Soil Erosion Assessment Using EPM Model in Onsar Wadi Basin in the Prerif Mountains, Morocco

This paper is dealing with soil erosion assessment using two different approaches: nuclear model and erosion potential method, also known as Gavrilovic's method. Complex valley systems on Titel Loess Plateau were selected for investigation. Radiocaesium is favored in many studies as an optimal erosion tracer due to its relatively long half-life, negligible renewal in the environment and strongly binding ability onto soil particles. The use of gamma-spectrometry in environmental testing laboratories acts as a precise and fast measurement technique for determination of 137Cs activity concentrations, without the need for complicate preparation of samples. Annual erosion and deposition rates were estimated according to three conversion models for uncultivated land: the profile distribution model with two years of dominant fallout of 137Cs (1963 and 1986) and the diffusion and migration model using WALLING software. The applied nuclear models were validated by comparison with erosion potential model which is the most relevant empirical model for erosion processes in torrent valleys. The obtained results indicate a good agreement with overall low values of average annual soil erosion rates on all soil profiles in the investigated area. Correlation analysis has determined the different influence of slope, terrain curvature, and vegetation index on the erosion models.

The main goal of the research is to assess soil erosion while analyzing the spatial distribution of its evolution using the EPM (erosion potential model). Situated northwest of the upper Oum-Rbaa watershed in Morocco, the Admer-Ezem watershed is part of the research area. Its climate is Mediterranean, ranging from semi-arid to subhumid bioclimate, which favors fairly scattered vegetation and poor soil. Separating the factors of complexity and interdependence in the analysis of erosion risk was made possible quickly and effectively by the Geographic Information System (GIS) integration of thematic maps of the various Gavrilovic Equation EPM factors with their databases. It also made it possible to evaluate each factor's influence and determine how much it contributed to soil loss. The priority of the various watershed regions was made possible by the use of Gavrilovic's calculations. This basin covers a total area of 197.59 km2, experiences relatively abundant rainfall (800 mm/year), and is subject to significant anthropogenic pressure. This will have an impact on the overexploitation of natural resources in general and soils in particular. Excessive use of agricultural land has led to its fragility and increased susceptibility to erosion. These natural and anthropogenic conditions have induced an intense erosive dynamic, which can be seen in its various forms (badlands, landslides, flows, concentrated active ravines…). The use of the "EPM" model for estimating soil losses approximates the severity of the erosion phenomenon. Soil loss due to water erosion according to the model used is estimated at 32.89 t/ha/year as the highest value and 0.11 t/ha/year as the lowest value. In addition, the analysis of these results made it possible, using GIS, to determine the factors that control water erosion.

