Abstract: Issue of LUCC has aroused increasing attentions from international groups and worldwide countries since 1990, and becomes the core program of global environmental change research. Land use and land cover change (LUCC) of oasis in mid-scale is one of the key contents in the environmental change of arid region and has an accumulating effect on environmental change in the arid land. The study on LUCC in the arid region has great significance in regional and global change. Now its research focuses on process, trend, drive forces and environment appraise. In China, the study on the modern process of LUCC is significantly importantfor better understanding land use change and environmental management for sustainable development. This paper analyses the dynamic changes of LUCC in the Sangong River Valley of Fukang County Xinjiang in the past 20 years, and discusses a way of GeoCA model analysis on the spatio-temporal variability of arid LUCC, which can provides LUCC prediction analysis, stimulation and environmental appraise. RS, GIS and GPS is a kind of powerful technique and method in capturing LUCC data and analyzing its spatial change. Establishing mathematical models in the range, speed, regional differences and trend index of LUCC, especially the model of LUCC trend and state, the process and trend of oasis LUCC can be deeply studied, including b-i direction process, single-direction process, positive and negative process, rising and falling trend, etc. these models are applied to oasis of arid region and satisfactory effects have been obtained. Cellular Automaton (CA) Model provides GIS with a bottom-to-top spatio-temporal modeling frame, which is composed of a fourfold：cells, states, neighbors and rules. The simplicity and flexibility make CA able to simulate a variety of behaviors of complex systems. The cellular automaton is built within a grid GIS system to facilitate easy access to GIS databases for constructing the constraints. The essence of the model is that constraint space is used to regulate cellular space. Considering the characteristic of Geo-Spatial system and cellular automata, GeoCA model is brought forward as a general framework of cellular automata based model for simulating and analyzing complex Geo-Spatial system. GeoCA is a scheme for the study of Geo-Spatial system, through which profound principle can be explored. In addition, LUCC impacts on environment represent on regional climate, atmospheric quality, soil properties, water quantity and quality and so on. All researches discussed above are of great benefit to environment appraise and suitable layout of land.

Key words: GIS, LUCC, arid region