Assessment of Soil Erosion and Its Impact on Agricultural Productivity by Using the RMMF Model and Local Perception: A Case Study of Rangun Watershed of Mid-Hills, Nepal

Soil erosion is a major concern for the environment and natural resources leading to a serious threat to agricultural productivity and one of the major causes of land degradation in the mid-hills region of Nepal. An accurate assessment of soil erosion is needed to reduce the problem of soil loss in highly fragile mountainous areas. The present study aimed to assess spatial soil loss rate and identified risk areas and their perceived impact on agricultural productivity by using the Revised Morgan–Morgan–Finney (RMMF) model and social survey in the Rangun watershed of Dadeldhura district, Nepal. Soil erosion was assessed by using data on soil, digital elevation model, rainfall, land use, and land cover visually interpreted from multitemporal satellite images, and ILWIS 3.3 academic software was used to perform the model. A household questionnaire survey (n = 120) and focus group discussion (n = 2) in identified risk areas were carried out to understand the people’s perception towards soil erosion and its impact on agricultural productivity. The predicted average soil erosions from the forest, agriculture, and barren land were 2.7 t ha−1 yr−1, 53.73 t ha−1 yr−1, and 462.59 t ha−1 yr−1, respectively. The erosion risk area under very low to low, moderate to moderately high, and high to very high covers 92.32%, 4.96%, and 2.73%, respectively. It indicates that the rate of soil erosion was lower in forest areas, whereas it was higher in the barren land. The cropped area of the watershed has been reduced by 2.96 ha−1 yr−1, and productivity has been decreased by 0.238 t ha−1 yr−1. The impacts such as removal of topsoil (weighted mean = 4.19) and gully formation (weighted mean = 3.56) were the highest perceived factors causing productivity decline due to erosion. People perceived the impact of erosion in agricultural productivity differently ( ∗ significant at P ≤ 0.05 ). The study concluded that, comparatively, barren and agricultural lands seem more susceptible to erosion, so the long-term conservation and management investment in susceptible areas for restoration, protection, and socioeconomic support contribute significantly to land rehabilitation in the Rangun watershed.

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Time Scale Effects and Interactions of Rainfall Erosivity and Cover Management Factors on Vineyard Soil Loss Erosion in the Semi-Arid Area of Southern Sicily

Water ◽

10.3390/w11050978 ◽

2019 ◽

Vol 11 (5) ◽

pp. 978 ◽

Cited By ~ 12

Author(s):

Giorgio Baiamonte ◽

Mario Minacapilli ◽

Agata Novara ◽

Luciano Gristina

Keyword(s):

Soil Erosion ◽

Soil Loss ◽

Scale Effects ◽

Management Practice ◽

Temporal Analysis ◽

Temporal Scale ◽

Rainfall Erosivity ◽

Erosion Risk ◽

Best Management ◽

The Impact

Several authors describe the effectiveness of cover crop management practice as an important tool to prevent soil erosion, but at the same time, they stress on the high soil loss variability due to the interaction of several factors characterized by large uncertainty. In this paper the Revised Universal Soil Loss Equation (RUSLE) model is applied to two Sicilian vineyards that are characterized by different topographic factors; one is subjected to Conventional Practice (CP) and the other to Best Management Practice (BMP). By using climatic input data at a high temporal scale resolution for the rainfall erosivity (R) factor, and remotely sensed imagery for the cover and management (C) factor, the importance of an appropriate R and C factor assessment and their inter and intra-annual interactions in determining soil erosion variability are showed. Different temporal analysis at ten-year, seasonal, monthly and event scales showed that results at events scales allow evidencing the interacting factors that determine erosion risk features which at other temporal scales of resolution can be hidden. The impact of BMP in preventing soil erosion is described in terms of average saved soil loss over the 10-year period of observation. The evaluation of soil erosion at a different temporal scale and its implications can help stakeholders and scientists formulate better soil conservation practices and agricultural management, and also consider that erosivity rates are expected to raise for the increase of rainfall intensity linked to climate change.

