Uncertainty assessment of soil erodibility factor for revised universal soil loss equation

CATENA ◽  
2001 ◽  
Vol 46 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Guangxing Wang ◽  
George Gertner ◽  
Xianzhong Liu ◽  
Alan Anderson
1997 ◽  
Vol 12 (2) ◽  
pp. 55-58 ◽  
Author(s):  
Kim L. Fleming ◽  
William L. Powers ◽  
Alice J. Jones ◽  
Glenn A. Helmers

AbstractThe soil erodibility factor (K) of the Revised Universal Soil Loss Equation is currently considered a constant for all soils in the same type, regardless of production practice. To examine the effect of alternative production systems on the K-factor we compared pairs of alternatively and conventionally farmed fields on a Judson silt loam (Fine-silty, mixed, mesic Cumulic Hapludolls), a Yutan silty clay loam (Fine-silty, mixed, mesic Mollic Hapludalf), and a Wann fine sandy loam (Coarse-loamy, mixed, mesic Fluvaquentic Haplustolls). Soil cores were taken from the surface 10 cm and analyzed for organic matter, permeability, structure, and texture. These data were used to estimate K-factors from a nomograph. All soils in the study had a fine granular structure. Organic matter content and permeability were significantly higher for the alternatively managed field at every location, except for no difference in permeability on the Judson soil. However, the K-factor was significantly lower for the alternative system on the Judson soil. Of all the parameters, texture has the greatest influence in determining K-factors within the nomograph, with soils higher in silt being more erodible than soils higher in sand or clay. Thus, the influences of alternative production systems affected the Judson soil to a greater degree than other textures because of its higher inherent susceptibility to erosion. This study shows that alternative production systems affect the K-factor of some soil types and can reduce soil erodibility, and therefore should be considered when developing conservation plans.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Manish Olaniya ◽  
Pradip Kumar Bora ◽  
Susanta Das ◽  
Pukhrambam Helena Chanu

Abstract In absence of soil erosion plots for determination of erodibility index (K) for erosion models like Universal Soil Loss Equation (USLE) or Revised Universal Soil Loss Equation (RUSLE) to estimate soil erosion, empirical relations are used. In the present study, soil erodibility index was determined for entire Ri-bhoi district of Meghalaya based on soil physical and chemical properties through empirical relationship and presented in a map form. Dominant land uses of the district were identified through geo-spatial tools which were viz. agriculture, forest, jhum land and wasteland. Soil samples from surface depth (01–15 cm) were collected from areas of different dominant land uses. Twenty five sampling points were selected under each land use type and geo-coded them on the base map of Ri-bhoi district. Apart from K-index, Clay Ratio, Modified Clay Ratio and Critical Soil Organic Matter were also determined for understanding the effect of primary soil particles on erodibility. In agriculture land use system K-index values were found in the range of 0.08–0.41 with an average of 0.25 ± 0.02. In case of jhum, forest and wasteland these were in the range of 0.08–0.42 with an average of 0.20 ± 0.01; 0.09–0.40 with an average of 0.22 ± 0.02, and 0.10–0.34 with an average value of 0.23 ± 0.02, respectively. Clay ratio (2.74) and Modified clay ratio (2.41) were observed to be higher in forest LUS, lower clay ratio (1.97) and modified clay ratio (1.81) were found in the wasteland indicating erosion susceptibility in forested area. The values of Critical Level of Organic Matter (CLOM) for the district ranged from 4.72 to 16.56. Out of 100 samples, only one sample had CLOM value less than 5 and rest 99 samples had values more than 5 indicating that the soils of the district had moderate to stable soil structure and offer resistance to erosion. All the indices values of geo-coded points were then interpolated in the Arc-GIS environment to produce land use based maps for Ri-bhoi district of Meghalaya. As K-index is a quantitative parameter which is used in models, the index can be then interpolated for estimation of soil erosion through USLE or RUSLE for any given situation.


Author(s):  
Muhammad Rahman Djuwansah ◽  
Asep Mulyono

One of soil parameters that affects the rate of erosion is the soil erodibility. Soil erodibility studies had been conducted in one of the watershed of Lombok in 2015. The tests were carried out for five soil profiles by taking samples from each layers. Samples were analyzed for particles sizes and organic matter contents. The analysis was performed using two assessment models of soil erodibility, the Universal Soil Loss Equation (USLE) and Erosion Productivity Impact Calculator (EPIC) models. Obtained soil erodibility (K factors) values varied from 0.07 to 0.74 for USLE models and 0.18 to 0.46 for EPIC models. Statistical similarity (R) test resulted R=-0.28*10-19. It has indicated that there was no statistical difference between the results of both methods. The older volcanic rocks give a high erodibility factor. In this study, vertisols soils show a higher erodibility factor than other volcanic rocks, such as inceptisols, andisols and entisols soil. Lower soil organic matter and clay contents are the factors that influence high soil erodibility.Salah satu parameter tanah yang sangat berpengaruh terhadap besarnya erosi adalah faktor erodibilitas tanah. Studi erodibilitas tanah telah dilakukan di salah satu DAS di Pulau Lombok dengan uji lapangan. Uji lapangan dilakukan pada 5 profil tanah dan pengambilan sampel pada setiap lapisan untuk uji laboratorium terhadap kandungan partikel pasir, debu, liat dan bahan organik tanah. Analisis dilakukan menggunakan 2 model prediksi erodibilitas tanah yaitu model Universal Soil Loss Equation (USLE) dan Erosion Productivity Impact Calculator (EPIC). Nilai erodibilitas tanah dengan model USLE berkisar 0.07-0.74 dan 0.18-0.46 dengan model EPIC. Analisis statistik dengan tes R menghasilkan R=-0,28*10-19 yang menandakan nilai K yang diperoleh oleh kedua metode tidak berbeda. Endapan batuan vulkanik yang lebih tua di wilayah studi menghasilkan tingkat erodibilitas yang tinggi. Jenis tanah vertisols yang berasal dari endapan batuan volkanik tua menghasilkan tingkat erodibilitas tanah yang lebih tinggi dibandingkan jenis tanah lain yang terbentuk dari endapan batuan vulkanik seperti tanah inceptisols, andisols dan entisols. Semakin rendahnya kandungan bahan organik dan liat dalam tanah mengakibatkan semakin tingginya erodibilitas tanah.


