A new approach for calculating the slope length factor in the Revised Universal Soil Loss Equation

Abrupt changes in climatic factors, exploitation of natural resources, and land degradation contribute to soil erosion. This study provides the first comprehensive analysis of annual soil erosion dynamics in Pakistan for 2005 and 2015 using publically available climatic, topographic, soil type, and land cover geospatial datasets at 1 km spatial resolution. A well-accepted and widely applied Revised Universal Soil Loss Equation (RUSLE) was implemented for the annual soil erosion estimations and mapping by incorporating six factors; rainfall erosivity (R), soil erodibility (K), slope-length (L), slope-steepness (S), cover management (C) and conservation practice (P). We used a cross tabular or change matrix method to assess the annual soil erosion (ton/ha/year) changes (2005-2015) in terms of areas and spatial distriburtions in four soil erosion classes; i.e. Low (<1), Medium (1–5], High (5-20], and Very high (>20). Major findings of this paper indicated that, at the national scale, an estimated annual soil erosion of 1.79 ± 11.52 ton/ha/year (mean ± standard deviation) was observed in 2005, which increased to 2.47 ±18.14 ton/ha/year in 2015. Among seven administrative units of Pakistan, in Azad Jammu & Kashmir, the average soil erosion doubled from 14.44 ± 35.70 ton/ha/year in 2005 to 28.03 ± 68.24 ton/ha/year in 2015. Spatially explicit and temporal annual analysis of soil erosion provided in this study is essential for various purposes, including the soil conservation and management practices, environmental impact assessment studies, among others.

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Digital mapping of RUSLE slope length and steepness factor across New South Wales, Australia

Soil Research ◽

10.1071/sr14208 ◽

2015 ◽

Vol 53 (2) ◽

pp. 216 ◽

Cited By ~ 15

Author(s):

Xihua Yang

Keyword(s):

Land Use Planning ◽

Soil Loss ◽

Overland Flow ◽

New South ◽

New South Wales ◽

Slope Angle ◽

Universal Soil Loss Equation ◽

Slope Length ◽

South Wales ◽

Soil Loss Equation

The Universal Soil Loss Equation (USLE) and its main derivate, the Revised Universal Soil Loss Equation (RUSLE), are widely used in estimating hillslope erosion. The effects of topography on hillslope erosion are estimated through the product of slope length (L) and slope steepness (S) subfactors, or LS factor, which often contains the highest detail and plays the most influential role in RUSLE. However, current LS maps in New South Wales (NSW) are either incomplete (e.g. point-based) or too coarse (e.g. 250 m), limiting RUSLE-based applications. The aim of this study was to develop automated procedures in a geographic information system (GIS) to estimate and map the LS factor across NSW. The method was based on RUSLE specifications and it incorporated a variable cutoff slope angle, which improves the detection of the beginning and end of each slope length. An overland-flow length algorithm for L subfactor calculation was applied through iterative slope-length cumulation and maximum downhill slope angle. Automated GIS scripts have been developed for LS factor calculation so that the only required input data are digital elevation models (DEMs). Hydrologically corrected DEMs were used for LS factor calculation on a catchment basis, then merged to form a seamless LS-factor digital map for NSW with a spatial resolution ~30 m (or 1 s). The modelled LS values were compared with the reference LS values, and the coefficient of efficiency reached 0.97. The high-resolution digital LS map produced is now being used along with other RUSLE factors in hillslope erosion modelling and land-use planning at local and regional scales across NSW.

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An improved method for calculating slope length (λ) and the LS parameters of the Revised Universal Soil Loss Equation for large watersheds

Geoderma ◽

10.1016/j.geoderma.2017.08.006 ◽

2017 ◽

Vol 308 ◽

pp. 36-45 ◽

Cited By ~ 18

Author(s):

Hongming Zhang ◽

Jicheng Wei ◽

Qinke Yang ◽

Jantiene E.M. Baartman ◽

Lingtong Gai ◽

...

