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  • Interglacial deposits at Birch Creek, northeast Interior Alaska
  • Alaska ; Birch Creek ; Diagramme pollinique ; Géographie des régions polaires ; Interglaciaire ; Palynologie ; Paléo-environnement ; Pléistocène ; Quaternaire ; Stratigraphie ; Téphrochronologie
  • On growth problems of mountain birch near its distributional limits in Climatological extremes in the mountains, Physical background, geomorphological and ecological consequences.
  • Growth problems observed in mountain birch under marginal circumstances in northern Sweden and southern Groenland. Extreme summer temperatures and strong winter winds as stress factors are discussed.
  • The Holocene history of a subalpine birch forest enclave: subfossil evidence from central Sweden
  • Birch ; C 14 dating ; Climatic variation ; Forest ; Holocene ; Mountain ; Quaternary ; Snow ; Sweden ; Temperature
  • Spatial patterns and structure of the mountain birch tree-limit in the southern Swedish Scandes - a regional perspective
  • This study improves the understanding of the tree-limit phenomenon in general by identifying and analysing regional spatial patterns of the present-day tree-limit position (m a.s.l.) and structure of mountain birch along relevant topographical
  • Report on the distribution of dwarf birches and present pollen rain, Baffin Island, N.W.T., Canada
  • A distribution map for the dwarf birches is presented for the region from Frobisher Bay northward to Cumberland Peninsula. These shrubs are restricted to favourable habitats which, at the northern limit of the species (6740N) are found on south
  • -facing slopes above the immediate local cooling influence of the sea. Pollen studies within the zone of scattered dwarf birch indicate that pollen dispersal from these low, prostrate shrubs is minimal. Samples of moss collected beneath the bushes have 5
  • Does sewage sludge amendment to soil enhance the development of Silver birch and Scots pine ?
  • with industrial sewage sludge and afforested with birch and pine seedlings. To evaluate the growth of tree seedlings, tree dry biomass, height, diameter, root/shoot ratio, specific root length, shoot and root length were calculated. Higher concentrations of heavy
  • Lake-level reconstructions and paleohydrology of Birch Lake, Central Alaska, based on seismic reflection profiles and core transects
  • Lake-level history during the late Pleistocene and Holocene for Birch Lake, Alaska, was reconstructed using seismic profiles and multiproxy sedimentary analyses including sedimentology, geochemistry, magnetic susceptibility, and palynology
  • Larvae of the geometrid Epirrita autumnata (Bkh.) periodically attack the mountain birch. Birch forests of the Finmarks vidda highland plain in northern Norway, however are seldom defoliated. The hypothesis that the birch forest of the Finmark
  • Birch ; Climatic variation ; Forest ; Holocene ; Human impact ; Human occupation ; Iceland ; Model ; Palaeo-environment ; Palynology ; Simulation ; Vegetation ; Vegetation degradation
  • The AA. have simulated the spatial relationship between temperature change and long-term potential vegetation cover dynamics. The results show that the potential vegetation and birch forest range is highly sensitive to the temperature conditions
  • Biogeography ; Birch ; Chorology ; Holocene ; Palynology ; Phytogeography ; Quaternary ; Turkey
  • Annual variation ; Biogeography ; Birch ; Dendrogeomorphology ; Dendrology ; Impact ; Landslide ; Mass movement ; Slope dynamics ; Wood
  • Goal of this study was to analyze vessel lumen length (LL) and width (LW) change on 49 microsections prepared from 15 landslide-disturbed-birches, because very little is known yet about change of the shape characteristics of vessels of Betula
  • The purpose of this study is to study the processes, both active and inactive, which influence the formation, structure and distribution of subalpine heaths in the Abisko Valley and to compare their ecotope with the adjacent birch forest.
  • The northwestern Alaskan records, when combined with others from eastern Beringia (Alaska and adjacent Canada), suggest important regional variation in vegetation and climate histories during the Duvanny Yar (25,000 - 14000 Yr B.P.) and Birch
  • At the end of the last glacial Poland was covered with an open or rather close pine-birch forest. Four main phases in the history of the environment, human economy and culture are distinguished and described. Human interference into natural
  • Contrasting short-term performance of mountain birch (Betula pubescens ssp. czerepanovii) treeline along a latitudinal continentality-maritimity gradient in the southern Swedish Scandes
  • Birch ; Climate ; Climatic change ; Continental climate ; Forest ; High mountain ; Northern Sweden ; Phenology ; Snow melt ; Sweden ; Temperature gradient ; Tree line