土地经济密度的区域差异特征及动态演变格局——基于长江三角洲地区的实证分析

基于长江三角洲地区25个城市的土地经济密度数据，利用泰尔指数、空间自相关等方法对1995-2007年长江三角洲地区土地经济密度的区域差异特征及动态演化格局进行了初步探索。研究表明：①该区域的土地经济密度总体呈不断上升趋势，但是城市间差异明显，其高值点主要集中于沪苏锡常地区；②土地经济密度的总体差异和区间差异呈现波动性缩小趋势，江苏省内部差异和区间差异是总体差异的主要组成部分；③土地经济密度总体上趋于空间集聚，但局部的空间集聚中心从环杭州湾城市转移到苏南地区和上海。可见，高投入、低效率的土地利用方式已不适合长江三角洲地区的发展，未来必须统筹区域土地利用，合理配置土地资源，促进区域合理分工和协调发展。

Regional Disparity and Dynamic Evolution of Land Economic Density-Evidence from the Yangtze River Delta Area

With rapid development of urbanization in China, the contradiction between economic growth and urban land supply is increasingly conspicuous. To solve this problem and achieve socio-economic sustainable development, we must increase land use efficiency. This essay investigated the regional disparity and dynamic evolution patterns of land economic density of the Yangtze River Delta from 1995 to 2007, by using methods including Theil index and spatial autocorrelation. This study indicated three conclusions. First, generally the land economic density of the Yangtze River Delta tended to increase continuously. In 2007, there were seven cities whose land economic density were higher than the average level, while 18 cities had lower land economic density than the average level. The peak values of land economic density concentrated in Shanghai, Suzhou, Wuxi and Changzhou. Second, both the overall and interregional disparities of land economic density were shrinking with volatility; but the regional internal disparity continued to widen. The internal disparity continued to widen in Jiangsu province, but tended to lessen in Zhejiang province. Due to the enlargement of internal disparity in Jiangsu province, the internal disparity contribution ratio to the overall disparity was increasing from 38.25% to 54.2%. Meanwhile, the internal disparity in Jiangsu province and interregional disparity were the main components of the overall disparity. The relative development rate of land economic density was higher in southern Jiangsu than in northern and central Jiangsu as well as most parts of Zhejiang. Finally, the tendency of spatial concentration was obvious in the whole area, but local spatial cluster centers had shifted to southern Jiangsu and Shanghai from cities around Hangzhou Bay. Meanwhile, northern Jiangsu was always an area with low land economic density, and southern Zhejiang had no significant changes in spatial pattern. This kind of disparity in the Yangtze River Delta showed that the land use pattern with high input and low efficiency was no longer suitable for the development of the Yangtze River Delta. Therefore, we must integrate regional land use and allocate land resource properly to promote harmonious regional development.