Assessment of Spatiotemporal Variations in Water Quality of Tasik Chini Using Multivariate Statistical Techniques

A study was conducted to evaluate the physicochemical parameters and heavy metals concentration level in Tasik Chini water. The sampling waters were analysed according to standard methods and procedures. The analysis of metals concentration was done using ICP-MS (Inductively Coupled Plasma Mass Spectrometry). The DOE-WQI (Department of Environment Water Quality Index) framework and multivariate statistical methods were adopted in order to determine the spatial variations of water quality variables, levels of water pollution and contamination sources. The study results were compared with classification based on National Water Quality Standard (NWQS) for Malaysia. Results revealed that the dissolved oxygen (DO) value was low (4.68 mg/L), while the value of chemical oxygen demand (COD), biological oxygen demand (BOD) and total dissolved solids (TDS) was high, 26.10 mg/L, 2.92 mg/L and 22.93 mg/L respectively. High turbidity was recorded in mining area (35.76 NTU) in wet season. The DOE-WQI value classified the lake from slightly polluted (class II) to polluted (class III) by anthropogenic activities. The Principal Component Analysis (PCA) was applied to evaluate the correlation of each element and the major sources of contamination in the lake. Cluster analysis (CA) grouped the ten monitoring stations into three clusters of pollution levels based on similarities in water quality variables. The average concentration of heavy metals in the Tasik Chini water was low pollution levels. This study quantified that the important factors affecting these metal concentrations in lake water were the mining operations and the impact of rainy season. Therefore, this research could be valuable in providing accurate data as baseline information for future references.