KEANEKARAGAMAN KEPITING MANGROVE DI PANTAI MERDEKA DESA BAGAN KUALA KECAMATAN TANJUNG BERINGIN KABUPATEN SERDANG BEDAGAI

Abstract

The mangrove ecosystem in Merdeka Beach has an important ecological role as a habitat for biota, including mangrove crabs (Brachyura). This study aims to identify crab species, analyze diversity (H'), evenness (E), dominance (C), and determine physical-chemical environmental parameters and correlations of environmental factors with species in the area using descriptive observation methods with purposive sampling techniques at three observation stations. The results of the study found eight crab species, namely, Scylla tranquebarica, Tubuca dussumieri, Austruca triangularis, Austruca perplexa, Parasesarma pictum, Episesarma versicolor, Tubuca rosea, and Gelasimus tetragonon, with the highest number of species in Tubuca rosea and Parasesarma pictum. The structure of the crab community is relatively stable and even without any species that dominates extremely, where station II has the highest diversity while station III has the lowest due to the sparse mangrove density and high light intensity. Environmental factors such as pH, salinity, and DO generally strongly support crab habitat, supported by levels of the heavy metal lead (Pb) in the air and sediment, which remain well below government and USEPA quality standards. Therefore, it can be concluded that mangrove vegetation density and environmental parameters at Merdeka Beach are closely related in supporting crab habitat, creating an ecologically stable coastal ecosystem.