The impact of fires on the landscapes of the Baikal-Dzhugdzhur type underclimate fluctuations

Abstract

In light coniferous forests of the Baikal-Dzhugdzhur type fires are considered as factors and processes inseparable from the forest landscapes and their dynamics. The study period of 1998–2015 is highlighted as extremely arid. In 2008, 2013–2014, 2018 conducted ground studies of the state of vegetation after fires in the area of Vitim Plateau. The conditions of arid period with high frequency, duration and intensity of fires were the main factors in the dynamics of transformation of the structure of mountain-taiga larch forests. Analysis of cruising materials and expedition research showed that from 1996 to 2015 the area of larch forests with canopy density of 5–7% decreased by 45–50%. The area of burned forests and thin forests increased by 45-48%, and the area of shrubs – by 17.0%. The main part of forests is disturbed at the foot of the mountains and in intermountain depressions, at altitudes of 942 -1100 m. Strong desiccation of the ground cover and consistent ground fires with complete loss of trees and undergrowth activated natural processes of bush formation and prairiefication. The duration and degree of fluctuations in climatic parameters determine the nature of the impact of fires on Baikal-Dzhugdzhur larch forests and the degree of their transformation.