil column leaching experiments combined with the analysis of physicochemical properties and soil enzyme activity. The effects of CA−MRB300 and its co-application with fertilizer on plant growth were investigated by a pot experiment. The results suggested that CA−MRB300 effectively retained PO43− and NO3− in lime soil mainly through surface precipitation and physical adsorption. The addition of CA−MRB300 increased the activities of alkaline phosphatase, urease, and sucrase in lime soil. Increased activity of urease accelerated the hydrolysis of urea to NH4+ in lime soil. Compared to a low proportion, a high proportion of CA−MRB30 was more likely to lead to the loss of K+. Moreover, the application of CA−MRB300 alone was more beneficial to the growth of soybean than the co−application of CA−MRB300 with fertilizer. This study indicates that CA−MRB300 has a great potential for application in retaining nutrients and promoting crop growth in lime soil.

Quantifying soil erosion and soil organic carbon conservation services in indian forests: A RUSLE-SDR and GIS-based assessment

Indian forests, having sixteen types of vegetation, provide various ecosystem services. Forests reduce water erosion of soil, reduce floods and conserve low river flow during dry seasons. Present study estimated annual sedimentation, texture, soil organic carbon control service of forests of India using the Revised Universal Soil Loss Equation (RUSLE) and Sediment Delivery Ratio (SDR) approach through GIS technique along with identifying important drivers responsible for erosion in forests. The soil erosion control service was based on five factors viz., rainfall erosivity, soil erodibility, slope, crop management, conservation practice factor and SDR across the various forest dominated river basins. Geo-detector modelling was performed to evaluate environmental drivers responsible for soil erosion. Valuation of soil control service of the India’s forests was estimated based on damage and replacement cost method. Annual soil loss rate was maximum in Tropical Thorn Forest and in Ganga River basin. Maximum sediment control and SOC conservation against the soil erosion control service by India’ forests were due to Tropical Dry Deciduous Forest with a total annual sedimentation control and SOC conservation of 33,056,560 tonnes and 3,31,115.06 tonnes, respectively. The conservative estimate of the economic value of soil conservation service by the forests of India was US$ 535.6 M with an average of 4.40 US$ ha−1 and a maximum share of value for Tropical Dry Deciduous Forest i.e. 294.18 million US$ and average maximum value for Littoral and Swamp Forest (28.91 US$ ha−1). The soil erosion in Tropical and Sub-tropical Forest was influenced by the interactive effects between NDVI and Bulk Density. In contrast, soil erosion in the temperate and alpine area was influenced by anthropogenic activity in combination with climatic factors. Present study accounts the role of India’s forests for the soil conservation service and may provide inputs to implement forest and reservoir management strategies besides providing information for Integrated Watershed management and Catchment Treatment Plans.

Prioritization of soil erosion-prone sub-watersheds using geomorphometric and statistical-based weighted sum priority approach in the middle Omo-Gibe River basin, Southern Ethiopia

ABSTRACT Soil erosion, a major factor contributing to land degradation, poses significant environmental challenges across sub-Saharan Africa, including Ethiopia. This study identifies erosion-prone sub-watersheds in southern Ethiopia's middle Omo-Gibe River basin using digital elevation model data, analyzed using a geomorphometric and statistically weighted sum priority approach in a Geographic Information System environment. Additionally, hypsometric analysis, lithology, land use/cover analysis, and field observations were integrated to enhance methodological reliability in assessing soil erosion patterns and subsequent land degradation in the basin. Results highlight sub-watersheds with varying degrees of erosion sensitivity, emphasizing morphometric parameters and landscape characteristics. Furthermore, hypsometric analysis confirms a moderate to high susceptibility of sub-watersheds to soil erosion. Moreover, half of the river basin consists of shrubland, encompassing scrubs, range lands, and small wooded areas. These are less efficient in mitigating erosion compared to forests, especially in the face of significant summer rainfall and ensuing runoff. Statistical prioritization identified 19 sub-watersheds, covering 43% of the basin's total area, as highly prone to soil erosion and land degradation. The study's findings are valuable for Ethiopian watershed management decision-makers, enabling informed resource allocation and targeted interventions to control soil erosion and protect water resources by utilizing the outputs of this study.