The study aims to assess the rate of erosion that occurred in Manjunto Watershed and financial loss using Geographic Information System and Remote Sensing. Model used to determine the erosion is E30 models. The basis for the development of this model is to integrate with the slope of the slope between NDVI. The value of NDVI obtained from satellite imagery. Slope factor obtained through the DEM processing. To determine the amount of economic losses caused by erosion used the shadow prices. The amount of nutrients lost converted to fertilizer price. The results showed that the eroded catchment area has increased significantly. The rate of average annual erosion in the watershed Manjunto in 2000 amounted to 3 Mg ha-1 yr-1. The average erosion rate in the watershed Manjunto annual increase to 27 Mg ha-1 yr-1 in the year 2009. Economic losses due to erosion in 2009 was Rp200,000,- for one hectare. Total losses due to erosion for the total watershed area is Rp15,918,213,133, -. The main factor causing the high rate of erosion is high rainfall, slope and how to grow crops that do not pay attention to the rules of conservation.Keywords: Soil erosion, digital elevation model, GIS, remote sensing, valuation erosion[How to Cite: Gunawan G, D Sutjiningsih, H Soeryantono and S Widjanarko. 2013.Soil Erosion Prediction Using GIS and Remote Sensing on Manjunto Watershed Bengkulu-Indonesia. J Trop Soils 18 (2): 141-148. Doi: 10.5400/jts.2013.18.2.141][Permalink/DOI: www.dx.doi.org/10.5400/jts.2013.18.2.141]REFERENCESAksoy E, G Ozsoy and MS Dirim. 2009. Soil mapping approach in GIS using Landsat satellite imagery and DEM data. Afr J Agric Res 4: 1295-1302.Ananda J and G Herath. 2003. Soil erosion in developing countries: a socio-economic appraisal. J Environ Manage 68: 343-353.Ananda J, G Herath and A Chisholm. 2001. Determination of yield and Erosion Damage Functions Using Subjectivly Elicited Data: application to Smallholder Tea in Sri Lanka. 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Abstract: Climate change and human activities are seriously affecting the intensity and extent of soil erosion in the Pan-Third Pole region (PTP), which covers an area of approximately 5.14 × 107 km2. Accurate assessment of soil wind and water erosion is crucial for controlling soil degradation. In this study, soil water erosion in the PTP was estimated for 2018 using sampling units and the China Soil Loss Equation (CSLE), and soil wind erosion in the PTP from 1982 to 2020 was simulated using the Revised Soil Wind Erosion Equation (RWEQ), based on meteorological, soils, topographic, and remote sensing data. The results showed that: (1) Soil water erosion in the PTP mainly occurs in East Asia, South Asia, and the Black Sea coastal region, and the average soil wind erosion rate of the whole region is 263.4 t•km-2•a-1, and the average water erosion rate of the key erosion areas with water erosion rates exceeding 2,500 t•km-2•a-1 is 22.6 times higher than the average water erosion rate of the study area, and annual erosion amounted to 57.1×108t, accounting for 38.6% of total erosion amount. The soil water erosion rates of cropland, grassland, and forest were 525.7 t•km-2•a-1, 362.6 t•km-2•a-1, and 185.6 t•km-2•a-1, respectively. (2) Soil wind erosion in the PTP mainly occurs in cropland and grassland in semi-arid areas, and aeolian sand activity primarily occurring in extremely arid and arid areas (deserts), and the average multi-year soil wind erosion rate in regions other than deserts is 633.65 t•km-2•a-1, of which the mean soil wind erosion rate in the area where soil wind erosion rate is greater than 50 t•km-2•a-1 was 4,316.94 t•km-2•a-1, for cropland, grassland, and scrubland were 1,981.14 t•km-2•a-1, 3,815.05 t•km-2•a-1, and 4,010.95 t•km-2•a-1, respectively. (3) From 1982 to 2020, the soil wind erosion rate in the PTP decreased by 10.61 t•km-2•a-1. The proportion of the area with a decreasing trend was 19.53%, while the proportion of the area with an increasing trend was 28.35%. (4) Soil wind and water combined erosion mainly occur in cross-border regions of northern Syria, the Indus River Plain, the northern border of Iran and Afghanistan, the southwestern part of the Qinghai-Tibet Plateau, central Mongolia, the central part of the Loess Plateau, Inner Mongolia, and the bordering areas of the three eastern provinces, the average soil erosion rate of is 4,534.77 t•km-2•a-1, with the average soil erosion rates for grassland and cropland being 4,752.41 t•km-2•a-1 and 1,495.68 t•km-2•a-1, respectively. This study provided a comprehensive understanding of soil erosion (both soil wind and water erosion) in the PTP, and offered valuable data and decision-making support for current and future soil erosion prevention and ecological restoration projects.

The sediments resulting from the erosion of basins lead to the squandering of the soil, reduction of its infertility and decreasing of the quality of the water, and that is why the lifespan of the dams would be endangered because of the accumulation of the sediments. The goal of this research is to estimate erosion and sediment yield in Sangcharak basin by Erosion Potential Method (EPM), using GIS. For the purposes of quantifying the erosion intensity change has been done with the soil erosion maps from 2005 and recent state of erosion in 2014. Result of this paper showed that specific annual gross erosion on the Sangcharak territory was 775.34 (m³.km−2.y−1) in 2005 while in 2014 it was 914.24 (m³.km−2.y−1). Therefore, due to changes in intensity of erosion processes the specific annual gross erosion in catchment areas was increased by 138.89 (m³.km−2.y−1). Specific sediment yield in this area was 300.18 (m³.km−2.y−1) in 2005, while in 2014 was 349.01 (m³.km−2.y−1).

