Interglacial vegetational succession and lake development in Denmark

Abstract

Deposits from three interglacial stages are now known in Denmark. The Eemian Interglacial is the youngest one and is known from marine as well as numerous fresh-water deposits. The Holsteinian Interglacial has been studied only in a marine deposit, whilst a still older interglacial is known from the fresh-water deposits of Harreskov, Olgod and Starup The author has studied the forest succession of the Eemian in the lake deposits at Herning and Hollerup. 7 interglacial pollen zones are recognized. Light requiring plants were frequent in the early and the late stages of the succession, and acidophilous plants increase their frequencies in its later part. The lakes reflect a parallel development from basic to acid conditions, or from calcareous to non-calcareous deposition. The interglacial vegetational succession represented in the deposits at Harreskov and 0lgod is divided into 6 pollen zones. It differs essentially from the Eemian succession. Nevertheless, the general features of the successions are very similar, and the lake development is parallel too. The interglacial vegetational successions thus fall into a protocratic, a mesocratic and an oligocratic stage, the last stage being conditioned by soil evolution rather than by climatic change.