Mashhor Mansor

Aquatic pollution assessment based on attached diatom communities in the Pinang River Basin, Malaysia

The diatom communities collected from artificial substrates (glass slides) at 12 sampling sites along Pinang River Basin were analysed. Species composition was highly variable among sampling sites, and the highest diversity value (mean H′ = 3.56 bit/individual) and species richness (mean S = 17.32) was recorded at a polluted station in an estuary, which received salt-water intrusion during high tide. The downstream sampling stations were heavily organically polluted with Saprobic Index values ranging between 2.81 and 3.10, while upstream stations were relatively clean with Saprobic Index values recorded between 1.40 and 1.96. The diatom community structure and the specific sensitivity of certain diatom species can be related to the degree of water quality in Pinang River Basin. The abundance of certain diatom species could be used as biological indicators to measure impacts of river pollution.

Noxious floating weeds of Malaysia

After ten years of field surveys on various water bodies ranging from stagnant water ponds, pools and man-made lakes to flowing waters such as rivers, streams and canals, there is a clear evidence of four problematic weeds in Malaysia. These species are Eichhornia crassipes, Salvinia molesta, Lemna perpusilla, and Pistia stratiotes. Among these weeds, E. crassipes and S. molesta are widely distributed througout Malaysia. E. crassipes generally dominates canals and rivers although, recently, this species has spread to man-made lakes. The favourable tropical climate and conducive environmental factors help to trigger the massive growth of these weeds. The high nutrient concentrations, notably phosphate which has a soluble reactive concentration greater than 0.1 mg 1–1, initiate a high productivity. Manual control methods are generally used and several herbicides including 2,4-D and glyphosate are frequently employed to eradicate these weeds.

Spatial distribution of banana skipper (Erionota thrax L.) (Lepidoptera: Hesperiidae) and its parasitoids in a Cavendish banana plantation, Penang, Malaysia

Abstract Spatial distribution of immatures of the banana skipper (Erionota thrax L.) and their parasitisms from three major parasitoids were studied in a Cavendish banana plantation from April 2004 to December 2004. Infestation levels and parasitism of E. thrax life stages were recorded from bunched plants (BP), flowering plants (FP), preflowered plants (PF), broad leaf followers (BLF) and narrow leaf followers (NLF), as well as on well managed and poorly managed plants. Mean numbers of the immatures and numbers parasitized from the nine blocks in the plantation were fitted to four dispersion indices. Significant numbers of E. thrax immatures and those parasitized by Ooencyrtus erionotae, Cotesia erionotae and Brachymeria albotibialis were recorded from BLF and PF; no eggs were found on BP and FP. Although infestation was higher on well managed plants, only larval parasitism was significantly different. Three of the four indices indicated that eggs and larvae were random while all the indices showed pupae to be clumped. Parasitized eggs and pupae were clumped (4/4 indices) while 3/4 indices revealed a random pattern for parasitized larvae.

Cryptocoryne elliptica, an endangered amphibious plant in Pondok Tanjung forest reserve, Peninsular Malaysia

Abstract Crytocoryne elliptica Hook. f. is an endangered plant species endemic to Peninsular Malaysia. The species thrives in swampy and shaded habitats. In its natural habitat, Pondok Tanjung Forest Reserve, this plant coexists with other plants such as Cryptocoryne purpurea Ridl. and homalomena nutans Hook. f. High population densities were observed where the depth of the water was not more than 0.5 m, the pH values ranged between 4.50 and 6.65, conductivity ranged from 7.0 to 10.4 μS cm −1 and dissolved oxygen concentrations and redox potential were relatively low. On the other hand, the habitat had a comparatively high concentration of soluble reactive phosphate and a high percentage of organic matter in the sediment.