Spatial-temporal variation and correlation between vegetation coverage and soil conservation of Ten Kongdui watershed in the Yellow River basin

The Ten Kongdui watershed is an essential part of the upper Yellow River baisn of China. The ecosystem in this region has low stability and hazards of sandstorm and soil erosion are serious. By studying the spatio-temporal changes and spatial correlation between vegetation cover and soil conservation, the inhibition effect of vegetation on soil erosion in time and space can be clarified, and the driving factors of soil erosion in a certain area can be further explained. The research results provide data support for artificial vegetation construction and soil erosion control in the Yellow River basin in the future. In this study, the invest model was used to calculate the soil retention of the watershed, and then the spatial autocorrelation analysis was used to analyze the vegetation coverage and soil retention in space. The relationship between changes of the vegetation coverage and soil conservation during 2000–2020 in the Ten Kongdui watershed is analyzed in this paper. The research shows that: (1) During the research period, the vegetation coverage maintained an increasing trend in Ten Kongdui watershed; (2) From 2000 to 2020, with the increased vegetation coverage, soil retention increased, indicating that increasing vegetation coverage can effectively prevent soil erosion; and (3) Vegetation coverage and soil conservation presented a local spatial auto-correlation, Moran’s I index was less than 0, but the years from 2000 to 2020 witnessed gradual growth of the correlation coefficient. There are significant differences in spatial distribution. ‘High-high’ and ‘low-low’ are sporadically distributed in the sandstorm area on the middle reaches of Kubuqi and sporadically in the hilly and gully areas on the upper reaches. Moreover, ‘high-low’ and ‘low-high’ correlation coefficients were distributed in gully areas on the upper reaches and alluvial plains on the lower reaches. The alluvial plains on the lower reaches are mainly farmland ecosystems, with a high NDVI in the growing season but poor soil erosion resistance and weak soil conservation ability. The results emphasized the importance of vegetation coverage change in space for soil conservation of different type of underlying surfaces. The vegetation coverage change effects of soil conservation in plain terrain will be muted. This work provided a certain theory and criterion for us to further research the predictive model of soil erosion .

A GIS‐based approach to site vegetated buffer strips for erosion control within an agricultural catchment in southern England

AbstractAgricultural soil erosion is largely attributed to arable intensification and increased mechanization. Runoff from arable land and intensively managed grassland transports sediment and contaminants across the landscape and into watercourses, causing crop loss, land degradation, and water quality issues. One low‐cost and low‐maintenance nature‐based mitigation approach is the implementation of vegetated buffer strips (VBS): grassland sited along field margins to trap sediment and contaminants, reducing transportation and diffuse pollution rates. GIS modelling using remotely sensed landscape indices and land parcel data can provide an efficient means of identifying priority areas for intervention at sub‐catchment or farm system scales. We develop and test a scalable runoff risk model in the lower Rother catchment, West Sussex. The model uses the Normalized Difference Vegetation Index (NDVI) applied to satellite images as an erodibility proxy and identifies locations along pathways that are conceivably at greatest risk of sediment accumulation and transfer, guided by field observations. We assess current and historical field boundaries near high‐risk locations, evaluating the potential capacity of their margins to contribute to runoff risk reduction using an innovative ranking system. Recommendations are made for VBS implementation and the value of historical field boundary and margin restoration is discussed. Our method offers a rapid approach with minimal data requirements to identify high‐risk sediment runoff locations and priority sites for intervention. The tool has the potential to guide decision‐makers responsible for targeting and implementing soil erosion and runoff control measures such as VBS, while also maximizing agri‐environmental and cultural benefits.

