摘要：
The study of optimum population size based on urban comprehensive carrying capacity has always been a hot issue in population geography. With the accelerating of China's urbanization, the population is gather-ing continuously in the city while environmental pollution, traffic jams and other"city diseases"have become in-creasingly prominent. City sustainable development is restricted by social economic factors and natural resources factors which is an important guarantee to maintain the population quantity in the range of carrying capacity. The concept of UCC (Urban Carrying Capacity) provides a powerful theoretical basis and quantitative means for gov-ernment planning and calculating the optimum population size. As the political, economic and cultural center of China, the shortage of resources, traffic jam and deterioration of ecological environment are becoming more and more serious in Beijing. It's significant to determine the scale of optimum population for guiding the population floating and environment protection. However, the research results about optimum population scale of Beijing are few. Based on comprehensive carrying capacity, this paper constructed an appropriate population measure-ment model and synthetically analysed the scale of optimum population and carrying population of Beijing from 2004 to 2014. Results indicated that:(1) The scale of ecological carrying population which is in a state of popula-tion overload has an increasing trend;(2) Economic carrying population scale has been decreasing for 15 years. The output value of tertiary industry contributed most which reached 65.15% in 2014; (3)Resources carrying population scale is in a state of fluctuation while its overload rate increased year by year. The contribution of land resources carrying capacity is greater than that of water resources which reached 79.91%in 2014;(4) From 2004 to 2014, the optimum population size of Beijing decreased from 20.31 million to 15.51 million and start a demographic deficit in 2008. Considering its contribution factor, resource constraint has become the main factor hindering the development of Beijing, and the economic carrying capacity is the main driving force to maintain the appropriate population size. The conclusions of this study can provide a reference for the formulation of ratio-nal population management decisions and urban sustainable development planning.%北京作为中国的政治、经济和文化中心,资源短缺、交通拥堵和生态环境恶化等问题日益严重,确定其适度人口规模,对引导区域人口合理流动和环境保护具有一定的现实意义.本文基于综合承载力,对已有的适度人口模型进行了改进:利用主成分分析法和熵权法确定生态、经济和资源承载系统的权重;经济承载人口测算指标不局限于地区生产总值(GDP)这一单一指标;资源承载人口综合考虑了土地资源和水资源承载力.本文通过综合分析2004-2014年北京各项承载人口和适度人口,结果表明:① 生态承载人口规模在波动中有增长的趋势,由717.38万人上升至753.14万人,一直处于人口超载状态;② 经济承载人口一直处于富余状态,但规模由5297.18万人减少至3802.06万人.第三产业产值所承载的人口对经济承载人口的贡献最大,在2014年达到65.15%;③ 资源承载人口规模处于波动状态,2014年为139.61万人,超载率逐年增加.土地资源承载力对资源承载人口的贡献大于水资源,2014年贡献率达79.91%;④ 北京市适度人口规模从2004年的2031.15万人减少至2014年的1550.67万人,2008年开始出现人口赤字,且人口超载率逐年攀升.经济承载人口对适度人口贡献率维持在80%以上,生态和资源承载人口的贡献率平均值分别为14%和3%.人口资源压力指数在波动中有上升的趋势,从2004年的9.45上升至2014年的15.41,资源约束已经成为阻碍城市发展的主要因素,经济承载力是维持适度人口规模缓慢减小的主要动力.
