No abstract

This study investigated the spatial variation of nitrogen (N)-based and phosphorus (P)-based nutrients together with water quality parameters (temperature, pH, dissolved oxygen, biological oxygen demand, chemical oxygen demand and total suspended solids) in the Dungun River basin, Terengganu. The Water Quality Index (WQI) of the river was applied according to the Malaysian Department of Environment (DOE-WQI) and classified based on the Malaysian National Water Quality Standard (NWQS). Results showed that the major source of nutrients and water quality deterioration in the basin was most likely due to the effluent discharged from the nearby palm oil factory. The overall WQI mean value obtained was 85.44%, which indicated that the Dungun River basin was in a clean condition and categorised into Class II based on the NWQS classification. The overall mean mass N:P ratio was 19.8:1 which indicated that the algal growth was generally controlled by the P-based nutrients. Based on this study, it is suggested continuous monitoring necessary to be carried out for proper management of this river basin.

This study was conducted to determine the concentration and possible sources of dissolved and particulate heavy metals in Lake Kenyir, Terengganu, Malaysia. The heavy metals studied included Cd, Fe, Pb, Zn and Cu. The findings indicated that the mean concentrations found in the dissolved form for surface waters were in decreasing order of Fe>Zn>Pb~Cu>Cd. A similar trend was also recorded for the particulate form i.e., Fe>Zn>Pb~Cu>Cd. In terms of vertical distribution, most of the heavy metals showed a trend of increasing concentrations from the surface to the bottom waters. The main sources of heavy metals were from anthropogenic activities such as discharge of untreated sewage, surface runoff and boat activity. However, the levels of dissolved heavy metals were still lower compared to other study areas in Malaysia. The dissolved heavy metal concentrations were equivalent with Class II based on the National Water Quality Standard for Malaysia.