Reconstructed water tables from two ombrotrophic mires in eastern central Sweden compared with instrumental meteorological data

Abstract

Water-level changes for the last 125 years were reconstructed from two ombrotrophic mires in eastern central Sweden using testate amoebae assemblages. The reconstructed water tables show the same overall pattem with high water tables during the 1950s and 1960s and low water levels from the 1970s until present. The similarity in the two records supports the hypothesis that water-table changes in the ombrotrophic mires of this area are driven by climate change. Correlation of decadal means of reconstructed iV l water levels and instrumental meteorological data was performed to examine the relationship between water table and climatic variability. The results show that the reconstructed water tables are correlated with changes in mean annual temperature (p < 0.05). This contrasts with similar data for other parts of Europe where correlations have been found with summer or annual precipitation and temperature. We A suggest that low rainfall in this area of Sweden makes the peatlands more susceptible to changing temperaHOLOCENE ture and that the lack of a response to precipitation is a function of low rainfall variability over the comRESEARCH parison period. The results show that mire surface wetness responses to climate change are spatially PAPER variable and greater attention should be given to understanding this variability if more accurate palaeoclimatic inferences are to be drawn from longer Holocene records.