Sökning: "peat accumulation rates"

Visar resultat 1 - 5 av 10 avhandlingar innehållade orden peat accumulation rates.

1. 1. Incorporation and preservation of geochemical fingerprints in peat archives

   Författare :Sophia V. Hansson; Richard Bindler; Dominik Weiss; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Peat; Beryllium; bulk density; C N-ratio; decomposition; deposition; downwash; elemental mobility; geochemistry; humification; lead; light transmission; mercury; peat accumulation; precipitation; Environmental Science; miljövetenskap;

   Sammanfattning : The present status of the environment, including environmental problems such as heavy metal accumulation in aquatic and terrestrial ecosystems, is in part the consequence of long-term changes. Cores from peatlands and other natural archives provide us with the potential to study aspects of the atmospheric cycling of elements, such as metal pollutants, on timescales much longer than the decade or two available to us with atmospheric deposition monitoring programs. LÄS MER

3. 2. Holocene dynamics in subarctic peat plateaus of west-central Canada : Vegetation succession, peat accumulation and permafrost history

   Författare :A. Britta K. Sannel; Peter Kuhry; Peter Jansson; Ian Brown; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; peatlands; permafrost; carbon accumulation; fire; subarctic; Holocene; Physical geography; Naturgeografi;

   Sammanfattning : Dynamics in vegetation, permafrost and peat and net carbon accumulation rates throughout the Holocene have been studied in two subarctic peat plateaus of west-central Canada through plant macrofossil analysis, geochemical analyses and AMS radiocarbon dating. Peatland formation at the studied sites began around 6600-5900 cal yr BP as a result of paludification of upland forests. LÄS MER

4. 3. Mid-Holocene mineral dust deposition in raised bogs in southern Sweden : Processes and links

   Författare :Jenny Sjöström; Malin Kylander; Carl-Magnus Mörth; Bindler Richard; Lisa Belyea; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Paleodust; peat; geochemistry; mineralogy; REE; Holocene; peat accumulation rates; paleostorms; Marine Geology; maringeologi;

   Sammanfattning : Atmospheric mineral dust is a key component of the climate system, which affects insolation, brings nutrients to marine and terrestrial ecosystems, and acts as a cloud condensation nuclei. To reconstruct past patterns in terrestrial dust deposition natural archives may be utilized, such as loess, dunes, lakes, and peat bogs. LÄS MER

5. 4. Holocene carbon and nitrogen accumulation rates and contemporary carbon export in discharge : a study from a boreal fen catchment

   Författare :Anna Larsson; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : The contemporary role of mires in land-atmosphere exchange of carbon dioxide (CO₂) is the subject of intense scientific debate. Investigating patterns and mechanisms of variations in past carbon (C) accumulation rates as well as contemporary C fluxes of peatlands facilitates predictions of future mire C sink strength under a changing climate. LÄS MER

7. 5. Peatland dynamics in response to past and potential future climate change : A regional modelling approach

   Författare :Nitin Chaudhary; BECC: Biodiversity and Ecosystem services in a Changing Climate; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; PEATLANDS; PERMAFROST; Carbon accumulation; Microtopography; LPJ-GUESS; Earth system models;

   Sammanfattning : The majority of the northern peatlands developed during the Holocene as a result of a positive mass balance between net primary productivity (NPP) and heterotrophic decomposition rates. Over that time they have sequestered a huge amount of carbon in terrestrial ecosystems. LÄS MER