FROM PROCESS TO PATTERN IN LUCC-AN AGENT-BASED MODEL OF AGRICULTURAL LAND USE CHANGE BY COUPLING WITH GIS

摘要

This paper presents an agent-based model for simulating changes in sown areas of four crops at a global seale. Its basic hypothesis was that decisions on crop choice made by farmers m ediated the im pacts of biophysical and socio-econom ic aspects on changes in agricultural land use. To do this, a Logit m odel was adopted to track the crop choice decision behaviors of land user by using a crop utility function. The crop utility was explained by four independent variables: crop yield, rural population density, road accessibility and crop price. Of these, crop yield, which represents biophysical factors, was simulated from the GIS-based EPIC model and crop price, which repr esents the socio-econom ic vari ables, was estim ated by the IFPSIM model. This agent-based model was used to simulate future scenarios over a time frame of 30 years with a 5-year increm ent, beginni ng from the year 2000. The simulation results provided insights into potential global cropping patterns, variation in rate sand trajectory of changes in sown areas for m ajor crops over the test period. These results can im prove understanding of projected la nd use changes and explain their causes, locations andconsequences, and provide support for land use planning and policy making.