- School of Biological Sciences,
Universiti Sains Malaysia,
11800 Penang,
MALAYSIA
- My research interest is freshwater ecology with focusing on fish biodiversity and population beside limnology.edit
Research Interests:
To acquire baseline data for a remote Pergau Hydroelectric Power Plant reservoir, a hydrological and water quality examination of feeder rivers and reservoir water was conducted in 2013. The water balance of the reservoir was determined,... more
To acquire baseline data for a remote Pergau Hydroelectric Power Plant reservoir, a hydrological and water quality examination of feeder rivers and reservoir water was conducted in 2013. The water balance of the reservoir was determined, and gauging and sampling were carried out in dry and wet periods. Dilution gauging was used to estimate the feeder river discharge. The total water flow into the reservoir increases nearly fivefold between the dry and wet seasons, while river discharge increases two to fivefold. All of the river intakes had Class 1 NWQS water quality. The lake's water quality was Class 1 up to the top 3 meters, but below that, at some places, the water quality deteriorated to Class II. In the dry season, the trophic status of Pergau Reservoir is eutrophic as measured by TP (59.21) and chlorophyll-a (52.36) and the TSI (SD) was 53.93 Eutrophication occurrences will cause serious limitations in water use applicability. This research contributes to the biogeographical and limnological understanding of the Pergau catchment, as well as laying the groundwork for more sophisticated hydro-ecological investigations. Anthropogenic activities, together with runoff from agricultural operations and the presence of algae, are some of the sources of contamination noted in the study. Stricter legislation, stricter enforcement of current standards, matching of non-technical and technosocial remedial actions, and education are among the recommendations made for the Pergau Reservoir's protection.
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TNB Research (TNBR) was conducted a pilot study on the commercialization of catch and release sport fishing in Puah Reservoir, a new hydroelectric project within the Hulu Terengganu Hydroelectric Station (HTHS). The objective of this... more
TNB Research (TNBR) was conducted a pilot study on the commercialization of catch and release sport fishing in Puah Reservoir, a new hydroelectric project within the Hulu Terengganu Hydroelectric Station (HTHS). The objective of this study is to evaluate the impact of the sport fishing programme on socio-economic benefit and its potential as a component of Non-Timber Forest Products (NTFPs). The evaluation was conducted in two phases, from November 2017 to May 2018 (Phase 1) and October 2018 to December 2019 (Phase 2), which covered the reservoir and its catchments, such as Terengganu Mati, Limbang, Pelagong, and Sireh rivers. The information was gathered from registered anglers who fished 12 days per month, using two boats with a maximum of two anglers per boat and casting methods from 0700 to 1630. The results show that November 2017 had the highest average of fish strikes per angler with a value of 11. This value was recorded as a standard for the best strikes at the Puah Reservo...
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Telemetry is an emerging method to study fish ecology and a reliable tool that provides useful information for managing and conserving aquatic fauna and river habitats. However, the reliability of telemetry depends on several technical... more
Telemetry is an emerging method to study fish ecology and a reliable tool that provides useful information for managing and conserving aquatic fauna and river habitats. However, the reliability of telemetry depends on several technical factors. Implantation of the acoustic transmitter is one of the major aspects that ensure the survivability of the animal subject when released into the wild. Studies on the technicalities involving telemetry methods are limited; therefore, this study investigated the surgical insertion of an acoustic transmitter into the peritoneal cavity of Channa lucius and Neolissochilus soroides or locally known as Bujuk and Tengas. A severity index was used to rate the appearance of surgical wounds observed on the day of release into the river. Fish mortality and complications such as bleeding were not observed in both species post-surgery. The progress and prognosis of wound healing of C. lucius were better compared to N. soroides, with generally lesser inflamm...
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This study aims to determine the level of nine trace elements – As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn in liver, gill and muscle of Oreochromis niloticus in Bukit Merah Lake (BML). The concentration of trace elements was measured using... more
This study aims to determine the level of nine trace elements – As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn in liver, gill and muscle of Oreochromis niloticus in Bukit Merah Lake (BML). The concentration of trace elements was measured using Inductively Coupled Plasma-Optical Emission Spectrometers (ICP-OES). Cd and Ni were found below the detection level, while Cr was only detected in gill and muscle tissues. The Metal Pollution Index (MPI) established were liver > gill > muscle. The ranking order of trace elements in the gills was Fe > Zn > Mn > Pb > As > Cu > Cr. For the liver, the ranking order was Fe > Cu > Zn > As > Mn > Pb, while in the muscle, the ranking order was Fe > Zn > Pb > As > Cu > Mn > Cr. The estimated daily intake (EDI) for all the trace elements in this study was calculated based on 168 g.day–1 of Malaysians’ fish consumption, indicating no potential risk. From the human health point of view, there was no significant non-carcinogenic risk of individual trace elements as evaluated by Target Hazard Quotient (THQ). As indicated by the Hazardous Index (HI), the cumulative effect of all trace elements also suggested no potential of non-carcinogenic risk. The carcinogenic risks assessed from Pb and As were also neglectable and there was no likelihood of getting cancer during one’s life span.
