Distribution Of Phytoplankton As Indicators Of Water Quality In The Terengganu Estuary, Malaysia

Abstract

River mouth is a part of an estuarine system and a boundary of end point of the river flows and a starting point of the ocean, where the dynamic inflows of fresh and salt water that provide high level of nutrients to support aquatic life systems including microscopic plant species such as phytoplankton. Pattern of water quality in estuaries is influenced by the river flow, wastewater discharged and the tidal phenomena for the study area. In order to identify the most dominant group of phytoplankton species and its distribution pattern as indicators of water quality, the Terengganu estuary, Malaysia has been chosen as a study area with an estimated 11.2 km reach

towards downstream. A comprehensive data collection has involved a total of ten sampling stations. A series of laboratory tests has been also carried out to identify the phytoplankton species and to analyst the density of the phytoplankton. The results of the analysis show that there are six types of phytoplankton were successfully identified, namely: Euglenophyta (Euglenoids), Bacillariophyta (Diatoms), Chlorophyta (Greenalgae), Cyanophyta (Blue - greenalgae), Pyrrophyta (Dinoflagellates) and Chrysophyta (Chrysophytes). Results have found out that most of the phytoplankton is more abundant in the southern part of the coastal area compared to the Northern part and estuary area with the 49 % of Diatoms and 42 % of blue - green algae respectively were successful identified as the most dominant of the phytoplankton in the Terengganu estuary. Canberra Metric method has been applied, which is much simplified in data analysis and interpreting process especially on the temporal variation of phytoplankton data. It also shows that diatoms, blue-green algae and Dinoflagellates likely to have strong relationship in occurrence of the TOC, Nitrate, Dsi and TDN. On the other hand green-algae, Chrysophytes and Euglenoids are strongly in relationships with the occurrence of the Nitrate, DSi, TSS and clorofil-a.