Despite many good policies and institutions, the coastal environment of Langkawi continues to deteriorate. This could be due to lack of effective governance as well as unregulated waste discharge. Evidences collected from the literature during 1996 to 2013 also revealed a significant increase in the concentrations of Zn (R2 = 0.78) and Pb (R2 = 0.12) in the sediment. This appears to be the result of large volume of terrestrial runoff that brings these metals originating from extensive anthropogenic activities. It is a vital indicator of coastal pollution. It is a matter of concern that in many cases Pb concentration in the sediment exceeded the world average value 20 μg/g as well as Canadian Interim Sediment Quality Standard of 35 μg/g for the coastal areas. Similarly, the metal pollution index (MPI) measured over a period of 2007 to 2009 in fish also indicated an increasing trend of pollution in Langkawi. The maximum MPI value (4.87) was recorded in Spanish mackerel. Since pollution of coastal environment has serious implications for marine biodiversity and health of seafood consumers, measures are required to address this problem. Use of constructed wetland might be effective in reducing the coastal pollution as this will filter the effluent and waste before their mixing with the coastal water. Furthermore, enabling the stakeholders to play the environmental stewardship role will ensure better governance of coastal ecosystem and effective implementation of policies, envisaging an improved monitoring of waste/effluent discharge into the coastal marine environment. These measures are among the actions necessary for achieving a sustainable coastal environment of Langkawi.

Alkaloid compounds in Rafflesia cantleyi and host, Tetrastigma tuberculatum were identified using the phytochemical screening method and HPLC technique. The results showed positive test for the host, T. tuberculatum which indicates the presence of alkaloid whereas the screening test for R. cantleyi showed that alkaloid is absenced. Both extract were then subjected to HPLC for alkaloid identification and caffeine was used as standard. The spectroscopic data from HPLC revealed the presence of caffeine in both methanol extracts. The methanol extract of both samples were also tested for antioxidant activity by using DPPH free radical scavenging activity. Result showed that the radical scavenging activity of R. cantleyi and T. tuberculatum are comparable to the standard reference, BHT but higher than the standard alpha tocopherol.

Dangli Waters ecosystem is located at the north of Langkawi UNESCO Global Geopark. Apparently, this area is currently experiencing a significant deterioration of marine habitat. Therefore, 14 stations were set up in this study area to investigate the sediment for metal contents discharged into Dangli Waters using the ecological risk assessment. The sediment samples were collected during four seasons, namely South West Monsoon, First Inter Monsoon, North East Monsoon and Second Inter Monsoon. The spatial distribution pattern of heavy metals in sediment was properly determined as well as the seasonal variation of the contamination. From the results obtained, the average concentration of each heavy metal distributed in the surface sediment of Dangli Waters can be written in decreasing order as Fe>Cr>As>Co>Cd. From the observation, heavy metal concentrations of As was recorded the most higher profiles near to the cement plant production area. Meanwhile, for the pattern of seasonal changes, FIM season was defined as the season with higher concentrations of all metals in the surface sediment compared to other seasons. This is due to highly rainfall distribution and water runoff during this period, leading an increase of sediment deposition into the Dangli Waters. According to the contamination factor (C f ) for each metal, it was shown that some heavy metals such as As were at a risky level with the C f value was higher than 6 (C f >6). However, the degree of contamination (C d ) for each station was classified as moderate (7 ≤ C d < 14), except for ST2 which showed a low degree of contamination. ABSTRAK Ekosistem Perairan Dangli terletak di utara Langkawi UNESCO Geopark. Jelas sekali, kawasan ini sedang mengalami kemerosotan habitat marin yang amat ketara. Oleh yang demikian, 14 stesen kajian telah diwujudkan di perairan ini bagi mengkaji dan mengenal pasti taburan kepekatan logam berat yang dilepaskan ke Perairan Dangli dengan menggunakan penilaian risiko ekologi. Persampelan sedimen permukaan laut dijalankan ketika musim Monsun Barat Daya, Peralihan Monsun Pertama, Monsun Timur Laut dan Peralihan Monsun Kedua. Secara amnya, corak sebaran dan taburan logam berat dalam sedimen serta variasi bermusim ke atas kontaminasi telah diteliti dengan sempurna pada sepanjang tempoh kajian ini dijalankan. Daripada keputusan yang diperoleh, purata taburan kepekatan setiap logam berat di dalam sedimen permukaan Perairan Dangli boleh dinyatakan dalam urutan menurun iaitu Fe> Cr> As> Co> Cd. Daripada pemerhatian, kepekatan logam berat bagi As mencatat profil kepekatan yang paling tinggi berhampiran dengan kawasan kilang pengeluaran simen. Manakala bagi corak perubahan musim pula, FIM ditafsirkan sebagai musim yang mempunyai purata kepekatan yang lebih tinggi bagi semua logam berbanding musim-musim yang lain. Ini adalah disebabkan oleh taburan hujan dan aliran air daratan yang sangat tinggi pada tempoh ini yang membawa kepada peningkatan pemendapan sedimen ke dalam Perairan Dangli. Menurut faktor pencemaran (C f ) bagi setiap logam, i...

Interpolation map of salinity is a helpful scientific instrument for environmental monitoring and for social economic development especially for the community who lived in Sungai Merbok. This research was conducted to develop a spatial model of salinity using spline interpolation technique. 20 sampling stations were randomly set up to measure the level of salinity using YSI 650 Multiparameter Display System (MDS). Quantitative analysis of standard regression and error index were used to evaluate the developed model. The research found that the tension splines type performed better than regularized splines type. The local government and community, who live in Sungai Merbok, can use the developed map of salinity for guidelines and future development of Sungai Merbok, Kedah.