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With a surface area of 15, 200 ha, the Temengor Reservoir, in the northwestern state of Perak was selected among other lakes in Malaysia for the development of a large tilapia aquaculture facility in 2008 due to its favourable... more
With a surface area of 15, 200 ha, the Temengor Reservoir, in the northwestern state of Perak was selected among other lakes in Malaysia for the development of a large tilapia aquaculture facility in 2008 due to its favourable environmental conditions. Tilapia has never been recorded at Temengor Reservoir prior to the establishment of this facility. However, preliminary observations in a previous study detected tilapia species in the natural waters of this lake, strongly suggesting these were escapees from the floating cages which had invaded the natural waters. Following that, a study was conducted to assess the distribution of these escapees throughout the Temengor Reservoir. The cultured tilapias are easily recognizable with elongated mouth and body, and long caudal fin. The sampling was conducted using gill nets. The distribution of the escaped tilapia throughout the Temengor Reservoir was mapped based on previous data and current data on the fish checklist conducted at different sampling points of this lake, and the occurrence (presence/absence) of escaped tilapia was recorded. A comparative analysis was conducted at several number of points among three sampling areas, according to the radii from the fish cage facility; <5km (S1), 5-15km (S2), and >15km (S3). The ANOVA showed significant differences (p<0.05) in Catch per Unit Effort (CPUE) weight between the three sampling areas. As tilapia is a highly successful global invasive species, the presence of tilapia at these and other locations at Temengor Reservoir should be rigorously monitored. Complete eradication of tilapia in the lake is of high urgency. We recommend intensive targeted fishing of the species in the vicinity of the cages and biological control by native predators to preserve and conserve the native fish species at Temengor Reservoir.
Marine fish in Malaysian waters are impacted by various stressors, including resource exploitation, urbanization and industrialization. Therefore, this study examines the fish diversity and distribution at five sampling stations with... more
Marine fish in Malaysian waters are impacted by various stressors, including resource exploitation, urbanization and industrialization. Therefore, this study examines the fish diversity and distribution at five sampling stations with different natural processes and anthropogenic activities in the coastal waters of Pulau Pinang, Malaysia. A total of 669 fish specimens belonging to 47 species from 23 families were collected using drift nets in two sampling periods from October to November 2017 and October to November 2019, respectively. The fish abundance is determined based on the catch per unit effort, CPUE (ind/hour). Among the dominant families, Leiognathidae and Ariidae accounted for 21.22% and 14.44% of the total catch, respectively. Three fish species, namely, Eubleekeria splendens, Anodontostoma chacunda, and Pennahia anea, dominated the catches. The CPUE near the ongoing reclamation projects and landfill was lower than that of the port and industrial areas with mangrove estuaries. The dendrogram clearly differentiated the fish species composition between the reclamation sites and natural shorelines. Given no previous research on the fish distribution along the Pulau Pinang strait featuring different habitat types, this study therefore serves as a contemporary fish assemblage for future research and surveys.
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To acquire baseline data for a remote Pergau Hydroelectric Power Plant reservoir, a hydrological and water quality examination of feeder rivers and reservoir water was conducted in 2013. The water balance of the reservoir was determined,... more
To acquire baseline data for a remote Pergau Hydroelectric Power Plant reservoir, a hydrological and water quality examination of feeder rivers and reservoir water was conducted in 2013. The water balance of the reservoir was determined, and gauging and sampling were carried out in dry and wet periods. Dilution gauging was used to estimate the feeder river discharge. The total water flow into the reservoir increases nearly fivefold between the dry and wet seasons, while river discharge increases two to fivefold. All of the river intakes had Class 1 NWQS water quality. The lake's water quality was Class 1 up to the top 3 meters, but below that, at some places, the water quality deteriorated to Class II. In the dry season, the trophic status of Pergau Reservoir is eutrophic as measured by TP (59.21) and chlorophyll-a (52.36) and the TSI (SD) was 53.93 Eutrophication occurrences will cause serious limitations in water use applicability. This research contributes to the biogeographical and limnological understanding of the Pergau catchment, as well as laying the groundwork for more sophisticated hydro-ecological investigations. Anthropogenic activities, together with runoff from agricultural operations and the presence of algae, are some of the sources of contamination noted in the study. Stricter legislation, stricter enforcement of current standards, matching of non-technical and technosocial remedial actions, and education are among the recommendations made for the Pergau Reservoir's protection.
