Climate response in radial growth of Larix cajanderi and Pinus sylvestris in Central Yakutia

Climate change, characterized by increased temperature fluctuations and alterations in precipitation and soil moisture conditions, can significantly impact ecosystems that experience both moisture deficits and excesses. Even small changes in precipitation and air temperature can significantly affect tree growth. This paper examines the statistical parameters of the width of annual rings and the results of dendroclimatic analysis of larch ( Larix cajanderi Mayr .) and pine ( Pinus sylvestri s L.) growing in the zone of continuous permafrost. The forest areas where larch and pine samples were collected are located near the village of Magan and the urban-type settlement of Nizhny Bestyakh in the central part of the Republic of Sakha (Yakutia). Woody plants are characterized by a longlife cycle, the annual rings of which are able to store information about their growth. This important resource allows obtaining valuable information about the climate and environmental changes in a given area. To understand how trees respond to climate change, Pearson correlation coefficients were calculated between the width of tree rings and average monthly air temperature, annual precipitation, and the SPEI aridity index using data from the Yakutsk weather station. To identify the response of different tree species to climate change over the past 30 years, each year was considered as a separate period. We assume that air temperature, which tends to increase, is one of the limiting factors that affects precipitation and dry periods. Due to the lack of moisture in the form of rain, tree species experience difficulties. They mainly receive moisture from the active layer of permafrost, which accumulates autumn precipitation of the previous year. Overall, we observe a negative response to the increase in air temperature in the surface layer of the atmosphere. On one hand, this suggests a decline in the radial growth of larch and pine; on the other hand, tree species are adapting to the changing climatic conditions in the central region of Yakutia.