Changes in the Phenology of Perennial Plants in Western Siberia against the Background of Global Warming

Data on the seasonal development of 78 species of perennial plants in the forest-steppe conditions of Western Siberia have been generalized over a 20-year period (1996–2015) due to changes in the regional climate. It is demonstrated that the meteorological parameters of the warm season of the year in Novosibirsk have undergone significant changes: the average daily air temperature has increased by 0.16°C, the growing season has lengthened by 12 days, and the active vegetation period of plants at temperatures above 10°C has lengthened by 8 days. The correlations of the time of regrowth phenophases and the beginning of flowering of perennials with the data of snow-cover disappearance, dates of transition of average daily air temperatures through 5 and 10°С upward, and sums of these temperatures are detected. Using linear phenological trends, a delay within 2–6 days of the beginning of the vegetation and the advanced beginning of flowering (except for early summer species) by 2–10 days are established. Shortening the duration of prefloral period from 5 to 24 days indicates an acceleration in the rate of the development of perennials against the background of the detected meteorological trends. A change in the duration of vegetation is significant in spring–autumn green and spring–summer–winter green species (10 and 12 days, respectively). Low values of determination coefficient for most trends R2 < 0.06 demonstrated that changes in the phenology of species are mainly caused by interannual variability.