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Impacts of Land Cover and Greenness Change on Soil Loss and Erosion Risk in Damota Area Districts, Southern Ethiopia

Applied and Environmental Soil Science ◽

10.1155/2021/9148138 ◽

2021 ◽

Vol 2021 ◽

pp. 1-14

Author(s):

Mamush Masha ◽

Teshome Yirgu ◽

Mulugeta Debele

Keyword(s):

Soil Erosion ◽

Land Cover ◽

Water Conservation ◽

Soil Loss ◽

Soil And Water Conservation ◽

Southern Ethiopia ◽

Erosion Risk ◽

Aster Gdem ◽

Risk Areas ◽

Soil And Water

Soil erosion is a key problem in Ethiopia in view of tropical climate, lack of vegetation, and landscape relief. Therefore, soil and water conservation (SWC) measures have been practiced, but their impacts on soil loss have not been estimated adequately. The RUSLE modeling was applied using satellite imageries, ASTER GDEM, rainfall, and soil data to estimate total annual soil loss for a 100 km2 hilly and highly populated area in Ethiopia. Soil loss decreased in the Damota districts from 21 to 13 million tons from 2000 to 2020. Similarly, the average annual soil loss decreased by 36%. Very slight-risk areas (< 5 t ha−1 yr−1) increased from 42.66 to 53.72%, and very high-risk areas (> 50 t ha−1 yr−1) decreased from 12 to 5%. Soil and water conservation measures showed an important implication against soil erosion through improved land cover and landscape greenness. However, still, the rate of soil erosion is high compared to the soil loss tolerance of 1–6 t ha−1 yr−1 for the Ethiopian highlands.

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Soil Erosion Impact Assessment using USLE/GIS Approaches to Identify High Erosion Risk Areas in the Lowland Agricultural Watershed of Blue Nile Basin, Ethiopia

International Annals of Science ◽

10.21467/ias.8.1.120-129 ◽

2019 ◽

Vol 8 (1) ◽

pp. 120-129

Author(s):

Kidist Tsegaye ◽

Hailu Kendie Addis ◽

Ebrahim Esa Hassen

Keyword(s):

Soil Erosion ◽

Soil Loss ◽

Middle Part ◽

Agricultural Watershed ◽

Nile Basin ◽

Blue Nile ◽

Erosion Risk ◽

Management Interventions ◽

Blue Nile Basin ◽

Risk Areas

Erosion map of a watershed offers a wealth of knowledge and can be crucial for implementing site-specific management interventions. Thus, watershed-based soil erosion assessment was conducted to recognize erosion hotspot areas, while aiming to roughly calculate the average annual soil loss in Genda-wuha watershed, with a total area of 154,548.5 ha located in the northwest lowland of Blue Nile basin Ethiopia using USLE/GIS approach. Sixteen years of rainfall data, 53 soil sample data, a 30m by 30m digital elevation model (DEM), a land-use/land-cover map, and support practice factor were used to determine high erosion risk areas. The USLE parameters were integrated and analyzed using a raster calculator in the ArcGIS platform to predict and map the mean annual soil loss of Genda-wuha watershed. The result showed that the annual soil loss of the watershed extends from none in the lower and middle part of the watershed to 75.36 Megagram (Mg) ha-1yr-1 in the steeper parts of the watershed with a mean annual soil loss of 7.9 Mg ha-1yr-1. Most of the soil erosion affected areas are spatially situated in the upper steep slope parts of Genda-wuha watershed, which could be as a result of an increased slope gradient and length in the specified location. However, the majority of the watershed (82.62%) was estimated to be low erosion rates varying from 0 to 5 Mg ha–1 yr–1 and these areas correspond primarily to nearly flat landscapes of the watershed.

