Sökning: "ecology art"
Visar resultat 1 - 5 av 78 avhandlingar innehållade orden ecology art.
1. Biodiversity in Agricultural Landscapes: Landscape and Scale-Dependent Effects of Organic Farming
Sammanfattning : Declines in the distribution and abundance of many farmland species during recent decades have been attributed to agricultural intensification. Agri-environment schemes are commonly used in Europe to reduce this loss of farmland biodiversity, but their effectiveness may depend on several external factors. LÄS MER
2. The Threat to the Baltic Salmon - a Combination of Persistent Pollutants, Parasite and Oxidative Stress
Sammanfattning : Atlantic salmon (Salmo salar) from the Baltic Sea suffer from a reproduction disease known as the M74-syndrome. Newly hatched fry develop nerve disorders and die between 3-5 days after the first symptoms are seen. This is a maternally transmitted disease that is casued by a thiamine (vitamin B1) deficiency. LÄS MER
3. Waterfowl herbivory on submerged macrophytes in eutrophic lakes
Sammanfattning : Submerged macrophytes are thought to stabilize clear-water states of shallow lakes. The aim of this thesis was to elucidate how waterfowl herbivory can affect abundance, distribution and species composition of submerged macrophytes in eutrophic lakes. LÄS MER
4. Species interactions govern evolutionary and ecological effects of population harvesting
Sammanfattning : Harvesting changes population abundance and can affect adaptation of several life-history traits. Harvesting can also have indirect effects ? effects on non-target species and secondary effects on target species ? because interactions between species in a community determine the relevant ecological and evolutionary feedback environment. LÄS MER
5. Geographic Variation, Hybridization and Evolution in the Bladder Campions, Silene vulgaris and S. uniflora (Caryophyllaceae)
Sammanfattning : In the present thesis, I investigated the inter- and intraspecific variation in the Silene vulgaris/uniflora species-complex (the bladder campions). I have focused on the effects of past and present hybridization both on a large scale ? over the whole of Europe ? and on a local scale. Silene vulgaris and S. LÄS MER