Advanced search

Showing result 1 - 5 of 8 swedish dissertations matching the above criteria.

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

   Author : Sophia V. Hansson; Richard Bindler; Dominik Weiss; Umeå universitet; []
   Keywords : 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;

   Abstract : 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. READ MORE

4. 2. Quantity and quality of soil organic matter in permafrost terrain

   Author : Gustaf Hugelius; Peter Kuhry; Philip Wookey; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; carbon; soil organic matter; soil organic carbon; permafrost; arctic; upscaling; peat plateau; cryoturbation; active layer; thermokarst; carbon nitrogen ratio; stable isotopes; humification; Physical geography; Naturgeografi; geografi med naturgeografisk inriktning; Physical Geography;

   Abstract : 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. READ MORE

5. 3. The colour of climate : A study of raised bogs in south-central Sweden

   Author : Anders Borgmark; Stefan Wastegård; Ann-Marie Robertsson; Bas van Geel; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Holocene; south-central Sweden; peat humification; bog hydrology; climate variation; spectral analysis; Quaternary geology; Kvartärgeologi;

   Abstract : 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. READ MORE

6. 4. Tree-limit ecotonal response to Holocene climate change in the Scandes Mountains of west-central Sweden

   Author : Jonas Bergman; Kvartärgeologi; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; tree-limit ecotone; alpine vegetation; tephrochronology; peat humification; plant macrofossils; Palaeobotany; fylogeni; Paleobotanik; palynology; phylogeny; palynologi; Geologi; Geology; pedology; geomorphology; Physical geography; klimatologi; geomorfologi; climatology; Fysisk geografi; cartography; Holocene climate; palaeoecology; marklära; kartografi; pollen influx;

   Abstract : 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. READ MORE

7. 5. Late Holocene humidity variability in central Sweden

   Author : Sofia Andersson; Stefan Wastegård; Gunhild Rosqvist; Kristian Schoning; Frank Chambers; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; humidity change; stable isotopes; Chara spp; Pisidium spp; testate amoebae assemblages; humification; C N ratio; late Holocene; central Sweden; Quaternary geology; Kvartärgeologi; kvartärgeologi; Quarternary Geology;

   Abstract : 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. READ MORE