Simulation Research On Urban Construction Land Expansion Based On Urban-ABM

Urbanization is an inevitable phenomenon of social development.Since the reform and opening up,China’s cities have developed rapidly.However,problems such as traffic congestion,environmental pollution and blind expansion with urbanization have become increasingly prominent,which has a major impact on the sustainable development of cities.Urban expansion is greatly influenced by human behavior,and the multi-agent model is from the perspective of “human”,simulating the influence of people’s behavioral decision-making on urban expansion,and “bottom-up” simulating the dynamic process of urban expansion to explore the process of urban expansion.The role and influence mechanism of the main body contributes to the green and healthy development of the city.This paper takes the urban area of the Chuxiong as the study area.Based on the land use data from 1990 to 2015,this paper analyzes the changes of construction land in the study area from three aspects: expansion speed,expansion intensity and expansion space pattern.The multi-agent layer and the environment element layer were analyzed,and the corresponding behavior decision rules were formulated,and the construction behavior of the main body was added.With the support of the ArcGIS platform,the urban expansion simulation program(Urban-ABM)was built using the Python programming language and the GDAL module,and the Urban-ABM was applied to simulation program simulates the construction land in the study area and predicts the distribution of construction land in the study area in 2025 under different scenarios.The main study contents and conclusions are as follows:(1)The spatio-temporal structure of land use in the Chuxiong City and the spatio-temporal structure of construction land in the study area were analyzed.The results show that the construction land mainly comes from cultivated land,and its change speed and amplitude are the largest,and the expansion speed is also continuously increasing.The expansion direction is first to the northwest and then to the southeast.(2)Construct a simulation model framework for urban construction land.Firstly,the environmental element layer and the multi-agent layer were analyzed,and the interaction between agents、agent and environment is expounded.On this basis,the behavior decision rules of the agent are constructed: the resident agent selects the location based on the maximum utility value;the developer agent development and construction based on development probability values and “build rate”;government agent have a limit role in the entire expansion process,including elevation,slope and road.In order to make the simulation more realistic,the construction behavior is added to the behavioral decision-making of developers and government agents.In the process of urban expansion,developers and government agents will conduct schools,shopping malls,transportation facilities and park squares and so on according to the scale of expansion to built.Since the study area is a mountainous area,the corresponding “buffering” analysis was performed on its elevation and slope.(3)The writing and application of the Urban-ABM simulation program.Based on the urban construction land simulation model framework,the Urban-ABM simulation program is written using the Python programming language and the GDAL module.The application of this program was used to simulate the construction land expansion in the study area from 1990 to 2010.The simulation results were in good agreement,and the simulation accuracy was 70.4%.Based on the land use data of the study area in 2015,the expansion of construction land in the study area in 2025 under different scenarios is predicted.