An understanding of potential natural forest conditions is important for effective management of biodiversity and carbon stocks. Several authors have claimed that primary forest is still widespread in Europe, with primary forest defined as containing “no clearly visible indications of human activities and the ecological processes are not significantly disturbed”. We used palaeoecological methods to test these claims at selected potential primary forest sites in the European north temperate forest zone. We focus on the reconstruction of long-term tree diversity and major anthropogenic disturbance agencies including fire and clearance for agriculture. Both tree diversity and disturbance regime are key determinants of forest ecosystem services and can be reconstructed using analyses of plant macrofossils, pollen and charcoal fragments from dated sediments in very small basins under the tree canopy. Sites were selected from national parks and nature reserves where primary forest was one motive for protection.
Results/Conclusions
Almost all sites studied lost one or more of formerly dominant tree species following earlier periods of anthropogenic disturbance. Disturbance episodes included slash-and-burn agriculture and grazing of domestic animals which were of variable durations between c.150-4500 years ago. Tree taxa lost or severely reduced in population size varied among the sites, but always included combinations of Tilia cordata, T. platyphyllos, Ulmus, Quercus robur, Q. petraea, Corylus avellana, Taxus baccata, Alnus glutinosa, Acer platanoides, Pinussylvestris and Fraxinus excelsior. While climatic change was a likely contributory factor to species loss at the northern margins of the temperate zone, anthropogenic disturbance was the dominant cause of loss. We conclude that European natural temperate forest had greater tree diversity in the past. Reintroduction of lost tree species at individual sites based on the palaeoecological record is recommended as a justifiable measure in forest restoration programmes.
