Kepadatan jenis dan hubungan panjang bobot landak laut (Echinoidea) pada ekosistem lamun di Perairan Teluk Tomini Kabupaten Pohuwato Gorontalo

Abstract

: Sea urchins (Echinoidea) are invertebrate animals belonging to the phylum Echinodermata that can be found in seagrass ecosystems. This study aims to determine the species and density of sea urchins, as well as the relationship between their length and weight in seagrass ecosystems in the waters of Teluk Tomini, Pohuwato Regency, Gorontalo. The method used in this study is random sampling, where research stations are determined based on the presence of seagrass. Data collection was carried out in January 2022 at two locations, namely the villages of Bumbulan and Libuo, Paguat District, Pohuwato Regency, using a 4 × 25 m square transect method placed perpendicular to the coastline towards the sea. From this study, three (3) species were found, namely Diadema setosum, Diadema savignyi, and Echi-nothrix calamaris, with varying density values. The analysis showed that D. setosum is the species with the highest density value in both locations, namely 0.016 ind/m2 (Bumbulan) and 0.09 (Libuo). Furthermore, D. savignyi species with a density of 0.03 and 0.05 ind/m2, while E. calamaris was only found in Bumbulan with a density value of 0.02 ind/m2. The analysis of body length and weight showed a negative relationship for all species.