Karl Ljung

Plant macrofossil and pollen records from the partially varved sediments of Lake Odensjön in southernmost Sweden provide detailed information on local forest development and land-use history within Söderåsen National Park during the past 600 years. A relatively dense forest dominated by Fagus (European beech) covered the steep talus-dominated slopes surrounding the lake during at least a century prior to c. 1550 CE, when a change towards more open conditions occurred in response to intensified grazing. The Fagus population on the slopes was at its minimum at c. 1700–1900 CE, when high Juniperus pollen frequencies indicate the presence of grazed heathlands on the horst plateau above. Reduced grazing pressure caused renewed and rapid forest expansion after c. 1900 CE, which resulted in development of the Fagus-dominated forest with a homogenous age structure that characterises the slopes near the lake and large parts of the park today. This dynamic forest history is supported by dendrochronological data from the local Fagus population and information from historical maps, documents and aerial photographs. It is also consistent with palaeoecological evidence from Fagus-dominated forests in other agriculturally marginal areas in southernmost Sweden, suggesting that these were shaped by a similar land-use history. Therefore, the recent and rapid forest development revealed in this study has implications for management strategies aiming at conservation of Fagus-dominated forest in similar settings in this part of Sweden and neighbouring countries.