Dynamics of the Seasonal Rhythm of Development Holly Maple ( L.) in the Bashkir Cis-Urals Due to Long-Term Climate Changes

The seasonal rhythm of development in the South Ural Botanical Garden of Ufa was analyzed for the period 1956–1967 and 2013–2024 for 7 phenological phases. The average long-term dates of the onset of the seasonal development phases, the earliest and latest dates for the observation periods, the sums of positive and effective temperatures, and the sums of precipitation falling on the date of the onset of the development phase were determined. It has been established that the dates of the onset of the initial phenological phases of the Norway maple have a positive relationship, while the autumn phases of development have a negative relationship with climatic parameters, such as the sum of effective temperatures and the sum of precipitation. Most of the phases of seasonal development of Norway maple have shifted to earlier dates in recent years compared to the mid-20th century. Vegetation now begins 9 days earlier, and flowering – 5 days earlier, ripening of fruits according to average dates occurs 4 days later. The average annual temperature in the study region in the 21st century increased from 3 to 4.7 °C, and precipitation in the summer and early autumn periods became significantly less. Climate warming is confirmed by a change in the climatic zone: in the mid-20th century was zone 2 (absolute minimum from −40.0 to −45.6 °C), now – zone 3 (from −34.4 to −40.0 °C). The shift in vegetation periods under climate change conditions indicates high phenological plasticity of .