intercropping with a wide diversity of different plant species will enable the build up of a wider range of soil microorganisms which will accelerate the restoration of a more fertile soil, and of course help to bind the soil to prevent erosion.
In case of slope land I would consider intercropping with combination of annual and perennial crops (with perennial ground cover) in critical points in order to prevent soil erosion and allow soil restoration.
Intercropping with different crops will reduce the erodibility of soils and the impact of the torrential rains on soils because of the increased root biomass holding the soils together. besides,this will reduce the effect of slope factor in determining Universal Soil Loss Equation .The shade provided by the crops will stimulate activities of earthworms and other soil microbes which will improve soil fertility and general soil health for sustainable food production