IMPACT OF VEGETATION ON SLOPE STABILITY IN A HUMID TROPICAL ENVIRONMENT - A MODELING APPROACH

Vegetation covers can provide a low cost, aesthetically acceptable solution to problems of erosion and slope instability, and are of greatest relevance in humid tropical areas, However, the impact of vegetation on slope stability is not fully understood, and may be detrimental in some cases, depending on the slope size and soil properties, There is therefore a need for quantitative methods of assessing the effect which vegetation will have on slope stability in order that appropriate design procedures can be developed, This paper describes a physically based distributed model which has been developed for this purpose, The model accounts for the dynamic mechanical and hydrological response of a vegetated slope to rainstorms, It has been applied to a range of slope conditions to develop guidelines on optimum vegetation cover type and configuration, and to estimate the risk and benefit of carrying out a range of bioengineering schemes. It is envisaged that the scheme will be of use to engineers designing remedial bioengineering solutions to offset shallow, infiltration-induced landslides in the tropics.