Reaction of seed products of different scots pine ecotypes in geographical forest crops to climate change

The responses of trees and stands of forest-steppe and steppe ecotypes of Scots pine (Pinnus sylvestris L.) to climatic changes in relation to their current conservation and sanitary condition are considered. According to radial wood cores taken in 62-year-old seed offspring of pines of different geographical origin from 96 model trees on 32 test areas, trends in the width of annual rings and their structure by calendar years have been established. Using the exam-ple of a specially protected natural territory (the Stupinskoye Field natural monument in the Voronezh Region), where no active economic measures were carried out that affect the growth and sanitary condition of stands during their life-time, the magnitude and nature of the responses of radial growth of trees of different ecotypes of pine to climate changes with differentiation are shown. trends in ring widths by growth periods. Based on statistical processing of ex-perimental data from measurements of 96 wood cores, three age periods of changes in growth trends in diameter have been identified, namely, an increase in the width of annual rings, their decrease and stabilization. Its physico-mechanical properties (hardness, density, fracture resistance, etc.) depend on the width of the annual wood layers of growing trees over their entire height, as well as on the ratio of the fractions of early and late wood that has broken off. The width of the annual layers of early wood is determined both by the temperature regime of the air and the soil as a whole during the spring and summer growing season, and by the amount of precipitation with varying intensity and frequency. It is proved that the growth trends of model trees in the studied cultures of forest-steppe and steppe eco-types of pine on 32 test areas synchronously reflect climate warming, but with differences due to their intraspecific and genetic diversity.