The diversity and abundance of phytoplanton during a tidal cycle at jeti Tanjung Kuala, Tumpat, Kelantan

Abstract

Diversity and abundance of phytoplankton at Tanjung Kuala waterway was examined during a tidal cycle in September 2007. Water sample (42L) was collected every hour within 24 hours, and filtered through 20 μm mesh size plankton net. Filtered water sample was concentrated to 200rnL and preserved with Lugol's solution. The preserved water sample was concentrated to 1 OmL subsamples and kept in glass bottles in the laboratory. Identification of phytoplankton to the genus level and cell counting using Lackeys Drop method was done under light microscope. Calculation was done for density (cell.L- 1), diversity index and evenness index. From the results, 80 genera were found within 24 hour observation. During high tide 71 genera were found, and 67 genera were found during low tide. Average diversity index during high tide at 3.8565, and low tide at 3.8397. Average evenness index during high tide was 0.8019, while low tide was 0.7972. Density of phytoplankton during high tide was recorded at 2206 cell.L-1, whereas the average density during low tide was 2859 cell.L-1 • Bacillariophyta was a major division followed by Dinophyta, Cyanophyta, Cholorophyta and Euglenophyta. Chaetoceros and Rhizoso/enia, were found abundantly at the sampling site during high tide, while the Peridinium and Closterium increased the density of phytoplankton during low tide drastically. From statistical analysis, there was no correlation between salinity and diversity index of phytoplankton at the sampling site. No significant difference were found between diversity index and evenness index with tidal cycle and day or night