荒漠化是当今全球最严重的环境与社会经济问题之一 ,荒漠化以其发展速度和严重的灾害性而引起国际学术界的广泛关注。开展荒漠化变化的驱动因素及其作用机制研究 ,尤其是在此基础上对荒漠化与其驱动因素之间的关系进行量化及动态模拟模型研究 ,对荒漠化的防治和治理具有十分重要的意义。尝试利用3S技术 ,结合元胞自动机理论架构出一套荒漠化动态模拟模型 ,进而对北京及邻区荒漠化的发展趋势进行预测。实验证明 ,这套系统是对荒漠化演化机制从宏观和微观角度进行模拟的有效方法。

Desertification is one of the most serious environment and social economic problem nowadays in the world. Desertification causes extensive concern of international academia for its development speed and serious calamity. It's very significant to study quantitatively the relationships between desertification driving factors and desertification, and to build up dynamic simulation model to predict the expansion of desertification. This paper states how to build up desertification dynamic simulation model based on the cellular automata theory using 3S technology. The design of model based on grid data and embraced two parts: the layer of desertification distributing, and the layer of combination control factor. There fore, the layer of combination control acting as external environment of model impacts and controls the behaviour of desertification expansion. After analyzing syntheses mechanism of desertification expansion, we established six impact factors of desertification, and established this layer's weight coefficients of drive factors by using optimized Analytic Hierarchy Process (AHP). After making certain neighbor configuration and transformation rule,we utilized this model to predict desertification expansion in Beijing and its neighbouring areas. The result of the simulation proves that the model is effective to simulate desertification expansion in terms of macroscopic and microcosmic. According to the research we can say that the desertification has influence on Beijing and its neighbouring areas for a long time, but the desertification expansion mainly occurs in the northern areas of Beijing.