1996 ◽  
Vol 32 (1) ◽  
pp. 91-101 ◽  
Author(s):  
M. Ruppenthal ◽  
D. E. Leihner ◽  
T. H. Hilger ◽  
J. A. Castillo F.

SUMMARYThe rainfall erosivity (R) and soil erodibility (K) factors of the Universal Soil Loss Equation (USLE) were determined on two sites in the Colombian Cauca Department over a five year period when rainfall was mostly lower than average. The results showed that the high erosion potential of the soils can be attributed more to high rain erosivity than soil erodibility. The R factor explained between 59 and 81% of the variation in soil loss recorded on continuously clean-tilled fallow plots. The erodibility of Inceptisols in the study region is classified as low. Values for soil erodibility (K) ranged from 0.012 to 0.015 (measured in SI units) in the fifth year of permanent bare fallowing. K factors were higher in the rainy than in the dry season. Soils, previously under grass vegetation, were very resistant to erosion in the first two years of bare fallowing. In the third year erodibility increased sharply and continued to increase steadily until the sixth year. K factors predicted by the USLE nomograph underestimated the empirically-determined erodibility of these highly aggregated clay soils.


2018 ◽  
Vol 192 ◽  
pp. 02041
Author(s):  
Yi-Hsin Liu ◽  
Kieu Anh Nguyen ◽  
Walter Chen ◽  
Jatuwat Wattanasetpong ◽  
Uma Seeboonruang

Tropical watersheds in Taiwan and Thailand face the same severe soil erosion problem that is increasing at an alarming rate. In order to evaluate the severity of soil erosion, we quantitatively investigate the issue using a common soil erosion model (Universal Soil Loss Equation, USLE) on the Shihmen reservoir watershed of Taiwan and the Lam Phra Ploeng basin of Thailand, and compare their respective erosion factors. The results show an interesting contrast between the two watersheds. Some of the factors (rainfall factor, slope-steepness factor) are higher in the Shihmen reservoir watershed, while others (soil erodibility factor, cover and management factor) are higher in the Lam Phra Ploeng basin. The net result is that these factors cancel each other out, and the amount of soil erosion of the two watersheds are very similar at 68.03 t/ha/yr and 67.57 t/ha/yr, respectively.


1975 ◽  
Vol 11 (4) ◽  
pp. 247-255 ◽  
Author(s):  
Guy E. Wilkinson

SUMMARYPrecipitation in Western Nigeria is principally from thunderstorms with sharp, high-intensity rainfall peaks. The time of occurrence of the peak intensity period in a rainstorm has an influence on whether or not runoff occurs in smaller storms. Runoff and soil loss on bare, cultivated Iwo soil are closely related to an EI30 erosivity index, modified by the time-position of the peak intensity. The soil erodibility factor in the universal soil-loss equation could be reasonably estimated from easily measured soil parameters.


1997 ◽  
Vol 77 (1) ◽  
pp. 33-40 ◽  
Author(s):  
B.G. McConkey ◽  
W. Nicholaichuk ◽  
H. Steppuhn ◽  
C. D. Reimer

Despite its importance to the degradation of the land resource, few estimates of soil loss or soil erodibility for water erosion from cropland have been made for the semiarid Brown soil zone of western Canada. To estimate these, we calibrated the event-based Modified Universal Soil Loss Equation with measured sediment yield for three 5-ha fields near Swift Current, Saskatchewan. The calibration used predetermined C, LS, P, and warm-season K factors with all erositivities and the K factors for other seasons optimized. Using this calibrated equation with 31 yr of measured runoff data, mean annual sediment yield for a conventional-tillage spring wheat-fallow cropping system on an undulating landscape (0 to 5% slopes) was estimated to be 0.8 Mg ha−1 yr−1. Estimated erosion from fallow land from 16 March to 15 April constituted 86% of the mean annual sediment yield. Erosion occurring during rainfall-runoff were relatively unimportant, accounting for about 4% of the estimated total sediment yield. An exceptionally severe rainstorm was predicted to have caused erosion of many Mg ha−1but the frequency of such events on a given field is too low to greatly affect mean annual erosion. Apparent field-scale soil erodibility was least in the winter (November to 15 March) when the soil would typically be frozen to the surface and was greatest in April when the soil would typically be partially frozen. Apparent erodibility in the summer and in late March was intermediate between those values. Key words: Erosion, runoff, snow, Universal Soil Loss Equation


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