Heavy metals are rich in seleniferous areas; however, the bioaccumulation and health risk of heavy metals are poorly understood, given the fact that selenium (Se) can inhibit the phytotoxicity and bioavailability of many heavy metals. The... more
Heavy metals are rich in seleniferous areas; however, the bioaccumulation and health risk of heavy metals are poorly understood, given the fact that selenium (Se) can inhibit the phytotoxicity and bioavailability of many heavy metals. The present study investigated the bioaccumulation of heavy metals in the soil–rice system in the Enshi seleniferous area of central China. Soils were contaminated by Mo, Cu, As, Sb, Zn, Cd, Tl, and Hg caused by the weathering of Se‐rich shales. Among these heavy metals, Cd and Mo had the highest bioavailability in soils. The bioavailable fractions of Cd and Mo accounted for 41.84 and 10.75% of the total Cd and Mo in soils, respectively. Correspondingly, much higher bioaccumulation factors (BAFs) of Cd (0.34) and Mo (0.46) were found in rice, compared with those of other heavy metals (Zn 0.16, Cu 0.05, Hg 0.04, and Sb 0.0002). For the first time—to our knowledge—we showed that the uptake of Hg, Cd, and Cu by rice could be inhibited by the presence of Se in the soil. The probable daily intake (PDI) of Se, Cd, Mo, Zn, and Cu through consumption of local rice was 252 ± 184, 314 ± 301, and 1774 ± 1326 μg/d; and 7.4 ± 1.68 and 0.87 ± 0.35 mg/d, respectively. The high hazard quotients (HQs) of Mo (1.97 ± 1.47) and Cd (5.22 ± 5.02) suggested a high risk of Cd and Mo for Enshi residents through consumption of rice. Environ Toxicol Chem 2019;38:1577–1584. © 2019 SETAC
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The tire track eel, Mastacembelus favus, is an economically important freshwater fish in mainland Southeast Asia. Understanding the spatial population structure is important to design an effective and efficient management of the species.... more
The tire track eel, Mastacembelus favus, is an economically important freshwater fish in mainland Southeast Asia. Understanding the spatial population structure is important to design an effective and efficient management of the species. The aim of this study was to investigate the genetic diversity and structure of M. favus populations. In total, 519 individuals from 30 locations across its distribution range were genotyped using a set of eight polymorphic microsatellite loci. Results showed that populations in Mekong and Chao Phraya exhibited higher genetic variability than those from Gulf of Thailand and Malay–Thai Peninsula. Clustering results revealed two evolutionarily isolated groups geographically separated at Northeastern Cambodia; the more widespread group was further divided into two subclusters. The spatial genetic variation and structure of its populations are attributed to the evolutionary history and population dynamics of the species. The study provides important inf...
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A case study of water quality classification at selected freshwater habitats such as rivers, irrigation canals, black water streams and small man made lakes based on fish index were applied. The fishes have different tolerance levels... more
A case study of water quality classification at selected freshwater habitats such as rivers, irrigation canals, black water streams and small man made lakes based on fish index were applied. The fishes have different tolerance levels depend on species and this tolerance levels is also known as fish index which ranging from 0.5-4.5. Generally, the larger values are for fishes that can tolerate in a wide range of environmental changes, while smaller values are for sensitive fishes that cannot tolerate even in a small change in the surrounding area. Therefore, fish index can be used as alternative tools for water quality classification which is more cheaper and easy to use when compared to water quality index
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The effects of the five herbicides propanil, quinclorac, molinate/propanil, 2,4-D amine, and bensulfuron on Odonata diversity and abundance at the experimental rice plots was investigated. A total of 13 Odonata morphospecies belonging to... more
The effects of the five herbicides propanil, quinclorac, molinate/propanil, 2,4-D amine, and bensulfuron on Odonata diversity and abundance at the experimental rice plots was investigated. A total of 13 Odonata morphospecies belonging to two families have been identified. Treated plots exhibited higher species richness (up to 12 species) than the control plot (8 species). Ishnura spp. was the most abundant
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ABSTRACT An intensive fish sampling by using LR-24 Smith-Root Backpack Electrofisher and cast net was conducted at selected headwater streams of the Ulu Muda Forest Reserve (UMFR) from 4 to 5 February 2012. A total of 25 fish species from... more
ABSTRACT An intensive fish sampling by using LR-24 Smith-Root Backpack Electrofisher and cast net was conducted at selected headwater streams of the Ulu Muda Forest Reserve (UMFR) from 4 to 5 February 2012. A total of 25 fish species from nine families were obtained. The species number recorded in the present study is high when compared to the previous studies done in 2003 and 2005 which recorded 11 and 17 species, respectively. Out of this species number, 15 fish species are recorded for the first time herein, making it a total of 41 fish species from 16 families recorded from this forest reserve. However, the inventory is expected to increase as there are many other headwater streams of UMFR not been surveyed as yet.
