Radiocarbon wiggle-dating of elm declines in northwest Denmark and their significance

Four elm declines were found in a pollen diagram from a small lake in northwest Denmark. Matching consecutive radiocarbon dates with the dendro-chronological calibration curve indicated a reservoir effect of 120 years, and dates for the four elm declines were obtained (4530, 4130, 3870, 3410 cal B.C.). The occurrence of apophytes (native plants encouraged by human activities) and increased vegetation diversity during the four elm declines indicates human disturbance. The first and second elm declines coincide with traces of early agriculture in northern Germany. The third and fourth elm declines are contemporary with the transitions to the Early Neolithic and the Middle Neolithic Funnel Beaker Culture in Denmark. The possible influence of outbreaks of elm disease is discussed.