Rainfall intensity profile induced changes in surface‒subsurface flow and soil loss as influenced by surface cover type: A long-term in situ field study

Due to global warming, changes in the rainfall intensity profile (i.e., the temporal intensity distribution within a rainfall event) increase the difficulty of accurate erosion prediction and control. Surface cover has been widely used as a critical measure to control soil erosion worldwide. However, the effects of the rainfall intensity profile (RIP) on soil erosion under different surface covers are not fully understood. In this study, long-term in situ field observations of the rain hyetograph, surface runoff coefficient (SRC), subsurface flow rate (SFR), and soil loss rate (SLR) from bare land, litter cover and grass cover were conducted over 11 consecutive years in the red soil hilly region of southern China. According to the occurrence time of the most intense rainfall, 226 erosive events were classified into four RIP patterns: advanced, intermediate, delayed, and uniform patterns. The results indicated that the advanced pattern with short duration–high intensity and the delayed pattern with long duration–high depth contributed to 73.45% of the total erosive events. For bare land, advanced events were the dominant pattern producing surface runoff and soil erosion, accounting for 57.24% and 75.17%, respectively, of the total surface runoff and erosion. The average SRC and SLR from the advanced pattern were 1.29–2.42 times and 2.52–39.78 times greater than those from the other patterns, respectively. The delayed pattern contributed to subsurface flow, and the average SFR was 1.27–2.17 times greater than that of the other patterns. Furthermore, surface cover significantly reduced surface runoff and erosion and increased subsurface flow, especially under the advanced pattern. Both surface cover measures were equally effective in controlling surface runoff and erosion, but the increase in subsurface flow caused by litter cover was 1.38–2.67 times greater than that caused by grass cover. Advanced pattern events increase the erosion risk on red soil slopes, and surface cover effectively weakens the effect of variation in the RIP pattern on soil erosion. Moreover, surface cover significantly alters the surface‒subsurface flow distribution pattern for all the RIP patterns. This study highlights the crucial importance of rain intensity profiles on water erosion and provides a basis for optimizing measures to effectively control soil and water loss under climate change.

Climate change impairs the effects of vegetation improvement on soil erosion control in the Qinghai-Tibetan Plateau

Water erosion is a wide ecosystem degradation threat for the Qinghai-Tibetan Plateau (QTP) region and surrounding areas. Climate wetting and vegetation greening in the QTP could have complex impacts on water erosion. However, there is limited information about the erosion dynamics under climate change and the effects of vegetation improvement on erosion control in this alpine region. By calibrating the Revised Universal Soil Loss Equation (RUSLE) model, we estimated water erosion in the QTP and simulated future changes using different Shared Socioeconomic Pathway-Representative Concentration Pathway (SSP) scenarios. We showed intensified erosion and that the benefits of vegetation improvement to erosion control was impaired under climate change. Under the SSP585 scenario, annual water erosion in the QTP was predicted to increase by 0.35 t∙ha−1∙yr−1 and be dominated by an accelerative rise of rainfall erosivity (R factor of RUSLE). Compared with historical observations, the C factor of RUSLE under the SSP585 scenario was believed to reduce by 4.35 % on average during the 2081–2100 period, but predicted soil loss will increase by more than 90 %. Although more considerable vegetation improvement could occur under high climate forcing, there may also be more intensified rainfall erosivity and water erosion across the QTP than those under SSP126 and SSP245 scenarios. Our results suggest that mitigating climate change rather than vegetation improvement is essential to address climate-dominated ecosystem degradation threats such as water erosion in the QTP.

Local Perceptions of Forest-Based Ecosystem Services in Benin, West Africa

Ecosystem services are closely linked to the daily lives of local communities, particularly those living near forests. The study of the local perceptions of these services is relevant because they vary depending on the community, the study period, and the environment. So beyond the inventorying of ecosystem services, understanding the perceptions of local communities regarding these services remains a necessity. Our study aims to analyze how local communities perceive the ecosystem services provided by forests and the factors that determine these perceptions. We collected data from 232 heads of households across 23 villages bordering the forest and analyzed them using descriptive statistics and ordered Probit analysis. The results showed that provisioning services (such as plant-derived medicines, rafters and planks, livestock feed, crops, and firewood) were the most important, followed by regulating and supporting services (including soil formation, erosion control, and climate regulation) are the most important. Finally, cultural services (encompassing cultural practices, heritage, and spirituality) were perceived as important. However, communities did not perceive the value of ecotourism. Factors influencing these perceptions included gender (male), age (young individuals), occupation in farming, household size, level of education, Bariba ethnicity and income. To ensure the sustainable utilization of forest resources in the region, it is necessary to encourage young people to adopt environmentally friendly agricultural practices, to use improved stoves that require less wood and promote cultural services to diversify their sources of income.

