Sebaran Spasial Bentos pada Ekosistem Mangrove di Estuari Belawan Provinsi Sumatera Utara

Abstract

An estuary is a form of Bay on a partially closed Coast, where fresh and sea water meet and mix. The Belawan estuary is one of the coastal areas of the east coast of Sumatra that has an ecosystem with mangrove potential according to the North Sumatra Forestry Service (2011), its current area is 158,637.2 hectares. It is suspected that the Belawan mangrove ecosystem area is now also starting to experience degradation due to land conversion activities. The spatial distribution of benthos can be described through diversity, abundance and distribution maps.The purpose of this study is to structure the bentos community, the spatial distribution of bentos community and the relationship of mangrove density with bentos density in the mangrove ecosystem in Belawan Estuary, North Sumatra province. This research has been carried out from September to November 2023. The research method used is purposive sampling method. The results obtained as a whole 3209 individuals consisting of 2 phyla, 3 classes, 17 families and 40 species of benthos. The highest density value is at Station 1 which is 104 ind/m2 and the lowest density is at Station 21 which is 16.6 ind/m2. the highest diversity index value is spatially located at Station 28 is 2.41 with medium category and the lowest diversity index value is spatially located at Station 15 and 16 is 0. The highest uniformity index value is at Station 15 which is 1.82 with high category and for the lowest is at Station 0.02 with low category while the dominance index value obtained at Station 5 is 0 which indicates the lowest dominance index, at Station 10 which is 0.36 which indicates the highest dominance index. The registered bentos community is unevenly distributed at 28 Station points.