Keyword(s):

Soil Loss ◽

Universal Soil Loss Equation ◽

Improved Method ◽

Slope Length ◽

Soil Loss Equation

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Design and Implementation of Regional LS Factor Computing Tool Based on GIS and Array Operation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.394.509 ◽

2013 ◽

Vol 394 ◽

pp. 509-514

Author(s):

Hong Ming Zhang ◽

Qin Ke Yang ◽

Shu Qin Li ◽

Mei Li Wang ◽

Ming Ying ◽

...

Keyword(s):

Soil Loss ◽

Large Scale ◽

Universal Soil Loss Equation ◽

Graphic User Interface ◽

Slope Length ◽

Long Time ◽

Area Unit ◽

User Friendly ◽

Gis Software ◽

Soil Loss Equation

For over 40 years, the universal soil loss equation (USLE) and its revised version the revised universal soil loss equation (RUSLE) have been used all over the world for soil mean annual loss per area unit. Because of the watershed erosion models are under developing, many researchers applied the USLE and RUSLE to estimate soil loss in watershed estimations. However, a major limitation is the difficulty in extracting the LS factor. The geographic information system-based (GIS-based) methods which have been developed for estimating the slope length for USLE and RUSLE model also have limitations. A series of ARC/INFO AML program was created that can calculate LS factor for the USLE, however the program need a very long time to run in wide-ranging areas. The flowpath and cumulative cell length-based method (FCL) overcomes this disadvantage but does not consider the following questions: (1) Some original AML program functions are not achieved, so results are different. (2) Using USLE to calculate LS factor that do not adapt to the erosion environment of China. (3) There isnt a friendly graphic user interface. The purpose of this research was to overcome these limitations and extend the FCL method through Integrating CSLE equation. We developed a LS calculation tool (LS-TOOL) in Microsofts .NET environment using C# with a user-friendly interface. Comparing the LS factor calculated with the FCL method and AML method, LS factor values generated by using LS-TOOL method delivers improved results. The LS-TOOL algorithm can automatically calculate slope length, slope steepness, L factor, S factor, and LS factors, providing the results as ASCII files which can be easily used in some GIS software. This study is an important step forward in conducting fast large-scale erosion evaluation.

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Assessment of Soil Loss using Revised Universal Soil Loss Equation (RUSLE): A Remote Sensing and GIS Approach

10.21523/gcj1.18020105 ◽

2018 ◽

Vol 2 (1) ◽

pp. 65-75 ◽

Cited By ~ 4

Author(s):

Ajaykumar Kadam ◽

B. N. Umrikar ◽

R. N. Sankhua

Keyword(s):

Remote Sensing ◽

Soil Loss ◽

Remote Sensing Data ◽

Tropical Rainfall Measuring Mission ◽

Remote Sensing And Gis ◽

Universal Soil Loss Equation ◽

Rainfall Erosivity ◽

Slope Length ◽

Gis Environment ◽

Soil Loss Equation

A comprehensive methodology that combines Revised Universal Soil Loss Equation (RUSLE), Remote Sensing data and Geographic Information System (GIS) techniques was used to determine the soil loss vulnerability of an agriculture mountainous watershed in Maharashtra, India. The spatial variation in rate of annual soil loss was obtained by integrating raster derived parameter in GIS environment. The thematic layers such as TRMM [Tropical Rainfall Measuring Mission] derived rainfall erosivity (R), soil erodibility (K), GDEM based slope length and steepness (LS), land cover management (C) and factors of conservation practices (P) were calculated to identify their effects on average annual soil loss. The highest potential of estimated soil loss was 688.397 t/ha/yr. The mean annual soil loss is 1.26 t/ha/yr and highest soil loss occurs on the main watercourse, since high slope length and steepness. The spatial soil loss maps prepared with RUSLE method using remote sensing and GIS can be helpful as a lead idea in arising plans for land use development and administration in the ecologically sensitive hilly areas.

