城市群多中心性与绿色发展效率——基于异质性的城镇化空间布局分析

城市群是城市的空间组合,是中国推进新型城镇化和践行绿色发展理念的主要空间载体,其多中心性是否有利于提升区域绿色发展效率和实现协调发展?文章利用夜间灯光数据测度了城市群的多中心性,将三大污染排放指标作为非期望产出计算了Malmquist-Luenberger动态分解指数以考察城市群绿色发展效率的跨期变化。基于2004—2018年14个重点城市群的面板数据,实证研究了城市群的多中心性对成员城市绿色发展效率的影响。研究发现:(1)城市群多中心性对成员城市的绿色发展效率存在显著的门槛效应,且东部城市群的多中心性对成员城市的绿色发展效率起到促进作用,而中部和西部城市群的多中心性则对绿色全要素生产率起到抑制作用;(2)城市群多中心性对中间位序城市的绿色发展效率产生负面效应,但是对首位城市和位序靠后的城市产生正面效应,且该效应随城市经济位序后延而递减;(3)城市群多中心性对绿色发展效率产生先促进后抑制的作用,传导机制评估发现,城市群多中心性对成员城市绿色发展效率的“倒U型”影响主要是通过知识溢出、科技创新和人力资本水平起作用。更改多中心指标、采用地形起伏度和1933年的铁路通车数据作为工具变量、更改方法为面板Tobit模型重新进行估计得到的结果没有实质性改变。基于上述发现,现阶段中国城镇化空间布局重在发展大城市和小城市之间的权衡,应综合考虑空间单元异质性,制定和实施差别化的城市群政策。

我国城市群建设的成效、问题及对策研究

党的十八大以来,城市群建设取得重大进展,日益成为承载发展要素的主要空间形式,对完善城镇化战略格局、优化区域经济布局、推动高质量发展发挥了重要作用。当前,部分城市群存在人口和经济集聚能力不强、产业发展呈现同质化竞争、核心与边缘地区发展差距进一步拉大、无序蔓延扩建新城新区和毗邻合作区等问题,导致这些问题的深层次原因包括城市群空间范围缺少统一科学的划定标准、跨行政区一体化体制机制建设滞后、行政区划等级分割影响较大、缺乏明确的治理主体等。针对突出问题,建议分类施策、深化改革、增强引导、创新机制、加强监测,有序引导促进城市群高质量发展。

Research on Newly Urbanized Towns and Districts in China

Since the last decade the central government endeavors to promote large scale of urbanization in China.Lots of new urban towns and districts are taking shape. Outline of the 12th Five-year Plan released by the central government points out that the new towns and districts are to be regulated. But few researches are considering the new towns and districts especially in the spatial distributive pattern and status in China. Given this situation this paper, after sorting out the world-wide research and development of new urban towns and districts, gives definitions of broad and narrow meanings. Based on the broad meaning definition, the database of new towns and districts in China is established. This paper then conducts a preliminary analysis of the new towns and districts.Then the two-step work plan and the advices are also proposed to further improve the research and practice of its kind in China.