Composition and distribution characteristics of annual plant in desert area in Hexi Corridor

Annual plant is an important and special eremophyte component with rich species diversity in Hexi Corridor. Based on the survey, there are 142 annual plant species belonging to 81 genera and 25 families in Hexi Corridor. Because of the harsh arid desert environment, the annual plant concentrates in a few families, such as Chenopodiaceae, Cruciferae and Gramineae etc. The distribution features obvious geographical, seasonal characters, and the distribution characters varies in different ground substances and different geological features.