Formulating Specific Water Quality Criteria for Lakes: A Malaysian Perspective

Monitoring water quality of inland water bodies such as lakes, reservoirs and ponds throughout Malaysia is important to ensure that these water bodies can be managed sustainably for their ecosystem functioning and services. Determining the quality of these water bodies for different uses is limited due to the unavailability of specific criteria or standards for such water bodies in the country. The aim of this study is to develop national water quality criteria and guidance values for lakes to enhance the water quality of the water bodies in Malaysia. The work is based on a literature review and a consensus among experts from the various stakeholders’ consultative sessions. The criteria were divided into four specific uses which aim at protecting the health of human and aquatic life. The criteria and standards are targeted for non‐regulatory purposes to promote lake quality monitoring by various stakeholders. More than 20 parameters were identified in the lake criteria to determine the classification. The identification of parameters and limits for the standards, however, was limited by data availability and appropriate understanding of the water body characteristics. The role of the criteria and their limitation was also discussed

Assessing the Hydrodynamic Pattern in Different Lakes of Malaysia

Hydrodynamic simulations using three-dimensional numerical model were carried out in three different shallow tropical lakes to understand the characteristics of water movement in the respective water bodies. The models were based on meteorological data from the nearest stations and calibrated with current measurement, temperature, or water-level data. The results show good agreement between measured and simulated velocities and/or temperature at certain depth. This study found that the major driving forces of the hydrodynamic pattern were different in the three lakes. Hydrodynamic simulations showed that Bukit Merah and Durian Tunggal reservoirs were more sensitive to wind-driven motion. Floodplain lakes, such as Bera Lake, are more sensitive to flood inflow by the main river during the monsoon season. Convective motion driven by water temperature gradient was important for Bukit Merah and Bera Lake

Seasonal water quality and trophic status of shallow lentic waters and their association with water levels

Extreme hydro-climatic changes associated with floods and drought greatly influence the ecosystem dynamic of tropical lakes in Malaysia, resulting in negative impacts on their water quality and trophic status. This study examined the seasonal changes in water quality and trophic state connected to hydro-ecological changes in a natural lake and two reservoirs. Water levels in the three water bodies varied with changes in rainfall regime, and water regulation for irrigation or water supply. Multivariate analysis of variance showed a significant relationship between season and temperature, pH, conductivity, total nitrogen and chlorophyll-a (p < 0.05). Drought events and the associated period of low water levels were characterized by high temperature, conductivity and chlorophyll-a levels in these shallow lakes, which probably led to high photosynthetic rates with concomitant increase in dissolved oxygen and pH and decrease in total nitrogen concentration. Elevated chlorophyll-a and total phosphorus concentrations were also associated with drought events and the decrease in water level in Bukit Merah Reservoir, possibly due to the release of phosphorus from internal loading resulting from sediment re-suspension by wind. Salinity increase in Durian Tunggal Reservoir during dry season was possibly due to seawater intrusion into river. During the rainy season, transparency in Bera Lake and Bukit Merah Reservoir was strongly influenced by the influxes of the main river that transported elevated levels of suspended solids and nutrients

Assessment of Water Quality Parameters and Heavy Metals Analysis at Universiti Sultan Zainal Abidin Besut Campus Lake

Water is the most crucial element for living organisms as a component for survival. Even water has become the habitat for some organisms. Therefore, assessment of water quality is vital to keep water in good condition. This study aimed to determine the water quality of Besut Campus Lake by assessing the physicochemical parameters. Water Quality Index (WQI) is related to the process of determining the status class of water according to beneficial use, with a higher index value indicate good water quality. National Lake Water Quality Standard (NLWQS) was also applied in determining the category of enclosed water systems like ponds and lakes. Water samples were taken from sampling stations at Besut Campus Lake and undergo in – situ and ex–situ analyses involving nine physicochemical parameters. In addition, heavy metal analyses were conducted in the laboratory according to American Public Health Association (APHA) methods. Based on the research conducted, Besut Campus Lake was classified as Class Ⅱ with an index value of 78.23 from the Malaysia Water Quality Index (MWQI), which means recreational activities can be conducted within the lake area involving body contact. Meanwhile, according to National Lake Water Quality Standard (NLWQS), the water category of Besut Campus Lake can be categorised as Category B, which means recreational activities with secondary body contact. Further in-depth analyses involving other microbiological parameters should be carried out before the water can be recommended for primary contact recreation such as swimming

Comparative limnology of natural and man-made tropical lakes

This paper assessed and compared physicochemical profiles and biodiversity indices of two shallow lakes namely the natural Bera Lake and Bukit Merah reservoir in Peninsular Malaysia. Variations in relation to hydro-meteorological variables, including rainfall, wind speed and air temperature were also measured during the field sampling. The results showed clear distinctions between natural and man-made lakes in terms of physical and chemical properties of lake waters and their relationships to the hydro-meteorological dynamic. Persistent oxygen and temperature differences between the epilimnion and hypolimnion were clearly detected in Bukit Merah reservoir under low winds and strong heat. Oxycline also persist during flooding or high turbidity levels indicating their enriched bottom waters. On the other hand, the natural Bera lake showed temporary stratification during the dry season with low winds but the water columns were thoroughly mixed during the wet season when the water temperature was lower and wind speed was higher. Plankton diversity in Bera lake was significantly higher (p <0.05) than the Bukit Merah reservoir, probably due to the much longer history of the natural lake compared to the man-made one. Due to the longer residence time of the reservoir compared to the natural lake, the former tends to be more vulnerable to eutrophication if subjected to uncontrolled nutrient enrichment

Planktonic microcrustacean community structure varies with trophic status and environmental variables in tropical shallow lakes in Malaysia

