Sökning: "akvatisk ekologi"
Visar resultat 1 - 5 av 98 avhandlingar innehållade orden akvatisk ekologi.
1. Predator-prey interactions in freshwater systems: The importance of chemical communication
Sammanfattning : Predator released chemical cues provide a valuable source of information to prey organisms that can be used to alter their behaviour in order to reduce predation risk. In this thesis, I have examined under what circumstances chemical cues may be used by prey, and if prey discriminate between different cues. LÄS MER
2. Foraging behaviour in benthivorous fish
Sammanfattning : The foraging ability of an organism is essential since it affects various traits, e.g. growth, reproduction effort, social status and, ultimately, fitness. LÄS MER
3. 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
4. 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
5. The importance of terrestrial carbon in plankton food webs
Sammanfattning : Allochthonous substances, i.e. produced in terrestrial ecosystems, are known to fuel bacterial production in humic lakes. I observed that allochthonous carbon subsidizes bacteria even at high levels of phytoplankton biomass. LÄS MER