Use of Remote Sensing and GIS Techniques in Identification of Landslide Vulnerable Zones of Shastri River Basin Along the West Coast of Ratnagiri District, Maharashtra

The atmosphere, hydrosphere, and lithosphere are subjected to different processes, leading to natural hazards like weathering, erosion, floods, cyclones, landslides, earthquakes, tectonic movements, etc. Environmental degradation is a serious aspect of the recent past, mainly due to natural and manmade interactions. The pressure for infrastructure development due to rapid urbanization has led to the expansion of construction activities. It has catapulted the frequency of landslides to dramatic proportions in recent decades, especially along western ghats. The West Coast of India (WCI) has attracted the attention of Geo-scientists due to its neo-tectonic setup, continuing seismic activities, sea-level changes, and also due to environmental degradation. It is followed that very limited attempts have been made related to the land sliding along the west coast tract of Maharashtra. The present investigations are emphasized mainly to locate the landslide vulnerable zones of Shastri River Basin (SRB), Ratnagiri district of Maharashtra by using remote sensing data, GIS techniques along field studies. The area lies within a triple junction of Koyana-Kurduwadi Lineament (KKL), West Coast Fault (WCF), and Panvel Flexure (PF). Based on the integration of data from various thematic maps viz. lithology, lineaments, slope, geomorphology, land use-land cover along with inventory map, Landslide Vulnerable Map (LVM) of the SRB has been prepared. It follows that about 29% area of the SRB forms a highly vulnerable zone for land sliding. These zones are mainly confined to steep slopes, wasteland, highly weathered basalts, and deep valleys and in the vicinity of lineaments.