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An attempt is made to reconstruct the palaeoenvironmental Holocene history at the timberline on the basis of the analysis of various palaeoecological proxy indicators available on a marshy area and its surroundings in the Taillefer Massif (Isère. France). The multidisciplinary approach involves analyses of pollen assemblages. plant macrofossils, coleoptera remains. subfossil trunks extracted from lakes or peat-bogs. and charcoals derived from the surrounding soils. This enables definition of the respective roles of five forest taxa ( Pinus uncinata Mill., Pinus cembra L., Larix decidua Mill., Abies alba Mill, and Picea abies L. Karsten) in the evolution of high altitude forests during the Holocene. Pinus uncinata was present on the plateau throughout the Holocene. Larix and Pinus cembra were present only during two periods: 7500-5000 BP and 3500-2000 BP. All trees disappeared from the plateau at about 2000 BP, while, at lower altitude. Abies was replaced by Picea. The action of both climate and early human impact can explain these changes.  相似文献   
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