天山山系的雪崩危险区分布

ZONING OF HAZARDOUS AVALANCHE AREA IN THE TIANSHAN MOUNTAINS

根据山地生态特征．地形切割深度及河谷横剖面形态和雪崩重视率等，将天山山系雪崩危险区分为：1）低山草原或半荒漠雪崩危险区；2）中山森林-草原雪崩危险区；3）中山草地雪崩危险区；4）高山冰缘带（石质）雪崩危险区；5）高山、极高山冰川带雪崩危险区．

Some natural features controlling the process of avalanche activities and the avalanche hazard-index play an important role in avalanche formation and release, which include the dissected depth, gully and slope pattern and dimensions, avalanche reoccurrencc, etc. in the avalanche area. Avalanche force is also controlled by the profile of valleys. Therefore, the avalanche hazardous areas can be defined as the areas where have the shoilar natural features and avalanche index. According to the characterishcs of vertical zonahon of mountain ecology, dissected depth and profile of vallleys, the hazardous avalanche areas in the Tianshan Mountains can be classified into the following zones: (1) low-mountain steppe of semi-desert hazardous avalanche zone; (2) mid-mountain foreststeppe hazardous avafanche zone; (3) mid-mountdin steppe hazardous avalanche zong; (4) alpine periglacial hazardous avalanche zone; and (5) alping glacial hazardous avalanche zone.