Analysing the influence of surface greening on soil conservation in China using satellite remote sensing

Global surface greening is very important to slow down regional warming, promote ecological balance and sustainable development, and China has made a significant contribution to this in the past 30 years, and effectively alleviated environmental problems such as land degradation, water shortage and air pollution by rapidly increasing vegetation coverage. Previous studies have shown that vegetation plays a positive role in alleviating soil erosion, but there is no quantitative description of runoff erosion and sediment transport under vegetation evolution with long time series and high resolution in China area. In this study, we use the RUSLE model and multi-source satellite remote sensing data to simulate overland soil erosion in China from 1990 to 2020 and analyze both the temporal and spatial variation of vegetation avoided erosion (VAE) and its correlation with multiple driving factors, such as Gross Primary Production (GPP). The results show that: 1)The distribution has increased by 12.89 % from 1990 to 2020, which is significant, and indicates that greening of the surface has significantly prevented soil and water loss;2)The spatial correlation strength of VAE-GPP in China is roughly in line with the division of the Hu Huanyong line (Hu-line), which is the result of the combined effect of vegetation distribution and human activities;3)The efficiency of VAE was significantly improved, especially the forest, accounting for about 76.50 % of the total, which was twice the sum of the other types. The research conclusion is of great significance to soil erosion prevention and control, soil ecological improvement, vegetation dynamic planning and regional sustainable development.

Soil properties of thickets and adjacent land use types in coastal savanna landscape of Ghana

Thicket vegetation may be of great importance in soil carbon (C) storage and in provision of other ecosystem services such as soil erosion control and biodiversity conservation. However, it is less studied in tropical ecosystems due to limited understanding of its ecological importance. This study reports soil C pools and nutrient concentrations [nitrogen (N), available phosphorus (P), exchangeable calcium (Ca), magnesium (Mg) and potassium (K)] of unique thicket formations on Vertisol in comparison with adjacent land use types viz. rangeland, dry forest, and farmland at Kpong in the coastal Accra plains of Ghana. We also examined soil particle and nutrient distributions of termitarium associated with the thicket clumps on the Vertisols. Soils were sampled from each land use at 0–30 cm depth in addition to deep coring up to 100 cm. In the rangeland, forest and farmland, we demarcated 1600 m2 area each and established 4 subplots measuring 20 × 20 m (400 m2) and selected for the thicket vegetation, 4 thicket clumps each of approximately 400 m2 for soil sampling. The thicket clumps had greater soil total N, available P, exchangeable Ca and Mg concentrations than the rangeland and farmland but the levels in the thicket were similar (p > 0.05) to that of the adjacent dry forest. Soil C stock varied from 59 Mg ha−1 in the rangeland to 111 Mg ha−1 in the thicket clumps. The C stored in the silt + clay (S + C) fraction did not differ significantly (p > 0.05) in both the thicket and the dry forest, indicating similar C sequestration abilities. The S + C fraction contributed 89.6, 82.8, 81.3, and 73.7% to total soil organic C content in the rangeland, farmland, dry forest, and thickets, respectively. Soils of the termite mounds in the thickets were more clayey (ca. 38–41% clay) than the surrounding thicket soils (ca. 32% clay). We conclude that Vertisols in thicket areas store soil C and nutrients comparably as tropical dry forest, underscoring their ecological importance and the need for their conservation to enhance soil quality in the Anthropocene.

