Sökning: "ecology"
Visar resultat 41 - 45 av 1824 avhandlingar innehållade ordet ecology.
41. Viruses on the wing : evolution and dynamics of influenza A virus in the Mallard reservoir
Sammanfattning : This thesis explores the evolution of avian influenza A viruses (IAV), as well as host-pathogen interactions between these viruses and their main reservoir host, the Mallard (Anas platyrhynchos). IAV is a genetically diverse, multi-host virus and wild birds, particularly dabbling ducks, are the natural reservoir. LÄS MER
42. Insect Diversity in Changing Landscapes
Sammanfattning : During recent decades, concern about the loss of biodiversity has increased. To change this negative trend there is an urgent need for effective conservation measures and there are ample evidence that conservation of organisms without an understanding of their ecology and behaviour is impossible. LÄS MER
43. Direct and indirect effects of fish predation and excretion in aquatic food webs
Sammanfattning : The aim of this thesis was to elucidate the mechanisms by which planktivorous fish can affect planktonic communities in lakes and how they may affect benthic communities through their effects on planktonic communities. In a laboratory experiment, nutrients released by fish increased algal biomass and altered phytoplankton community structure, suggesting that fish can affect phytoplankton by directly releasing nutrients. LÄS MER
44. On enchytraeids and naidids: Life history traits and responses to environmental stress
Sammanfattning : My thesis shows that enchytraeids and naidids are sensitive to various forms of environmental stress, which in combination with the wide distribution of both families make them highly suitable for use in risk assessment and soil monitoring. Enchytraeids were subject to chemical stress under both laboratory and field conditions. LÄS MER
45. Limitations and possibilities for microbial degradation of organic contaminants in aquifers
Sammanfattning : Many factors can influence the rate of microbial degradation of organic contaminants in aquifers. Some of these factors, e.g. LÄS MER