Holocene pollen stratigraphy indicating climatic and tree-line changes derived from a peat section at Ortino, in the Pechora lowland, northern Russia

This study presents the results of pollen analysis and radiocarbon dates of a peat section from Ortino, in the Pechora lowland in northern Russia. A p ollen stratigraphy is provided for at least the last 9200 years and it prov ides a basis for the reconstruction of the vegetational and mire history in the northernmost part of European Russia. Conifer stomata content was reco rded as a complement to pollen studies to achieve a better resolution of tr ee-line fluctuations. The onset of Holocene warming initiated a vegetation succession that started first with herb-dominated tundra vegetation, and la ter with herb-shrub tundra. Combined pollen and stomata evidence suggests t hat Picea accompanied by Betula spp. spread to Ortino soon after 9000 14 C yr BP. Trees and a climate warmer than at present persisted until c. 3000 1 4 C yr BP, when forests disappeared and modern dwarf-shrub tundra vegetatio n developed.