Ceylon Journal of Science (Biological Sciences)
Permanent URI for this collectionhttps://dl.nsf.gov.lk/handle/1/7565
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Item Composition, biomass and primary production of some grasslands in the Ruhuna National Park, Sri Lanka(1983) Chamber, M.R.; Balasubramaniam, S.; Santiapillai, C.; Ishwaran, N.Item Some ecological aspects of the mangroves on the west coast of Sri Lanka(1984-85) De Silva, K.H.G.M.; Balasubramaniam, S.Mangrove formation (mangals) on the west coast are not extensive and, in most places, are limited to narrow strips bordering river mouths and estuaries. A clear ecological zonation is difficult to discern, except for a Rhizophora-Bruguiera zone at the edge of the water followed by a zone containing the other core species. The low level of tidal amplitude as well as persistend and long-term human interference are major factors that led to the limitation of mangroves to narrow strips and to the disappearence or non-establishment of proper ecological zonation. Floristic composition of wet zone mangroves is somewhat different from that of dry zone mangroves. This difference appears to be due to prevailling salinity differences, wet zone mangroves experiencing lower salinity conditions and dry zone mangroves experiencing higher salinity conditions. In each zone, there are riverine and estuarine mangroves. Four types of high salinity (dry zone) estuarine mangroves, viz, fringing, scrub, overwash, and basin, could be distinguished depeding on the geomorphic and flooding characteristics. Basin mangroves are not found on the west coast. MAngroves in Sri Lanka have been subjected to man's detrimental interference to a greater or lesser degree for a long time. In the north-east, mangroves have received relatively less interference, but, those on the west and south-west coasts have been highly interfered with, and in some cases, mangroves have virtually disappeared. Urgent conservation measures are requaired to save Sri Lankan mangrovesItem Further observations on the mosquito fauna of Udawattakele forest, Sri Lanka(1984-85) Amerasinghe, F.P.; Munasinghe, N.B.A futher study of the mosquitoes at Udawattakele forest, Kandy was made during 1984-85, sampling the daytime resting, crepuscular-nocturnal human biting and light-trap attracted species, to suppliment information on the breeding and diurnal human biting species gatered during a previous study in 1980-81. Thirty species (7 genera) resting in the forest were collected using a battery powered suction sweeper, the dominant species being Culex psedovishnui. This species and Cx. nigropunctatus rested mainly on leaf litter on the forest or shrub/grass patches. Twenty five species (4 genera) were captured at human bait, with Armigeres subalbatus and Cx. pseudovishnui being the most prevalent. Biting rhythms associated with the evening crepaucular period were demonstrated in Aedes albopictus, Ar. subalbetus and Cx. psedovishoui, but not in Ae. chrysoscuta. Twenty five species (8 genera) were taken at CDC light traps with only Cx. pseudovishnui occurring in significant numbers. Overall, 61 species representing 11 genera have been recorded in Udawattakele Forest from all published sources. Species diversity indices as determined in the present study, however, were low and indicated the quantitative dominance of a few species in the forest in relation to the survey methods employedItem A refugium for Scaevola Plumieri, a highly threatened rare plant in Sri Lanka(University of Peradeniya. Peradeniya, 2005) Jayasuriya, A.H.M.Item Determination of different Juncus (Juncaceae) species occuring in Sri Lanka(University of Peradeniya. Peradeniya, 2005) Yakandawala, D.M.D.; Sirisena, U.M.; Dassanayake, M.D.