Sökning: "Sphagnum fuscum"

Hittade 5 avhandlingar innehållade orden Sphagnum fuscum.

  1. 1. Holocene climate and environmental change in high latitudes as recorded by stable isotopes in peat deposits

    Författare :Päivi Kaislahti Tillman; Steffen Holzkämper; Stefan Wastegård; Peter Kuhry; Thomas W. D. Edwards; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; stable isotopes; Holocene; subarctic; climate; Sphagnum fuscum; kvartärgeologi; Quarternary Geology;

    Sammanfattning : In this thesis, stable carbon and oxygen isotopes in α-cellulose isolated from Sphagnum fuscum moss remains were used as climate proxies. The main focus was to implement the methods in records from high latitude peatlands in the Northern Hemisphere (west-central Canada and north-eastern European Russia), reconstruct palaeoclimate of the studied regions during the Holocene, and evaluate the compatibility of results with other proxy records, especially tree-ring isotope time-series. 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. Effects of enhanced ultraviolet-B radiation on subarctic ecosystems

    Författare :Carola Gehrke; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; pigmentation; photosynthesis; dark respiration; shoot morphology; shoot growth; phanerogams ; species composition cryptogams; productivity; decomposition; dwarf shrubs; bryophytes; peatland ecosystem; heath ecosystem; UV-B; ozone depletion; Plant ecology; Växtekologi;

    Sammanfattning : Biologically harmful ultraviolet-B radiation (UV-B, 280-320 nm) is increasing at the Earth´s surface owing to stratospheric ozone depletion. This is of global concern due to potential impacts of enhanced UV-B radiation on the biosphere. LÄS MER

  5. 4. Myrar på Storön vid Norrbottenskusten

    Författare :Jan Elveland; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Våtmarker; Sverige; Norrbotten; Växtsamhällen;

    Sammanfattning : ELVELAND, J. 1976. Coastal mires on the Storön peninsula, Norrbotten, N Sweden. Wahlenbergia 3. LÄS MER

  7. 5. Holocene climate change in high latitudes recorded by stable isotopes in peat

    Författare :Päivi Kaislahti Tillman; Steffen Holzkämper; Stefan Wastegård; Peter Kuhry; Mats Rundgren; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; -; Quaternary geology; Kvartärgeologi; kvartärgeologi; Quarternary Geology;

    Sammanfattning : A key to the understanding of natural and human induced climate variations is to reconstruct past changes from different environments. No outstanding method for general use has been pinpointed, instead, a need of multi-proxy studies is often stressed and the reconstructions are under constant improvement by new techniques. LÄS MER