Sökning: "trophic effects"
Visar resultat 6 - 10 av 148 avhandlingar innehållade orden trophic effects.
6. Organic Phosphorus Compounds in Aquatic Sediments : Analysis, Abundance and Effects
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
7. Ontogenetic bottlenecks : effects on intraguild predation systems and ecosystem efficiency
Sammanfattning : Size-dependent differences between individuals in size-structured organisms have fundamental effect on population and community dynamics. Intraguild predation (IGP) is one specifically interesting constellation that often arises when two size-structured populations interact. LÄS MER
8. Fish on drugs : behaviour modifying contaminants in aquatic ecosystems
Sammanfattning : Contamination of surface waters is a worldwide problem. One group of emerging contaminants that reach aquatic ecosystems via sewage treatment plant effluents and agricultural run-offs is pharmaceuticals. LÄS MER
9. Regulation of digestive organ. An experimental study on the role of CCK, Bile and EGF
Sammanfattning : Cholecystokinin (CCK) is known to exert secretory and trophic effects on the pancreas. Its release from the intestinal mucosa is regulated by pancresic proteases in the small intestine. However, knowledge about the type of responding exocrine cells and the time course of events during stimulation with CCK is lacking. LÄS MER
10. Role of ecological processes in determining effects of contaminants in aquatic ecosystems
Sammanfattning : Aquatic ecosystems cover approximately 70% of the Earth’s surface and support a wide range of ecosystem services. Despite their importance, aquatic ecosystems are increasingly exposed to anthropogenic stressors, such as contaminants and climate change impacts. LÄS MER