Abstract
Summary
1
A sediment core recovered from Poteryanny Zub Lake on the Kola Peninsula of Russia (68°48′91″ N, 35°19′32″ E) provides fossil pollen and stomate evidence for Pinus sylvestris treeline development and movement. The site today lies in birch forest tundra, approximately 25 km north of the pine treeline and 90 km south of the Murman Coast.
2
The record begins approximately 10 050 14C years before present (bp). The post‐glacial tundra, typified by various herbaceous taxa and Artemisia, was followed by Betula‐dominated woodland forest with Polypodiaceae‐Gramineae pollen types. Such vegetation assemblages are not analogous to any in the western Kola Peninsula today.
3
Stomate evidence demonstrates that Pinus sylvestris immigrated to the study site as early as 8150 14C bp. Pine forest probably expanded northwards from sparse or small disjunct populations, which established c. 1000 14C bp before the expansion evident in the pollen and wood macrofossil records (7200 14C bp). Betula and other shrub and herb taxa declined at this time, possibly as a result of shading by the pine canopy.
4
The presence of fossil Pinus sylvestris stomates and wood, together with AP : NAP ratios, indicates that the pine treeline was some 100 km north of its present position by the end of the middle Holocene warming (7000–6000 14C bp). This places it near the Barents Sea coast, currently tundra vegetation. An approximate 2 °C increase in regional summer temperatures would be necessary to move the treeline to the present‐day coastline.
5
From 6000 14C bp the pine treeline gradually retreated southward to its present modern position. Birch woodland has grown at the site since c. 3000 14C bp.