KOMPOSISI FORAMINIFERA BENTIK BESAR PADA SEDIMEN MANGROVE

Abstract

Large benthic foraminifera are unicellular organisms that live at the surface of the sediments and have the ability to form shells of calcium carbonate (CaCO3). This research was conducted with the aim of describing and analyzing the composition of the large benthic foraminifera found in the coastal mangrove areas of Tasik Ria and Tongkeina. Sampling activities were carried out by taking sediment samples from mangrove areas Tasik Ria and Tongkeina. The large benthic foraminifera identified were 3,680 specimens. Foraminifera species and genera obtained were 28 species from 15 genera in the mangrove sediments of Tasik Ria Beach and 23 species from 11 genera in the mangrove sediments of Tongkeina Beach. The dominant foraminifera genera with a proportion of more than 5% at both study sites were Ammonia, Amphistegina, Calcarina, Elphidium and Neorotalia. Based on the type of shells, foraminifera with light shells were more commonly found in the mangrove area of Tasik Ria than in Tongkeina. In contrast, more sandy-shelled foraminifera were found in the mangrove area of Tongkeina than in Tasik Ria. Furthermore, the Diversity Index for large benthic foraminifera obtained at both locations was in the medium category with values indicating the diversity of foraminifera species obtained in the mangrove area of the Tasik Ria coast was higher than the foraminifera obtained in the mangrove area of the Tongkeina coast.

Keywords: Large Benthic Foraminifera, Mangrove Area, Tasik Ria Beach, Tongkeina Beach