Vegetation history of Molinia heaths in Tysvær, Rogaland, western Norway

Investigations were undertaken in an area of western Norway, approximately 30 km from the coast. The area is dominated by Molinia caerulea heaths on gentle slopes of silt-dominated glacial deposits. Pollen analyses were made on 3 soil profiles. Each profile could be divided into 2 local pollen assemblage zones (PAZs) corresponding with a change from dry to damp soils. From a comparison of the fossil pollen assemblages with pollen assemblages from surface samples collected from present-day Molinia heaths, and a radiocarbon date, the Molinia heaths can be shown to have originated about 1900 years BP. The persistence of the Molinia heaths is probably related to the high water-holding capacity of the sediments and the influence of human activity.