ABUNDANCE AND DISTRIBUTION OF ZOOPLANKTON IN THE MUSI RIVER DOWNSTREAM WATERS OF SOUTH SUMATRA

Abstract

Zooplankton is an organism that has an essential role in the food chain in the waters. Zooplankton serves as a secondary producer and can be used as an indicator of the quality of the waters. The existence of zooplankton is closely related to the aquatic environment's physical, chemical and biological parameters. This study aimed to identify the types of zooplankton and determine the abundance and distribution of zooplankton in the lower Musi River, South Sumatra. This research was conducted in September 2021. A zooplankton sampling used a plankton net with a mesh size of 30 m and a plankton net mouth diameter of 30 cm at 2 meters below the water surface. The study found 3 large groups of zooplankton, namely the phylum of Crustacea (Nauplius, Copepoda, Branchiopoda, Shrimp Larvae, Calanus, Diaptomus, Oithona), Annelida (Polychaeta) and fish larvae. Zooplankton abundance ranged from 708-23708 ind/m³, with a moderate diversity index value, high similarity, and none dominates.

Keywords: Abundance, distribution, Musi River, zooplankton.