Radial increment dynamics of Scots pine (<Emphasis Type="Italic">Pinus sylvestris</Emphasis> L.) as an indicator of hydrothermal regime of the Western Transbaikalia forest steppe

The radial increment of Scots pine growing in the forest-steppe zone of Western Transbaikalia at five sites is studied. For each site, additional samples are collected, which allows us to increase reliability and build two regional chronologies. An analysis of chronology correlations with monthly temperatures, precipitation, and Selyaninov hydrothermal coefficient is carried out. The analysis of 10-day moving climatic series makes it possible to clarify the periods of climate impact on the increment: the main limitation of pine increment in the region is observed by moisture supply, including conditions during previous (from late July to late September) and current (May to mid-July) vegetative seasons. Fluctuations of 23–35 years in the dynamics of climatic factors and radial increment of the pine are found.