MAPPING LAND-USE PATTERNS IN A RIVER CATCHMENT USING GEOGRAPHICAL INFORMATION-SYSTEMS

The paper describes a methodology developed to compile land use maps u sing multiple data sources integrated using geographical information s ystems (GIS). A river basin is the base unit for the study, being a co mplete hydrological and topographical unit. The methodology developed has real applications in river basin modelling. Multi-temporal satelli te imagery, from different agricultural seasons, was used to produce l and-cover maps for the catchment, using knowledge-based re-classificat ion. The drainage network, elevation and other topographic and themati c data were digitized from maps. The GIS was used to integrate these d ata sources and provide tools for manipulation of the data. This proce dure enabled spectrally inseparable classes to be delineated and land use maps to be prepared. Various land use classes, including wasteland s, and appropriate preventive measures, have been developed. The paper also envisages some future studies for catchment management policies.