Geoecology of the Norra Storfjallet Area, Northern Sweden

Abstract

The geoecology of the Norra Storfjillet region is reconstructed from the record of deglaciation beginning about 8000 yr BP with the first break-up of the Fenno-Scandian ice sheet (Stage 1). By Stage 2 valleys below 600 m a.s.1. (the Tirna Valley was an exception) had become free of ice. Stage 3 involved a retreat of small valley glaciers to about 700-800 m, major nunataks appeared on the high plateau, and outlet glaciers were considerably reduced in size. Stage 4 was characterized by a warmer and wetter climate (Mid-Atlantic chronozone, 6000-5000 yr BP) when timberline rose to about 900 m. This led to the development of Spodosols (podzols) under stands of dwarf pine in swale topography. This paleo-podzolic signature was not erased during alpine conditions that typified the Sub-Boreal (Stage 5) and Sub-Atlantic (Stage 6) chronozones that followed. These were periods of lower temperatures and with reduced precipitation initially during Stage 5. Precipitation increased during the Sub-Atlantic and, together with temperature, remained similar to the present. Human settlement began about 6000 yr BP and had a recognizable impact on the landscape. This activity accelerated during the Sub-Boreal and Sub-Atlantic, with more intensive use of the mountains for reindeer procurement. The reconstructions are based upon glacial, geomorphological, pedological, and archaeological evidence.