Mapping and dynamic analysis of mangrove forest during 2009–2019 using landsat–5 and sentinel–2 satellite data along Odisha Coast

Abstract

Mangrove forests in India are situated along the tidal sea edge of the Arabian Sea and Bay of Bengal which is under threat from both natural and human-induced land-use changes. The multi-temporal satellite data and image processing techniques are usually employed to monitor changes in vegetation dynamics. In this study, the decadal changes of mangrove forests were accomplished along the Odisha coast, India using the Landsat–5 and Sentinel–2A satellite data for 2009 and 2019, respectively. The satellite data were obtained and processed in the Google Earth Engine (GEE) platform. This study aims to derive the spatial extent of mangrove using the high-resolution satellite data and support vector machine (SVM) classifier. The result reveals that the total mangrove extent increased from 222.43 km2 (2009) to 252.47 km2 (2019) which indicates an increase in area by 30.04 km2 (or 13.5%) during the last one decade. The highest increase in mangrove area was in Hatamudia Reserve Forest (15.54 km2) and coastal belt of Bhadrak (9.46 km2) followed by Bhitarkanika National Park in Kendrapara (3.05 km2), Baranaula and Akumi River estuary in Jagatsinghpur (1.12 km2), and Subarnarekha River intertidal zone in Baleshwar (0.87 km2). A significant increase in mangrove forests occurred due to plantation, awareness, restoration, and coastal zone management plan. This study demonstrates the potential of high-resolution satellite data to produce an accurate map in monitoring changes in mangrove forests at a decadal time-scale by using the GEE platform which can help in planning conservation strategies and priorities.