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This paper discusses the development of an analytical system to monitor the survival of shrimp at the iKERPAN fully integrated aquaculture park, located at the Kuala Kerpan, Kedah. The iKERPAN has to deal with the White Spot Syndrome... more
This paper discusses the development of an analytical system to monitor the survival of shrimp at the iKERPAN fully integrated aquaculture park, located at the Kuala Kerpan, Kedah. The iKERPAN has to deal with the White Spot Syndrome Virus, a kind or shrimp disease which affects the productions of the farm.The farm performs daily data collections, but the data are underutilized due to incapability of people to transform the data into much informative for quick decision makings.Thus, the goal of transferring knowledge of an analytical system is to assist the people to identify some problems that may harm the production of shrimp in systematic ways. The developed analytical system was developed in three main phases.Phase I involved several round table discussion among researchers to recognise the loopholes in data collection procedures and the analyses that had been practices.Next, extensive analytical system was performed in Phase II by transforming all the needed analyses and report...
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Hulu Terengganu Hydroelectric Project (HTHP) involved the construction of two new dams which led to the creation of Puah Reservoir with 60 km 2 surface areas and Tembat Reservoir (1.3 km 2 ). As a result, there are changes of the existing... more
Hulu Terengganu Hydroelectric Project (HTHP) involved the construction of two new dams which led to the creation of Puah Reservoir with 60 km 2 surface areas and Tembat Reservoir (1.3 km 2 ). As a result, there are changes of the existing physicochemical water quality properties from the lotic condition to lentic, which indirectly impact the presence of aquatic organisms, especially fishes at the proposed project areas. The purpose of this paper is to provide the existing fish checklist and conservation status related to future perspective on fisheries management via public stocking. Multiple fishing gears such as long line, different mesh size of gillnets, cast net, and electro-shocker were used in this study covering prior construction, during construction and operation phase of development. No protected fish species under Terengganu Fish Act was sampled during the study. A total of 29 fish species were recorded with cyprinids as the dominant fish family caught in HTHP. The presen...
The drastic changes in hydroelectric reservoir development created a completely new ecosystem that affects the river, particularly in the inundated area. In this study, five Neolissochilus soroides and Channa lucius were surgically... more
The drastic changes in hydroelectric reservoir development created a completely new ecosystem that affects the river, particularly in the inundated area. In this study, five Neolissochilus soroides and Channa lucius were surgically implanted with a unique coded acoustic transmitter to observe the habitat utilisation and movement activity in Tembat Reservoir after the inundation process. All of the individuals were released into the transition zone of the reservoir and observed using passive and active acoustic tracking devices from April to December 2018. Kruskal-Walis test showed no significant difference between the average size of core area for N. soroides and C. lucius, x2(1) = 1.320, p = 0.251. The home range also showed a similar result for N. soroides and C. lucius where there was an insignificant difference, x2(1) = 0.273, p = 0.602. However, duration wise, N. soroides spend more time in the transition zone, R1 (M = 2.71 hrs, SE = 0.38), and C. lucius in the riverine zone, R...
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The shrimp growth and production can be measured through several components such as the harvest ton, mean body weight, survival rate and feed conversion ratio. According to previous studies, the shrimp feed conversion ratio should have a... more
The shrimp growth and production can be measured through several components such as the harvest ton, mean body weight, survival rate and feed conversion ratio. According to previous studies, the shrimp feed conversion ratio should have a positive relationship with their mean body weight. Nevertheless, in real scenario, high feed conversion ratio does not necessarily implies maximum increment of mean body weight. The measurement of those components usually can be influenced by many factors such as climates, stocking density and day of culture. This study in particular explores the effect of climates on productivity of the shrimp species, Penaeus Vannamei and investigates whether feed conversion ratio influences the mean body weight when stocking are done at different climate season. First, the one-way MANOVA was used to measure the effect between the climate seasons and P. Vannamei production. Then, the regression analysis was apply to measure the relationship between P. Vannamei fe...
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Red seaweed Gracilaria sp. is known as ‘Janggut Duyong’ by the local people of Sarawak. This macroalgae iswell-distributed in both temperate and tropical seawaters. Gracilaria sp. could be processed to produce agar forindustrial purposes... more
Red seaweed Gracilaria sp. is known as ‘Janggut Duyong’ by the local people of Sarawak. This macroalgae iswell-distributed in both temperate and tropical seawaters. Gracilaria sp. could be processed to produce agar forindustrial purposes whereas some people consumed it directly and become part of their daily diet. In terms ofecology, Gracilaria sp. is one of primary producer in the seawater and its presence can form habitats to supportother aquatic organisms. Despite its socio-economic and ecological importance, little is known about Gracilariasp. in Sarawak. Hence, this study is designed to: (i) determine the diversity and abundance of Gracilaria in cageculture of Lawas, Sarawak (ii) assess the water quality of the cage culture area where Gracilaria is found and(iii) determine other aquatic organisms that found within Gracilaria population. Three field samplings had beenconducted from October 2013 to November 2014 at cage culture areas of Awat-Awat Village, Lawas, Sarawak.Only sing...
