Jökull - 01.12.1999, Blaðsíða 11

10,900-10,600 BP
This period is represented by RPAZ Skagi-2 (Fig.
5), which was identified in Lake Torfadalsvatn and
Lake Flraunsvatn (Rundgren et al., 1997). Shrubs and
dwarf shrubs (Betula nana, Salix, Juniperus communis
and Empetrum nigrum) expanded on northernmost
Skagi after 10,900 BP. Although grasses and herbs
were still important (Rundgren, 1995; Rundgren et al.,
1997), the vegetation in the period 10,900-10,600 BP
may be described as a dwarf-shrub tundra. Capsella
bursa-pastoris type, Ranunculus type, Thalictrum
alpinum, Apiaceae, Chenopodiaceae, Caryophyl-
laceae and Oxyria + Rumex are the most abundant
herb-pollen types recorded. Plant cover was probably
discontinuous, but increased towards 10,600 BP. This
indicates a gradual warming, and is supported by the
limnic data. July temperatures at least as high as today
are suggested by the relative abundance of Myriophyl-
lum and Isoetes. It was proposed by Rundgren (1995)
that the coasts of Skagi experienced long seasons
without sea ice between 10,900 and 10,600 BP, and
according to Rundgren et al. (1997) this was a period
Fig. 6. Tentative l4C-year-based relative sea-level curve for northernmost Skagi. The altitudes of the studied sites are shown as
horizontal solid lines, and the mapped raised beach ridges (A-C) as horizontal dashed lines. Regional pollen assemblage zones
for northemmost Skagi are shown at the top of the figure. From Rundgren et al. (1997). - Línurit byggt á ‘4C aldri sem sýnir
afstœðar sjávarstöðubreytingar á nyrsta hluta Skaga. Hœð athugunarstaða yfir sjávarmáli er sýnd sem láréttar heilar línur og
ummerki umfornar sjávarstöður (A-C) er sýnd sem láréttar strikalínur. Frjókornasamfélög fyrir nyrsta hluta Skaga eru sýnd
efst á myndinni (Rundgren o.fl. 1997).
JÖKULL, No. 47, 1999
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