Detection of shoreline changes using GIS and DSAS technique: Case of Kuchchaveli DS Division, the East coast of Sri Lanka

Abstract

Coastal erosion is affecting a large number of coastal areas.The coastal zone consists of immense geological, geomorphological, and ecological interests. The shoreline change has its impact, but it is mostly invisible. There should be a long and continuous set of data to observe the effects of shoreline change. This study aims to detect and analyse the shoreline changes along the Kuchchaveli DS Division coast between 1991 and 2021 using geographic information systems (GIS) and Digital Shoreline Analysis System (DSAS). Landsat imageries were geometrically and radiometrically corrected for the quantitative coastline delineation analysis. DSAS was used as a reliable statistical approach for the rate of coastline change. The shoreline change rate was demarcated based on End Point Rate (EPR) and Linear Regression Rate of change (LRR). The findings of the study indicate remarkable shoreline changes (1.151m/yr withdrawal and -0.800 m/yr erosion) in some parts of the research area between 1991 and 2021. Even though a large part of the study area show accretion, eroding shorelines are observed in the cost of GN divisions: Thiriyai GN, Senthur GN, Jayanagar GN, Cassim Nagar GN, Kuchchaveli GN, Kumpurupiddi North GN, Velor GN, and Iqbalnagar GN. This research gives a synoptic outlook of the potential threat to the shoreline of the Kuchchaveli DS division, allowing for the adoption of appropriate measures to prioritise the management of the coast.