Universal Soil Loss Equation (USLE) A = R x K x LS x C x P. A represents the potential long-term average annual soil loss in tonnes per hectare (tons per acre) per year. This is the amount, which is compared to the "tolerable soil loss" limits. R is the rainfall and runoff factor by geographic location as given in Table 1.
What does USLE stand for?
Background. The Universal Soil Loss Equation (USLE) predicts the long-term average annual rate of erosion on a field slope based on rainfall pattern, soil type, topography, crop system and management practices. USLE only predicts the amount of soil loss that results from sheet or rill erosion on a single slope and does not account ...
What are the components of the USLE equation?
The equation includes the rainfall erosivity factor (R), the soil erodibility factor (K), the topographic factors (L and S) and the cropping management factors (C and P). The equation takes the simple product form: The USLE has another concept of experimental importance, the unit plot concept.
How was the USLE developed?
The USLE was developed from erosion plot and rainfall simulator experiments. The USLE is composed of six factors to predict the long-term average annual soil loss (A). The equation includes the rainfall erosivity factor (R), the soil erodibility factor (K), the topographic factors (L and S) and the cropping management factors (C and P).
What is the soil loss value generated from the USLE?
The soil loss value generated from the USLE equation is used to determine the "soil erosion rating value" in the calculation of the Phosphorus Index. See the OMAFRA Factsheet Determining the Phosphorus Index for a Field, Order No. 05-067. Universal Soil Loss Equation (USLE) A = R x K x LS x C x P
What is the formula for USLE?
The USLE is an empirically based equation, derived from a large mass of field data, especially erosion plots and rainfall simulator experiments, and computes sheet and rill erosion as follows: A=RKLSCP where A is computed soil loss, R is the rainfall-runoff erosivity factor, K is a soil erodibility factor, L is the ...
How is USLE LS factor calculated?
The equations for calculating LS in the RUSLE are:(1) LS = L ⋅ S (2) L = λ / 22.13 m (3) m = β / 1 + β (4) β = sin θ / 3 ⋅ sin θ 0.8 + 0.56 (5) S = 10.8 ⋅ sin θ + 0.03 θ < 9 % S = 16.8 ⋅ sin θ − 0.5 θ ≥ 9 % where λ is the slope length (m), m is a variable length-slope exponent, β is a factor that varies with slope ...
What does the USLE estimate?
The Universal Soil Loss Equation (USLE) is hailed as one of the most significant developments in soil and water conservation in the 20 thcentury. It is an empirical technology that has been applied around the world to estimate soil erosion by raindrop impact and surface runoff.
What is the R factor in USLE?
The rainfall erosivity factor (R factor) is one of six erosion factors in the Universal Soil Loss Equation (USLE), which together reflect the combined effects that cause soil loss by rill and interrill erosion on hillslopes by precipitation.
What are the limitations of USLE?
The most commonly cited limitation of the (R)USLE models is their reduced applicability to regions outside of the United States of America (Aksoy and Kavvas, 2005; Naipal et al., 2015; Sadeghi et al., 2014). The original USLE was formulated based on soil erosion studies on agricultural land in the USA.
Who developed USLE?
The USLE was developed in the U.S., based on soil erosion data collected beginning in the 1930s by the U.S. Department of Agriculture (USDA) Soil Conservation Service (now the USDA Natural Resources Conservation Service).
What does USLE stand for?
USLEAcronymDefinitionUSLEUniversal Soil Loss Equation
What is the difference between USLE and RUSLE?
RUSLE also captures better than USLE that long rains can saturate the soil, leading to reduced intake and greater erosional runoff. In contrast with USLE, RUSLE can handle converging and diverging terrain and considers areas with net sedimentation.
How do you calculate the rate of soil erosion?
The equation is A = R x K x L x S x C x P and multiplies various factors to arrive at the annual erosion rate. The R factor is based on rainfall and runoff, while K is the soil erodibility factor and depends on the type of soil.
How is R factor calculated?
It is simply the thickness of the insulation in inches divided by the thermal conductivity of the insulation. For example, a two inch thick sheet of insulation with a thermal conductivity of 0.25 Btu•in/h•ft2•°F has an R-value equal to 2 divided by 0.25 or 8.0.
What is the standard length and slope of the USLE plot USLE?
The soil erodibility factor, K, is the average soil loss, in tons per acre, per 100 ft–tons per acre of rainfall erosivity standardized for a plot of land with 9% slope, 72.6 ft long, under continuous cultivation (Fig. 11-2).
What is conservation practice factor?
The ratio of soil loss for contouring, strip cropping, or terracing, to that for up and down the slope farming, as used in the soil-loss equation.
What is USLE model?
The USLE or one of its derivatives are main models used by United States government agencies to measure water erosion. The USLE was developed in the U.S., based on soil erosion data collected beginning in the 1930s by the U.S. Department of Agriculture ( USDA) Soil Conservation Service (now the USDA Natural Resources Conservation Service ).
How many factors are in the USLE?
The USLE was developed from erosion plot and rainfall simulator experiments. The USLE is composed of six factors to predict the long-term average annual soil loss (A). The equation includes the rainfall erosivity factor (R), the soil erodibility factor (K), the topographic factors (L and S) and the cropping management factors (C and P). The equation takes the simple product form:
Most recent answer
Hi. What is your model area? You can fined K factor values for several soil types in original methodology by Wischmeier and Smith (1978) and other methodologies for several countries. Or you can use K factor map of EU: https://esdac.jrc.ec.europa.eu/content/soil-erodibility-k-factor-high-resolution-dataset-europe
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If by 'soil type" you mean soil series, you should be able to look up the textural classification. You could also refer to the soil survey if you have the location of the soil. Neither of these are as good as a measured texture, but they may get you close enough, depending on what it is you are using the information for.
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How can I calculate RUSLE K-factor (erodibility) factor without soil structure information?
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What is Rusle2 erosion prediction?
RUSLE2 is new, advanced erosion prediction technology that uses the familiar USLE empirical structure proven by more than five decades of use in the Universal Soil Loss Equation (USLE) and RUSLE1. Modern erosion and computer science is used in RUSLE2 to greatly extend the basic USLE structure.
What is Rusle1 and Rusle2 used for?
RUSLE1 and RUSLE2 are used by government agencies around the world to assess and inventory erosion to assist public policy development.
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