Impact assessment of check dam recharge sites in the pappiredipatti Watershed (South India) by using LULC and NDVI Data

Abstract

Agriculture is one of the essential sector in because of the changing phenomenon of weather condition which is further complicated by the interaction of the vegetation with the environment. Scarcity of rainfall causes physiognomic changes can be identified by satellite images through the use of vegetation indices and landuse and land cover changes. The vegetation indices are sensitive to the rate of plant growth as well as to the amount of growth. They are sensitive to change in vegetation affected by moisture stress. Hence, scarcity can be monitored more systematically through remote sensing techniques than the ground based methods of collection of information. The capabilities of Geospatial techniques have been used to demarcate effective sites for monitoring functional characteristics of water conservation structures in the pappiredipatti watershed. In this study, land use/land covers have been used to delineate the existing recharge sites for water conservation measures. Increase of groundwater resource is proposed in the watershed by constructing runoff storage structures like as check dam, percolation tank and gabion structures. The site effective water conservation structures is determined by considering spatially varying parameters land use/land cover and natural difference vegetation index (NDVI) information of the watershed. Geospatial technique has been used to store, analyse, integrate spatial and attribute information pertaining to functional characteristics of land use and land cover within buffering distance in the area of interest of watershed. For detailed changes around recharge area assessment an attempt was made over the watershed. Crop growth area was assessed in and around under forest, barren land and dense vegetation area using temporal normalised difference vegetation index (NDVI) on 1985, 2005 and 2015. They have compared with vegetation area regions, and crop wise area growing were identified. Based on the result obtained from the study area on vegetation cover, buffered around recharge area impact was assessed by NDVI. Decrease in barren land on 2005 by identifying the NDVI threshold over predominantly sparse vegetation growing regions, crop wise area was identified. Further, the water body was estimated from NDVI data of 2005 and 2015 which have been validated for the vegetation assessment. The result of Landsat data use study indicated decrease in dense vegetation area that has leading to wide spread drought condition in the some part of the watershed.