Role of Ecosystem Development and Climate Change in Bog Formation in Central Sweden

Abstract

Bog development, in terms of the rates of horizontal and vertical accumulation of peat and the timing of landform development of open-water pools, was examined on two concentric raised bogs in central Sweden. The results are compared with three models (allogenic, autogenic, and neutral models) of bog development in order to evaluate the relative contribution of environmental factors vs. ecosystem control of developmental processes. Both mires began to grow on discrete upland sites -6000 BP and then spread concentrically and accumulated peat vertically at approximately continuous rates to the present. Radiocarbon dates from pool sediments are progressively younger from the center to the margin of the mire, suggesting that pool formation is triggered autogenically by changes in hydrology. The results conform to hydrological models of mire formation based on groundwater mound equations and suggest that autogenic processes exert a major control over bog expansion, landform development, and the formation of conspicuous features in the stratigraphic record.