Sökning: "environmental cues"
Visar resultat 1 - 5 av 75 avhandlingar innehållade orden environmental cues.
1. Ecology of zooplankton communities: climate, dormancy, and benthic-pelagic coupling
Sammanfattning : This thesis describes how influences, such as top down and bottom up forces, shape zooplankton communities in shallow lakes. I have also extended the traditional food-web theory by investigating the effects of climate on total biomass, taxonomic composition, and temporal properties of zooplankton communities. LÄS MER
2. Structuring factors for macroinvertebrate communities and the importance for ecosystem processing
Sammanfattning : Aquatic macroinvertebrates play important roles in our ecosystems and are essential for the ecosystem processing. An improved knowledge of structuring factors, such as competition and predation, and the way in which they operates in the macroinvertebrate community is crucial for our understanding of not only the macroinvertebrates but also the ecosystem in general. LÄS MER
3. Local adaptive pigmentation in Asellus aquaticus -effects of UV-radiation and predation regime
Sammanfattning : Pigmentation in the freshwater isopod Asellus aquaticus differed between two habitats. Asellus were lighter pigmented in stands of submerged stonewort vegetation, than in nearby reed stands. Moreover, Asellus pigmentation became lighter with time in recently established stonewort stands. LÄS MER
4. The importance of predation in benthic stream communities
Sammanfattning : There has been considerable debate whether or not predators has any significant effects on prey densities in streams. This thesis examines the importance of predation in stream communities. I have conducted both field and laboratory studies where I have studied how both vertebrate and invertebrate predators affects benthic prey. LÄS MER
5. Zooplankton responses to threats from UV and predation
Sammanfattning : Ultraviolet radiation (UV) has been present longer than any biological life, and during the development of life the radiation intensities were initially high. Eventually a vital ozone layer developed, but despite that this layer screens out most of the high energy wavelengths, some still enter the biosphere and is potentially harmful to life on earth. LÄS MER