Numerical simulation of shelter effect assessment for single-row windbreaks on the periphery of oasis farmland

Dust storms, resulting from aeolian erosion, pose significant environmental hazards, while farmland is one of the main sources of dust storm release. An effective strategy to mitigate surface wind speed and curb dust emissions involves the establishment of windbreaks on the periphery of oasis farmland. This study conducts a series of numerical simulations using computational fluid dynamics (CFD) to explore the airflow fields around windbreaks with diverse systematic structural parameters, encompassing porosity, planting spacing, and fence effects. The main findings are as follows: (1) When the vegetation porosity is consistent (e.g., porosity α = 0.7, 0.8, and 0.9), exact geometry results can effectively reflect the distribution of wall shear stress, while the porous medium model overlooks these details. (2) The “Venturi effect” contributes to the acceleration of surface erosion and improper planting spacing results in an elevation of near-surface velocity. Planting spacing of 0.5 m demonstrates superior wind speed reduction performance, mitigating aeolian erosion and accumulation. (3) When the fence is positioned at l = 5h (h represents the height of the windbreaks), the flow field around the windbreaks is minimally influenced. The optimal placement distance for fences should be close to the windbreaks, featuring minimal porosity (l = 0 h, α = 0.1), extending the shelter distance from 3 to 4 h to 5–6 h. The research results can provide a theoretical basis for optimizing the plant configuration of biological desertification control and soil erosion control measures.

Soil Erosion Assessment and Early Warning Model Based on Big Data and Artificial Intelligence

Soil erosion can lead to the pollution of water bodies, further deterioration of the ecological environment, and pose a serious threat to humans and the biodiversity of the earth. In order to cope with this global challenge, it is particularly important to develop soil erosion assessment and early warning systems. With the support of soil erosion model and geographic information system, a new soil erosion assessment and early warning system based on the soil and water environment of Jilin Province was developed in this paper. The system can analyze rainfall data, satellite data and geographic information data more accurately, and then find out the key factors causing soil erosion. The study found that the slope had the greatest correlation with soil erosion, with a correlation of 1.12. The second is the soil type and vegetation type, and in the steep slope of > 25°, soil erosion is severe, and the land ecological condition is very poor. These research results not only have important reference value for the land spatial planning of Jilin Province, but also provide valuable experience and reference for the soil erosion control work in other areas. Through scientific planning and early warning system, it is expected to protect valuable land resources, maintain the ecological balance of the earth, and contribute to the sustainable development of mankind.

An Overview of the Importance of DEM Resolution in Soil Erosion Assessment

Soil erosion is a geomorphic process that can cause hazards and socioeconomic losses. These processes occur through subsurface and overland flows. We conducted a literature review on the importance of digital elevation model (DEM) resolution in soil erosion assessment. This review article presents the state of the art regarding the importance of the resolution of DEM in soil erosion assessment. It explains why DEM resolution is important for understanding how erosion is assessed. Further research is needed, however, to better explore the connectivity and morphology of soil erosion, including its subsurface watershed and behavior, as well as several challenges faced in using DEMs for soil erosion analysis. Understanding quantitative variables that initiate soil erosion and considering multihazard assessments can aid in developing techniques and assisting decision makers in designing accurate systems. Exploring soil erosion also needs improved high-resolution tools (e.g., unmanned aerial vehicles) that enable more reliable predictions of soil erosion and the detection of erosion-affected regions. Addressing these knowledge gaps will enhance our understanding of subsurface and surface erosion, contribute to a better understanding of landscape evolution, and further improve the development of effective strategies and techniques for soil erosion control. The research findings are highly transferable in diverse geographical contexts worldwide.

Analyzing spatio-temporal changes and trade-offs/synergies of gross ecosystem product based on water-energy-food nexus.

