干旱区生态环境知识资源中心

A distributed parameter sediment delivery model is linked with 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 watershed scale. The heterogeneous and complex land surface within the watershed divided into grid cells of 30 x 30 m. Data on vegetative cover are derived from the digital analysis of Landsat Thematic Mapper. Spatial sediment delivery in an arid drainage basin in Argentina is analysed through preprocessing by GIS, calculation of sediment delivery, and post processing and display of spatial output in the GIS. The model accurately predicts, even for the same values of flow shear stress, the higher sediment delivery from bare surfaces as compared to surfaces protected by vegetative cover. This study enables the identification of vulnerable regions within a watershed, thus facilitates improvement in planning of soil conservation systems.