Surface wetness and mire development during the late Holocene in central Sweden
(English)In: Boreas, ISSN 0300-9483Article in journal (Refereed) Accepted
Late Holocene mire development and surface wetness changes have been studied in a small mixed mire located in central Sweden. Today the mire is characterised by a mainly ombrotrophic centre dominated by Sphagnum mosses whereas Carex content increase towards the more minerotrophic mire margins. Two peat sequences extracted from the central ombrotrophic part were investigated for stratigraphy, humification, testate amoebae analysis, C/N ratio and 13C and 15N stable isotopes. Three main stages of mire development are identified with a first stage between ca 4200-2600 cal yr BP, characterised by water-logged conditions suggesting a minerotrophic fen stage. The second stage between ca 2600-1000 cal yr BP is characterised by more ombrotrophic conditions and Sphagnum dominated vegetation. The onset of the prominent change at ca 2600 cal yr BP could have been initiated by by climate change coincident with a change in solar activity. The last stage, between ca 1000-50 cal yr BP, is dominated by more ombrotrophic conditions suggesting increased precipitation. This study shows that the response of hydrological proxies in a mixed mire during its development towards more ombrotrophic conditions might result in conflicting results, which has to be considered in palaeoenvironmental reconstructions from mires that changes between ombrotrophic and minerotrophic settings.
mire development, testate amoebae, surface wetness, C/N ratio, humification, late Holocene, central Sweden
Research subject Quarternary Geology
IdentifiersURN: urn:nbn:se:su:diva-36881OAI: oai:DiVA.org:su-36881DiVA: diva2:290875