In recent decades, the quantification of Earth surface processes such as erosion, sediment transport, and deposition has gained increasing attention, with a focus on investigating their interplay across different spatial and temporal scales. This study contributes to address these challenges by combining in-situ cosmogenic 10Be isotopic analyses with a modified version of the Erosion Potential Model (EPM) to explore landscape and sediment dynamics in the Sfalassà stream catchment in Calabria, southern Italy.A total of 26 samples, including river sands of two different grain sizes and rock samples, were collected to estimate long-term erosion rates, sediment residence times (average exposure ages), and rates of vertical river dissection across the catchment. The adoption of 10Be cosmogenic nuclide enables a detailed understanding of erosion and sediment transport processes on millennial timescales, providing time frames for the main processes that have shaped the basin. The Sfalassà catchment, characterized by a diverse range of lithologies, geomorphological units, vegetation cover, land uses, and anthropogenic activities, was selected as a representative pilot basin in the central Mediterranean area. Sampling was conducted across the main channel and its tributaries to ensure comprehensive coverage. Field surveys formed the core of our sampling strategy, supplemented by aerial photo interpretation, GIS and thematic mapping analyses to enhance site selection.The EPM was upgraded using the catchment’s geological and pedological erodibility parameters. The specific weights of geological parameters and the differentiation of lithological classes assigned to various lithologies available in the literature were modified, trying to enhance the model accuracy for estimating medium-term erosion rates. This adjustment involved an integration of the spatial distribution of rock outcrops with that of major soil types, focusing on their varying susceptibility to surface erosion. Additionally, rainfall data were extrapolated at different elevations using a regression function of data from weather stations. In contrast to the EPM, the 10Be analyses provided precise and direct in situ measurements, enriching our understanding of catchment-scale erosion processes through the integration of methodologies.Despite operating on different temporal scales, the integration of isotopic data with the EPM may enhance the model’s accuracy. This synergy may provide a more robust framework for the quantification of sediment fluxes and erosion process modeling, contributing to a deeper understanding of sediment dynamics. This interdisciplinary approach not only sheds light on the connectivity between sediment source areas and the drainage system but can also suggest practical tools for assessing and managing sediment dynamics and coastal erosion risks. Based on the rates at which river sediments feed coastal areas, it highlights conditions of balance/unbalance in the sedimentary input, thus emphasizing broader geomorphological implications.The research is part of the "TECH4YOU – Technologies for climate change adaptation and quality of life improvement" project, funded by Next Generation EU (PNRR M4.C2.1.5). By combining geochronological techniques with numerical modeling, this study contributes to advancing methodologies for basin-scale investigations, offering replicable protocols applicable to diverse geo-environmental contexts and improving our understanding of sedimentary processes from source to sink.

Assessment of soil erosion and sediment yield changes using erosion potential model: case study of Sangcharak catchment in Fars, Iran

In the present study, two empirical models—the Erosion Potential Model (EPM) and the Revised Universal Soil Loss Equation (RUSLE)—in combination with Geographic Information Systems (GIS) have been applied to estimate soil erosion intensities and their spatial distribution within the Kolubara River Basin (3641 km²) in Serbia. Located in the western part of the country, the Kolubara River Basin covers 4.12% of Serbia's total area. The Kolubara River is the largest tributary of the Sava River and is classified as a medium-sized river within Serbia. The basin is known for its unfavorable water regime and is one of the most vulnerable regions in the country to natural hazards. The basin frequently experiences hazardous torrential floods resulting from short-duration, intense rainfall. These floods are closely linked to accelerated erosion processes in the upper part of the Kolubara basin.The current erosion conditions and the obtained erosion maps, as determined by the application of the aforementioned models, were compared to the existing Erosion Map of Serbia (Institute of Forestry and Wood Industry, Belgrade, 1983). The soil erosion models used in this study yielded results with varying magnitudes but showed significant correlations, indicating that both methods identified similar areas with high and low erosion rates. Both models effectively simulated the erosion phenomenon, demonstrating acceptable accuracy and enabling the identification of regions most susceptible to erosion and degradation.Despite the flash flood characteristics of the Kolubara basin and the potential for intense erosion processes, the results indicate that degradation in the basin has stabilized since 1983. Currently, intensive erosion affects 2.5% of the basin, moderate erosion impacts 40%, mild erosion is present on 26%, and very mild erosion occupies around 30%. The southwest, south, and southeast areas of the Kolubara basin are more prone to erosion, while the northern part of the basin and areas along river streams are expected to experience sediment accumulation. The reduction in erosion intensity since 1983 can be attributed to systematically implemented biological and technical anti-erosion measures, which have contributed to this improvement.However, the frequent occurrence of torrential floods in the Kolubara River basin suggests that the risk of future erosion remains significantly high. Therefore, integrated river basin management—including erosion and torrent control works—should be continuously implemented. In this regard, the USLE and EPM models should be utilized as valuable tools, given their simplicity, to identify erosion-prone regions within the basin where soil conservation and erosion control measures should be prioritized.