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Impact of Land Use and Land Cover Change on Soil Erosion Using Rusle Model And Gis: A Case of Temeji Watershed, Western Ethiopia

10.21203/rs.3.rs-100340/v1 ◽

2020 ◽

Author(s):

Mitiku Badasa Moisa ◽

Daniel Assefa Negash ◽

Biratu Bobo Merga ◽

Dessalegn Obsi Gemeda

Keyword(s):

Land Use ◽

Soil Erosion ◽

Land Cover ◽

Water Conservation ◽

Soil Loss ◽

Mitigation Strategies ◽

Cultivated Land ◽

Rusle Model ◽

Erosion Risk ◽

The Impact

Abstract BackgroundThe impact of Land Use/Land Cover (LULC) conversion on soil resources is getting global attention. Soil erosion is one the critical environmental problems worldwide with high severity in developing countries due to land degradation. This study integrates the Revised Universal Soil Loss Equation (RUSLE) model with a Geographic Information Systems (GIS) to estimate the impacts of LU/LC conversion on the mean annual soil loss in Temeji watershed. In this study, LU/LC change of Temeji watershed were assessed from 2000 to 2020 by using 2000 Landsat ETM+ and 2020 Landsat OLI/TIRS images and classified using supervised maximum likelihood classification algorithms. ResultsResults indicates that majority of the LU/LC in the study area is vulnerable to soil erosion. Our findings show that cultivated land had the highest average soil loss rate in Temeji watershed. High soil loss is observed when grass and forest land were converted into cultivated land with mean soil loss of 88.8t/ha/yr and 86.9t/ha/yr in 2020. Results revealed that about 6608.5ha (42.8%) and 8391.8ha (54.4%) were categorized under severe classes in 2000 and 2020, respectively.ConclusionsThe results can definitely support policy makers and environmental managers in implementation of soil and water conservation practices and erosion risk prevention and mitigation strategies in Temeji watershed.

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Estimation of Soil Erosion in Nepal Using a RUSLE Modeling and Geospatial Tool

Geosciences ◽

10.3390/geosciences9040147 ◽

2019 ◽

Vol 9 (4) ◽

pp. 147 ◽

Cited By ~ 13

Author(s):

Pooja Koirala ◽

Sudeep Thakuri ◽

Subesh Joshi ◽

Raju Chauhan

Keyword(s):

Soil Erosion ◽

Soil Loss ◽

Erosion Rate ◽

Agricultural Land ◽

Entire Area ◽

Barren Land ◽

Erosion Risk ◽

Soil Erosion Rate ◽

Severe Erosion ◽

The Mean

Soil erosion is a major issue, causing the loss of topsoil and fertility in agricultural land in mountainous terrain. Estimation of soil erosion in Nepal is essential because of its agriculture-dependent economy (contributing 36% to national GDP) and for preparing erosion control plans. The present study, for the first time, attempts to estimate the soil loss of Nepal through the application of the Revised Universal Soil Loss Equation (RUSLE) model. In addition, it analyzes the effect of Land Use and Land Cover (LULC) and slope ( β ) exposition on soil erosion. Nation-wide mean annual soil loss of Nepal is estimated at 25 t ha−1 yr−1 with a total of 369 million tonnes (mT) of potential soil loss. Soil erosion based on the physiographic region of the country shows that the Middle Mountains, High Mountains, High Himal, Chure, and Terai have mean erosion rates of 38.0, 32.0, 28.0, 7.0, and 0.1 t ha−1 yr−1. The soil erosion rate by basins showed that the annual erosions of the Karnali, Gandaki, Koshi, and Mahakali River basins are 135, 96, 79, and 15 mT, respectively. The mean soil erosion rate was significantly high (34 t ha−1 yr−1) for steep slopes (β > 26.8%) and the low (3 t ha−1 yr−1) for gentle slopes (β < 5%). Based on LULC, the mean erosion rate for barren land was the highest (40 t ha−1 yr−1), followed by agricultural land (29 t ha−1 yr−1), shrubland (25 t ha−1 yr−1), grassland (23 t ha−1 yr−1), and forests (22 t ha−1 yr−1). The entire area had been categorized into 6 erosion classes based on the erosion severity, and 11% of the area was found to be under a very severe erosion risk (> 80 t ha−1 yr−1) that urgently required reducing the risk of erosion.

