Electronic Theses and Dissertation

Kekayaan biota laut di perairan kota sabang sangat beranekaragam yang mendiami perairan tersebut.salah satu organisme atau biota yang diketahui mempunyai peran penting, baik secara ekologi maupun lingkungan adalah kelompok moluska dari kelas gastropoda dan bivalvia. tujuan dari penelitian adalah untuk menentukan struktur komunitas melalui pendekatan rumus kepadatan, pola sebaran, keanekaragaman, keseragaman, dan dominasi. penentuan lokasi menggunakan pupossive sampling, pengambilan sampel dilakukan dua tahap yaitu pengambilan parameter perairan dan pengambilan sampel gastropoda dan bivalvia. hasil penelitian pada tiga stasiun pengamatan di kawasan perairan sabang yang bertepatan di pantai anoi itam, dan perairan lhok weng, ditemukan 19 spesies gastropda yang terdiri atas 10 famili dan 2 spesies bivalvia yang terdiri dari 2 famili. kepadatan gastropoda tertinggi terdapat pada stasiun ii sebesar 8 ind/m2. pola sebaran 10 spesies mengelompok dan 9 spesies seragam. nilai keanekaragaman (h’) kriteria tinggi berkisar antara 1,14 – 1,40, nilai keseragaman (e) seimbang berkisar 0,63 – 0,81, nilai dominasi (c) berkisar antara 0,39 – 0,53. kepadatan bivalvia tertinggi terdapat pada stasiun ii sebesar 0,69 ind/m2. pola sebaran 2 spesies seragam. nilai keanekaragaman (h’) kategori rendah berkisar 0 - 0,09, nilai keseragaman (e) tidak seimbang berkisar antara 0 – 0,07, dan nilai dominasi (c) berkisar antara 0 – 0,95. struktur komunitas gastropoda dan bivalvia di perairan sabang berada dalam kondisi stabil karena tidak ada spesies yang paling mendominasi. kata kunci : bivalvia, gastropoda, keanekaragaman, kepadatan, struktur komunitas

The wealth of marine life in the waters of Sabang City is very diverse that inhabits these waters. One organism or biota that is known to have an important role, both ecologically and environmentally, is thegroup of oluska from class Gastropods and bivalves. The purpose of the study is to determine the structure of the community through the formula approach of density, distribution patterns, diversity, uniformity, and dominance. Determination of location using pupossive sampling, sampling is carried out in two stages, namely taking aquatic parameters and sampling Gastropoda and Bivalves. The results of research at three observation stations in the Sabang water area which coincided on the coast of Anoi Itam, and Lhok Weng waters, found 19 species of Gastropda consisting of 10 families and 2 species of Bivalves consisting of 2 families. The highest gastropod density is found at station II of 8 ind/m2. The distribution pattern of 10 species is clustered and 9 species are uniform. The diversity value (H') of high criteria ranges from 1.14 – 1.40, the uniformity value (E) is balanced ranging from 0.63 – 0.81, the dominance value (C) ranges from 0.39 – 0.53. The highest density of Bivalves is found at station II at 0.69 ind/m2. The distribution pattern of 2 species is uniform. The diversity value (H') of the low category ranges from 0 - 0.09, the uniformity value (E) is unbalanced ranges from 0 - 0.07, and the dominance value (C) ranges from 0 - 0.95. The structure of the Gastropoda and Bivalve Community in Sabang Waters is in stable condition because there is no species that dominates the most. Key words: bivalves, gastropods, diversity, density, community structure