The basic principles of engineering agricultural technique are to prevent soil erosion and save precipitation. The climate conditions in China vary greatly from place to place and it is so even in the same place in different seasons. Besides, China has had a long farming history with a large population and limited land. It is difficult to find spacious flat places for making ACL, so most of the ACL will be made on the hillsides with the slope of 20-25 degree in the mountainous areas, which will be very demanding in terms of engineering agricultural technique.