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Environmental pollution by heavy metals is a serious threat to human and ecosystem. Accumulation of heavy metals in the biota may pose hazardous impact on public health and other living organisms. By using gastropods Neritasp as bio-indicator, the levels of heavy metals in their soft tissues can determine the contamination of heavy metals in the Tanjung Lumpur Mangrove along the Kuantan River. The aim of this study is to identify copper, cadmium, chromium and iron accumulated in the tissue of Neritasp, to investigate the concentration of the copper, cadmium, chromium and iron in the molluscan tissue among the different sizes of gastropod Neritaspand to compare the concentrations of heavy metals in a gastropod Neritasp tissue among the different stations of Kuantan River, Pahang. Gastropods of Neritasp were randomly collected along the river. The tissues of gastropods were digested with nitric acid. Then, concentration of copper, cadmium, chromium and iron were analyzed by using flame atomic absorption spectrophotometer (AAS) model Perkin Elmer SIMAA 6100 graphite furnace. Neritasp accumulate copper the most in their tissues compared to other heavy metals. The concentrations are around 189.8 µg/ L – 247.95 µg/ L. The highest concentration of copper is in Station 3 which is at 241.67 µg/ L. The second highest concentration is iron or ferrum where the concentrations are around 121.25 µg/ L – 174.55 µg/ L. Station 3 was identified to have the highest concentration of iron at 161.12 µg/ L. Followed by, chromium which the concentrations are around 23.49 µg/ L – 46.15 µg/ L. The highest concentration of chromium is Station 1 at 34.82 µg/ L. The lowest concentration of heavy metals is cadmium which is around 8.69 µg/ L – 18.46 µg/ L. Also, Station 1 showed the highest concentration of cadmium at 17.56 µg/ L. This study can be used to identify contamination of heavy metals in marine zone by using bio-indicator to avoid environmental perturbation.

A study on physicochemical parameters and distribution of phytoplankton communities was carried out at Kuantan estuary, Pahang, Malaysia. The study was carried out in September, 2011 and November, 2011 to determine the spatial distribution of phytoplankton from three different stations during the pre-monsoon and monsoon seasons. The phytoplankton and water quality were analyzed using standard method outlines by APHA, 1998. The temperature recorded was between 27.29 oC to 29.33 oC, pH was from 6.96 to 8.24, conductivity range from 33.50mS/cm to 47.85mS/cm, dissolved oxygen ranged was from 4.25 mg/L to 5.84 mg/L, biochemical oxygen demand was from 3.37 mg/L to 1.60 mg/L, salinity range from 21.01 ppt to 30.72 ppt, total dissolved solids range from 21.80 g/L to 31.60 g/L and total suspended solids range from 0.024 to 0.044. The nitrite concentration was range from 0.078 mg/L to 0.088 mg/L during monsoon while in the pre-monsoon seasons the range was from 0.018 mg/L to 0.025 mg/L. Similarly, ammonium concentration was from 0.3056 mg/L to 0.0670 mg/L. The phosphorus content was range from 0.0110 mg/L to 0.0897 mg/L. The pre-monsoon season phytoplankton (1466 Cells/L) was found to be higher than the monsoon season phytoplankton (644 Cells/L).

Surface sediments collected from seven estuarine mangrove forests of Terengganu region (100 sampling points) were anaylzed for Pb, Cu and Zn using the sensitive Inductively Coupled Plasma Mass Spectrometer (ICP-MS). The average concentration of Pb, Cu and Zn were 10.5[+.or.-]7.12 [micro]g [g.sup.-1] dry weights, 31.1[+.or.-]16.5 [micro]g [g.sup.-1] dry weights and 20.8[+.or.-]13.3 [micro]g [g.sp.-1] dry weights, respectively. The statistical analysis of Pearson correlation matrix has proved that there is a significant relationship between the metal concentration and the grain size. The concentration of Pb, Cu and Zn decreased with the decrease of mean size particle, suggesting their association with the fine fraction of the sediments. In this study, Enrichment Factors (EF) were calculated to assess whether the concentrations observed represent background or contaminated levels. The analysis suggests that all studied elements were considered to be dominantly terrigenous in origin. Data obtained also provides a scientific discovery and data for a better understanding and proper management of the mangrove forests of Terengganu. Key words: Surface sediment, lead, copper, zinc, mangrove forest, enrichment factor, INTRODUCTION Mangrove sediments are anaerobic and reduced, as well as being rich in sulphide and organic matter. They therefore favour the retention of water-borne heavy metals (1), (2) and the [...]

Nitrate and phosphorus in wastewater contribute to health and environmental threats as they are linked to illnesses as well as ecosystem disruption via algal blooms in contaminated water bodies. Based on above perspectives a comparative study was conducted on three local freshwater microalgae:Chlorella vulgaris, Spirulina platensis and Scenedesmus quadricauda to evaluate their effects on nitrate and phosphorus removal from municipal wastewater sludge (MWS). Algae performance in removing nitrate and phosphorus was evaluated by measuring nitrate and phosphorus content of MWS incubated with the strains for 7 days. Instantaneous readings were taken every 48 hours to determine periodic levels of the nutrients phosphate and nitrate. BOD5 was also evaluated to identify the strain with the most robust growth that would demand for oxygen the most in the dark. Spirulina platensis was shown as the most efficient microalgae to reduce nitrate in MWS and the best-growing among the three strains, while Chlorella vulgaris removed phosphorus the most effectively. Thus Spirulina and Chlorella could be potential candidates by showing their intrinsic merit for the reduction of phosphate and nitrate in wastewater treatment. ABSTRAK: Nitrat dan fosforus dalam air sisa menggugat kesihatan dan mengancam alam sekitar memandangkan ia berkait dengan penyakit-penyakit serta gangguan terhadap ekosistem melalui pembiakan alga dalam air yang tercemar. Berdasarkan perspektif di atas, satu kajian perbandingan telah dijalankan terhadap tiga mikro alga air tawar tempatan : Chlorella vulgaris, Spirulina platensis dan Scenedesmus quadricauda untuk dinilai kesannya terhadap penyingkiran nitrat dan fosforus dari enap cemar air sisa bandaran (municipal wastewater sludge (MWS)). Kebolehan alga dalam penyingkiran nitrat dan fosforus dikaji dengan menyukat kandungan nitrat dan fosforus dalam MWS yang dieramkan dengan strain ini selama 7 hari. Bacaan serta-merta diambil setiap 48 jam untuk menentukan tahap berkala nutrien fosfat dan nitrat. BOD5 juga dinilai untuk mengenal pasti strain yang membesar dengan cepat yang memerlukan bekalan oksigen paling banyak dalam gelap. Spirulina platensis dikenal pasti sebagai mikro alga yang paling cekap dalam pengurangan nitrat dalam MWS dan paling cepat tumbesarannya, manakala Chlorella vulgaris menyingkir fosforus dengan paling berkesan. Maka Spirulina and Chlorella berpotensi dalam mengurangkan fosfat dan nitrat dalam rawatan air sisa.