Exploring physical and human Induced coastal Morphodynamics: a study with reference to Nintavur to Addalaichenai coastal areas of Ampara District, Sri Lanka

Abstract

Observing and mapping the long-term coastal morphodynamics because of the human and physical induced factors using conventional methods could not give expected outcomes. State-of-the-art technology and tools are the best methods to do so. Thus, this study is to explore the long-term coastal morphodynamics of the coastal strip from Nintavur to the Addalaichenai area using the Landsat satellite images of the years 1991, 2001, 2011 and 2019, downloaded from the Earth Explorer website. Google Earth (GE) historical images were also used for the comparison of periodic coastal morphodynamics. Normalized Difference Water Index (NDWI) was processed for land and water separation. Direct observation, the perspective of the respective officials and inhabitants, and reports concerning the departments and authorities were also considered as the sources for this study. In conclusion, this study has found that the coastal morphological changes have been made because of both human and physical induced factors of which waves and river flooding within the study area are the physical factors and construction activities; port and breakwaters are the human activities which have modified the beach in the study area. In comparison, after the construction of the port, remarkable coastal morphodynamics has been recorded in the period from 2011 to 2019 in the study area.