摘要
利用元胞自动机模型进行城市扩张模拟时,其使用的栅格数据格式和基于统计的转换规则提取方法必然会导致可变面积单元问题(the Modifiable Areal Unit Problem,MAUP)的出现。采用系统的敏感性分析方法对该问题的粒度效应、划区效应和综合效应进行了分析,研究表明:1)MAUP问题在CA模拟时是客观存在的,且会对模拟结果造成影响,研究时不能忽视该问题。应进行系统的敏感性分析,获取其对研究问题的影响,寻找适宜的研究粒度和分区方案。2)该研究中粒度效应会呈现明显的尺度阈值,尺度域内的拟合优度和模拟精度较为稳定。尺度阈值在最精细粒度后随即出现,且该阈值与景观指数的尺度阈值一致,反映了景观对象大小对城市扩张模拟的重要影响。3)良好的划区方案能够提高拟合优度和模拟精度,其划区方案应使区域内城市扩张规律差异最小,区域间城市扩张规律差异最大。在大尺度城市扩张模拟时更应采用合理的划区方案以提高模拟精度。4)粒度效应和划区效应的综合影响表现为各区域模型的拟合优度和模拟精度在粒度范围内所受到的影响存在差异,但大多数区域都较为明显地表现出相同的尺度阈值。
When using cellular automata as a simulation model of urban expansion, the raster data format and the extraction of conversion rules based on statistical methods w ill inevitably lead to the MALP （the M odifiable Areal Lnit Problem）. A systematic sensitivity analysis has been used to get the scale effect, zoning effect and combined effect on simulation results. The results show that： 1） The MALP in CA model simulation is an objective reality, the simulation results will be affected, and it cannot be ignored. Systematic sensitivity analysis should be carried out to get its impact on the research questions and find the proper grain and partition sdieme.2） The scale effect shows a significant scale threshold, goodness of fit and simulation accuracy is stable along the scale domain. Scale threshold appears after the finest grain, and is consistent with the scale threshold of the landscape. This reflects an important insight that the urban sprawl process is related to the size of landscape objects. 3） Better zoning scheme can im prove the goodness of fit and simulation accuracy, and the zoning plan should have minimal differences on rules of urban expansion within the region, and the largest differences among the regions. This is an essential problem that should be considered in large- scale urban expansion simulations. 4） The combined effect shows different effects on different regions, but there are the same scale threshold for most regions.
出处
《地理与地理信息科学》
CSCD
北大核心
2016年第5期14-21,127,共9页
Geography and Geo-Information Science
基金
国家自然科学基金青年科学基金项目(41301443)
