Research On Simulation Of Urban Expansion,Cultivated Land Protection And Wetland Loss Bassed On Agent-based Model

Staying in a accelerating stage of urbanization, China’s socio-economic development have highly been aggregating, which leads to the rapid expansion of urban land occupying cultivated land and even wetland. And the expansion would encroach more and more ecological land, especially wetland under the double target of urban development and cultivated land protection. Besides, the process and driving factors of urban expansion is so considerably complicated that tranditional research methods can hardly be applied to make a comprehensive analysis on the factors, particularly the facors on socio-economic and humanity. Consequently, it is necessary to combine Cellular Automata (CA) and Agent-based Model (ABM) to simulate the actual urban expansion more accurately, so as to investigate the mechanism of action of decisions interaction on the relationship of urban expansion, protection of cultivated land and the loss of wetland, which would provide reference for urban management, urban plannin, sustainable and coordinated development and so on.In this paper, the basic relevant theory of cellular automata and agent-based model are described in the first part, togethor with the application on urban expansion research of the combination of the two. Secondly we analyze the evolution of pattern of urban expansion-cultivated land protection-wetland loss from the aspects of land use structure, land use degree and land use spatial pattern. The we establish the model of urban expansion simulation, with CA and ABM, and select the optimal model through the comparison of various models to imitate the urban expansion under the governments with different charactristics, based on which we study the influence on clutivated land and wetland loss of urban expansion. Finally, we research the mechanism of action of decisions interaction of diverse microcosmic agents as a factor contributing to the relationship of urban expansion, protection of cultivated land and the loss of wetland.The results show that the highest accuration exsits in the CA-ABM model with all the three agents of government, developers and peasants. Furthermore, the interreaction of urban expansion, protection of cultivated land and the loss of wetland evolves with the change of decisions interacion of the three agents.