基于经济联系强度的乌鲁木齐都市圈空间结构研究

Study on Spatial Structure of Urumqi Metropolitan Area Based on Economic Relation Intensity

从经济联系强度的角度出发,运用分形理论对乌鲁木齐都市圈的空间结构进行研究,计算了都市圈内城市间经济联系强度。对比分形的自相似特征,分析了都市圈经济联系强度的空间分布情况,指出都市圈存在中心城市辐射力不足、对其他城市发展带动力弱等问题。结合产业的相似度,探讨了提高中心城市经济辐射力的优化方案,结果表明乌鲁木齐、米泉市、昌吉市作为一个经济区统一规划,经济联系强度分维值是以乌鲁木齐市为中心的近2倍,都市圈空间结构明显优化。在对优化方案进行深入分析的基础上,发现乌鲁木齐都市圈经济联系强度扩散的空间特征:(1)中心城市的经济辐射能力以及周边地区对中心城市经济辐射力的接受能力,随距离增加呈现出按指数函数衰减;(2)梯度扩散与城市的等级规模有关,城市等级规模小,对经济辐射的接受能力弱,可能出现跃迁现象。在经济扩散过程中,两种特征同时并存,前者占主导地位。

Based on fractal theory, spatial structure of Urumqi Metropolitan Area is studied; and the economic relation intensities amongst different cities and counties are calculated. In comparison with self-affine fractal characteristics, the spatial distributions of economic relation intensity are analyzed. It is pointed out that the radiation of central city is weak. Combined with degree of industries＇ similarity, measures of optimization are discussed. It shows that Urumqi, Miquan and Changji are melt into one economic region, and fractal dimension of economic relation intensity is nearly as twice as that of centre in Urumqi. The spatial structure of Metropolitan Area can be further optimized. Based on analysis of optimized plan, two characteristics are found： first of all, economic radiating power and the acceptability of cities around the core region present the law of decaying according to the exponential function with increase of distance. Secondly, gradient diffusion depends on city＇s rank and scale. Economic diffusion may bypass the cities whose ranks are low and reach the cities that from the core region but with higher ranks are farther. During the course of economic diffusion, two characteristics co-exist, and the former law is more manifest.