Sökning: "trophic effects"
Visar resultat 1 - 5 av 137 avhandlingar innehållade orden trophic effects.
Sammanfattning : This thesis examines how freshwater crayfish affect community interactions in benthic food webs. I have mainly studied the influence of the introduced signal crayfish (Pacifastacus leniusculus) on littoral communities, but also the influence of the native noble crayfish (Astacus astacus). LÄS MER
Sammanfattning : According to the United Nations, plastic pollution in the natural environment has been identified as one of the biggest environmental challenges of this century and has become a cause for an emerging international concern. It has been predicted that up to 12 million tons of plastic waste reach the aquatic environment annually. LÄS MER
3. Trophic ecology of meiofauna : Response to sedimentation of phytoplankton blooms in the Baltic Sea
Sammanfattning : Marine soft sediments are the second largest habitat on Earth. How animal communities in this habitat are structured is a central issue in marine ecology. Food is an important limiting factor for many benthic populations, and settling organic matter from phytoplankton blooms is of vital importance to them. LÄS MER
4. The Role of CCK-A and CCK-B Receptors in the Trophic Control of Pancreas and Oxyntic Mucosa in the Rat
Sammanfattning : Cholecystokinin (CCK) and the related hormone gastrin have been claimed to exert trophic effects in the pancreas and gastrointestinal tract. Two types of receptors for CCK and gastrin are known to exist, the CCK-A and the CCK-B receptor. They differ in their affinty for CCK and gastrin. LÄS MER
Sammanfattning : Phosphorus (P) is often the limiting nutrient in lacustrine and brackish eco-systems, and enhanced input of P into an aquatic system might therefore negatively impact the environment. Because modern waste water manage-ment have reduced external P input to surface waters, internal P loading from the sediment has become one of the main P sources to aquatic ecosys-tems, in which relatively unknown organic P compounds seem to be more active in P recycling than previously thought. LÄS MER