摘要 : Maps of forest types in southern Sweden covering the last 2000 yr reveal a rapid and widespread transformation from rich, mixed deciduous forest types to species-poor coniferous-dominated forest types. The maps are presented at 50... 展开 Maps of forest types in southern Sweden covering the last 2000 yr reveal a rapid and widespread transformation from rich, mixed deciduous forest types to species-poor coniferous-dominated forest types. The maps are presented at 500-yr intervals andare based on syntheses of fossil pollen data. Fagus sylvatica replaced deciduous mixtures in southerly regions, and during the last 500 yr Picea abies became a widespread dominant. This transformation is interpreted as being partially a consequence of the climate-driven, continental-scale migrations of Fagus and Picea, but the major controlling factor appears to have been former land use. This conclusion has significant consequences for 'nature-based' silviculture and conservation of biodiversity. Manythreatened species are associated with deciduous forest mixtures, and these forest types have experienced recent, rapid decline. It is suggested that a biologically sustainable silviculture in southern Sweden should be based on a larger range of tree species than at present, thus mimicking natural conditions and providing a greater diversity of product and biological value for the future. 收起