Section 4: Soil and Water Conservation Engineering
Soil and Water Erosion
Subtopic: Soil loss estimation
Question Statement:
In the Universal Soil Loss Equation ($A = R K LS C P$), the standard USLE unit plot on which soil erodibility factor $K$ is calibrated has a length of:
Options:
(A) $22.13\text{ m}$ ($72.6\text{ ft}$) on a $9\%$ uniform slope
(B) $50.0\text{ m}$ on a $5\%$ uniform slope
(C) $10.0\text{ m}$ on a $12\%$ uniform slope
(D) $30.5\text{ m}$ on an $8\%$ uniform slope
Answer Key:
A
Step-by-Step Solution & Explanation
The standard unit plot defined by Wischmeier and Smith is $22.13\text{ m}$ ($72.6\text{ ft}$) long on a continuous $9\%$ slope, maintained in continuous fallow tilled up and down the slope with $LS = 1.0, C = 1.0,$ and $P = 1.0$.