?
Подверженность природных систем суши опасным гидрометеорологическим явлениям и пороговые значения их воздействий
Dangerous hydrometeorological phenomena on the territory of Russia that have a significant destructive impact on natural terrestrial systems or their components. 21 categories have been identified: strong wind, tornado, heavy rain, heavy snow, large hail, severe blizzard, severe dust (sand) storm, severe ice and frost deposits (including the formation of ice crust), extreme frost, abnormally cold weather, extreme heat, abnormally hot weather, extreme fire danger, snow avalanches, dry winds, atmospheric drought, high snow cover, floods (of various origins), mudflows, landslides, snow avalanches, abrasion of sea coasts. For each hazardous phenomenon, two levels of threshold values are defined: starting from which it becomes dangerous for natural systems (first threshold) and starting from which the consequences become catastrophic (second threshold). The distribution of phenomena in biomes is given if there is information about impacts at least once in the history of observations. In none of the biomes all events reached the first threshold. Their maximum diversity (20) was noted in the mountain biomes of the Far East. A greater variety of hazardous phenomena of the first threshold level is typical for the southern lowland biomes from broad-leaved forest to steppe and desert, as well as for the southern mountains. Minimal diversity of hazards (13) is observed in some Arctic lowland biomes, as well as Wrangel Island. Altai-Sayan, Baikal-Momsky and South Transbaikal mountain biomes are most susceptible to hazardous phenomena of a catastrophic level. The results of Spearman's rank correlation comparing the distribution of hazardous phenomena across biomes showed the absence in most cases of a significant correlation at the 0.01 level (two-sided significance). Comparing the exposure of biomes to hazardous phenomena of varying intensity, patterns of natural zoning, as well as the similarity of nearby territories, can be traced. The following groups with significant, high and very high connections are distinguished: arctic deserts and mountain tundra; tundra and forest-tundra; forest-tundra and northern taiga; middle taiga; southern taiga, subtaiga and coniferous-deciduous forests; broad-leaved forest and forest-steppe; steppe; deserts. The close connection of mountain biomes with each other in terms of exposure to hazardous phenomena of the first and second threshold levels is higher than with plain biomes.