<p>High-resolution information on the processes and rates of soil erosion, transport, and deposition, offer important knowledge for soil erosion modelling, and the protection and sustainable management of soil. It helps improve the cross-scale understanding on aspects as aggregate breakdown, rill erosion, swelling and shrinking effects, and rill-network evolution. As a non-invasive, high-resolution, and cost as well as time-efficient method, Structure from Motion (SfM) presents a valuable tool to calculate soil loss, depict soil surface change detection, and offer high-resolution information on soil and soil erosion processes. Even though SfM shows in general higher erosion rates, due to the influence of non-erosive processes, the technique is altogether in good agreement with the sampling data at the outlet. We monitor soil erosion on multiple erosional plots and with spatial and temporal high-resolution photogrammetry to assess its feasibility over time.</p><p>For this purpose, we conduct 12 rainfall simulations on a three times one metre plot, on different sides, with different vegetation cover, tillage, and initial soil conditions. Seven to ten synchronized time-lapse cameras are set up around the plot, taking pictures every 10-60 seconds. The data thus obtained allow change detection assessment via digital elevation models of difference at least once per minute. The elevation change by SfM is validated via bulk density measurements, and sampling at the plot’s outlet assessing runoff, and sediment concentration at minute intervals. During an overflow experiment, we measure flow velocity via video using particle tracer and manually via colour tracer, gaining spatial and temporal distribution information on the flow velocity. Using low-cost sensors, we furthermore monitor the progress of the soil moisture and temperature during the whole rainfall simulation.</p><p>We present sampled and photogrammetric results based on a dozen rainfall simulations at the micro-scale with a very high temporal and spatial resolution. This gives an insight into spatial distribution and development of soil erosion processes on a sub-minute resolution. We compare these data to gain knowledge on the feasibility of temporal and spatial high-resolution SfM soil erosion assessment and their usability for the validation and calibration of process-based soil erosion models.</p>

Assessment of soil erosion and deposition rates in a Moroccan agricultural field using fallout 137Cs and 210Pbex

Soil erosion is an important geomorphological process with potential negative consequences especially on land agricultural potential. Unsuitable agricultural practices may increase soil erosion, leading to rapid loss of soil fertility and decrease of crop production. It is therefore important to correctly quantify soil erosion rates in order to adapt agricultural practices and implement proper conservation measures. This study attempts to assess the rill and interrill erosion in Romania, using the Romanian soil erosion model and GIS techniques. The database includes the digital terrain model, the soil map of Romania, the land use map of Romania and the rainfall erosivity regions. The results show that the high and very high erosion risk classes include 4.1% of the Romanian territory (9,627 km2). Most of this land is present in the hilly and plateau areas (Subcarpathians, Moldavian Plateau, Getic Plateau, Western Hills, Dobrogea Plateau). The model was validated by comparison of its predictions with long‐term erosion measurements from different locations in the country. Comparison with previous non‐GIS assessments of soil erosion at national level shows that the total estimated rill and interrill erosion in our study was very close to previous estimates. Comparison with the RUSLE 2015 model computed for Europe as a whole reveals that the two models assign almost 54% of their shared area to the same erosion class, while for 39% of the territory there is one class difference between the models. The results can be used for evaluations of erosion risk at national and regional scales.

A large effort has been devoted over the past century to assessing soil erosion using a variety of methods under a wide range of climatic conditions, soil types, land uses, topography, and others. Thus, we attempt to provide an analysis of national data of several soil erosion modeling and fingerprinting. The methodology adopted for this research is a review of scientific articles, conference papers and thesis on soil erosion, focusing more on categorization of the different soil erosion models and methods applied. Based on the statistical analysis provided by this review, the results are as follows: (i) Even though the threat of soil erosion is grave, the number of studies conducted to characterize and evaluate soil erosion in Morocco is limited. (ii) Studies on water erosion modeling are concentrated in the north of the country (Rif 32.89%, High Atlas 32.89%, Occidental Meseta 18.43% and Middle Atlas 10.53%). (iii) Water erosion models have been steadily developed and interfaced with GIS based approaches in recent decades. (iv) Although Morocco is geomorphologically and geologically varied (Rif, Middle and High Atlas, Mesetian and Saharan domain), several authors use soil erosion assessment models that ignore the unique characteristics of each study area and fail to adapt them to local conditions. (v) USLE (R) models have been widely used and modified over the past two decades and remain the most commonly used modeling tool today. (vi) The largest proportion of the erosion rate is concentrated in the Atlas and Rif mountains. (vii) Demonstration of a strong relationship between soil erosion rates with environmental factors and modeling conditions, and the lack of correlation with study area size and erosion rate. While the overall results show a relatively high variance, which cannot be explained by this combination of factors, it is partly related to the experimental conditions. This review is intended to support future soil erosion assessment and to facilitate the identification of priorities for soil erosion research in Morocco by supplying a state of the art for future targeted and comprehensive analyses to deal with the issue of soil erosion in Morocco.Keywords: Soil water erosion models, Fingerprinting methods, Literature review, Morocco.