A low cost approach of multisensor device for global warming studies

Global warming is an issue that keeps coming up recently with the increase of temperature and carbon dioxide level. Scientist believes that the main cause of this is because of the deforestation, pollution, carbon emission from transportation and factories that led to this global warming. However, there are also skeptics that believe otherwise. To prove the cause of global warming and whether it is an event that occurs every now and then as some skeptics and scientists suggested a multi sensor device is build, which consist of temperature, humidity, carbon dioxide and oxygen. With limited funding and a few different location to be tested to prove this phenomena, a low cost device is built so that it will be within the budget of this project as well give the result that is to determine whether development has cause the global warming and forest and absorbing the CO2 emission to keep the world cool. Thanks to open source hardware, the sensor system can be build economically.

Seasonal abundance of the banana skipper, Erionota thrax (Lepidoptera: Hesperiidae) and its parasitoids in a commercial plantation and a subsistence farm in Penang, Malaysia

To characterize the population dynamics of Erionota thrax Linnaeus and its major parasitoids, biweekly samplings were carried out in a commercial Cavendish banana plantation and a subsistence farm of local varieties, from April 2004 to November 2005. Five primary endoparasitoids were recorded: Ooencyrtus erionotae Ferriere, Cotesia erionotae Wilkinson, Brachymeria albotibialis Hoffmann, Elasmus sp. and Melaloncha sp. Ooencyrtus erionotae, C. erionotae, and B. albotibialis were, respectively, the major egg, larval and pupal parasitoids. In 2004, there was no significant difference in the E. thrax population densities and parasitism of immature life stages in both farms. In 2005, the pest population densities were significantly different, while only egg and larvae parasitism rates were significantly different. In the commercial plantation, peaks of E. thrax population densities per banana mat were recorded in April, June, July, and October–December and highest values for eggs, larvae and pupae were 4.66, 2.76 and 1.7, respectively. Percentage parasitism peaked in August, October, and February with peak values ranging from 60 to 100%. In the subsistence farm, peak E. thrax population densities were observed between May–July and September–December. Percentage parasitism peaked in January, February, July, August, October and November, with peak values ranging from 24 to 100%. Correlations between population densities of E. thrax and the numbers of parasitized insects showed strong positive relationships. There was evidence of a delayed density dependence of the parasitoids as most peaks of parasitism appeared 1 or 2 months after those of the host stages. Parasitism rates in the commercial plantation were substantial in spite of the frequent use of insecticides, and activities of the parasitoids were more favoured in the subsistence farm compared with the commercial plantation.RésuméUn échantillonnage a été réalisé toutes les deux semaines, d’avril 2004 à novembre 2005, dans une plantation industrielle de bananiers de la variété Cavendish et dans une plantation artisanale de bananiers locaux, afin de suivre la dynamique des populations d’Erionota thrax Linnaeus et de ses principaux parasitoïdes. Nous avons trouvé cinq espèces d’endoparasitoïdes primaires: Ooencyrtus erionotae Ferriere, Cotesia erionotae Wilkinson, Brachymeria albotibialis Hoffmann, Elasmus sp., et Melaloncha sp. Ooencyrtus erionotae, C. erionotae et B. albotibialis sont respectivement les plus importants parasitoïdes des oeufs, des chenilles et des chrysalides. En 2004, les densités de population d’E. thrax et les taux de parasitisme larvaire n’étaient pas significativement différents entre les deux fermes. En 2005, les densités de populations étaient significativement différentes et seuls les taux de parasitismes des oeufs et des larves étaient différents. Dans la plantation industrielle, les pics de densité de population par pseudotige ont été enregistrés en avril, juin, juillet et octobre–décembre avec des valeurs maximales d’oeufs, de chenilles et de chrysalides de 4,66, 2,76 et 1,7 respectivement. Les plus forts taux de parasitisme ont été enregistrés en aoû t, octobre et février avec des valeurs maximales comprises entre 60 et 100%. Dans la ferme artisanale, les pics de densité d’E. thrax ont été observés entre mai–juillet et septembre–décembre et les pics de parasitisme en janvier février, juillet, aoû t octobre et novembre avec des valeurs maximales comprises entre 24 et 100%. Une forte corrélation positive a été établie entre les densités de population d’E. thrax et le nombre d’insectes parasités. On a pu montrer l’existence d’une relation de densité dépendance du parasitisme, avec un décalage de 2 mois, entre les pics du ravageur et des parasitoïdes. Dans la plantation industrielle, les taux de parasitisme étaient importants malgré l’épandage fréquent d’insecticides. Toutefois, l’action des parasitoïdes était plus efficace dans la plantation artisanale que dans la plantation industrielle.

