Sökning: "freshwater and marine ecology"
Visar resultat 11 - 15 av 129 avhandlingar innehållade orden freshwater and marine ecology.
11. The Spider and the Sea : Effects of marine subsidies on the role of spiders in terrestrial food webs
Sammanfattning : The purpose of this study was to identify if terrestrial arthropod predators on Baltic Sea shores vary in their use of marine versus terrestrial food items, and to construct a bottom-up food web for Baltic Sea shores. The inflow of marine nutrients in the area consists mainly of marine algal detritus and emerging aquatic insects (e.g. LÄS MER
12. Long-term studies of succession : Colonisation and seed banks
Sammanfattning : Using data from long-term studies of the vegetation in two areas under primary succession, patterns of colonisation and the accumulated seed bank during plant succession were studied.At century-old small islands in Lake Hjälmaren, Sweden, the genetic structure of differently old populations of Moehringia trinervia and Lythrum salicaria was studied, using allozyme variation for M. LÄS MER
13. Predators in low arctic tundra and their impact on community structure and dynamics
Sammanfattning : The abundance of predators and their impact on ecosystem dynamics is a vividly discussed topic in current ecology. In my studies, incorporating field observations, field experiments and theoretical modeling, I explored the importance of predators and predation in a low arctic tundra ecosystem in northern Norway. LÄS MER
14. Causes and consequences of quantitative trait variation for reproductive performance in hole nesting birds
Sammanfattning : This thesis examines the causes and consequences of environmental variability and individual morphological differences on breeding success and survival in three hole nesting birds.An analysis of directional and stabilising natural selection in Collared Flycatchers (Ficedula albicollis) suggested that forces of selection acting on quantitative traits are weak and cannot explain the observed sexual size dimorphism (SSD) in this species. LÄS MER
15. Ecology and control of Anopheles mosquitoes and human malaria in Guinea Bissau, West Africa
Sammanfattning : This thesis analyses the relationship between risk of exposure to infective Anophelesmosquitoes and different environmental factors, in particular house construction, presence ofdomestic animals and house location, in coastal Guinea Bissau, West Africa. The potentialeffect of permethrin-impregnated bed nets on mosquito abundance in bed rooms, and on thePlasmodium parasite prevalence in children was also analysed. LÄS MER