Radiocarbon dated Pinus sylvestris L-wood from beyond tree-line on the Kola Peninsula, Russia

Radiocarbon dates were obtained from 24 samples of Pinus sylvestris L. (Sco ts pine) wood recovered from sites beyond the modern conifer tree-line on t he Kola Peninsula of Russia. Twenty-one of the samples came from the shallo w waters and eroding peats at the edges of two small lakes at 68 degrees 43 'N, 35 degrees 10'E, located north of the modem conifer tree-line. Three sa mples came from a small pond located above the modem elevational limits of Pinus sylvestris at 68 degrees 25'N, 35 degrees 19'E. The radiocarbon dates indicate that pine trees grew approximately 20 km north of the mapped mode rn limits of the species from 6680 BP to 3830 BP. Pine trees were also grow ing some 40 m above their modern elevational limits between 5890 BP and 345 0 BP. Nineteen of the samples date from 6680 BP to 5070 BP, suggesting that the density of trees north of the modern treeline was greatest between sim ilar to 7000 and 5000 BP. The timing of tree-line advance and greatest dens ity on the Kola Peninsula are in agreement with the results of similar stud ies from northern Fennoscandia which indicate that maximum northern and ele vational extension of tree-line occurred between 7000 BP and 4000 BP. The g eneral agreement between tree-line reconstructions suggests that the climat ic changes that promoted mid-Holocene tree-line extension along the North A tlantic margins in northern Fennoscandia propagated eastward to the Kola Pe ninsula. The late timing of initial pine expansion on the Kola and in adjac ent northern Fennoscandia remains problematic and may relate to lower winte r insolation, temperature regimes in the adjacent oceans or slow rates of m igration.