GIS-Based Soil Erosion Modeling for Assessing Land Suitability in the Urban Watershed of Tallo River, South Sulawesi, Indonesia

The principal aim of this paper is to utilize spatial-based soil erosion information to assess land suitability at a watershed level. The specific aim is three-fold: 1. to develop techniques based on a GIS in the parameterization of a soil erosion model, which is designed for use at a large scale assessment; 2. to assess and map the spatial distribution of average annual rate of soil losses in and 3. to employ such related concept as soil loss tolerance to determine land suitability at a watershed level. The results indicate that around 56.5% of the area experience annual soil loss of less than 1 ton/ha/year, while erosion rate of more than 25 ton/ha/year covers a total area of 8.9%. This study suggests that the outputs of this modeling procedure can be used for the identification of land management units based on degradation levels, as well as the most suitable land use to be practiced on individual land units on a sustainable basis.