This paper aims to monitor desertification evolution of different stages and assess its factors using remote sensing (RS)
data and cellular automata (CA)-geographical information system (GIS) with an adaptive analytic hierarchy process (AHP) to derive weights of desertification factors. The study areas (114°E to 117°E and 39.5°to 42.2°N) are one of the important agro-pastoral transitional zone, located in Beijing and its neighboring areas, marginal desertified areas in North China. Desertification information including NDVI and desertification area were derived from the satellite images of 1987TM, 1996TM (with a resolution of 28.5), and 2006 CBERS-(with a resolution of 19.5 m) in study areas. The ancillary data in terms of meteorology, geology, 30m-DEM, hydrography can be statistical analyzed with GIS technology. A CA model based on the desertification factors with AHP-derived weights was built by AML program in ArcGIS workstation to assess the evolution of desertification in different stages (from 1987 to 1996, and from 1996 to 2006). The research results show that desertified areas was increased by 3.28% per year from 1987 to 1996, so was
0.51% per year from 1996 to 2006. Although the weights of desertification factors have some changes in different stages,
the main factors including climate, NDVI, and terrain did not change except the values in study areas.
According to the analysis of remotely sensed data and other multi-information of study area (its longitude: 113.5°-117° and latitude 39.5°-42°), the authors dynamically evolved desertification of Beijing and its neighboring areas, which the images were used in three different periods, 1987 TM, 1996 TM and the CB-1s CCD 4, 3, 2 bands of 2000, 4 orbits and 16 (CBERS-1) scenes (the resolution is 19.5m). By synthetically analysis, we obtained the area desertification distribute and evaluated space-time information. Based on the remote sensing interpretation and database of desertification multi-information efficiency distilled from geology, hydrography, anthropogeography, agrotype, vegetation and so on, we build up desertification dynamic simulation model with CA (Cellular Automata) theory and GIS (Geographic Information System) tool. Then utilizes this model to predict desertification development of Beijing and its neighboring areas. The result of the experiment proves that the model is effective to simulate desertification development in terms of macroscopic and microcosmic. The desertification of Beijing and its neighboring areas develop from west to the east, the southern edge is 72km to Beijing city where lies in the north of Jundu mountain crossing Yanshan with Taihang mountains, which prevents the development of desertification.