SINMAP · agroforestry treatment

Stability Index Mapping (SINMAP) Calculator for Agroforestry Treatment

Can tree planting increase slope stability?

This calculator evaluates slope stability using the SINMAP algorithm (see the SINMAP manual), which includes a root cohesion parameter Cr (N/m²). Cr can be changed according to the chosen plant species, and the calculator returns the Stability Index (SI).

SI ranking

SI > 1.5Stable slope zone

1.5 – 1.25Moderately stable zone

1.25 – 1.0Quasi-stable zone

1.0 – 0.5Lower threshold zone

0.5 – 0.0Upper threshold zone

< 0.0Defended slope zone

Stability Index 1.69

Treatment efficiency comparing to the bare slope (Cr = 0) +0.0%

Stable slope zone

Root cohesion

Root cohesion, Cr 0 N/m²

Hillslope and soil parameters

Slope angle, θ 30 deg

Soil thickness, h 0.6 m

Wetness (saturation), W 0.50

Soil cohesion, Cs 5000 N/m²

Friction angle, φ 30 deg

Density ratio, r 0.50

Default parameters for the hillslope and soil properties in this calculator were taken, as an example, from the SINMAP modeling conducted for the Nuru International Ethiopia project.