Vertical Distribution of the Vegetation and Water and Heat Conditions of Qilian Mountain (Northern Slope)

Qilian Mountains extends over one thousand kilometers from east to west and its relative height difference is distinctive, and it is influenced by Tibet plateau and Mogolia-Xinjiang desert, which results in clear climate difference in horizontal and vertical directions. The climatic temperature reduces at the rate of 0.58℃/hm with the increase of altitude, and the amount of precipitation increases at the rate of 18.6mm/hm. The climatic changes make the vegetation distribution with evident vertical gradient rule, the vegetation types from the high altitude are: desert-grassland vegetation, dry shrub-grassland vegetation, mountain forest-grassland vegetation, sub-alpine shrub-grassland vegetation, cold-desert alpine meadow, vegetation, among which mountain forest-grassland vegetation is main vegetation type, and it makes up water resources conservation forest ecosystem with shrub in its upper and lower limits and becomes the main body of Qilian Mountains ecosystem.