Soil Erosion Explorer
Calculate soil erosion rates using the Universal Soil Loss Equation (USLE). Adjust rainfall intensity, soil texture, slope geometry, and land cover to estimate annual soil loss. Compare erosion across land uses and evaluate the effectiveness of conservation practices like terracing, contour farming, and cover crops.
Hillslope Cross-Section
Controls
USLE Results
Erosion vs Slope Steepness
Reference Guide
Universal Soil Loss Equation
The USLE predicts long-term average annual soil loss from sheet and rill erosion. Developed by Wischmeier and Smith (1978).
Where is the estimated soil loss in tons/hectare/year, and each factor captures a different driver of erosion.
R, K, and LS Factors
R (Rainfall Erosivity) measures the erosive force of rainfall. Higher rainfall with greater intensity produces more erosion. Approximated as .
K (Soil Erodibility) reflects how easily soil particles detach. Silty soils (K up to 0.7) erode far more than sandy soils. Organic matter reduces erodibility.
LS (Slope Length-Steepness) captures the topographic effect. Steeper, longer slopes accelerate runoff and increase erosion exponentially.
Cover Factor (C)
The C factor measures the protective effect of vegetation and ground cover on erosion. It ranges from 0 to 1.
| Land Cover | C Factor |
|---|---|
| Bare Soil | 1.000 |
| Cropland (conventional) | 0.350 |
| Grassland / Pasture | 0.010 |
| Urban / Paved | 0.010 |
| Forest | 0.003 |
Dense vegetation intercepts raindrops, slows runoff, and holds soil with root systems. Forests reduce erosion by over 99% compared to bare soil.
Conservation Practice Factor (P)
The P factor reflects the effect of support practices that reduce erosion. A value of 1.0 means no conservation; lower values indicate greater protection.
| Practice | P Factor |
|---|---|
| None | 1.00 |
| Contour Farming | 0.50 |
| Buffer Strips | 0.35 |
| No-Till Farming | 0.25 |
| Cover Crops | 0.25 |
| Terracing | 0.10 |
When multiple practices are combined, their P factors multiply together. For example, contour farming (0.50) with terracing (0.10) gives P = 0.05, a 95% reduction.
