Sökning: "external climate"

Visar resultat 6 - 10 av 118 avhandlingar innehållade orden external climate.

  1. 6. Factors regulating the origin and magnitude of carbon dioxide emissions from high-latitude lakes

    Författare :Hendricus Verheijen; Jan Karlsson; Cristian Gudasz; David A. Seekell; Marcus Klaus; Anne Ojala; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; lake; carbon dioxide; organic carbon; inorganic carbon; arctic; emission; environmental science; miljövetenskap; climate change; klimatförändringar; Physical Geography; naturgeografi;

    Sammanfattning : Lake ecosystems receive, transmit and process terrestrial carbon and thereby link terrestrial, aquatic and global carbon cycles. Most lakes evade CO2 to the atmosphere, but the annual magnitude of CO2 evasion, as well as sources and mechanisms underpinning CO2 evasion from lakes are still largely unresolved. LÄS MER

  3. 7. Calcium transport in the Pacific oyster, Crassostrea gigas - in a changing environment

    Författare :Kirsikka Sillanpää; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Climate changes; Ussing chambers; Calcium uptake; Sodium potassium ATPase; Calcium ATPase; Sodium calcium exchanger; Calcium channel; Hemocytes; Mantle epithelium;

    Sammanfattning : Pacific oyster, Crassostrea gigas, is globally one of the most important farmed bivalve species. A prominent features of the C. gigas is the thick CaCO3 shell covering the body of the animal and protecting it from the environment. LÄS MER

  4. 8. External Growth Control of Baltic Sea Cyanobacteria

    Författare :Anna Zakrisson; Ulf Larsson; Jakob Walve; Elena Gorokhova; Sanna Suikkanen; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Baltic Sea; cyanobacteria; nitrogen fixation; heterocysts; Aphanizomenon; Nodularia; water treatment; Himmerfjärden; sewage; climate; Marine Ecology; marin ekologi;

    Sammanfattning : In the Himmerfjärden Bay a large excess of nitrogen over phosphorus in the discharge from a large sewage treatment plant (STP) has suppressed growth of diazotrophic cyanobacteria in its inner parts. Implementation of nitrogen removal in the STP in 1997 drastically reduced nitrogen load and triggered growth of diazotrophs, mainly Aphanizomenon sp. LÄS MER

  5. 9. Pollen-based quantitative reconstruction of land-cover change in Europe from 11,500 years ago until present - A dataset suitable for climate modelling

    Författare :Anna-Kari Trondman; Marie-José Gaillard; Chris Caseldine; Linnéuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; pollen data; REVEALS model; model testing; land vegetation; land-cover; Holocene; Europe;

    Sammanfattning : The major objective of this thesis was to produce descriptions of the land vegetation-cover in Europe for selected time windows of the Holocene (6000, 3000, 500, 200, and 50 calendar years before present (BP=1950)) that can be used in climate modelling. Land vegetation is part of the climate system; its changes influence climate through biogeophysical and biogeochemical processes. LÄS MER

  7. 10. The Nitrogen Cycle in Soil - Climate Impact and Methodological Challenges in Natural Ecosystems

    Författare :Anna-Karin Björsne; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Nitrogen cycle; 15N tracing experiments; gross N transformation rates; climate change; climate treatments; mineralization; nitrification; forest fertilization; nitrous oxide emissions; boreal forest soil; tree species; soil organic matter; C:N ratio;

    Sammanfattning : Nitrogen (N) is a fundamental element for life, and limiting in many terrestrial ecosystems. In non-N-fertilized ecosystems, the N inputs can be low, and the nutrient availability for plants is determined by the internal cycling of N. LÄS MER