Keanekaragaman Bentik Alga dan Hubungannya dengan Kualitas Air di Perairan Sungai Batang Toru Kabupaten Tapanuli Selatan

Abstract

Batang Toru River is one of the largest river in South Tapanuli with length 69,32 Km. Benthic algae is one of the aquatic organisms thet live in it. Diversity of benthic algae research has been carried out in August 2013. Study aimed to determine the diversity of benthic algae and relationship to physical and chemical factors in Batang Toru river waters. The method used was purposive random sampling where sampling station consisted of three observation station. Based on the research result obtained by benthic algae genus consist of 63 family 31, and 4 classes. The highest density of benthic algae was found in the genus Gomphonema ind/m2 498.77 (Station 1) and the lowest in the genus Coloneis, Dimorphococcus, Coelastraum, Netrium, Chrooccus, (Station 2) and Rhopalopodia Opephora, mesotaenium (Station 3), each for 1,23 Ind/m2. Diversity index was highest at station 3 at 3,17 and lowest at station 3 by 2,86. Uniformity index was highest at station 1 was 0,84 and the lowest 0,75 station 3. The results or correlation analysis showed that temperature, pH, flow rate, Dissolved Oxygen, Biological Oxygen Diamend, nitrate and phosphate levels have a very strong correlation to the diversity of benthic algae.