CLIMATIC FACTORS INFLUENCING THE VULNERABILITY OF SCOTS PINE TO BARK BEETLES ATTACKS IN THE CENTRAL POLISSYA

Abstract

The aim of the research was to evaluate the changes of climate factors in Central Polissya, which can contribute to Scots pine vulnerability to bark beetle attacks and increase of their population density. In 2005–2018 an average annual and growing season air temperature increased, especially in the southern part of the region. On temperature conditions until 2009, multivoltine bark beetles were possible to develop only one full generation. Thermal conditions in Scots pine stands in the vicinity of 5 meteorological stations in 2010, three meteorological stations in 2012, two meteorological stations in 2015, one meteorological station in 2016, and five meteorological stations in 2018 were favorable for the development two bark beetle generations. Average growing season precipitation for 2005–2018 was inferior to the long-term data for all analyzed meteorological stations, except Olevsk. Average G. T. Selyaninov hydrothermal index value fell to the Forest-steppe “standard” in 2005 and 2009 and to the Steppe “standard” in 2015. Such a decrease is unfavorable for forest trees, which are adapted to the high humidity of air and soil.