Table of Contents
How do you calculate rainfall erosivity factor?
The rainfall erosivity is calculated by multiplying the kinetic energy by the maximum rainfall intensity during a period of 30-minutes for each rainstorm. The R-factor accumulates the rainfall erosivity of individual rainstorm events and averages this value over multiple years.
What is Erosivity rainfall?
Rainfall erosivity is the capability of rainfall to cause soil loss from hillslopes by water.
What is Erosivity waiver?
EPA’s Small Construction Rainfall Erosivity Waiver This waiver applies to small construction sites between 1 and 5 acres, and allows permitting authorities to waive those sites that do not have adverse water quality impacts. Dischargers eligible for this waiver are exempt from Construction General Permit Coverage.
What is soil Erosivity?
Erodibility describes or is a measure of the inherent resistance of geologic materials (soils and rocks) to erosion. Highly erodible geologic materials are readily displaced and transported by water.
What are Erosivity factors?
The rainfall erosivity factor (R-factor) is based on kinetic energy considerations of falling rain (Whelan 1980) and represents a measure of the erosive force and intensity of rain in a normal year (Goldman et al. 1986).
What is the unit of rainfall erosivity factor?
The event erosivity EI30 (MJ mm ha− 1 h− 1) is defined as:(2) E I 30 = ∑ r = 1 0 e r v r I 30 where er is the unit rainfall energy (MJ ha− 1 mm− 1) and vr is the rainfall volume (mm) during a time period r. I30 is the maximum rainfall intensity during a 30-min period of the rainfall event (mm h− 1).
What are the factors of Erosivity?
The most important erosion factors include the climatic, hydrological, topographic, soil, geological and vegetation conditions, as well as the economic and technical and the socioeconomic conditions of the human society.
What is LS factor in RUSLE?
L is the slope length factor, representing the effect of slope length on erosion. It is the ratio of soil loss from the field slope length to that from a 72.6-foot (22.1-meter) length on the same soil type and gradient.
What is topographic factor LS?
Topography: LS-Factor The S-factor measures the effect of slope steepness, and the L-factor defines the impact of slope length. The combined LS-factor describes the effect of topography on soil erosion.
How do you calculate Rusle?
RUSLE maintains the same empirically based equation as USLE to compute 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 slope length factor, S is the slope steepness factor, C is a cover management factor, and …
How do you calculate RUSLE?
How is Usle calculated?
The Universal Soil Loss Equation, or USLE, predicts the average annual soil loss “A” per unit area. 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.
What are the 6 RUSLE factors?
There are six factors parameter maps were considered in RUSLE; rainfall erosivity factor (R), soil erodibility (K), slope length and steepness (LS), cover management(C) and conservation practice (P).
What is C factor in USLE?
The C factor is a ratio comparing the soil loss from land under a specific crop and management system to the corresponding loss from continuously fallow and tilled land.
How do you calculate C Factor?
To calculate the C Factor, measure the flow, pipe diameter, distance between two pressure gauges, and the friction or energy loss of the water between the gauges.
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 …
What is C-Factor?
The cavity configuration or C-factor is defined as the ratio of the bonded to the unbonded surface area. 17. During light-induced polymerization of resin composite, the shrinkage forces in high C-factor cavities cannot be relieved by resin flow, resulting in the debonding of one or more walls.