Habitat characteristics of bicolor Pen Shell (Pinna bicolor) in seagrass ecosystems in Poncan Gadang Island, Sibolga City, Sumatera Utara

Abstract

Poncan Gadang Island has a complete coastal ecosystem, one of them is the seagrass ecosystem. One of the biotas that inhabit the seagrass ecosystem on this island is the Bicolor pen shell. This shellfish has an ecological function because of its role in the food chain in seagrass beds and has economic value. This study aims to determine the abundance of bicolor pen shells and their relationship with seagrass cover, water physical-chemical parameters. The sampling was conducted at the research location in July – September 2021, which was located on Poncan Gadang Island. This activity was carried out at 3 stations. The primary data taken were the abundance of Bicolor pen shell, seagrass, physic-chemical parameters of water and substrate. Sampling was carried out three times. The results showed that the abundance of bicolor pen shells ranged from 1.8 to 2.8 ind m-2. Station 1 has the lowest abundance and the highest is at station 3. The PCA results show that the abundance of shellfish is positively related to temperature, DO, salinity and C-organic, while percent cover of seagrass, pH, water transparency, depth, and current were negatively related to the abundance of these shellfish.