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Red seaweed , one of the largest genus in Division Rhodophyta inhabits Sarawak coastal water. This study was designed to identify the species of using morphological approach and to assess selected water quality parameters in habitats.... more
Red seaweed , one of the largest genus in Division Rhodophyta inhabits Sarawak coastal water. This study was designed to identify the species of using morphological approach and to assess selected water quality parameters in habitats. Three field samplings were carried out in Santubong and Asajaya, Sarawak from November 2013 to December 2014. Overall, three species were identified namely , and , attached to net of cage culture in Santubong and root of mangrove trees in Asajaya. In addition, three different taxa of aquatic macroinvertebrates (polychaete, small crab, bivalve) and single species of red seaweed ( sp.) were observed in assemblages. An estimate of 37% to 40% of the upper part of the cage net in Santubong was covered by seaweeds and only 16% to 20% in Asajaya's mangrove. The study had provided better information on identification of and their habitat in Sarawak. Future work involving DNA barcoding of each species is in progress.
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Out of the 1000 species of freshwater fish documented in the South-East Asian Tropics, 420 species can be found in Malaysia. Based on experimental gill net studies, Perak River recorded a total of 107 fish species, which comprises of 33... more
Out of the 1000 species of freshwater fish documented in the South-East Asian Tropics, 420 species can be found in Malaysia. Based on experimental gill net studies, Perak River recorded a total of 107 fish species, which comprises of 33 families with Cyprinidae as the dominant family, with 43 species. The fluctuating number of species and species replacement in the upstream direction in this river reflects the orientation of the River Continuum Concept. Gradient changes of salinity, habitat heterogeneity, water velocity and riverbed materials are some of the factors that may contribute to the fluctuation and species replacement.
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An inventory study of fishes was carried out from June 2003 to May 2004 at Sungai Enam and Sungai Telang, which was last logged 40 years ago. In spite of the negative impacts of logging, the study recorded a total of 21 fish species in... more
An inventory study of fishes was carried out from June 2003 to May 2004 at Sungai Enam and Sungai Telang, which was last logged 40 years ago. In spite of the negative impacts of logging, the study recorded a total of 21 fish species in these headwaters, comprising nine families. Sungai Telang recorded 19 species with 11 species classified as “locally rare”, whereas Sungai Enam recorded 11 species with nine species classified as “locally rare”. When species from previous studies were included, the total number of species recorded in Sungai Enam and Sungai Telang was 28 and 27 species respectively. The presence of Devario regina, Neolissochilus soroides and Poropuntius smedleyi in all inventory studies conducted indicate that both headwaters are healthy, and function as sources of clean water, nutrient supplies and fish recruits for Temengor Reservoir.
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Seasonal changes of freshwater fish assemblages and environmental factors in Bukit Merah Reservoir were carried out from January-February 2013 (dry season) to March-April 2013 (wet season) by measuring several physico-chemical parameters... more
Seasonal changes of freshwater fish assemblages and environmental factors in Bukit Merah Reservoir were carried out from January-February 2013 (dry season) to March-April 2013 (wet season) by measuring several physico-chemical parameters such as dissolved oxygen (DO), water temperature, pH, water conductivity, total dissolved solids (TDS) and water clarity. 19 fish species comprising of 10 families were collected by using experimental gill nets with different mesh sizes at four different sampling stations. Mean CPUE for total catch and biomass were significantly different between dry and wet season (p < 0.05). Based on a T-test analysis, water temperature, pH and conductivity were significantly different (p < 0.05) between seasons whereas a one-way ANOVA displayed a significant difference in TDS and water clarity between sampling stations (p < 0.05), implicating that those factors did not give major influence towards other parameters in a man-made reservoir. From all fish s...
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Fish from three major rivers namely Pengkalan Chepa, Kelantan, and Galas rivers in Kelantan, Malaysia was caught using gill-nets with separate mesh sizes of 1, 2, 3, and 4 inches, respectively. There were 170 fish collected from the PCR... more
Fish from three major rivers namely Pengkalan Chepa, Kelantan, and Galas rivers in Kelantan, Malaysia was caught using gill-nets with separate mesh sizes of 1, 2, 3, and 4 inches, respectively. There were 170 fish collected from the PCR systems, which represented 18 families and 21 species (2008-2009). The most common fishes, based on total fish captured, were Ikan duri (Arius maculatus) and Puyu (Anabas testudineus). A total of 245 individual fish were collected from KR (2010-2012) which comprised of 7 families and 22 fish species with the highest number of individual fish (51) collected during this survey was the spotted catfish (Arius maculatus). A total of 562 fish specimens representing 12 families and 32 species were captured from riverine monitoring in the GR systems (2008-2010).
