A group of ecologists found that one of the causes of fires in the forests of Siberia is global warming. As a result of the warming, fir and cedars are deprived of significant water reserves.
According to Vyacheslav Kharuk of the Forest Institute of the Russian Academy of Sciences in Krasnoyarsk, fir and cedar are moisture-loving conifers, so-called "fog trees." Trees weakened by lack of water become more susceptible to the influence of phytopathogens. At the same time, due to an increase in the duration of the growing season and an increase in aridity of the climate, insect pests increase the number of their populations, expand their habitats, and move to the highlands and to the north.
In the past few years, the number of fires in the south of Siberia, in Transbaikalia and in several regions of the European part of Russia has increased significantly. In the last two years alone, hundreds of thousands of hectares of forest were burned on the territory of Khakassia, Buryatia and some other southern regions of Siberia, despite the fact that local residents, together with the authorities, tried to prevent and extinguish fires. The economic damage from this kind of fires over the past year amounted to 12 billion rubles, and in 2015 - about 60 billion.
According to Haruka, one of the reasons for the current situation is climate change. According to the forecast of the Intergovernmental Panel on Climate Change, average temperatures in this century will rise by about 1.1-6.4 degrees. This can lead, and in some cases has already led to changes in the distribution of precipitation, currents, as well as significant restructuring of ecosystems.
For more than four decades, Russian scientists, together with their colleagues from NASA, have been observing changes in the properties of already dead and living trees under the influence of climatic changes on the slopes of the Alps. To this end, researchers are monitoring not only the processes of growth, drying and decay of plants, but also changes in the communities of pests and other insects associated with these plants. In addition, shifts in soil moisture are being studied.
It was found that global warming had different effects on forest growth in northern and mountainous regions, as well as in the lowlands of southern Siberia. Global warming in the south has had a negative impact due to the fact that trees have lost access to sufficient water. As a result, old trees began to die much faster, and the growth of new trees slowed down significantly.
The situation in the mountains looks somewhat different - on the slopes of the Altai Mountains, fir and cedar forests are currently flourishing. Moreover, the growth rate of trees here, according to scientists, not only did not decrease, but even increased by 50-90 percent. As the researchers note, due to the increase in temperatures, the forests have moved towards the peaks by about 150 meters. The situation has improved in a similar way in the northern regions of Siberia, where larch, cedar and fir began to grow significantly faster than in the 1960s.
Thus, Kharuk notes, there is no point in restoring fir and cedar forests in those territories where the ecological and climatic conditions have changed, as a result of which these territories no longer meet the requirements of these tree species. Replacing fir and cedar in these areas with drought-resistant tree species will be the most optimal solution.
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