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

Analysis Mode

Presets

Annual Rainfall800 mm

Soil Texture (must sum to 100%)

Sand30%

Silt40%

Clay30%

Organic Matter2.0%

Slope Length75 m

Slope Steepness9.0 %

Land Cover

Sediment Delivery Ratio30%

USLE Results

A = R \times K \times LS \times C \times P = 512.81 \text{ t/ha/yr}

R Factor

2279.93

K Factor

0.350

LS Factor

1.83

C Factor

0.350

P Factor

1.000

Sediment Yield

153.84

Erosion Risk Level

Severe

512.81 t/ha/yr

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).

A = R \times K \times LS \times C \times P

Where $A$ 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 $R \approx 0.0483 \times P^{1.61}$ .

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.