Consequently,the history materials mentioned the problems in the Wan Li period,such as the sand stuffed up the side wall of the Yansui Middle Road and the fierce quicksand of the southeast area of the Maowusu Desert factors.

• 史籍描绘的万历年间延绥中路边墙沙壅问题及毛乌素沙地东南缘流沙猖獗,是自然因素所致。