Abstract:
The research was conducted from November to December 2012 at the Singkarak Lake, West Sumatera Province and aims to understand the vertical distribution of zooplankton. Method used in this research was a survey method. Zooplankton samples were collected from 4 stations. They were taken using a water sampler and then sieved by a plankton net no. 25.
Results shown that there were 19 genera, consisted of Rotifers (5 genera), Euglenophyceae (3 genera), Ciliates (2 genera), Protozoa (1 genus), Copepods (1 genus), Cladocera (1 genus), Sarcodina (2 genera), and Crustacean (4 genera). In the surface, the zooplankton abundance was ranged from 163 – 347 organisms/l, with H’ was 1.741 to 2.371, C was 0.221 – 0.302, E was 0.465 – 0,750. In the 100 cm depth, the zooplankton abundance was ranged from 1.741 to 2.371 organisms/l, with H’ was 2.702 – 3.006, C was 0.137 – 0.188, E was 0.660 – 0.864. In the 200 cm depth, the zooplankton abundance was ranged from 377 – 823 organisms/l, with H’ was 2.509 – 3.272, C was 0.113 – 0.209, E was 0.682 – 1.026. Water quality parameters in general were as follow : temperature 28.3 to 29.5 °C, brightness 70.4 to 224.6 cm, depth 3 to 4 m, TSS : 10.7 to 13.4 mg/l, DO : 2.5 to 3.6 mg/l, CO2 : 7.2 to 9.9 mg/l, and pH was 6.
