SPATIO-TEMPORAL ANALYSIS OF UPPER TUNGABHADRA SUB BASIN, KARNATAKA, INDIASanthosh Kumar T.M and K.L. Prakash
An attempt has been made with an aim to document the land use and land cover changes in treated and untreated catchments in the Tungabhadra sub basin using geospatial data of the last three decades representing 1996, 2006 and 2016. The satellite data obtained from Landsat thematic mapper were used for land use and land cover classification. The data sets were processed for False Color Composite by using ERDAS Imagine 9.3. Three decadal analysis results revealed that barren land is increased to 4.89% and waste land to 37.12%. Alarmingly, the built up area is increased from 143.83 Sq.km (1996) to 583.34 Sq.km (2016). Statistics reveal that, larger area of the catchment was treated with various engineering and biological measures by the authorities (26,350 Sq.km) and whereas a smaller portion of 2766.60 Sq.km is untreated. As it is an irrigated area, the more treatment activities need to be covered by the Watershed Development Department. Land cover analysis revealed that, there is no significant exponential change observed in untreated catchment compared to treated catchment. Hence, due to ineffectiveness or failure of treatment activities in the treated catchments leads to serious ramification on siltation of Tungabhadra reservoir. Thus, water storage capacity has reduced and the purpose of reservoir for which it was built could not be fulfilled.