Modelling Topographic Potential for Erosion and Deposition Using GIS

Modeling of erosion and deposition in complex terrain within a geographic information system (GIS) requires a high resolution digital elevation model (DEM), reliable estimation of topographic parameters, and formulation of erosion models adequate for digital representation of spatially distributed parameters. Regularized spline with tension was integrated within a GIS for computation of DEMs and topographic parameters from digitized contours or other point elevation data. For construction of ow lines and computation of upslope contributing areas an algorithm based on vector-grid approach was developed. The spatial distribution of areas with topographic potential for erosion or deposition was then modeled using the approach based on the unit stream power and directional derivatives of surface representing the sediment transport capacity. Presented methods are illustrated on study areas in central Illinois and the Yakima Ridge, Washington.