TYPES AND ABUNDANCE OF PHYTOPLANKTON AROUND THE FLOATING CAGE FISH CULTURE IN THE KOTO PANJANG DAM, XIII KOTO KAMPAR SUB-REGENCY, KAMPAR REGENCY RIAU

Abstract

Waters around the fish cage culture is rich with organic materials and it is a sufficient habitat for phytoplankton. To understand the types and abundance of phytoplankton around the floating cage area in the Koto Panjang dam, a study was conducted on May – June 2012. There were 3 stations, in the Tanjung Alai (St 1), Batu Bersurat (St 2) and Pulau Gadang Baru (St 3). In each station there were 2 sampling sites, close to the cage and 5 meters from the cage. Samplings were conducted 3 times, once/ week. Phytoplankton was identified based on Sachlan (1980), Davis (1995) and Yun Fang (1995). Results shown that the highest abundance of phytoplankton present in the St 1 (5,360 cells/ ml, 18 species), followed by St 2 (4,162 cells/ ml, 16 species) and St 3 (2,559 cells/ ml, 15 species). Types of phytoplankton around the fish cage culture in general are as follow: Bacillariophyceae (8 species), Cholorophyceae (12 species), Cyanophyceae (7 species) and Xanthophyceae (2 species). The diversity of phytoplankton in the study area are medium (H was 1.74 to 2.06), and there was no dominant species (C was 0.25-0.36). Nitrat concentration in the study area was relatively high, 0.62-1.03 mg/l, and phosphate concentration was 0.03-0.10 mg/l. Based on data obtained, it is concluded that the abundance of phytoplankton in the floating cage area is relatively low.