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Runoff dependent erosivity and slope length factors suitable for modelling annual erosion using the Universal Soil Loss Equation

Hydrological Processes ◽

10.1002/hyp.6493 ◽

2007 ◽

Vol 21 (20) ◽

pp. 2681-2689 ◽

Cited By ~ 35

Author(s):

P. I. A. Kinnell

Keyword(s):

Soil Loss ◽

Universal Soil Loss Equation ◽

Slope Length ◽

Soil Loss Equation

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Assessment of Soil Erosion Hazard in Prambanan District Using RUSLE (Revised Universal Soil Loss Equation)

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/884/1/012010 ◽

2021 ◽

Vol 884 (1) ◽

pp. 012010

Author(s):

S. A Mulya ◽

N. Khotimah

Keyword(s):

Soil Loss ◽

Hazard Index ◽

Universal Soil Loss Equation ◽

Annual Rainfall ◽

Rainfall Erosivity ◽

Slope Length ◽

Erosion Hazard ◽

Erosion Processes ◽

Factor C ◽

Soil Loss Equation

Abstract Prambanan District which located in Daerah Istimewa Yogyakarta Province has the potential for land degradation due to erosion processes. With the characteristics of annual rainfall more than 2000 mm / year, topography with a slope of more than 20% in upland areas, as well as the conversion of upland to dryland agriculture are factors that can trigger the erosion process more quickly. If the rate of erosion speed exceeds the ability of the soil to regenerate the soil body, its productivity will be disrupted and accelerate the formation of critical soil. Therefore, it is necessary to know the estimated rate of erosion, tolerable distribution of erosion, and the potential danger of erosion that occurs. The purpose of this study was to (1) predict the rate of erosion, (2) calculate the permissible erosion value, (3) identify the rate & index of erosion hazard. Data were collected using field surveys and soil sampling using stratified random sampling techniques with land units as the unit of analysis. The value of erosion was predicted using the Revised Universal Soil Loss Equation (RUSLE) method. The RUSLE method is described by the following equation, A=R*K*L*S*C*P, where; A as estimated averages annual loss of soil, R is the rainfall erosivity factor, K is the soil erodibility factor, LS is the slope length factor, C is the cover management factor, & P is the conservation practice factor. The results showed that the erosion value ranged from 0.39 - 268.55 tons/ha/year. Permissible erosion ranges from 8.4 – 15 tons/ha/year for Latosol and 27.4 ton/ha/year for Regosol. The Rate of Erosion Hazard is dominated by moderate erosion, covering an area of 1330.7 ha or 31.8% of the total area. The Erosion Hazard Index is dominated by the low class (<1.0) which is covered over 2703.1 ha or 64.61% of the total area.

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EFFECTS OF POTATO CROPPING PRACTICES ON WATER RUNOFF AND SOIL EROSION

Canadian Journal of Soil Science ◽

10.4141/cjss90-016 ◽

1990 ◽

Vol 70 (2) ◽

pp. 137-148 ◽

Cited By ~ 24

Author(s):

T. L. CHOW ◽

H. CORMIER ◽

J. L. DAIGLE ◽

I. GHANEM

Keyword(s):

Soil Loss ◽

Universal Soil Loss Equation ◽

Water Runoff ◽

Slope Length ◽

Cropping Practices ◽

Erosion Index ◽

Factor C ◽

Runoff And Soil Loss ◽

Soil Loss Equation ◽

Rainfall Erosion

Using runoff-erosion plots (10 m wide × 30 m long), the effects of cropping practices on surface runoff and soil loss were examined on a Hommesville gravelly loam soil to evaluate the applicability of the Universal Soil Loss Equation in New Brunswick. The amount of water runoff and soil loss from continuous fallow, up-and-down slope planting of potatoes (Solanum tuberosum), and clover (Trifolium pratense) on 8 and 11% slopes were measured from 1983 to 1985. In addition, runoff and soil loss from contour planting of potatoes were measured on the 11% slope. Slope planting of potatoes resulted in higher runoff and soil loss than on fallow plots. There was considerable reduction in runoff and soil loss when potatoes were planted along the contour. Runoff and soil loss under clover were negligible. Rainfall erosion index (R) and slope length and steepness (LS) correlated well with the measured soil losses. However, both the measured soil credibility factor (K) and the cover and management factor (C) deviated markedly from the current values used for conservation planning. Key words: Universal Soil Loss Equation, rainfall erosion index, topographic factor, soil erodibility factor, cover and management factor, support practice factor

