Search for dissertations about: "Water hyacinth"

Found 4 swedish dissertations containing the words Water hyacinth.

  2. 1. Essays on the Infestation of Lake Victoria by the Water Hyacinth

    Author : Eseza Kateregga; Göteborgs universitet; []
    Keywords : SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Water hyacinth; water hyacinth indicators; water hyacinth induced catchability coefficients; intrinsic growth rates for stocks; carrying capacity; elasticity of catch with respect to fishing effort; electricity outage costs.;

    Abstract : This thesis consists of four essays that seek to estimate the abundance of the water hyacinth in Lake Victoria during the 1990s and analyse its effects on the catchability of fish, estimate the elasticities of catch with respect to the various components of effort in lake Victoria fisheries, and estimate the welfare costs of electricity outages. In the first essay, data on the extent of water hyacinth mat coverage collected from a number of reports and surveys is used to fit time trend water hyacinth mats growth curves for the three sections of Lake Victoria. READ MORE

  4. 2. How elephants utilize a miombo-wetland ecosystem in Ugalla landscape, Western Tanzania

    Author : Elikana Kalumanga; Sara Cousins; Steve Lyon; Jan Bengtsson; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Biodiversity; Browsing; Elephants; Forage; GPS collars; Mineral elements; Miombo woodlands; Protected areas; Termite mounds; Ugalla; Water hyacinth; Woody plants abundance; Physical Geography; naturgeografi;

    Abstract : African elephants are ‘keystone’ species with respect to biodiversity conservation in Africa since they maintain habitats that support several animal communities by changing vegetation structure through foraging and by dispersing seeds between landscapes. Elephants are also ‘flagship’ species because, given their impressive size, they can make people sympathetic and stimulate local and international concerns for their protection. READ MORE

  5. 3. Water hyacinth (Eichhornia crassipes) : biomass production, ensilability and feeding value to growing cattle

    Author : Ho Thanh Tham; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Keywords : LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Abstract : Water hyacinth has now spread to all tropical and subtropical countries and is regarded as one of the world's most invasive aquatic plants. Water hyacinth (WH) is also known to have significant ecological and socio-economic effects. READ MORE

  6. 4. Nutrient utilisation in growing Cambodian cattle : effect of different feed sources and feed conservation techniques

    Author : Keo Sath; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Keywords : LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Abstract : Natural forages are an important part of the diet of cattle in Cambodia, but their nutrient value, particularly in terms of macro-minerals, may be inadequate, leading to potential mineral deficiencies in grazing cattle. This thesis compared the nutrient composition of six forage types (rice bran, rice straw, para grass, cassava foliage, leucaena leaves, water hyacinth leaves) from two regions in Cambodia against faecal and urinary excretion of macro minerals by cattle. READ MORE