A distributed spatial sediment delivery model for the arid regions

A distributed parameter sediment delivery (sediment yield differentiated with respect to time and drainage basin area) model has been derived from basic/principles and linked with a personal computer-based, low cost, geographic information system (GIS) to facilitate preparation, examination and analysis of spatially distributed input parameters as well as to link the sediment delivery from a micro-scale to the drainage basin-scale. The heterogeneous and complex land surface within the drainage basin has been divided into sub-areas. Data on vegetative cover have been derived from the digital analyses of satellite images. Spatial sediment delivery in arid drainage basins in Argentina and India has been analyzed through preprocessing employing GIS, calculation of sediment delivery, and post processing and display of spatial output in the GIS. The model accurately predicts, even for the same value of flow shear stress, the higher sediment delivery from bare land surfaces as compared to the land surfaces protected by the vegetative cover. The study further enables the identification of vulnerable regions (hot spots) within a drainage basin, thus facilitating improvements in planning of soil conservation systems.