The Periglacial Environment and Distribution of Cryosols in China

Permafrost is defined as a thickness of soil or other superficial deposit, even bedrock, that remains frozen for consecutively two years or more (Muller, 1947). Permafrost, or perennially frozen ground, underlies 2.15x106 km2 or 22.4% of the territory of China (Qui and Cheng, 1995) and can be divided into two broad categories, high-latitude permafrost in northeastern China (0.38x106 km2) and high-altitude permafrost in the Qinghai-Xizang Plateau and some alpine regions in western and eastern China (1.76x106 km2) (Figure 2.11.1). The total area of soils affected by permafrost in China is third in the world, after Russia and Canada, but the area of high-altitude perennially frozen soils is the largest in the world.