A study was conducted to evaluate planktonic microcrustacean species composition, abundance, and diversity in lakes with different trophic status and to determine the relationship between microcrustacean community structure and lake environmental conditions. This study hypothesized that there are correlations between eutrophication levels and microcrustacean community structures in a lake. Three shallow lakes of different trophic status (Sembrong, Putrajaya and Subang lakes) were selected for this study. Two-Way Analysis of similarities (ANOSIM) revealed differences in microcrustacean diversity and density amongst lakes, where the hypereutrophic condition in Sembrong lake resulted in the lowest diversity but the highest density of microcrustaceans. Similarity percentage (SIMPER) analysis identified the discriminator species among lakes where the domination of small-sized microcrustaceans was observed in lakes with high levels of eutrophication; the hypereutrophic Sembrong lake (Ceriodaphnia cornuta, 74.0%); the meso-eutrophic Putrajaya lake (Bosmina longirostris, 46.9%; C. cornuta, 19.4%). Chlorophyll a, total phosphorus and water transparency showed significant roles in the distribution of microcrustaceans. The canonical correspondence analysis (CCA) scores indicated that small-sized C. cornuta and B. longirostris were related to the eutrophic conditions of lakes. This study elucidated that the lake trophic status could be one of the main factors contributing to the community restructuring of microcrustaceans in tropical lakes

A preliminary study of marine water quality status using principal component analysis at three selected mangrove estuaries in east coast Peninsular Malaysia

This research presents marine water quality status in three different mangrove estuaries. The objective of this study is to evaluate the surface water quality of three estuaries in east coast Peninsular Malaysia. The parameters measured were Dissolved Oxygen (DO), pH, Biochemical Oxygen Demand (BOD), total dissolved solid (TDS), ammonium (NH4-N), turbidity (TUR), total suspended solid (TSS) and coliform. Monthly sampling was performed during the dry season, from June 2016 until September 2016. Data were analysed using principal component analysis (PCA). PCA yielded two PCs where VF1 forms strong factor loadings for pH, NH4-N, SAL, and TDS signifying saltwater intrusion in mangrove area. VF2 designed strong factors of BOD, TUR and Coliform and strong negative loading of DO indicating anthropogenic pollutions in the area. This study output will be a baseline setting for future studies in mangrove estuary marine water quality. Mangrove marine water samples of future monitoring studies in mangrove estuary will benefit by enabling understanding of pollution loading and coastal water quality. It is essential to plan a workable water quality modelling as powerful tool to simulate marine water quality and forecast future consequences to facilitate mangrove biodiversity conservation

Fisheries practices and fish diversity in Muda and Beris Lakes: a preliminary survey study

Beris and Muda are two artificial lakes that have shifted from lotic to lentic system. Despite both lakes were created for irrigation and source of drinking water, they provide fish habitat for human consumption. This study was carried out to find out the effect of different management approaches on fish in the studied lakes. Muda Lake was utilized for commercial fisheries; this lake hosts around 50 active fishermen compared to Beris that has all part-time fishermen. The catch and the existence of fish landing centre makes the Muda a successful lake for commercial fisheries. In contrast, Beris Lake has also developed its fisheries activity, but concentrates more on the recreational aspect which is well developed at this lake. The existence of many chalets providing boats for sport fishing makes Beris Lake more successful than Muda Lake. The study found a contrasting impact of introducing different alien species where may cause benefit at Muda Lake such as increasing fish stocks of Tilapia (Orechromis spp.) but developed problems in Beris Lake when Toman (Channa micropeltes) was introduced to this lake which reduced the number of native fish species compared to previous studies. This study finds that different methods of fishery management and the introduction of alien species may affect the fisheries activities and fish diversity in those lakes

Perception and Willingness-to-Pay on conservation of lake basin under the impact of climate change – a comparison between urban and rural tropical lake

Climatic changes are affecting the lake hydrological regime, including the associated drought and floods within the drainage basins. Assessing the value of damages to ecosystem services within the lake basin concerning the climatic changes is difficult due to the numerous ecosystem services provided by every lake basin. This study uses a Contingent Valuation Method to determine the willingness-to-pay (WTP) for lake conservation programs for addressing climate extreme impacts on urban and rural tropical lakes. Surveys using structured questionnaires were carried out around Putrajaya, the Federal Territory of Putrajaya (urban lake) and around Muda Lake, Kedah (rural lake). Respondents in both lake basins significantly differed in terms of education and income level. However, the WTP values for contribution to address climate change measures in both lakes were similar (around USD3). About 62% of respondents in both lake basins were willing to pay and contribute to climate change and conservation trust funds for preventing impacts on the lake. For Putrajaya Lake, the main reason for WTP was the need for managing lake and wetland, and their biodiversity while for Muda Lake, the main reason for WTP was the need for circumventing deterioration in the lake for future generations

Control limit detection for source apportionment in Perlis River Basin, Malaysia

This study presents the application of selected environmetric in the Perlis River Basin. The results show PCA extracted nine principal components (PCs) with eigenvalues greater than one, which equates to about 77.15% of the total variance in the water-quality data set. The absolute principal component scores (APCS)-MLR model discovered BOD and COD as the main parameters, which indicates the measure of the agricultural pollution in the Perlis River Basin, the hierarchical agglomerative cluster analysis (HACA) shows 11 monitoring stations assembled into two clusters in accordance with similarities in the concentration of BOD and COD, which are grouped in P4. The X ̅ control chart shows that the mean concentration of BOD and COD in P4 is in the control process. The capability ratio (Cp) was applied to measure the risk of the concentration in terms of the river pollution in a subsequent period of time using the limit NWQS