Impact of Climate Change on Ruderal Communities in the Conditions of Ukraine

We elucidated the reaction of ruderal vegetation community to environmental changes. It made it possible to assess the level and nature of the synanthropic vegetation dynamics, fluctuation processes, and also to indicate the scenarios of evolution of ruderal communities throughout the environmental changes, in particular, climate changes. In this study, we used the original methods: synphytoindications and estimation of the climate change impact and the species reaction according to their ecological strategy. Dataset included 1200 phytosociological relevés of different synanthropic habitat types (borders of fields, ruderal areas, and railway tracks). As a result of vegetation analysis, we obtained 16 alliances of ruderal vegetation belonging to the six classes and two natural vegetation derivatives of the Sedo-Scleranthetea Br.-Bl. 1955 and Festuco-Brometea Br.-Bl. & Tx. 1943. Evaluation of ecological indicator value changes in relation to 1, 2 and 3 °C increase in average annual temperatures allowed to determine how significant is the threat to the existence of ruderal communities. It is particularly noticeable in the thermal regime, and some changes in edaphic properties of soil, especially acidity (pH). Under the conditions of climate changes and ecological indicator value changes, such communities could be easily restored both in the appropriate conditions of the region and outside it, that is, shifting their range. But thanks to this strategy, the emergence of new species and, as a result of this, the formation of completely new vegetation types is possible.