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Watershed Prioritization Using Morphometric Analysis & RUSLE Model for Soil Conservation Planning, in Gilgel Abay Watershed, Ethiopia

10.21203/rs.3.rs-126047/v1 ◽

2020 ◽

Author(s):

Agumassie Genet Gela ◽

Daniel Ayalew Mengistu ◽

Seniet Maru

Keyword(s):

Factor Analysis ◽

Soil Erosion ◽

Morphometric Analysis ◽

Conservation Planning ◽

Soil Loss ◽

Equation Model ◽

Watershed Prioritization ◽

Erosion Risk ◽

Risk Areas ◽

Soil Loss Equation

Abstract Background: Soil erosion is the predominant global land degradation process which leads to a decline in ecosystem services and functions. The Gilgel Abay watershed is one of the watersheds in Upper Blue Nile basin characterized by rapid population growth, deforestation, overgrazing, soil erosion, waterlogging and flooding. These contribute the land and water resources of the watershed and its ecosystem are under high risk. This study was aimed to prioritize high erosion risk areas of Gilgel Abay watershed for soil and water conservation planning using the Revised Universal Soil Loss Equation model and morphometric analysis. Using the Revised Universal Soil Loss Equation model, Sub watershed Prioritization was done by computing the annual soil loss rate by considering the five model parameters. The compound factor analysis technique was used for prioritize sub-watersheds through morphometric analysis. Results: The result of estimated annual soil loss rates in Gilgel Abay watershed ranges from 0 to 781 t ha-1year-1, which is higher as compared to the limits of soil loss tolerance rates of the northern highlands of Ethiopia. From RUSLE model results, Sub watershed 4 was experiencing high erosion risks while, Subwatershed2 followed by sub watershed 4 are high erosion risk areas of compound factor analysis. Conclusion: The results of prioritization through both approaches show a quite alike output that is both identifies sub-watershed 4 and 2 as high erosion prone area. Therefore, both the results display a good efficiency in the assessment of erosion risks and giving priority in sub-watershed scale. Hence, the two approaches can be used to identify and delineate erosion-prone areas, and prioritize the areas for effective planning of sustainable land management options.

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Analysis of Ownership Data from Consolidated Land Threatened by Water Erosion in the Vlára Basin, Slovakia

Sustainability ◽

10.3390/su13010051 ◽

2020 ◽

Vol 13 (1) ◽

pp. 51

Author(s):

Alexandra Pagáč Mokrá ◽

Jakub Pagáč ◽

Zlatica Muchová ◽

František Petrovič

Keyword(s):

Soil Erosion ◽

Soil Loss ◽

Agricultural Land ◽

Water Erosion ◽

Land Consolidation ◽

Land Fragmentation ◽

Erosion Risk ◽

Definition Of ◽

The Relationship ◽

Soil Loss Equation

Water erosion is a phenomenon that significantly damages agricultural land. The current land fragmentation in Slovakia and the complete ambiguity of who owns it leads to a lack of responsibility to care for the land in its current condition, which could affect its sustainability in the future. The reason so much soil has eroded is obvious when looking at current land management, with large fields, a lack of windbreaks between them, and no barriers to prevent soil runoff. Land consolidation might be the solution. This paper seeks to evaluate redistributed land and, based on modeling by the Universal Soil Loss Equation (USLE) method, to assess the degree of soil erosion risk. Ownership data provided information on how many owners and what amount of area to consider, while taking into account new conditions regarding water erosion. The results indicate that 2488 plots of 1607 owners which represent 12% of the model area are still endangered by water erosion, even after the completion of the land consolidation project. The results also presented a way of evaluating the territory and aims to trigger a discussion regarding an unambiguous definition of responsibility in the relationship between owner and user.

