Types and Abundance of Phytoplankton in the Tajwid Lake, Langgam Sub-District, Pelalawan District, Riau Province

Abstract

Tajwid Lake is an oxbow lake that receives water from the Kampar River during rainy season. To understand the types and abundance of phytoplankton present in that lake, a study has been conducted in Ferbruary 2016. There were 3 stations, Station 1 is in the inlet, Station 2 is in the middle of the lake and Station 3. Vertical sampling sites were decided base on the transparency of the water namely at surface water, in the middle of lake, and in the bottom of lake. Samplings were conducted 3 times, once/ week. Results shown that there are 36 species of phytoplankton present in the lake. They were classified into four classes, namely: Bacillariophyceae (8 species), Chloropyhceae (17 species), Cyanophyceae (8 species) and Euglenophyceae (3 species). The average of phytoplankton abundance was around 723 – 4,485 cells/L, species diversity index (H\u27) was 4.76 – 5.01, uniformity index (E) was 0.71 – 0.86 and dominance index (C) was 0.034 – 0.044. While the water quality parameters were as follows: temperature 28 – 300C, transparency 51.3 – 69 cm, depth 6.3 – 12.3 m, pH 5, CO2 4.7 – 13.9 mg/L, DO 2.3 – 8.3 mg/L, nitrate 0.02 – 0.11 mg/L and phosphate 0,02 – 0.1 mg/L. Based on the abundance of pyhtoplankton, it can be concluded that the Tajwid Lake water can be categorized as oligotrophic