# Universal Soil Loss

Written by Jerry Ratzlaff on . Posted in Geotechnical Engineering

Universal soil loss, abbreviated as USLE, predicts the potential long-term average annual soil loss per unit area.

## Universal Soil Loss Formula

 $$\large{ A = R \; K \; LS \; C \; P }$$

### Where:

 Units English Metric $$\large{ A }$$ = estimated annual soil loss $$\large{tons-acre-yr}$$ $$\large{tonnes-hectare-yr}$$ $$\large{ C }$$ = crop/vegitation and management factor $$\large{dimensionless}$$ $$\large{ R }$$ = R factor - rainfall and runoff by geographic location (the summed erosive potential of all rainfall events in a year) $$\large{dimensionless}$$ $$\large{ LS }$$ = slope length-gradient factor $$\large{dimensionless}$$ $$\large{ P }$$ = support practice factor (reflects the effects of particles that will reduce the amount and rate of the water runoff and thus reduce the amount of erosion) $$\large{dimensionless}$$ $$\large{ K }$$ = soil erodibility factor (units of soil loss per unit of soil erosivity) $$\large{dimensionless}$$ 