| 1. |
|
|
| 2. |
- Ukkonen, Pirkko, et al.
(författare)
-
An Arctic seal in temperate waters : History of the ringed seal (Pusa hispida) in the Baltic Sea and its adaptation to the changing environment
- 2014
-
Ingår i: The Holocene. - : SAGE Publications. - 0959-6836 .- 1477-0911. ; 24:12, s. 1694-1706
-
Tidskriftsartikel (refereegranskat)abstract
- The ringed seal (Pusa hispida) is an early immigrant in the Baltic Basin and has since its arrival experienced substantial changes in the climate, salinity and productivity of the Basin. In this paper, we discuss the dispersal and distribution of the ringed seal during different stages of the Baltic Sea in relation to past and ongoing environmental changes. Subfossil ringed seal remains around the Baltic Sea and the Danish Straits were radiocarbon dated in order to map the distribution of the species in different time periods. The delta C-13 data were used in evaluating the changes in the marine character of the Baltic Basin. The sequence of the dates indicates a continuous presence of the species in the Baltic Basin. The earliest ringed seal finds come from the Skagerrak/Kattegat area (Denmark, Swedish west coast) and date to the full glacial period and Baltic Ice Lake. In the Baltic Basin, the species appears in the subfossil record during the Ancylus period, but the main part of the remains date to the Littorina stage. During the Littorina stage, the distribution of the species was at least periodically wider than today, covering also southern parts of the Baltic. The presence of breeding populations in southern parts of the Baltic during the Holocene Thermal Maximum (HTM) indicates that the winters were at least periodically cold enough for winter ice. The changes in the marine influence in the Baltic Basin can be seen in the seal collagen delta C-13 values, which serve as a proxy for qualitative changes in water mass salinity.
|
|
| 3. |
- Ukkonen, Pirkko, et al.
(författare)
-
History of the reindeer (Rangifer tarandus) in the eastern Baltic region and its implications for the origin and immigration routes of the recent northern European wild reindeer populations
- 2006
-
Ingår i: Boreas. - : Wiley. - 1502-3885 .- 0300-9483. ; 35:2, s. 222-230
-
Tidskriftsartikel (refereegranskat)abstract
- A total of 45 subfossil reindeer (Rangifer tarandus) antlers and bones - artefacts excluded - have been found over the years in the Baltic countries of Estonia, Latvia and Lithuania. The relatively high number of specimens suggests a stable residence of the species in the eastern Baltic region. For the first time, 12 of these finds were radiocarbon-dated. The ages of the samples range between 12085 and 9970 C-14 yr BP (14180-11280 cal. yr BP), and cover the Lateglacial and early Holocene, a time period during which climatic conditions shifted from periglacial to temperate. The dates suggest a rapid colonization of the area during the deglaciation period and a local extinction around the Pleistocene-Holocene boundary. The results of the study do not support the theory that the recent wild reindeer populations of northern Europe had their origin in the Late Weichselian reindeer populations of the eastern Baltic region.
|
|
| 4. |
|
|
| 5. |
- Ukkonen, Pirkko, et al.
(författare)
-
MIS 3 mammoth remains from Sweden - implications for faunal history, palaeoclimate and claciation chronology
- 2007
-
Ingår i: Quaternary Science Reviews. - : Elsevier BV. - 0277-3791. ; 26, s. 3081-3098
-
Forskningsöversikt (refereegranskat)abstract
- The distribution of low-arctic megafaunal remains in time and space from the area previously covered by the Scandinavian Ice Sheet(SIS) suggests the presence of breeding mammoth populations in the circum-Baltic region during the time interval from 44 to 26 ka ago. The transport history of 30 mammoth teeth and bones from southern and north-central Sweden was estimated and the remains were subjected to osteological analyses and 14C dating. Oxygen isotope analyses of tooth enamel indicate a palaeoclimate considerably more homogenous than that experienced in Sweden today, showing moderate north–south gradients in the d18O value of precipitation and temperature. In general, the results support the model of restricted ice sheet distribution during the second half of the Middle Weichselian. The clear discrepancy in the inferred absence of glaciation in the central Swedish uplands and the Baltic basin as evidenced by the Swedish mammoth data versus the Danish OSL-based glaciation chronology in the period from 40 to 30 ka ago is discussed in the light of radiocarbon calibration and glacial dynamics. r 2007 Published by Elsevier Ltd.
|
|
| 6. |
- Ukkonen, Pirkko, et al.
(författare)
-
Muinainen metsästys.
- 2005
-
Ingår i: Jahtimailla 2. Riistanisäkkäät..
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- The early Stone Age hunters in southern and central Finland were specialized in game species living in young deciduous forests, such as the European elk, the beaver, and the Arctic hare. Later on, the game was enriched by species associated with pine and mixed oak forests, such as the brown bear, the pine marten, the red squirrel, and the forest reindeer. In Lapland the subsistence of the early hunters was based nearly exclusively on wild reindeer, on the coast on seals.
|
|