Research Interests: Engineering and Fisheries
ABSTRACT Selar crumenophthalmus (bigeye scad) locally known as mushimas, is a widely distributed fish in Maldives. For the biological study, random samples of Selar crumenophthalmus (bigeye scad) were collected from September 2012 to... more
ABSTRACT Selar crumenophthalmus (bigeye scad) locally known as mushimas, is a widely distributed fish in Maldives. For the biological study, random samples of Selar crumenophthalmus (bigeye scad) were collected from September 2012 to February 2013. The samples were caught from Bangaa faru, in Male’ atoll, Maldives. A total of 1648 samples were collected, with their fork length ranging from 7.7 cm to 24.5 cm (16.85 ± 2.82 cm) and body weight ranging between 8g to 255.6 g (87.76 ± 40.41g). FiSAT software was used in estimating the population parameters. The growth performance index in this study is estimated to be 2.818. Total mortality, natural mortality and fishing mortality were 4.01, 2.23 and 1.78 year-1 respectively. Length at first capture was estimated as 16.72 cm. The exploitation rate (E) is estimated as 0.56, which is higher than the optimum value of 0.5. Hence, the stock can be considered as over-exploited.
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ABSTRACT This study was carried out in Pedu Reservoir from July 2008 to August 2009. Seven sampling stations were designated (including riverine, transitional and lacustrine zone), and phytoplankton, with special emphasis on desmids and... more
ABSTRACT This study was carried out in Pedu Reservoir from July 2008 to August 2009. Seven sampling stations were designated (including riverine, transitional and lacustrine zone), and phytoplankton, with special emphasis on desmids and dinoflagellates spatial and temporal distribution were examined. Peridinium gatunense (Dinoflagellates) was the dominant species at Station 3 to Station 7. However, at Station 1 and Station 2, Tetraedron regulare and Cosmarium sp. (Desmids) was the dominant species, respectively. Spearmann Rank Correlation test showed correlation between phosphorus and species richness, thus support the ideas about phosphorus is the limiting factors of phytoplankton abundances in lake ecosystems.
Abstrak: Komposisi dan kelimpahan komuniti zooplankton di dalam dua sistem pengurusan air (kitar semula dan mengalir) di agroekosistem Muda telah dikaji selama dua musim penanaman padi pada tahun 2002–2003. Sejumlah 25 spesies rotifer, 19... more
Abstrak: Komposisi dan kelimpahan komuniti zooplankton di dalam dua sistem pengurusan air (kitar semula dan mengalir) di agroekosistem Muda telah dikaji selama dua musim penanaman padi pada tahun 2002–2003. Sejumlah 25 spesies rotifer, 19 spesies kladosera dan 2 spesies kopepoda telah berjaya dikenal pasti dalam kajian ini. Tidak ada perbezaan yang ketara bagi bilangan taksa zooplankton di antara dua sistem pengurusan air (kitar semula dan mengalir). Kelimpahan kumpulan kopepoda adalah dominan diikuti oleh kumpulan rotifera dan akhir sekali kladosera untuk kedua-dua plot yang dikaji. Spesies kladosera yang kerap direkodkan di kedua-dua sistem pengairan ini adalah Simocephalus latirostris dan Diaphanosoma sarsi manakala untuk rotifera ialah Asplanchna pridonta dan Platyias patulus. Abstract: The species composition and abundance of the zooplankton community from two types of irrigation water management system (recycled and uncontrolled flow) in the Muda agro-ecosystem, were studied o...
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A study on water quality of the two long-logged and abandoned headwaters in Temengor Reservoir was conducted to determine their natural recovery.In this study,we used National Water Quality Standards for Malaysia prepared by Malaysian... more
A study on water quality of the two long-logged and abandoned headwaters in Temengor Reservoir was conducted to determine their natural recovery.In this study,we used National Water Quality Standards for Malaysia prepared by Malaysian Department of Environment as an indicator for water quality recovery.The parameters measured were dissolved oxygen（mg/L）,water temperature（℃）,pH,conductivity（mS/cm）,total dissolved solids（mg/ L）,water velocity（m/s）,ortho-phosphate（PO4-P）,nitrite-nitrogen（NO2-N）,nitrate-nitrogen（NO3,-N）and alkalinity. In general,water quality in Sungai Enam and Sungai Telang were in ClassⅠ,indicating water quality in both streams have recovered.Based on the t-test,Sungai Enam and Sungai Telang differed significantly in all parameters except for dissolved oxygen,NO2-N and NO3-N.In spatial analyses（upper,middle and lower reaches comparisons）, the two-way ANOVA analysis shows that there were significant differences in all studied parameters between the two rivers except fo...
