Sökning: "freshwater production"
Visar resultat 1 - 5 av 71 avhandlingar innehållade orden freshwater production.
1. Land Use, Freshwater Flows and Ecosystem Services in an Era of Global Change
Sammanfattning : The purpose of this thesis is to analyse interactions between freshwater flows, terrestrial ecosystems and human well-being. Freshwater management and policy has mainly focused on the liquid water part (surface and ground water run off) of the hydrological cycle including aquatic ecosystems. LÄS MER
2. Carbon metabolism in clear-water and brown-water lakes
Sammanfattning : The trophic state of lakes is commonly defined by the concentration of nutrients in the water column. High nutrient concentrations generate high phytoplankton production, and lakes with low nutrient concentrations are considered low-productive. LÄS MER
3. Factors controlling pelagic communities of freshwater ciliates and heliozoans
Sammanfattning : Ciliate diversity and seasonal succession were studied during two years in oligotrophic,acidic Lake Njupfatet. Maximum ciliate abundance occurred shortly after ice-out. After thefirst year, the lake was neutralised by liming. Liming caused changes in the bacterioplanktonand phytoplankton communities, but no change in ciliate diversity. LÄS MER
4. Global trade, food production and ecosystem support : Making the interactions visible
Sammanfattning : Modern food production is a complex, globalized system in which what we eat and how it is produced are increasingly disconnected. This thesis examines some of the ways in which global trade has changed the mix of inputs to food and feed, and how this affects food security and our perceptions of sustainability. LÄS MER
5. Attached Bacterial Communities in Lakes – Habitat-Specific Differences
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
