A spatial study of mangrove ecosystems for abrasion prevention using remote sensing technology in the coastal area of Pandeglang Regency

The coastal area of Pandeglang regency, which faces the Sunda Strait, is prone to natural disasters. Wave height and tides, including tsunami, are disasters that frequently hit the area. The mangrove ecosystem plays an importance role in reducing the abrasion that mostly caused by waves. In addition to preventing abrasion, the mangrove root system can hold sediment. So that it will expand the coastline or accretion. This study aims to determine the effect of the existence of mangrove ecosystems on changes in coastline, especially the occurrence of abrasion during 2010 to 2020. The research method uses remote sensing. Data collection uses Landsat 7 ETM+ in 2010, Landsat 8 OLI/TRS in 2015 and 2020. As a results, the mangrove ecosystem area along the coast of Pandeglang Regency had expanded from 1,632 ha in 2010 to 1728.06 ha in 2015 and decreased to 1,443.19 ha in 2020 due to the 2018 tsunami. Of course, it also affects the occurrence of abrasion, from 2010 to 2015 the abrasion occurrence affected 371.94 ha of coastline and decreased to 273.52 ha until 2020. Spatially, the largest post-tsunami abrasion occurred in the mangrove area of Cimanggu Sub-district, with about 28% of the mangrove area being reduced.