Analysis of the relationship between climatic factors and genetic diversity of pedunculate oak populations in different parts of the Republic of Bashkortostan

The geomorphological heterogeneity of the Southern Urals, the impact of air masses from the Atlantic Ocean and internal territories of the Arctic and Siberia form a significant intra- and interannual variation of temperature and precipitation in the Republic of Bashkortostan, which is a Russian region with an area of about 143 thousand square kilometres. The aim of the present study is to analyse the spatial and temporal dynamics of these two most important environmental factors in the light of the results obtained in the study of genetic differences in pedunculate oak populations. For genetic analysis, plant material was sampled in 14 natural stands of the region, 412 loci of single nucleotide polymorphisms of nuclear DNA were used. Information on the dynamics in 2004-2019 of temperatures and precipitation in the southern, central, northern and western parts of the Republic of Bashkortostan is also used in the context of months. We have shown that temperatures in all meteorological stations vary by months and years quite synchronously. The studied territories differed much more in the mode and amount of precipitation, the differences reached a statistically significant level of 59.7% (mainly in the months of the growing seasons) of monthly comparisons of pairs of the stations. At the same time, the populations of pedunculate oak have similar levels of genetic diversity and are genetically relatively weakly differentiated, which proves the system's stability to environmental factors under global climate change. It is discussed that the phenomenon revealed may be related to the effectiveness of a genetically realized pollen flow, including between remote stands.