Sökning: "carbon dioxide"

Visar resultat 16 - 20 av 717 avhandlingar innehållade orden carbon dioxide.

  1. 16. The role of freshwater phytoplankton in the global carbon cycle

    Författare :Fabian Engel; Gesa A. Weyhenmeyer; Don Pierson; Katrin Attermeyer; John A. Downing; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; phytoplankton; carbon dioxide; lake; river; global limnology; spatial scale; carbon budget;

    Sammanfattning : Water flowing through the landscape transports chemical substances including carbon. Along the way from upland soils to the ocean, carbon is transformed from organic carbon into inorganic carbon and vice versa. One such carbon transformation process is the uptake of carbon dioxide (CO2) from the water phase by phytoplankton. LÄS MER

  2. 17. Land-atmosphere interaction of a subarctic palsa mire

    Författare :Marcin Jackowicz-Korczynski; Institutionen för naturgeografi och ekosystemvetenskap; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; eddy covariance; chamber; methnaol; isoprene; nonmethane hydrocarbons; methane; carbon dioxide; carbon; mire; permafrost; subarctic; palsa; greenhouse gas;

    Sammanfattning : The main objective of this thesis was to quantitatively estimate the gaseous exchange of carbon dioxide (CO2) and methane (CH4) between a subarctic wetland ecosystem and the atmosphere. Additionally some initial estimates of the carbon input to the atmosphere of nonmethane hydrocarbons (NMHCs) were also obtained by combining different techniques in a joint setting. LÄS MER

  3. 18. Gas Exchange over Aquatic Interfaces and its Importance for Greenhouse Gas Emission

    Författare :Jovana Kokic; Sebastian Sobek; Erik Sahlée; Marcus B. Wallin; Anne Ojala; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; gas exchange; lake; stream; lake sediment; headwaters; carbon dioxide; methane; greenhouse gas emission; carbon; turbulence; Biology with specialization in Limnology; Biologi med inriktning mot limnologi;

    Sammanfattning : Aquatic ecosystems play a substantial role in global cycling of carbon (C), despite covering only about 4% of the earth surface. They emit large amounts of greenhouse gases (GHG) to the atmosphere, comparable to the amount of C stored annually in terrestrial ecosystems. In addition, C can be buried in lake sediments. LÄS MER

  4. 19. Peatlands at a Threshold: Greenhouse Gas Dynamics in a Changing Climate

    Författare :Magnus Lund; Institutionen för naturgeografi och ekosystemvetenskap; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; chamber; greenhouse gas; nitrous oxide; methane; carbon dioxide; carbon; bog; Peatland; mire; eddy covariance; nitrogen; phosphorus; fertilization;

    Sammanfattning : To be able to predict the strength of climate change and its consequences for mankind, it is of major importance to understand the contemporary greenhouse gas exchange of the terrestrial biosphere, as well as its response to changes in climate. To achieve such understanding both descriptive studies and manipulation experiments are required. LÄS MER

  5. 20. The Carbon Dioxide System in the Baltic Sea Surface Waters

    Författare :Karin Wesslander; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Baltic Sea; carbon dioxide; pCO2; total alkalinity; pH; air-sea gas exchange; inter-annual; seasonal;

    Sammanfattning : The concentration of carbon dioxide (CO2) in the atmosphere is steadily increasing because of human activities such as fossil fuel burning. To understand how this is affecting the planet, several pieces of knowledge of the CO2 system have to be investigated. LÄS MER