Struktur Komunitas Larva Nekton dan Kaitannya dengan Siklus Pasang Surut pada Estuari Belawan Provinsi Sumatera Utara

Abstract

The research was located in the Belawan Estuary located in Medan City, North Sumatra Province regarding the Tidal Relationship to Nekton Larvae. The research was conducted in October – December 2023 and used 8 station points. Belawan Estuary is an estuary that functions as a spawning area, nurturing area and foraging area for various types of fish. Nekton larvae sampling was carried out by purposive sampling where eight station points had been selected. Samples of nekton larvae were taken using a net larva tool. The results of this study showed the total number of nekton larvae spatially and temporally at high tide and low tide, namely 13 families and 13 genera consisting of 2,631 individuals of nekton larvae. The highest abundance value was spatially obtained at high tide at station II with a value of 8,336 and the lowest at low tide at station VII with a value of 56. While the highest abundance value temporally is obtained at high tide in the Full Moon phase with a value of 11152 and the lowest at low tide in the New Moon phase with a value of 336. With the value of diversity index (H') obtained spatially and temporally at high tide and low tide values of 0.007 – 1.52 is included in the low to medium category. Tidal relationships in front of larval abundance and diversity are related at high tide and low tide. Because at high tide and low tide there are differences in currents and tidal strength of sea water that carries fish larvae in and out of the river mouth. The relationship of water quality parameters to the abundance and diversity of nekton larvae using PCA Analysis (Principal Component Analysis).