The 21st century climate change effects on the forests and primary conifers in central Siberia

Abstract

Regional studies have shown that winters warmed 2-3 °C while summers warmed 1-2 °C during the1960-2010 period in central Siberia. Increased warming predicted from general circulation models (GCMs) by the end of the century is expected to impact Siberian vegetation. Our goal is to evaluate the consequences of climate warming on vegetation, forests, and forest-forming tree species in central Siberia. We use our envelope-type bioclimatic models of the Siberian forests and major tree conifer species based on three climatic indices which characterise their warmth and moisture requirements and cold resistance, and on one soil factor that charactrises their tolerance to permafrost. Coupling our bioclimatic models with the climatic indices and the permafrost distributions, we predict the potential habitats of forests and forest-forming tree species in current climate conditions and also in the 2080 projected climate. In the 2080 drier climate conditions, Siberian forests are simulated to decrease significantly and shift northwards while forest-steppe and steppe would come to dominate 50 % of central Siberia. Permafrost is not predicted to thaw deep enough to sustain dark (Pinus sibirica, Abies sibirica, and Picea obovata) taiga. Dahurian larch (L. gmelinii+cajanderi), which is able to withstand permafrost, would remain the dominant tree species. Light conifers (Larix spp. and Pinus sylvestris) may gain an advantage over dark conifers in a predicted dry climate due to their resistance to water stress and wildfire. Habitats for new temperate broadleaf forests, non-existent in Siberia at present, are predicted by 2080.