Sökning: "peat humification"
Visar resultat 1 - 5 av 8 avhandlingar innehållade orden peat humification.
1. Incorporation and preservation of geochemical fingerprints in peat archives
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
2. Quantity and quality of soil organic matter in permafrost terrain
Sammanfattning : High latitude terrestrial ecosystems are considered key components in the global carbon (C) cycle and hold large reservoirs of soil organic carbon (SOC). Much of this is stored as soil organic matter (SOM) in permafrost soils and peat deposits and is vulnerable to remobilization under future global warming. LÄS MER
3. The colour of climate : A study of raised bogs in south-central Sweden
Sammanfattning : This thesis focuses on responses in raised bogs to changes in the effective humidity during the Holocene. Raised bogs are terrestrial deposits that can provide contiguous records of past climate changes. Information on and knowledge about past changes in climate is crucial for our understanding of natural climate variability. LÄS MER
4. Tree-limit ecotonal response to Holocene climate change in the Scandes Mountains of west-central Sweden
Sammanfattning : The aim of this thesis was to reconstruct the Holocene vegetational and climatic development in the Sylarna-Storulvån area, western Jämtland, in the central Scandes Mountains. Temporal trends and fluctuations in the elevation and vegetational character of the tree-limit ecotone were studied mainly by means of pollen and plant macrofossil analysis of two lake sediment sequences (Lakes Stentjärn and Spåime), located above the present-day tree-limit. LÄS MER
5. Late Holocene humidity variability in central Sweden
Sammanfattning : The aim of this thesis was to reconstruct humidity variability in central Sweden during the late Holocene. A multi-proxy approach was used to infer humidity changes as recorded in a lake and a mire. Age-models were constructed based on radiocarbon dating and the Askja-1875 tephra. LÄS MER