en English is Íslenska

Article

Agricultural University of Iceland > Rafræn tímarit > Búvísindi = Icelandic agricultural sciences >

Please use this identifier to cite or link to this item: http://hdl.handle.net/1946/19878

Title: 
  • Birch hybridization in Thistilfjördur, North-east Iceland during the Holocene
  • Title is in Icelandic Kynblöndun ilmbjarkar og fjalldrapa í Þistilfirði á Nútíma
Keywords: 
Published: 
  • 2014
Abstract: 
  • Past episodes of birch hybridization in Iceland were studied by pollen analysis. The low stature and polycormic form of downy birch Betula pubescens in the subarctic probably results from such hybridization with the dwarf birch Betula nana. Two previous studies in different regions in Iceland revealed events of hybridization connected to early B. pubescens expansion. The present study examined a peat monolith from Thistilfjördur, North-east Iceland, covering the last ten thousand years. Betula pollen was measured, proportions of B. nana and B. pubescens calculated and the presence of hybrids estimated. Betula pubescens expansion started around 7.2 cal ka BP with a peak in non-triporate pollen, indicating hybrids. Low Betula pollen concentrations followed. A second period of considerable hybridization is indicated around 3.3 cal ka BP. Both peaks were associated with B. pubescens expansion.

  • Abstract is in Icelandic

    Tegundablöndun ilmbjarkar og fjalldrapa var rannsökuð í frjókornum. Lágar og margstofna ilmbjarkir á norðlægum slóðum eru líklega afleiðing slíkrar blöndunar. Tvær eldri rannsóknir frá mismunandi landshlutum sýndu hrinur blöndunar snemma á Nútíma sem tengdust framrás ilmbjarkar. Í þessari rannsókn voru sýni tekin úr mósniði í Þistilfirði, sem spannar síðustu tíu þúsund ár. Birkifrjókorn voru mæld, hlutföll tegundanna reiknuð og leitað ummerkja um blöndunina. Ilmbjörk tók að breiðast út fyrir um 7200 árum og fram kom toppur afbrigðilegra frjókorna sem gefa til kynna fjölda blendingstrjáa. Tímabil með litlu birki fylgdi í kjölfarið en önnur hrina erfðablöndunar varð fyrir um 3300 árum. Báðar hrinurnar tengdust aukinni útbreiðslu ilmbjarkar.

Citation: 
  • Icelandic agricultural sciences 27, 95-109
ISSN: 
  • 1670-567x
Accepted: 
  • Oct 3, 2014
URI: 
  • http://hdl.handle.net/1946/19878


Files in This Item:
Filename Size VisibilityDescriptionFormat 
Karlsdóttir et al 2014.pdf2.96 MBOpenHeildartextiPDFView/Open