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Evaluating of the spatial heterogeneity of soil loss tolerance and its effects on erosion risk in the carbonate areas of southern China

Solid Earth ◽

10.5194/se-8-661-2017 ◽

2017 ◽

Vol 8 (3) ◽

pp. 661-669 ◽

Cited By ~ 9

Author(s):

Yue Li ◽

Xiao Yong Bai ◽

Shi Jie Wang ◽

Luo Yi Qin ◽

Yi Chao Tian ◽

...

Keyword(s):

Soil Erosion ◽

Spatial Heterogeneity ◽

Soil Loss ◽

Carbonate Rock ◽

Southern China ◽

Clastic Rock ◽

Erosion Risk ◽

Soil Loss Tolerance ◽

Loss Tolerance ◽

The Relationship

Abstract. Soil loss tolerance (T value) is one of the criteria in determining the necessity of erosion control measures and ecological restoration strategy. However, the validity of this criterion in subtropical karst regions is strongly disputed. In this study, T value is calculated based on soil formation rate by using a digital distribution map of carbonate rock assemblage types. Results indicated a spatial heterogeneity and diversity in soil loss tolerance. Instead of only one criterion, a minimum of three criteria should be considered when investigating the carbonate areas of southern China because the one region, one T value concept may not be applicable to this region. T value is proportionate to the amount of argillaceous material, which determines the surface soil thickness of the formations in homogenous carbonate rock areas. Homogenous carbonate rock, carbonate rock intercalated with clastic rock areas and carbonate/clastic rock alternation areas have T values of 20, 50 and 100 t/(km2 a), and they are extremely, severely and moderately sensitive to soil erosion. Karst rocky desertification (KRD) is defined as extreme soil erosion and reflects the risks of erosion. Thus, the relationship between T value and erosion risk is determined using KRD as a parameter. The existence of KRD land is unrelated to the T value, although this parameter indicates erosion sensitivity. Erosion risk is strongly dependent on the relationship between real soil loss (RL) and T value rather than on either erosion intensity or the T value itself. If RL > > T, then the erosion risk is high despite of a low RL. Conversely, if T > > RL, then the soil is safe although RL is high. Overall, these findings may clarify the heterogeneity of T value and its effect on erosion risk in a karst environment.

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Assessing the Impact of Floods Disaster on Soil Erosion Risk Based on the RUSLE-GloSEM Approach in Western Iran

10.21203/rs.3.rs-775510/v1 ◽

2021 ◽

Author(s):

Morteza Akbari ◽

Ehsan Neamatollahi ◽

Hadi Memarian ◽

Mohammad Alizadeh Noughani

Keyword(s):

Climate Change ◽

Land Use ◽

Soil Erosion ◽

Land Use Change ◽

Agricultural Development ◽

Erosion Risk ◽

Before And After ◽

Global Soil ◽

Major Floods ◽

The Impact

Abstract Floods cause great damage to ecosystems and are among the main agents of soil erosion. Given the importance of soils for the functioning of ecosystems and development and improvement of bio-economic conditions, the risk and rate of soil erosion was assessed using the RUSLE model in Iran’s Lorestan province before and after a period of major floods in late 2018 and early 2019. Furthermore, soil erosion was calculated for current and future conditions based on the Global Soil Erosion Modeling Database (GloSEM). The results showed that agricultural development and land use change are the main causes of land degradation in the southern and central parts of the study area. The impact of floods was also significant since our evaluations showed that soil erosion increased from 4.12 t ha-1 yr-1 before the floods to 10.93 t ha-1 yr-1 afterwards. Field surveying using 64 ground control points determined that erodibility varies from 0.17 to 0.49% in the study area. Orchards, farms, rangelands and forests with moderate or low vegetation cover were the most vulnerable land uses to soil erosion. The GloSEM modeling results revealed that climate change is the main cause of change in the rate of soil erosion. Combined land use change-climate change simulation showed that soil erosion will increase considerably in the future under SSP1-RCP2.6, SSP2-RCP4.5, and SSP5-RCP8.5 scenarios. In the study area, both natural factors, i.e. climate change and human factors such as agricultural development, population growth, and overgrazing are the main drivers of soil erosion.

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