The value of the ecosystem's ultimate goods and services for human welfare and long-term economic and social development is known as the gross ecosystem product (GEP). For the study of GEP accounting, the suggested water-energy-food (WEF) nexus offers a fresh viewpoint. This work aims to build a GEP accounting index system based on WEF, investigate its spatio-temporal evolution characteristics, and assess trade-offs and synergies between and within the water, energy, and food subsystems. Using the Three Gorges Reservoir area (TGRA) as an illustration, the findings revealed that, firstly, the comprehensive benefit of GEP based on WEF showed an upward trend in TGRA. Still, it was worth noting that the total production of the food ecosystem decreased. Secondly, the GEP based on WEF in five periods showed a spatial pattern of "high east and west, low middle." Thirdly, the Pearson correlation coefficient indicated that the GEP trade-off relationships based on WEF were dominant in TGRA, with the strongest trade-offs between AQV, SCV, APV, and LEV. In addition, in bivariate local spatial autocorrelation, the value of the six ecosystem service function relationships was dominated by the trade-off relationship, and the distribution of trade-offs and synergies showed significant heterogeneity at the county scale in the TGRA. Finally, hot spot analysis showed that the hot spots of the gross water and energy ecosystem products were scattered in the tail area of the study area. In contrast, the hot spots of the gross food ecosystem product were concentrated in the belly region. The findings of this study provided a basis for the scientific formulation of territorial spatial pattern optimization for water, energy, and agricultural resources in the TGRA and can more accurately reflect the status of the ecological environment and changes of WEF over time. Moreover, this paper also gives full play to the growth advantages of shipping and aquatic products, implements effective soil erosion prevention and control measures, and establishes water-saving mechanisms and other measures in terms of water resources. Subregional plans for industrial structure and strengthening of waste gas and wastewater treatment facilities regarding energy resources are developed. Implement the cultivated land protection system and promote the superiority of crop varieties and other measures in terms of food resources.

Evaluating the Accuracy of Contour Ridgeline Positioning for Soil Conservation in the Northeast Black Soil Region of China

The Northeast black soil region is China’s vital commercial grain base. However, severe soil erosion on slope farmland poses a significant threat to this region’s sustainable agricultural productivity. The transition from traditional downslope ridging to contour ridging (briefly referred to as “contour ridging”) is one of the primary sustainable measures for preventing soil erosion on slope farmland. By integrating high-precision Digital Elevation Models (DEMs) and design standards, ArcMap can plan the orientation and position of contour ridgelines and estimate the reduction in soil erosion on slope farmland after implementing contour ridging. Therefore, the degree of discrepancy between the designed and implemented positions of the contour ridgelines directly affects the effectiveness of contour ridging and the precision in evaluating its impacts and benefits. This study aims to assess the position accuracy of contour ridgelines designed by ArcMap 10.5 (here after ArcMap) using high-precision DEMs obtained from unmanned aerial vehicles (UAV). For this purpose, three fields where contour ridging had already been implemented were selected in the Sanjiang Plain of Heilongjiang Province, China. CORS RTK was used to measure the XYZ coordinates of verification points along implemented ridges precisely. Those measured coordinates were compared with the designed ridgeline positions to analyze the positional discrepancies between the designed and implemented ridgelines. The results indicated the following: (1) The average slope gradient along contour ridgelines measured in the field (0.5~0.6°) was relatively close to that along the ridgelines designed using ArcMap (0.6°), and the elevation changes along most of the contour ridgelines showed a pattern of being higher in the middle and lower on both sides. (2) The positional offset between most of the measured and designed ridgelines was less than the width of a single ridge (1.3 m), and the median offset was one-third of the width of a single ridge. (3) The positional offset caused by the movement of ridging machinery could be larger than the offset resulting from the baseline setup, and verification points with larger positional offsets were often located at the edges of the plots as well as turns of the ridgelines. Therefore, during the designing ridgelines process, the turns should be made as smooth as possible. During ridging, reducing the speed at these turns to minimize errors and maintain the accuracy of the ridgeline was recommended. The findings of this study can provide a scientific basis to improve contour ridging design and effect prediction in slope farmland to control soil erosion and enhance agricultural sustainability.

An assessment of the shade and ground cover influence on the mitigation of water-driven soil erosion in a coffee agroforestry system