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Study on fish diversity and distribution in rice plots supplied with recycled and uncontrolled flow water was carried out from Season 1/2002 to Season II/2004 (August, 2002 to August, 2004) using a modified electroshocker. A total of 13... more
Study on fish diversity and distribution in rice plots supplied with recycled and uncontrolled flow water was carried out from Season 1/2002 to Season II/2004 (August, 2002 to August, 2004) using a modified electroshocker. A total of 13 species of fish were identified, with Cyprinidae being the dominant family in terms of the number caught (39.5%), followed by Aplocheilidae (18.2%), and Osphronemidae (12.0%). The number of species identified was lower as compared to those obtained in previous studies at selected irrigation canals in the Muda agro-ecosystem, and this due to different methodology employed. In the rice field plots irrigated by uncontrolled water flow, 13 species were recorded, whereas only 11 species were recorded in the plots irrigated by recycled water. However, based on the Shannon-Weiner Diversity and Evenness Indices, the values for the recycled water plots were higher (0.8764 and 0.8416, respectively) compared to the values obtained for the uncontrolled flow plot...
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The length-weight relationships of 12 freshwater fish species collected using various mesh size of gill nets and cast nets from Kerian River basin in Perak and Pedu Lake in Kedah were estimated. Devario regina, Rasbora sumatrana, Puntius... more
The length-weight relationships of 12 freshwater fish species collected using various mesh size of gill nets and cast nets from Kerian River basin in Perak and Pedu Lake in Kedah were estimated. Devario regina, Rasbora sumatrana, Puntius binotatus, Labiobarbus lineatus, Cyclocheilichthys apogon and Crossocheilus oblongus were caught from the Kerian River and its tributaries. Meanwhile in the Pedu Lake, there were Puntius schwanenfeldii, Notopterus notopterus, Chela sp., Mystacoleucus marginatus, Osteochilus microcephalus, and Puntius gonionotus. Fish total length (TL) and standard length (SL) and weight were recorded. The values of constants a and b were determined from the length and weight data which transform into the linear equation of lnW=lna+blnL. These parameters were then fitted to the parabolic equation, W=aL . The length-weight relationships of fish from both areas were significantly b different at P<0.001 and the growth exponents, b, for the fishes varied from 2.665 to...
A total of 22 species of zooplankton were identified from 8 sampling stations located in the limnetic zone of Pedu reservoir.The zooplankton community was dominated by rotifers (11 species),followed by cladocerans (9 species) and copepods... more
A total of 22 species of zooplankton were identified from 8 sampling stations located in the limnetic zone of Pedu reservoir.The zooplankton community was dominated by rotifers (11 species),followed by cladocerans (9 species) and copepods (2 species).Four species of zooplankton comprised of 3 rotifers,Brachionus quadridentata,Brachionus caudatus and Keratella cochlearis and one cladoceran,Ceriodaphnia cornuta were present at all sampling stations.Species richness was highest at Station 2 (17 species) followed by Station 4 and Station 8 (14 species),Station 5 (15 species),Station 7 (11 species),Station 6 (10 species),Station 3 (9 species) and Station 1 (7 species).With an exception of water transparency,all other water quality parameters such as temperature,dissolved oxygen,conductivity,pH and total dissolved solids were not significant when compared between sampling stations.The study found that station 5 which was located in a calm strait,protected from strong wave and wind was a s...
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A total of 37 fish species from 14 families were observed during surveys conducted from January to March 2005 at 8 selected streams near the Gunung Jerai Forest Reserve. The list includes two species (Rasbora trilineata and Systomus... more
A total of 37 fish species from 14 families were observed during surveys conducted from January to March 2005 at 8 selected streams near the Gunung Jerai Forest Reserve. The list includes two species (Rasbora trilineata and Systomus partipentazona) that were visually identified at the lower part of the Sungai Teroi stream. Single specimens of Leiocassis micropogon, Clarias macrocephalus and Hampala macrolepidota were also obtained at certain sampling stations. Devario regina and Systomus binotatus were the most abundant species at all sampling stations. However, the list is still incomplete as the study was carried out over a short time period and there are large areas that have not yet been surveyed. The presence of exotic species (Carassius auratus) at Sungai Badak indicates anthropogenic influences. Therefore, a long-term monitoring program for Gunung Jerai Forest Reserve streams should be planned and carried out to assess the impacts of future development on fish biodiversity an...
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Gracilaria red algae are notable for their economic importance as agrophytes, sold as salad vegetable, and used as the base for selected food and nonalcoholic beverages. A wild population of Gracilaria exists in coastal areas of Sarawak,... more
Gracilaria red algae are notable for their economic importance as agrophytes, sold as salad vegetable, and used as the base for selected food and nonalcoholic beverages. A wild population of Gracilaria exists in coastal areas of Sarawak, Malaysian Borneo, but there is only limited knowledge on species diversity and its abundance leaving the untapped economic potential of this resource. This study was carried out to determine diversity of wild Gracilaria populations in Lawas, Santubong, and Asajaya, Sarawak, using the combination of morphological character examination and 5′ region of the mitochondrial cytochrome c oxidase 1 (CO1-5P) gene analysis. Identification of the species using morphological characters revealed three species, namely, Gracilaria changii, G. blodgettii, and G. arcuata, had been collected from the sampling sites. However, based on 672 bp CO1-5P gene sequence analysis, all the three species were identified as G. blodgettii; besides, low genetic divergence values (0...
