TRENDS IN THE SPRING DEVELOPMENT OF VEGETATION IN THE CONTEXT OF THE LANDSCAPE DIVERSITY OF THE URALS IN THE CONTEXT OF CLIMATIC CHANGES

Abstract

Natural Biosphere Reserve, Yaksha The article deals with the results of research trends in the spring development of vegetation in the landscape areas and provinces of the Northern, Middle and South Urals from 1925 to 2019. According to the archives of The Russian Geographical Society, stock materials of nature reserves and meteorological stations, as well as expeditionary studies, the calculation of meteorological indicators, the average perennial dates of the occurrence of phenomena and their trends. When analyzing the array, the method of selecting corrective data is tested when calculating quantitative indicators of spring phenology processes. As the main material for the analysis, data on climatic and fenological phenomena, characterizing the beginning, middle and end of spring: beginning of birch sap flow ( Betula Pubescens; Betula Pendula Roth.), beginning of the blooming leaves birch and the beginning of the blossom of the cherry ( Padus Avium Mill.). The paper presents latitudinal, long-term and high-rise gradients and the speed of promotion of phenomena in space, the boundaries of spring are installed in all landscaped provinces. A special emphasis in the article is made on the trends in the thermal regime and spring development of birch and cherry for the provinces. The relationship is established between the timing of the onset of spring phenomena, thresholds of temperatures +5 °C, +10 °C, +12 °C and +14 °C, as well as the effect of the sums of positive temperatures on the phenoindicator phenomena. Negative trends have been established changes in the average annual air temperature and spring processes in birch and cherry, indicating the displacement of the timing of seasonal phenomena earlier and characterizing the dynamics of the spatial-temporal structure of natural complexes of the Urals. Unidirectional, but various variables of trends are determined by a