Study on urban niche taking the urban agglomeration in northern slope of tianshan mountains as a case

In this paper, the authors define the conception such as urban niche at the beginning, based on the niche theory. Taking urban agglomeration in Northern Slope of Tianshan Mountains as a case then, the niche breadth model and differentiation index model are used to analyze the breadth and structure changes of urban niche, and the interaction relations between each other in the urban agglomeration. The main data used in this paper include demographic data, industry figures and investment data from 1980 to 2010. According to the analysis, it shows that: 1 In the urban agglomeration, the population niche of Urumqi and Shihezi are higher than other cities, while the economic niche and resource niche of Urumqi and Karamay are the two front-runners. It indicates that urban niche is incontinuous. 2 As to economic niche, the niche breadth of city with maximum value is 32 times bigger than the city with the minimum in the urban agglomeration, which indicates that the difference of niche breadth within the urban agglomeration 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 indicate 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 the urban agglomeration is gradually transforming from single-center into multi-center urban agglomeration. According to the characteristics of cities in the Northern Slope of Tianshan Mountain and the requirements of the specialization and cooperation, the idea of dislocation development in allusion to the urban agglomeration is put forward at last.