Coffee cultivation under agroforestry systems is one of the main agricultural activities in Central America, but climate change is putting its sustainability at risk. Rainfall erosivity has worsened, thus driving soil losses. Although the vegetal covers in coffee agroforestry systems play a crucial role in controlling erosion, the specific influence of each cover layer remains unclear. In this study, we assessed the influence of the canopy (tree and banana cover and coffee cover) and ground cover (weed and litter) on water driven soil erosion, to determine which type of cover has the most influence on soil erosion control. The study site is situated in the core and buffer zones of the Macizo de Peñas Blancas National Park (Nicaragua), where seventeen coffee sampling plots with an agroforestry system composed of an Inga spp and Musa spp canopy cover were analysed. The results showed that the 19.2 ± 3.4% of the soil surface was affected by erosion and it was mainly related to the litter ground cover (r = –0.95, P < 0.001). Also, this cover presented the best partial correlation (ryl.tcw = –0.93, P < 0.001) when the effects of the other vegetal covers were eliminated. Specifically, the litter cover accounted for 90% of the erosion variability, while the impact of the other types of cover was negligible, accounting for just 1% of the erosion. We conclude that litter layer is more important than canopy cover for effective erosion control, and the main function of shade trees is as a source of litter biomass.

An integrated modeling approach for estimating monthly global rainfall erosivity

Modeling monthly rainfall erosivity is vital to the optimization of measures to control soil erosion. Rain gauge data combined with satellite observations can aid in enhancing rainfall erosivity estimations. Here, we presented a framework which utilized Geographically Weighted Regression approach to model global monthly rainfall erosivity. The framework integrates long-term (2001–2020) mean annual rainfall erosivity estimates from IMERG (Global Precipitation Measurement (GPM) mission’s Integrated Multi-satellitE Retrievals for GPM) with station data from GloREDa (Global Rainfall Erosivity Database, n = 3,286 stations). The merged mean annual rainfall erosivity was disaggregated into mean monthly values based on monthly rainfall erosivity fractions derived from the original IMERG data. Global mean monthly rainfall erosivity was distinctly seasonal; erosivity peaked at ~ 200 MJ mm ha−1 h−1 month−1 in June–August over the Northern Hemisphere and ~ 700 MJ mm ha−1 h−1 month−1 in December–February over the Southern Hemisphere, contributing to over 60% of the annual rainfall erosivity over large areas in each hemisphere. Rainfall erosivity was ~ 4 times higher during the most erosive months than the least erosive months (December–February and June–August in the Northern and Southern Hemisphere, respectively). The latitudinal distributions of monthly and seasonal rainfall erosivity were highly heterogeneous, with the tropics showing the greatest erosivity. The intra-annual variability of monthly rainfall erosivity was particularly high within 10–30° latitude in both hemispheres. The monthly rainfall erosivity maps can be used for improving spatiotemporal modeling of soil erosion and planning of soil conservation measures.

Effects of soil erosion–deposition on corn yields in the Chinese Mollisol region

Soil erosion is a major challenge for crop production maintenance and improvement in agricultural regions worldwide. However, quantifying the impacts of soil erosion rate on crop yield has not been carried out often, and there are few reports on impacts of soil deposition crop yields, especially in the Chinese Mollisol Region. Thus, this study quantified soil erosion–deposition rates (SEDRs) at three agricultural catchments in the Chinese Mollisol region using the 137Cs technique and assessed soil erosion–deposition impacts on corn (Zea mays L.) yield. The results showed that SEDRs varied from −5471.7 (deposition) to 9956.0 (erosion) t km−2 yr−1. The distributions of both soil erosion and deposition in the three catchments were in coexistence, but soil erosion was dominant. In addition, above 2500 t km−2 yr−1 of soil erosion rates (larger than slight erosion rates) in the three catchments accounted for 41.0 %, indicating that soil erosion was severe. Moreover, corn yields in the three catchments ranged from 1.9 to 14.6 t ha−1. Compared with deposited sites, corn yields in eroded sites were 19.2 %–40.6 % lower. Furthermore, when soil erosion rates were moderate (2500–5000 t km−2 yr−1), corn yields were 32.4 % lower than those in non-eroded sites. The spatial distribution of corn yield was opposite to that of soil erosion rate at catchment and slope scales. The relationship between corn yields and soil erosion rates had a negative linear relationship (p < 0.01), which was validated with acceptable accuracy. There was a positive linear relationship between corn yields and soil deposition rates without statistical significance (p > 0.05). These findings are valuable for assessing how soil erosion–deposition affects crop yields to implement countermeasures for controlling soil erosion and maintaining sustainable agricultural development.