Fish checklist of Perak River, Malaysia

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.

Floristic diversity, composition, and environmental correlates on the arid, Coralline Islands of the Farasan Archipelago, Red Sea, Saudi Arabia.

Urban expansion and the associated increase in anthropogenic pressures have led to a great loss of the Red Seas biodiversity. Floristic composition, diversity, and environmental controls were investigated for 210 relevés on twenty coral islands of Farasan in the Red Sea, Saudi Arabia. Multivariate statistical analyses for classification (Cluster Analysis), ordination (Detrended Correspondence Analysis (DCA), and Redundancy Analysis (RDA) were employed to identify vegetation types and their relevance to the underlying environmental gradients. A total of 191 flowering plants belonging to 53 families and 129 genera were recorded. Geophytes and chamaephytes were the main life forms in the saline habitats, whereas therophytes and hemicryptophytes dominated the sandy formations and coral rocks. The cluster analysis and DCA ordination identified twelve vegetation groups that linked to five main habitats with definite floristic composition and environmental characteristics. The constrained RDA with Monte Carlo permutation tests revealed that elevation and soil salinity were the main environmental factors explaining the vegetation distributions. These results indicate that the flora of the study archipelago represents a phytogeographical linkage between Africa and Saharo-Arabian landscape functional elements. These findings should guide conservation and management efforts to maintain species diversity, which is threatened by anthropogenic activities and invasion by the exotic invasive tree Prosopis juliflora (Sw.) DC.

Development of prototype system for monitoring and computing greenhouse gases with Unmanned Aerial Vehicle (UAV) deployment

This paper presents the development of prototype system for monitoring and computing greenhouse gases (GHG) with Unmanned Aerial Vehicle (UAV) deployment for collecting data for different nodes. This system is based on wireless ZigBee technology that transfers the data wirelessly to UAV, which function is as a router, from which data is sent again to a data logger. An ATMEGA328P microcontroller is used to compute parameters such as CO2, O2, temperature and humidity. All the environmental parameters are measured on real time and are being stored in Secured Digital (SD) card for every 30 seconds interval. The data is collected at Engineering Campus, Universiti Sains Malaysia in Nibong Tebal, Pulau Pinang, Malaysia using UAV at several nodes. The results show that the system is able to trace and record CO2, O2, temperature and humidity level, which are important parameters for studies related to global warming.

The flora composition of Sabang Island, Aceh, Indonesia

We provide a checklist of Angiosperms from a rapid flora inventory of Sabang Island, Aceh, Indonesia. This inventory, conducted in April 2010, was carried out to prepare a baseline data of the floral composition in the north-western island archipelago of Aceh. In this exercise, we covered a total of 7 plots (0.2 ha each) and 120 quadrats (1x1 m each) in 7 sampling locations within the island. In total, we recorded 325 species from 211 genera of 68 families. Nine predominant families (i.e. family with ≥ 10 species) are Euphorbiaceae (32 species), Cyperaceae (19 species), Fabaceae (17 species), Moraceae (15 species), Meliaceae (13 species), Lauraceae and Sterculiaceae (12 species, respectively), Rubiaceae (11 species) and Annonaceae (10 species). The volcanic soil of the island could have played a significant role in defining species composition and their abundance. On the non-woody species’ composition and abundance, the increasing magnitude of anthropogenic activities, for example, road and pathways constructions into the forested area, could have enhanced propagule dispersal of non-native plants into the area.