Kelimpahan dan Pola Distribusi Kerang Kapak (Pinna Bicolor) pada Ekosistem Lamun di Perairan Pulau Poncan Gadang Kota Sibolga Provinsi Sumatera Utara

Abstract

The seagrass ecosystem located in the waters of Pulau Poncan Gadang is known to have abundant biological resources, one of which is bivalves. One of the bivalve organisms found living in the waters of Pulau Poncan Gadang is the common razor clam (Pinna bicolor). common razor clam is one kind of shellfish that has a triangular shell shape, thin, tapering to the substrate and generally one of the large bivalves (30-40 cm) where those biota plays a role in the ecosystem as a water bioindicator. The aim of this research was to determined the abundance and distribution pattern of common razor clam (Pinna bicolor) in the waters of Pulau Poncan Gadang. This research was conducted in the waters of Pulau Poncan Gadang, Pasar Belakang Urban Village, Sibolga Kota District, Sibolga City in September 2021. Sampling of common razor clam was carried out using the quadratic transect method with 3 research stations and then the abundance and distribution pattern of the common razor clam were calculated. The results of this research on the abundance of common razor clam showed that the abundance grades ranges from 1.3 to 2.33 individuals/m2. Based on the observations obtained, the distribution index value of common razor clam (Pinna bicolor) from the three stations is known to ranges from 1.14 to 2.18, which classified as grouping distribution pattern.