Situated in the central-Asia sandstorm region，one of the world’s four largest sandstorm sources，China also suffers from sandstorms from outside the country while being blamed as a sand source to northeast Asia.The other three major sources are in Africa，North America and Australia. The land suffering from desertification has been decreasing by 7,585 sq.km annually in China，and the area of sandy land has also been falling by 1,284 sq.km a year.