Seng-Chee Poh

University of Malaysia, Terengganu | umt · Faculty of Science and Marine Environment

Surface phytoplankton community, abundance, and species spatial distributions were investigated in the Malacca Straits (MS) of Peninsular Malaysia during the late northeast monsoon (March) and southwest monsoon (August) in 2019 to understand factors controlling their community dynamics. This study reveals that the monsoonal transitions lead to chan...

Material fluxes at the land-ocean interface impact seawater composition and global cycling of elements. However, most attention has been focused on the fluvial dissolved fluxes. For elements like lead (Pb), whose fluvial particulate flux into the ocean is two orders of magnitude higher than the dissolved counterpart, the role of particulates in ele...

The marine aquaculture industry has caused a suite of adverse environmental consequences, including offshore eutrophication. However, little is known about the extent to which aquaculture effluents affect nearby wetland ecosystems. We carried out a field experiment in a mangrove stand located between two effluent-receiving creeks to estimate the ex...

Mangrove species are undergoing environmental changes from nutrient-poor to enrichment due to the large nutrient input. The potential difference in adaptive strategies between the slow- and fast-growing species may lead to great changes in species interaction and ecosystem stability. This study aims to test whether the slow-growing species Aegicera...

Affordable, highly precise, and accurate CO2 sensor is a prerequisite for more extensive CO2 measurements in various environmental settings, and thus more accurate local and global carbon budgets. Here, we propose the use of an autonomous system for the detection of CO2 concentration (mole fraction), appropriate for inland freshwater and eutrophic...

Marine debris, including plastic litter in the marine environment, is a global and multidisciplinary challenge. This report highlights successful policies and good practices within the context of the APEC Roadmap on Marine Debris launched in 2019. The report consists of recommendations and highlights from the APEC Sustainable Coastal Cities Symposi...

Crown-of-Thorns starfish (COTs), Acanthaster cf solaris is known as one of the most significance threats in coral reef ecosystem. During the COTs outbreak it caused extensive coral mortality and consequently lead to loss of habitat in other reef-associated organisms. It is important to investigate the environmental tipping point on COTs early life...

Mangrove species are undergoing environmental changes from nutrient-poor to enrichment due to the large input of external nutrients. The potential difference in adaptive strategies between the slow- and fast-growing species may lead to great changes in species interaction and ecosystem stability. This study aims to test whether the slow-growing spe...

Mangrove species are undergoing environmental changes from nutrient-poor to nutrient enrichment due to the large input of external nutrients. The potential difference in adaptive strategies between the slow- and fast-growing species may lead to great changes in species interaction and ecosystem functioning. This study aims to test whether the respo...

The identification of nitrogen sources and cycling processes is critical to the management of nitrogen pollution. Here, we used both stable (δ15N-NO3-, δ18O-NO3-, δ15N-NH4+) and radiogenic (222Rn) isotopes together with nitrogen concentrations to evaluate the relative importance of point (i.e. sewage) and diffuse sources (i.e. agricultural-derived...

The permeable (sandy) sediments that dominate the world’s coastlines and continental shelves are highly exposed to nitrogen pollution, predominantly due to increased urbanisation and inefficient agricultural practices. This leads to eutrophication, accumulation of drift algae and changes in the reactions of nitrogen, including the potential to prod...

Estuaries have been identified as sources of nitrous oxide (N2O) emissions to the atmosphere but questions remain as to which production pathway(s) govern the oversaturation of N2O observed in most estuaries worldwide. Here, we use a suite of nitrate and N2O isotopes, as well as the 15N site preference signatures of N2O to assess (1) the relative i...

Dissolved inorganic carbon (DIC) is an important parameter of the marine carbonate system. Underway analyses of DIC are required to describe spatial and temporal changes of DIC in marine systems. In this study, we developed a microvolume flow detection method for the underway determination of DIC in marine waters, using gas-diffusion flow analysis...

The role of permeable sediments and subterranean estuaries as coastal nutrient filters is a question of key interest, particularly in areas with high nitrogen loadings. Here, we evaluated the effectiveness of a sandy subterranean estuary in cycling and removing nitrate using stable isotopes of N and O at natural (δ15N‐NO3− and δ18O‐NO3−) and enrich...

We present precipitation isotope data (δ2H and δ18O values) from 19 stations across the tropics collected from 2012 to 2017 under the Coordinated Research Project F31004 sponsored by the International Atomic Energy Agency. Rainfall samples were collected daily and analysed for stable isotopic ratios of oxygen and hydrogen by participating laborator...

This study aims to determine the composition of BTEX (benzene, toluene, ethylbenzene and xylene) and assess the risk to health at different sites in Malaysia. Continuous monitoring of BTEX in Kuala Lumpur City Centre, Kuala Terengganu, Kota Kinabalu and Fraser Hill were conducted using Online Gas Chromatograph. For comparison, BTEX at selected hots...

