2000 年来中国人口地理演变的Agent 模拟分析

以基于自主体模拟为建模工具。建立了包含气候、农业、社会影响因素的中国2000年来人口地理演变模型。基于该模型对南北人口格局的转变、东西人口格局（即胡焕庸线）的形成以及2000年来全局人口分布演化的动力机制做了分析。研究结果表明：在不考虑气候变化、农业生产潜力波动以及社会因素影响的情景下，中国各省人口模拟值与实际值的相关系数达到0．9733，省区间初始农业生产潜力差异决定了人口的基本分布状态，是人口分布特征的内在因素．对人口地理演化具有深远的影响：中国人口分布南重北轻的人口分布格局发生在910年代左右．以安史之乱导致的战祸和动荡的社会条件为主要演化动力：胡焕庸线中国人口东西部分布格局形成于1235-1255年代左右，以1230-1260A．D．的气候突变为该人口分布特征线形成的主要动力：气候变化对2000来历史人口分布的全局演化过程中起了主导驱动作用，在单影响要素的情景中，气候变化对全局人口分布形成的贡献率最大，为0．9869，进一步，气候变化对人口地理演化的影响以1230-1260A．D．的气候突变为转折点表现为阶段性差异。

Agent- based Simulation on the Evolution of Population Geography of China during the Past 2000 Years

In order to simulate the evolution of population geography of China during the past 2000 years, an agent-based model is presented in this paper. In the model, population individuals are denoted as agents and geographical environment is presented by cellular automata. Agents can migrate or settle in cellular influenced by historical climatic, agricultural and social conditions which are tightly integrated with population system. With model construction, the formations of population distribution pattern in north vs. south and east vs. west are simulated, as well as the evolution of holistic population geography. Additionally, the driving forces for those population geography developments are investigated respectively. Results are as followings: 1) Even when all the climatic, agricultural and social disturbances are neglected, the correlative coefficient between the simulated population of each province and the realistic data reaches 0.9733. The result shows potential agricultural productivity makes far-reaching influence on China's population geography, determining the essential characteristic of population distribution. 2) Among the scenarios which take account of solo influence, it is found that climatic change made greatest contributions to the evolution of holistic population geography with a contribution coefficient of 0.9869. Therefore historical climate change is proved to be the main driving force for the entire evolution of population geography since 2 A.D. Further, we found that the influence of climate change is multi-phased taking the drastic climate change in 1230-1260 A.D. as a turning point. Before that climate change works faintly on population distribution, but become forceful after that. 3) Based on simulation, it is discovered that the pattern of population geography in north-south China shaped during 910 A.D.'s mainly driven by the social unrest as Anshi turmoil at that time. Because of the turmoil, millions of populations in the north move to the provinces in the south to avoid the war. 4) The pattern of population geography in east-west China is shaped during 1235-1255 A.D. Considereing the temporal social and climatic conditions, we figure the drastic climate change in 1230-1260 A.D. would be the main driving force for the formation of population distribution in east-west China.