Abstract: Some discrepancies in the concept of desertification have lagged theoretical research and controlling practice on desertification in China.The author thinks that the main reason is the lack of common perception of the Dimension of desertification.Land degradation is a broad dynamic process prevalent everywhere,while desertification is an exceptional stage in the process.There should be a discrimination of Dimension between the two definitions.Furthermore,various types of degradation all go through such a process from quantitative change to qualitative change,so we should study and confirm two limits in the desertification stage.One limit is to divide desertification from general land degradation,and the other is to divide desertification from desert.The two limits that consist of a series of criterions mean the Dimension in the conception of desertification.So,in this paper,the author presents the concept of Dimension in desertification,and proposes that some particular prescribe on land degradation in the definition of desertification should be given.Based on explaining to Dimension in the concept of desertification,author has brought forward a suggestion on the definition of desertification.

Key words: desertification, land degradation, concept, Dimension, definition