KAJIAN KEPADATAN DAN DISTRIBUSI UKURAN CANGKANG KERANG LOKAN (Batissa violacea)DI EKOSISTEM MANGROVE BATANG SIKABAU NAGARI AIR BANGIS KABUPATEN PASAMAN BARAT

Abstract

Kerang lokan ( Batissa violacea ) merupakan salah satu jenis kerang yang memiliki nilai ekonomis serta bernilai untuk dikembangkan sebagai sumber protein untuk memenuhi kebutuhan masyarakat. Penelitian bertujuan untuk mengkaji kepadatan populasi,hubungan panjang berat, distribusi ukuran cangkang kerang lokan di ekosistim hutan mangrove Batang Sikabau Nagari Air Bangis Kecamatan Sungai Beremas Kabupaten Pasaman Barat. Penelitian ini dilaksanakan pada bulan Maret - April 2017. Metode yang digunakan dalam penelitian ini menggunakan metode deskriptif. Rata-rata kepadatan kerang lokan antara 0,84 – 1,44 ind/m2. Hubungan panjang berat yang didapat bersifat isometrik yaitu pertambahan berat dan panjang seimbang. Distribusi ukuran cangkang kerang dengan panjang total cangkang 3,8 – 7,9 cm, menghasilkan 1 pengelompokan ukuran cangkang kerang lokan dengan nilai rata-rata 5,20 cm untuk kerangjantan dan 4,10 cm untuk kerang betina. Kata kunci : Kepadatan, Distribusi, Cangkang, Lokan, Air Bangis Abstract Batissa violacea is one kind of shell that has an economical valuable prince in society. It also has a high prinze to be developed as a protein’s resources to fulfill society’s requirement. The aim of this research was to investigate the density’s society, to correlate between height and weight, to distribute the seashell’s shell in mangrove’s forest ecosystem at Batang Sikabau Nagari Air Bangis Kecamatan Sungai Beremas Kabupaten Pasaman Barat. This research started from March untill April 2017. The method of this recearch was descriptive method. I concluded that the density of lokan were 0.84 - 1.44 ind / m2.The correlation between length and weight were included as isometric. It meant that the addition of the length and weight were balanced. The measurement’s distribution of lokan’s which had the shell’s total length were 3,8 - 7,9 cm.So, I concluded that they produced one category that have the most of lokan between 5,20 cm for the male shell and 4,10 cm for female’s shell. Keywords : Density, Distribution, Shell, Lokan, Air Bangis