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Visar resultat 1 - 5 av 51 avhandlingar som matchar ovanstående sökkriterier.
1. Biogeochemistry in Subarctic birch forests : Perspectives on insect herbivory
Sammanfattning : Herbivory can influence ecosystem processes, partly through long-term changes of the plant community compositions, but also more rapidly through the herbivores’ digestive alteration of the organic matter that is cycled through the soil and back to the primary producers. In the Subarctic mountain birch (Betula pubescens ssp. LÄS MER
2. Drivers of increasing iron concentrations in freshwaters
Sammanfattning : Iron (Fe) concentrations are increasing in freshwaters (lakes and streams) in Sweden, as well as in other regions in northern Europe. Together with increasing concentrations of organic matter, Fe is contributing to the ongoing browning of freshwaters, which may have serious ecological consequences and implications for ecosystem services. LÄS MER
3. Northern peatland carbon biogeochemistry : the influence of vascular plants and edaphic factors on carbon dioxide and methane exchange
Sammanfattning : The interest in carbon dynamics and the interactions between ecosystems and the atmosphere has increased during the last decade due to the postulated threat of anthropgenically induced global and climate change. Northern peatlands, with their large stores of organic carbon and long-term net accumulation of atmospheric carbon dioxide are key ecosystems in these interactions. LÄS MER
4. The role of sediments in the biogeochemical cycles of nutrients in the Gulf of Riga
Sammanfattning : The sediment biogeochemistry of C, N, P and biologic silica (BSi) plays an important role in cycling of these elements in aquatic ecosystems. In shallow coastal and estuarine systems, water-sediment nutrient dynamics can influence biological processes (e.g., primary production) in overlying waters. LÄS MER
5. Visualization, integration and analysis of multi-element geochemical data
Sammanfattning : generated large databases containing information on the concentrations of chemical elements in rocks, surface sediments and biogeochemical materials. Regional geochemical data being imprecise, multivariate, spatially auto-correlated and non-normally distributed pose specific problems to the choice of data analysis methods. LÄS MER