Study on zooplankton diversity aquatic ecobiology of Batang Toru River, North Sumatera, Indonesia

Abstract

The Batang Toru River is a fairly long river, flowing from the North Tapanuli region and emptying into the Indian Ocean (South Tapanuli Regency). Increased deforestation in the Batang Toru River area has increased the potential for decreasing water quality of the Batang Toru River. The purpose of this study was to determine the condition of the water quality of the Batang Toru River. This research was conducted for 3 months (April, July, October), in the Batang Toru River and its surroundings (14 observation stations scattered from the area near the upstream to the coast). The data analysis used in this research is the analysis of the abundance and composition of the types of phytoplankton, the Diversity Index (H'), the Evennes Index (E), and the Dominance Index (C). Based on the research results, zooplankton in these waters consist of Six Phylum of zooplankton, such as Ciliophora (4 genera), Amoebozoa (2 genera), Cercozoa (1 genera), Rotifera (9 genera), Arthopoda (3 genera), and Annelida (2 genera). Diversity, Evenness, and Dominance Indices were around 0.349-1.847, 0.503-0.994 and 0.240-0.802. Based on the index value, it can be concluded that the Batang Toru River is classified as experiencing moderate ecological pressure.