城市生态位测度研究——以天山北坡城市群为例

Urban niche metrics:a case of the urban agglomeration in Northern Slope of Tianshan Mountains

依据生态位理论,界定了城市生态位等相关概念。以天山北坡城市群为研究对象,选取1980-2010年人口、产业和投资等数据,根据城市生态位宽度模型、分异指数模型和重叠指数模型,分析了该城市群中各城市生态位空间宽度、生态位结构变化及其相互作用关系,为实现城市群的持续发展提供了新视角。结果表明:天山北坡城市群中,乌鲁木齐和石河子的人口生态位较大,而在经济生态位及资源生态位方面乌鲁木齐和克拉玛依位居前两位,说明城市生态位具有不连续性特征。天山北坡城市群中经济生态位宽度最大值的城市是最小值城市的32倍,说明天山北坡城市群中城市生态位宽度的差异悬殊。同时,天山北坡城市群的人口、经济及资源生态位分异指数均呈现下降趋势,人口与经济要素在空间上的不平衡得以改善,城市之间人口、经济发展的差距在逐渐缩小。天山北坡城市群正逐渐由"单中心"城市群向"多中心"城市群演进。在城市生态位重叠指数方面,城市之间的重叠指数呈现不断增大趋势,说明天山北坡城市之间的产业结构趋同性增强,同质竞争日趋激烈。针对天山北坡城市群城市生态位特征,按照专业化分工协作的要求,提出了城镇组团错位发展的设想。

This paper defines the conception of urban niche at the beginning, based on the niche theory. Aand then Taking urban agglomeration in Northern Slope of Tianshan Mountains as a case, the niche breadth model, differentia tion index model and overlap index model are used to analyze the urban ecological space, niche structure changes and the interaction relations between each other in the urban agglomeration. The main data used in this paper in clude demographic data, industry figures and investment data from 1980 to 2010. According to the analysis, the re suits show as follows ： （ 1 ） In the Northern Slope of the urban agglomeration, the population niche of Urnmqi and Shi hezi are higher than other cities, while the economic niche and resource niche of Urnmqi and Karamay City are the two front-runners. It indicates that urban ecological niche is uncontinuous. （2） As to economic niche, the niche breadth of city with maximum value is 32 times bigger than the city with the minimum in urban Northern Slope of Tianshan Mountains, which indicates that the difference of niche breadth agglomeration within the urban agglom eration is huge and the polarization effect of central city is prominent in aspect of economic and social development. （3） The population, economic and resource niche differentiation indices show the downward trend, which indicates that the spatial imbalance of population and economy are improving and the gap between population and economic development is gradually diminishing. It also means that urban agglomeration in the Northern Slope of Tianshan Mountains is gradually transforming from single-center into multi-center urban agglomeration. （4） The city niche overlap indices indicate an increasing trend, which reveals that the convergence of industrial structure is increasing Northern Slope of Tianshan Mountain and the requirements of the specialization and cooperation, the idea of disloca tion development in allusion to the urban groups is put forward at last.