ESTIMATING THE RESPONSE OF MANGROVE ECOSYSTEMS IN HIGHLY PROTECTED BAY ENVIRONMENTS IN URBAN AREAS TO SEA LEVEL RISE: CASE FROM INNER AMBON BAY, AMBON ISLAND, INDONESIA

Inner Ambon Bay (IAB) is a small bay with an elongated shape, with a maximum length of about 5.1km and a maximum width of about 2.6km, and is located within the administrative area of Ambon City, the capital of Maluku Province. The waters of the bay are highly protected. There is a fairly extensive mangrove ecosystem on the northeast side of this bay which is used for various purposes, including educational and research activities. The increase in the population of Ambon City has caused residential areas to develop by expanding the mangrove area from the land side. Meanwhile, it is estimated that by 2100, the sea level will rise to a height of around 1.1m above the current sea level. Because of its benefits and to maintain the natural conditions of IAB, the existence of mangroves in the bay needs to be maintained. It is essential to examine the future of the mangrove ecosystem concerning sea level rise (SLR) to determine effective methods for preserving its presence in the bay. This study examines the possibilities in the mangrove ecosystem if the sea level rises to 1.1m above the present sea level. The results of this study show that the opportunity for mangroves in IAB to adapt to SLR is through recruitment in the population by mangrove species that are tolerant of SLR (Rhizophora). The opportunity can be increased by preventing residential areas from expanding into mangrove areas and by building permeable dams to encourage mud deposition and artificial shelter for propagule to help natural colonization.