Динамика сроков наступления вегетационного периода по природно-почвенным зонам Алтайского края за 1955–2020 годы

Abstract

Global climate changes observed over recent decades have determined the need for more detailed studies of agrometeorological indicator dynamics affecting biological agrophytocenoses productivity; it is important to identify the features of their manifestations in a specific area. Altai region is characterized by a wide range of natural environments due to the combination of lowland and mountainous areas that accumulate and redistribute solar radiation and precipitation on the Earth’s surface to varying extents. One of the key agroclimatic indicators is the length of the growing season, particularly its onset in spring. Research focuses on assessing the dynamics of the onset of the growing season in time (the time span of studies is 1955-2020) and predicting the onset of the growing season for natural zones in the future. To identify a possible shift in the onset dates of the growing season for specific natural zones over a long-term period, we devised two time groups (1955-1990 and 1991-2020) in accordance with the observations from the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. It was revealed that in the zone of chestnut soils of dry steppes, on average for 1955-1990 and 1991-2020, there was a shift in the onset of the growing season to an earlier date, particularly 9 days earlier. The zone of chernozems in the arid and moderately arid steppe, as well as the zone of chernozems of leached and gray forest soils in the middle forest-steppe, podzolized and leached, dark gray and gray forest soils in the foothills of the Salair ridge, demonstrate a shift in the onset of the growing season by 7-8 days earlier. Low dynamics during the onset of the growing season (5 days only) were observed in the zone of chernozems of the foothill plains, foothills, and low mountains of Altai in two subzones: chernozems of the meadow steppe of the foothills and low mountains of Altai and chernozems of typical and leached meadow steppe of the foothills of Altai.