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Ecological surveys were carried out to investigate the distribution and characterization of riparian corridor plants along the Perai River,Penang,Malaysia from July 2007 to March 2008.Surveys were design to represent horizon-tal sections of the river starting from the river mouth towards the upper reaches for 20 km.A total of 84 species of plants from 30 families were recorded.They consisted of 28 species of standing plants(plants with height of more than 1 m)and 56 species of weedy plants(plants with height of less than 1 m).Standing plants consisted of ferns,palms,herbs,shrubs and mangroves while weedy plants comprised of aroids,grasses,sedges and broad leaf weed.Species abundance and dominance for each zone were relatively different.Dominant species was determined using Important Species Index(ISI).Based on ISI,the important species of standing plants were Sonneratia alba,Acrostichum aureum,Nypa fruti-cans,Avicennia marina,Rhizophora apiculata,Acrostichum speciosum and Rhizophora mucronata.Weedy plants were dominated by Mikania micrantha,Cryptocoryne ciliata,Wedelia trilobata and Asystasia intrusa.The distribution of the corridor plant species was closely related to the pattern of river water salinity measurements.The distribution of mangrove species with tolerance and adaptation to seawater appeared as follows:Avicennia marina,Rhizophora apiculata,Rhizo-phora mucronata,Sonneratia alba,Nypa fructicans,Acrostichum aureum and Acrostichum speciosum.

Oviposition preferences of three major identified parasitoids; Ooencyrtus erionotae Ferrière (Hymenoptera, Encyrtidae), Cotesia erionotae (Wilkinson) (Hymenoptera, Braconidae) and Brachymeria albotibialis (Ashmead) (Hymenoptera, Chalcididae) of Erionota thrax (L.) (Lepidoptera: Hersperiidae) eggs, larvae and pupae respectively were studied in the laboratory and field during a high-density period of the pest. Egg stage I (newly laid), stage 2 (intermediate), and stage 3 (advanced) were susceptible to O. erionotae oviposition. Stage 3 was the most preferred egg host with a mean of 3.4 adult parasitoids emerging per egg. For C. erionotae, second, third, and fourth larval instars were susceptible. The third instar larva was the most preferred stage for oviposition with a mean of 87 adult parasitoids emerging per larva. For B. albotibialis, only prepupae and pupae were susceptible. The pupa was the most preferred host stage with mean of 7.1 adult parasitoids emerging per pupa. In the case of O. erionotae and C. erionotae, no super-parasitism or multi-parasitism was observed.

Putrajaya Wetlands in Malaysia, a 200 ha constructed wetland system consisting of 24 cells, was created in 1997–1998 to treat surface runoff caused by development and agricultural activities from an upstream catchment before entering Putrajaya Lake (400 ha). It was designed for stormwater treatment, flood control and amenity use. The water quality improvement performance of a section of the wetland cells is described. The nutrient removal performance was 82.11% for total nitrogen, 70.73% for nitrate–nitrogen and 84.32% for phosphate, respectively, along six wetland cells from Upper North UN6 to UN1 from April to December 2004. Nutrient removal in pilot scale tank systems, simulating a constructed wetland and planted with examples of common species at Putrajaya, the Common Reed Phragmites karka and Tube Sedge Lepironia articulata, and the capacity of these species to retain nutrients in above and below-ground plant biomass and substrate is reported. The uptake of nutrients by the Common Reed and Tube Sedge from the pilot tank system was 42.1% TKN; 28.9% P and 17.4% TKN; 26.1% P, respectively. The nutrient uptake efficiency of the Common Reed was higher in above-ground than in below-ground tissue. The results have implications for plant species selection in the design of constructed wetlands in Malaysia and for optimizing the performance of these systems.

Oviposition preferences of three major identified parasitoids; Ooencyrtus erionotae Ferrière (Hymenoptera, Encyrtidae), Cotesia erionotae (Wilkinson) (Hymenoptera, Braconidae) and Brachymeria albotibialis (Ashmead) (Hymenoptera, Chalcididae) of Erionota thrax (L.) (Lepidoptera: Hersperiidae) eggs, larvae and pupae respectively were studied in the laboratory and field during a high-density period of the pest. Egg stage I (newly laid), stage 2 (intermediate), and stage 3 (advanced) were susceptible to O. erionotae oviposition. Stage 3 was the most preferred egg host with a mean of 3.4 adult parasitoids emerging per egg. For C. erionotae, second, third, and fourth larval instars were susceptible. The third instar larva was the most preferred stage for oviposition with a mean of 87 adult parasitoids emerging per larva. For B. albotibialis, only prepupae and pupae were susceptible. The pupa was the most preferred host stage with mean of 7.1 adult parasitoids emerging per pupa. In the case of O. erionotae and C. erionotae, no super-parasitism or multi-parasitism was observed.

A preliminary study on the fish community in two rural lakes in Bumbung Lima, Kepala Balas was conducted from May 2003 to November 2003. Species abundance and composition were affected by various factors such as water quality, encroaching of aquatic vegetation and human activities at the study sites. A total of 28 fish species from 10 families were recorded during the study period. Cyprinidae was the dominant family while Puntius schwanenfeldii and P. gonionotus were the most widespread species identified. Socioeconomic studies which include human activities in Bumbung Lima area were reviewed. Field survey using questionnaires have been carried out in an attempt to obtain information on socio-demographic status of the study sites. Results showed that over one-third of the heads of households in Bumbung Lima depended on agriculture for their living which was 36.25% followed by 27.5% were government servants. In terms of education, majority of respondents received their level of education only until secondary school, which was accounted for 50% of overall education. Regarding monthly income, about one-third of the respondent earned below than RM 400 per month (33.75%). Only 18.75% of the respondents obtained a salary above RM 1000 per month, which was comparatively small and thus form only a minor portion of total respondents.

A survey of the distribution of weeds was carried out in two rural lakes in Bumbung Lima, Kepala Batas, Pulau Pinang. A total of 36 taxa representing to 22 families have so far been identified. The results showed that Gramineae notably Phragmites communis was dominant at the sampling station followed by Scirpus grossus and Polygonum barbatum. The vegetation of weed species in the area was studied primarily towards identifying of plant species present and their distribution. The objectives of this study are to describe the species composition and diversity of weed species around the lakes.

The aroids are monocotyledonous herbaceous plants, which are widely found in tropical countries. This Araceae family has played an important role not only in botanical world but also in economical aspects such as by providing medicinal resources. The medicinal properties, which proved to have a curative effect on certain diseases, indicate that these species have a potential value in medicinal industries.

The aroid family or also known as Araceae, is generally a tropical plant, however some of the species are distributed worldwide. This family is grouped into nine subfamilies, 106 genera and 3200 species.

The Ayer Hitam Forest Reserve has possibly been under constant threat from invasive species especially the weeds from surrounding development sites. The total number of weed taxa identified from this forest were 33 species, 29 genera and J3 families. Of these taxa, only two species aquatic weeds vizs., Ceratopteris thalictroides (Parkeriaceae) and Hydrilla venieillata (Hydrocharitaceae). The most dominant terrestrial weedy speeies in this forest were Clidemia hirta (Melastomataceae) and Chromalaena odorata (Compositae). All grasses and sedges !lIJi~si,~s were recorded at the disturbed sampling sites only. Limosa pigra was only found at the most disturbed site bordering the forest.