Sökning: "Freshwater ecology"
Visar resultat 1 - 5 av 178 avhandlingar innehållade orden Freshwater ecology.
Sammanfattning : Cross-boundary movements of energy and material are ubiquitous. Freshwater ecosystems receive nutrients, dissolved, and particulate organic matter from adjacent terrestrial ecosystems, whereas terrestrial ecosystems mainly receive prey organisms and detritus deposited by physical processes such as floods from freshwater ecosystems. LÄS MER
2. Evolutionary ecology of arctic char (Salvelinus alpinus (L.)) : Intra- and interspecific interactions in circumpolar populations
Sammanfattning : This thesis examines a suite of ecological and genetic mechanisms influencing the fundamental and realized niche borders of European and North American populations of the Arctic char (Salvelinus alpinus (L.)) species complex in allopatry as well as in sympatry with brown trout (Salmo trutta) or brook trout (Salvelinus fontinalis). LÄS MER
Sammanfattning : For many years, the importance of microorganisms attached to surfaces in littoral zones and wetlands has been disregarded when describing aquatic ecosystem dynamics. Supporting evidence is scarce but convincing that these microbial communities are not only very productive but can often serve as major regulators of nutrient and carbon dynamics in many freshwaters. LÄS MER
Sammanfattning : This thesis investigates ecological and evolutionary mechanisms behind the variation in male mating behaviour in fallow deer (Dama dama) populations. Two Swedish populations of fallow deer were studied, a semi-wild enclosed population on the island of Öland in the Baltic Sea (Ottenby), and a deer farm located north of Uppsala (Bälinge). LÄS MER
5. Variation in Pseudorchis albida s.l. (Orchidaceae) and Carex capitata s.l. (Cyperaceae) : Morphology, genetic diversity, ecology and systematics
Sammanfattning : In the Scandinavian flora, several species-pairs where one member is an alpine species andthe other is a closely related lowland species, have been described. The aim of this studywas to investigate two such examples, viz. Pseudorchis albida s.s. LÄS MER