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ALTERNATIVA PARA O CÁLCULO AUTOMÁTICO E ESPACIALIZADO DO FATOR TOPOGRÁFICO DA USLE EM BACIAS HIDROGRÁFICAS

Irriga ◽

10.15809/irriga.2018v1n2p6-13 ◽

2018 ◽

Vol 1 (2) ◽

pp. 6-13

Author(s):

FRANCISCO EMANOEL FIRMINO GOMES ◽

George Leite Mamede ◽

Fernando Bezerra Lopes

Keyword(s):

Soil Loss ◽

Shuttle Radar Topography Mission ◽

Universal Soil Loss Equation ◽

High Complexity ◽

Slope Length ◽

Topographic Factor ◽

Digital Elevation ◽

Elevation Model ◽

E Mail ◽

Soil Loss Equation

ALTERNATIVA PARA O CÁLCULO AUTOMÁTICO E ESPACIALIZADO DO FATOR TOPOGRÁFICO DA USLE EM BACIAS HIDROGRÁFICAS FRANCISCO EMANOEL FIRMINO GOMES1; GEORGE LEITE MAMEDE2 E FERNANDO BEZERRA LOPES3 1Departamento de engenharia agrícola/UFC, Doutorando em engenharia agrícola, Fortaleza, CE, Fone:(85)99238-2819, CEP:60440-900, e-mail: [email protected]. 2Instituto de Engenharias e Desenvolvimento Sustentável/ UNILAB, Professor Doutor, Redenção, CE, CEP: 62790-000, e-mail: [email protected] 3Departamento de Engenharia Agrícola, UFC, Professor Doutor, Fortaleza, CE, CEP:60440-900, e-mail: [email protected] 1 RESUMO Dentre os fatores da Universal Soil Loss Equation (USLE), o fator topográfico é que menos se aproxima da realidade e, em geral, os modelos apresentam elevada complexidade para sua determinação. Neste estudo, portanto objetivou-se calcular o fator topográfico da USLE de maneira simplificada usando técnicas de Sistema de Informações Geográficas (SIG). Para tanto, foi utilizado dados do Modelo Digital de Elevação - MDE obtido a partir do (SRTM -Shuttle Radar Topography Mission), assim foram calculadas as declividades e os comprimentos de rampas usando processamento dos dados matriciais do MDE, para então estimar o fator topográfico. Os valores de fator topográfico variaram de 0,21 a 9,88 com média de 1,97. As técnicas de sistema de informação geográficas mostraram-se eficientes para o cálculo do fator topográfico a partir do MDE. Palavras-chave: erosão, topografia de encosta, geoprocessamento. GOMES, F. E. F.; MAMEDE, G. L.; LOPES, F. B. ALTERNATIVE FOR THE AUTOMATIC AND SPACIALIZATION OF USLE TOPOGRAPHIC FACTOR IN WATERSHEDS 2 ABSTRACT Among the factors of the Universal Soil Loss Equation (USLE), the topographic factor is that it is less close to reality and, usually, the models used for its determination presents high complexity. In this study, therefore, the main objective was to calculate the topographic factor of the USLE in a simplified way using techniques geographic information system (sig). For that, data from the Digital Elevation Model – DEM was used, derived from the SRTM (Shuttle Radar Topography Mission), so slopes and slope length were calculated by processing of the DEM matrix data, so the topographic factor was estimated. The topographic factor values varying from 0.21 to 9.88 with an average of 1.97. The GIS techniques showed efficient for estimating the topographic factor derived from DEM data base. Keywords: erosion, topography of hillside, geoprocessing.

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