This manuscript describes a facile and environmentally benign protocol for the acetylation of various alcohol and amines catalyzed by onion peel ash under a base- and solvent-free condition. Various acetates were successfully prepared from the alcohols and amines using onion peel ash as a catalyst and the end-products were obtained in good to excel...

Anabas testudineus (Climbing Perch) is commonly eaten by Malaysians due to its tender flesh and tasty flavor. Usually, it is either freshly cooked or made into various dish including fermented fish called pekasam. This study was done to determine proximate composition, macromineral composition and micromineral composition in climbing perch from 3 s...

The objective of this study was to identify the spatial and temporal variabilities of selected nutrients in the Setiu Wetlands Lagoon (SWL), Malaysia. Water samples were collected quarterly at ten monitoring sites. This study presents results from a 10-year field investigation (2003 to 2010 and 2014 to 2015) of water quality in the SWL. For the spa...

Bisenols and its derivatives are attractive heterocyclic compounds exhibiting a wide range of biological properties, including anticancer, antipyretic and antimicrobial characteristics. Many catalytic systems have been reported to enhance the synthesis of bisenols, but these catalytic systems sufer from several drawbacks, such as the use of externa...

Groundwater discharge can be a significant pathway for dissolved nutrients to surface water and thus can bring forth important implications to the coastal biogeochemical cycles. Discrete sampling of radon concentrations at several locations along an inter-ridge drainage off Setiu Wetlands were carried out to estimate the fluxes of groundwater disch...

Waste shipping oil, a mixture of used lubricating oil and seawater derived from ship engine operation, was tested for its potential to be converted into a fuel product via an innovative microwave-assisted pyrolysis approach using a reaction bed of activated carbon. Higher carbon to waste ratio was found to have beneficial effects in promoting pyrol...

A study was carried out to evaluate the extent of total petroleum hydrocarbon (TPH) and oil and grease (O & G) pollution in the waters of Ramsar Gazetted mangrove area Johor, during monsoon (February) and post-monsoon (May), 2013. The concentrations of TPH obtained using UV-fluorescence spectroscopy ranged between 6.50-80.3 (mean 20.2 ± 15.7) μg L⁻...

A soil pollution assessment of heavy metal Zn, Cu, Cr, Cd, Ni and Pb was carried out in Kuala Terengganu, Malaysia. A total of 245 surface soil samples were sampled and have been subjected to a total digestion and analyzed by inductive couple plasma-optical emission spectrometry (ICP-OES). The contamination of the soils was assessed on the basis of...

Water availability is a key determinant of the zonation patterns in estuarine vegetation, but water availability and the use of different water sources over space and time are not well understood. We have determined the seasonal water use patterns of riparian vegetation over an estuarine ecotone. Our aim was to investigate how the water use pattern...

We report on circular beach mounds, which we have called 'Wonky Mounds' in colloquial reference to locally known seafloor depressions. Two mounds have been identified in the intertidal zone off of North Stradbroke Island, located in Moreton Bay near Brisbane, Australia. They are persistent sand mounds with a diameter of 5-6m and a height of ca. 30c...

Results from the present study in Kuala Terengganu, Malaysia indicated a significant spatial variation but generally the total suspended particulate concentrations (mean = 17.2-148 microg/m(3)) recorded were below the recommended Malaysia guideline for total suspended particulate (mean of 24-h measurement = 260 microg/m(3)). Some of the elemental c...

Total concentration of five trace metals (Cu, Mn, Cd, Pb and Zn) and two major elements (Al and Fe) as well as soil parameters (soil organic matter, pH and cation exchange capacity) were measured in soils of Kuala Terengganu town center. 40 surface soils (0-20cm) were collected during the month of August, 2005. The soil samples (< 600µm) were subje...

Instrumental neutron activation analysis was used for the determination of trace elements in airborne particulate matter (PM10) for air pollution monitoring. For the collection of air samples, the PM10 high volume sampler unit and Whatman 41 cellulose filter papers were employed. Samples were collected at 13 selected sampling sites covering areas i...

Concentrations of Cu, Mn, Cd, Pb, Zn, Fe and Al in indoor dusts and outdoor soils from nurseries located in industrial, town and village area of Dungun district were determined by Atomic Absorption Spectroscopy (AAS) following the acid digestion of the respective soil and indoor dust sample. The range of metals observed in soils were 0.46-46.9 µg/g...

Phosgene poisoning can give rise to increased permeability pulmonary oedema and death. The gas was used in chemical warfare during World War I. In peacetime, cases of acute phosgene poisoning have been reported due to accidental exposure resulting from fire extinguisher use, the use of chemical paint removers and the inadvertent use of trichloroeth...

The Nerus River passes through the Setiu and Kuala Terengganu districts, on the east coast of Peninsular Malaysia. It passes through the populated urban area of northeastern Kuala Terengganu and receives and carries different kinds of agricultural and urban solid and liquid wastes produces by agricultural based industries and domestic sewage. The o...