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Araceae family is the member of Order Arales. This family is best characterized by flowering plants, which have inflorescence in the spadix. Nowadays, Araceae becomes the most familiar plants to humans and also catogarized as an economic... more
Araceae family is the member of Order Arales. This family is best characterized by flowering plants, which have inflorescence in the spadix. Nowadays, Araceae becomes the most familiar plants to humans and also catogarized as an economic group. A large amount of Araceae has been largely planted, especially in Vietnam, a densely populated country. In Mekong Delta of Vietnam, the demands of using aroid species are increasingly popular. An investigation into use values of Araceae is conducted along Hau River, one of two largest branches of Mekong River in Vietnam. Households living along river banks are interviewed through questionnaires. From the result, there are 18 species of Araceae which role as decorative and ornamental plants such as Dieffenbachia maculata, Anthurium andreanum and Aglaonema nitidum. Another six species are cultivated as food plants for human as same as for feeding cattle, such as Alocasia, Colocasia and Xanthosoma. In medical field, 10 aroid species are used by ...
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An investigation study was conducted in Bukit Merah Reservoir (BMR) for the assessment of arsenic concentration in the surface sediment in 23 sampling stations. The sediment samples were digested and analysed for arsenic using Inductively... more
An investigation study was conducted in Bukit Merah Reservoir (BMR) for the assessment of arsenic concentration in the surface sediment in 23 sampling stations. The sediment samples were digested and analysed for arsenic using Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). Sediment parameters such as pH (4.42 ± 0.71), redox potential (121.77 ± 42.45 mV), conductivity (205.7 ± 64.07 μS cm–1) and organic matter (25.35 ± 9.34%) were also examined. The main objectives of this study are to determine the arsenic distribution and concentration and at the same time to assess the enrichment of arsenic using the geoaccumulation index (Igeo) and enrichment factor (EF). This study shows the total arsenic concentration in the surface sediment of BMR is 4.302 ± 2.43 mg kg–1 and found to be below the threshold value of Canadian Interim Sediment Quality Guidelines (ISQG). High arsenic concentration is recorded near the southern part of the lake where anthropogenic activities ar...
The nest is one of the crucial elements in orangutan daily activities. Previously, most of the nest structure studies were done manually by estimating measurement directly from visual observation. However, using the latest unmanned aerial... more
The nest is one of the crucial elements in orangutan daily activities. Previously, most of the nest structure studies were done manually by estimating measurement directly from visual observation. However, using the latest unmanned aerial vehicle (UAV) technology, we can reduce the workforce, time and energy while simultaneously ensuring the safety of the researcher conducting nest structure analysis. We recorded 49 pictures of orangutan nests at Sepilok Orangutan Rehabilitation Centre (SORC) using UAV (DJI Phantom 3 Quadcopter). The nest structure (length, depth, and width) was digitally measured by using ImageJ. Most of the nests were built at a strong, stable, and comfortable position at the top of the tree. Most orangutans chose Eusideroxylon zwageri to build nest compared to other tree species because of the strong and durable wood characteristic which would create a sturdy, strong and comfortable nest. We propose the use of drone with digital image analysis could provide a mor...
Although freshwater biomes cover less than 1% of the Earth&#39;s surface, they have disproportionate ecological significances. Attempts to study the taxonomy and function of freshwater microbiota are currently limited to samples... more
Although freshwater biomes cover less than 1% of the Earth&#39;s surface, they have disproportionate ecological significances. Attempts to study the taxonomy and function of freshwater microbiota are currently limited to samples collected from temperate lakes. In this study, we investigated samples from the photic and aphotic of an aquaculture site (disturbed) of Temengor Lake, a tropical lake in comparison with the undisturbed site of the lake using 16S rRNA amplicon and shotgun metagenomic approaches. Vertical changes in bacterial community composition and function of the Temengor Lake metagenomes were observed. The photic water layer of Temengor Lake was dominated by typical freshwater assemblages consisting of Proteobacteria, Actinobacteria, Bacteroidetes, Verrucomicrobia, and Cyanobacteria lineages. On the other hand, the aphotic water featured in addition to Proteobacteria, Bacteroidetes, Verrucomicrobia, and two more abundant bacterial phyla that are typically ubiquitous in anoxic habitats (Chloroflexi and Firmicutes). The aphotic zone of Temengor Lake exhibited genetic potential for nitrogen and sulfur metabolisms for which terminal electron acceptors other than oxygen are used in the reactions. The aphotic water of the disturbed site also showed an overrepresentation of genes associated with the metabolism of carbohydrates, likely driven by the enrichment of nutrient resulting from aquaculture activities at the site. The results presented in this study can serve as a basis for understanding the structure and functional capacity of the microbial communities in the photic and aphotic zones/water layers of tropical man-made lakes.