转型期京津冀城市群时空扩展及其动力机制研究——基于夜间灯光数据的视角

Metropolitan region has become the most dynamic area and the most competitive area of China. However, it also emerged many structural problems such as economic imbalances, spatial imbalances and uncontrolled ecological problems after experiencing dramatic expansion since 1978. Re-examining the characteristics and basic logics of metropolitan spatial-temporal expansion in a transition era should be paid more attention by urban geography field. In this study, nighttime light data is used to analyze spatial-temporal patterns and its driving mechanisms of metropolitan region through a series of data processing, such as making data compatible, continuous calibration, extraction of urban area. In conclusion, this study builds a set of technical methodology of using nighttime light data to analyze metropolitan expansion of long-term and large scale which can overcome the drawbacks of high-resolution remote sensing data and statistical data of built-up area. Also, this study reveals metropolitan driving mechanism and basic logic compared with these in metropolitan regions of western developed countries and metropolitan regions in developing countries at the beginning of transition era which can be used to give planning guidance to metropolitan spatial governance.

城市群已成我国最具发展活力和竞争力的区域，在经历了改革开放后长达30多年剧烈空间扩展后，我国城市群发展出现了经济失调、空间失衡、生态失控的结构性难题，重新审视转型期城市群时空扩展的路径特征及其基础逻辑，是城市地理学急需关注的重大科学命题。本研究创新性地采取夜间灯光数据，以城市群为例，通过数据兼容校正、连续校准、阈值提取等数据处理技术，利用时空格局模型研究城市群时空扩展的路径及特征，探讨驱动城市群时空扩展的内在机理。在研究方法上，克服了高分辨率遥感影像数据和建成区统计数据在研究长时段、大尺度区域城镇时空扩展的弊端和缺陷，构建利用以夜间灯光数据研究城市群城镇时空扩展的技术方法体系。在理论架构上，揭示了转型加速期城市群城镇时空扩展的演进机理和基础逻辑，并与西方市场经济主导下城市群时空扩展路径和转型初期发展中国家城市群时空扩展路径进行对比分析，为城市群空间管治和调控提出科学的政策和规划指导。

城市群已经成为我国城镇化发展重要空间载体，研究其时空演化逻辑和动力机制对于引导其健康发展具有重要意义。针对中西方关于城市群空间扩展路径研究的争论，以京津冀城市群为例，运用夜间灯光数据，采取扩展强度指数、空间关联模型、多维驱动力分析模型，定量揭示了城市群时空扩展路径及其动力机制。结果表明：① 1992-2012年京津冀城市群时空扩展呈现以京津唐为核心的中心集聚扩展模式，保定—衡水—石家庄之间的“三角地带”成为城市群空间扩展的冷点区；② 城市群空间扩展虽然已经出现了扩散势头，但向心集聚的惯性作用力依然强大；③ 城市群时空扩展的动力机制表现出以市场力为主要驱动因子的特征，行政力、外向力和内源力对城市群空间扩展的影响作用依次递减，从城市群空间扩展的驱动力演化趋势看，市场力、行政力、外向力的影响呈现上升趋势，而内源力的影响系数则呈现下降趋势。最后，提出降低行政干预、构建市场主导机制、强化内外双向开放、推动产业升级的政策建议，促进城市群空间结构持续优化。