Based on the principle of forest engineering systems of the torrent control,the importance,current stute,background,principle and method of planning in the risk area of the Alal were described.

In recent years,with the development of information technology and the application of landscape ecology and ecology economics in torrent control ,in the field of torrent control,some progress was made in theory and research method.

Application of image segmentation in desertification control effect evaluating;

Based on the analysis of the present situation in soil and water erosion ws well as desertification in Qinhai, some problems with soil and water conservation as well as desertification control were pointed out and suggestions relevant were put forward.

The major polymer materials used in desertification control are introduced, and feasibilities and problems regarding their application in stabilizing sandy soils and absorbing and holding water are discussed.

On the Function of China's Government in Combating Desertification;