Impact of land use and land cover change on soil erosion is still imperfectly understood, especially in northeastern China where severe soil erosion has occurred since the 1950s. It is important to identify temporal changes of soil erosion for the black soil region at different spatial scales. In the present study, potential soil erosion in northeastern China was estimated based on the Revised Universal Loss Equation by integrating satellite images, and the variability of soil erosion at different spatial scales following land use changes in 1980, 1990, 2000, 2010, and 2017 was analyzed. The regionally spatial patterns of soil loss coincided with the topography, rainfall erosivity, soil erodibility, and use patterns, and around 45% of soil loss came from arable land. Regionally, soil erosion rates increased from 1980 to 2010 and decreased from 2010 to 2017, ranging from 3.91 to 4.45 Mg ha−1 yr−1 with an average of 4.22 Mg ha−1 yr−1 in 1980–2017. Areas with a rate of soil erosion less than 1.41 Mg ha−1 yr−1 decreased from 1980 to 2010 and increased from 2010 to 2017, and the opposite changing patterns occurred in higher erosion classes. Arable land continuously increased at the expense of forest in the high-elevation and steep-slope areas from 1980 to 2010, and decreased from 2010 to 2017, resulting in increased areas with erosion rates higher than 7.05 Mg ha−1 yr−1. At a provincial scale, Liaoning Province experienced the highest soil erosion rate of 9.43 Mg ha−1 yr−1, followed by Jilin Province, the eastern Inner Mongolia Autonomous Region, and Heilongjiang Province. At a county scale, around 75% of the counties had a soil erosion rate higher than the tolerance level. The county numbers with higher erosion rate increased in 1980–2010 and decreased in 2010–2017, resulting from the sprawl and withdrawal of arable land.

The study is aimed at predicting soil erosion and investigate its spatial distribution in Souss basin area used EPM (erosion potential model), also known as Gavrilovic method, incorporating into GIS (geographic information system) software. The spatial distribution of soil erosion shows three main zones in the studied area (very slight, slight to moderate). The main factors in the EPM (soil erodibility, soil protection, slope, temperature and rainfall) were evaluated using GIS software. Data layers used in this study were created from digital elevation model (DEM), lithology maps, landsat 8 oli digital images, the highest amount of erosion occurred in the northeast regions, Results showed that about 87.84% of the study area is classified in low and very low to destructive erosion intensify, 12.15% of the study area was moderate potential soil losses.

The booming nature rubber industry has contributed to the extensive expansion of rubber plantations in the Lancang-Mekong River Basin over recent decades. To date, limited research has focused on the assessment of soil erosion caused by this expansion, resulting in a knowledge gap in the systematic and quantitative understanding of its ecological and hydrological impacts. This study evaluates soil erosion within rubber plantations and changes associated with their expansion by modifying the Revised Universal Soil Loss Equation (RUSLE) model in the middle section of the Lancang-Mekong River Basin from 2003 to 2022. The results show that: (1) rubber plantations have expanded rapidly, reaching a total area of 70.391 × 104 ha; (2) over the 20-year period, soil erosion trends within rubber plantations show both slight aggravation (affecting 45.377% of the area) and slight mitigation (affecting 35.859% of the area); (3) soil erosion in rubber plantations shows a pattern of decreasing, then increasing, and then decreasing again with stand age, with the lowest erosion (0.693 t·ha−1·yr−1) observed in plantations aged 10–15 years and the highest (1.017 t·ha−1·yr−1) in those aged 15–20 years; (4) rubber plantation expansion led to a fivefold increase in soil erosion with an average soil loss of 0.148 t·ha−1·yr−1 in the non-expansion areas and 0.902 t·ha−1·yr−1 in expansion areas; and (5) slope had the most significant impact on soil erosion. Interactions between slope and other factors —especially slope and soil type (Q > 0.777)—consistently demonstrated strong explanatory power. This research provides valuable insights for the assessment and management of soil erosion in rubber plantations.