A revised chronology for aeolian activity in subarctic Fennoscandia duringthe Holocene

Detailed sedimentological studies and parallel sampling for C-14 and infra- red stimulated luminescence age assays were undertaken at six sites lying b eyond and below the tree-line with the objective of establishing the histor ical development of aeolian landforms in Lapland. The main issues were: (a) the timing of dune activity and processes of stabilization: (b) the specif ic processes responsible For the past and contemporary activity. New data i ndicate that many of the primary dunes were active for several millennia af ter deglaciation. Diachronous stabilization at both local and regional scal es appears likely. initial stabilization occurred in local interdune areas and where regional dune fields were colonized by pine (generally before 7 k a). Local large dunes and some regional dunefields only became stable aroun d 4.3 ka, when the regional groundwater table rose and late pine colonizati on was possible. The latest episode of aeolian activity dates from AD 1100- 1650 across the area. A unique deflation triggering Factor was not identifi able, suggesting that several agents acted in combination. Climate-vegetati onal parameters, especially the 'Little Ice Age' event, together with reind eer trampling, appear responsible Tor the continuing aeolian activity at th e tundra sites. At the margin of the pine forest zone, forest fires may be the cause of aeolian reactivation.