Фенологические тренды в природе центральной части Русской равнины в условиях современного потепления
The study addresses changes in the phenological characteristics of common birch (silver birch), bird cherry, mountain ash (rowan), and small-leaves lime (linden) in the central part of European Russia (ER) on the basis of multiyear observations of the beginning of the first leaves unfolding phase for birches and the flowering phase for bird cherry, mountain ash, and linden in the period since 1976 and until 2015 (the period of most intense modern warming in Russia). Overall, the current climate change affects the phenology of all these species; however, various species demonstrate spatial and calendar differences in their phenological reactions. Bird cherry and rowan do not demonstrate significant trends in their flowering dates (or weak positive values of the linear trend coefficient) in territories located between 52° and 54° N. To the north and south of that area, the value of the coefficient is negative: up to –1.5 days/10 years for cherry, and up to and 1.0 days/10 years for rowan. However, for linden, the area of positive values extends northwards to 56° N. The discrepancies in the trends of phenological stages and trends of dates of the stable transition of the air temperature across threshold values close to the phenological stages are 2 – 10 for birch, bird cherry and rowan and up to 8–25 times for linden. A similar correlation has been observed between the phenological trends and sums of active temperatures. This demonstrates the work of adaptation homeostatic mechanisms in the plants in response to the climate change.