AN EXPLORATIVE ANALYSIS OF LAND USE LAND COVER CHANGES AND HYDROMETEOROLOGY OF THE VAIGAI RIVER BASIN, INDIA

The impact of land use and land cover changes (LULCC) is one of the major contributors to increasing greenhouse gas emissions to the atmosphere. At the terrestrial surface, the impact of LULCC is realized in altered hydrology. Conversion of cultivable lands into fallow lands severely affects crop production in agriculturally dominant basins such as the Vaigai River Basin (VRB) in Tamil Nadu, India. Considered as a granary of South Tamil Nadu, any LULCC in VRB results in uncertainty in food production. Therefore, in this study, Landsat images were used to evaluate changes in land use and MODIS NDVI images to estimate changes in browning and greening in VRB during 2001-2020. We also analyzed the rainfall and river discharge in the basin to understand the variations from 2001 to 2019 concerning LULCC. The results showed an increase of seventy-seven percent in fallow lands between 2010 and 2020 and a forty-one to fifty-nine percent increase in urban settlements between 2001 and 2020 in the basin. The impacts of LULCC were realized in monsoon rainfall with no change in river discharge in the lower Vaigai Basin. The study results will aid regulated land use planning and encourage further research on feedback between terrestrial and atmospheric water fluxes for ensuring food security.