Electronic Theses and Dissertation

Gastropoda berperan penting sebagai bioindikator kualitas perairan karena
keanekaragaman, kelimpahan, serta sensitivitasnya terhadap perubahan lingkungan.
Penelitian ini bertujuan untuk mengidentifikasi jenis-jenis Gastropoda serta
menganalisis keanekaragaman, kelimpahan, dominansi, dan pola sebarannya di pantai
Tapak Gajah, Gampong Ie Meulee, Kota Sabang. Penelitian dilaksanakan pada
September–Oktober 2025 menggunakan metode purposive sampling. Pengambilan
sampel dilakukan dengan transek kuadrat 1×1 m pada tiga stasiun, disertai pengukuran
parameter fisika-kimia perairan. Identifikasi Gastropoda dilakukan di Laboratorium
Biologi Laut Fakultas Kelautan dan Perikanan Universitas Syiah Kuala. Hasil
penelitian menunjukkan bahwa terdapat 68 individu Gastropoda yang tergolong dalam
lima famili, dengan Engina mendicaria sebagai spesies paling berlimpah. Stasiun I
memiliki kondisi terbaik dengan kepadatan 8,7 ind/m², indeks keanekaragaman (H')
1,40, dan keseragaman (E) 0,60, mengindikasikan komunitas yang cukup stabil.
Sebaliknya, Stasiun III memiliki kepadatan serta nilai keanekaragaman dan
keseragaman terendah, diduga dipengaruhi aktivitas manusia. Dominansi tertinggi (D
= 0,78) terdapat di Stasiun II, menunjukkan adanya spesies yang mendominasi. Pola
sebaran Gastropoda cenderung mengelompok sesuai kesesuaian habitat. Parameter
fisika-kimia perairan berada pada kisaran ideal untuk mendukung keberadaan
Gastropoda.

Gastropods play an important role as bioindicators of water quality due to their diversity, abundance, and sensitivity to environmental changes. This study aimed to identify gastropod species and analyze their diversity, abundance, dominance, and distribution patterns at Tapak Gajah Beach, Gampong Ie Meulee, Sabang City. The research was conducted from September to October 2025 using a purposive sampling method. Samples were collected using 1×1 m quadrat transects at three stations, accompanied by measurements of physicochemical water parameters. Gastropod identification was carried out at the Marine Biology Laboratory, Faculty of Marine and Fisheries, Universitas Syiah Kuala. The results showed a total of 68 gastropod individuals belonging to five families, with Engina mendicaria being the most abundant species. Station I showed the best ecological condition, with a density of 8.7 ind/m², a diversity index (H') of 1.40, and an evenness index (E) of 0.60, indicating a relatively stable community. In contrast, Station III had the lowest density, diversity, and evenness values, likely influenced by human activities. The highest dominance (D = 0.78) occurred at Station II. Gastropod distribution tended to be aggregated according to habitat suitability. Physicochemical parameters remained within optimal ranges for gastropod survival.