经济集聚扩大绿色经济效率差距了吗?——来自黄河流域城市群的经验证据

Does economic agglomeration widen the efficiency gap in green economic efficiency? Evidence from urban agglomerations in the Yellow River Basin

城市群经济集聚和绿色转型作为区域经济发展的基本表现和现实诉求,二者能否"珠联璧合"备受关注。基于空间均衡模型理论剖析城市群经济集聚与绿色经济效率及其不平等现状的内在关联,进而选取黄河流域七大城市群作为研究样本,通过动态空间杜宾模型对二者的非线性关系与空间溢出效应进行考察,同时对作用路径和溢出机制给予关注。为了解决城市群经济集聚与绿色经济效率的双向因果关系引致的潜在内生性问题,选取地形起伏度和明代驿站设立作为专门的工具变量。研究发现:黄河流域城市群经济集聚与绿色经济效率存在倒U型关系,经济集聚处于合理的范围内有助于提升绿色经济效率,而当经济集聚过度时则会抑制城市群绿色经济效率提升;城市群经济集聚会扩大群际绿色经济效率差距从而加剧其绿色发展的不平等;城市群经济集聚对绿色经济效率具有显著的正向空间溢出效应,且这一溢出效应存在典型的地理距离衰减特征,400km~500km处溢出效应分布密集;绿色技术创新和劳动力市场高级化是城市群经济集聚影响绿色经济效率以及群际差距的重要路径和溢出机制。

Economic agglomeration and green transformation of urban agglomerations are the basic manifestation and realistic demand of the regional economic development. Whether the two can combine together has attracted much recent attention. This paper conducts theoretical analysis based on the spatial equilibrium model, further uses the Dynamic Spatial Durbin Model to assess the impact of economic agglomeration on the green economic efficiency gap and its spatial spillover, with the research samples that seven major urban agglomerations in the Yellow River Basin. Meanwhile, the paths of action and spillover mechanisms are also investigated. To solve the endogenous problems caused by potential two-way causality, topographic undulations and the establishment of Ming Dynasty Station are selected as instrumental variables. The results show that the relationship between the economic agglomeration of urban agglomerations in the Yellow River Basin and green economic efficiency presents an inverted-U shape, indicating that reasonable economic agglomeration can help improve the green economic efficiency, while excessive economic agglomeration can hinder the improvement of the green economic efficiency. Economic agglomeration of urban agglomerations can widen green economic efficiency gaps among urban agglomerations, exacerbating inequality in green development. Moreover, economic agglomeration has a significantly positive spatial spillover effect on green economic efficiency with typical geographical distance attenuation, and this effect is densely distributed at 400 km~500 km. The green technological innovation and advanced labor market are also important paths and spillover mechanisms for urban agglomeration economic agglomeration to affect green economic efficiency and inter-group gaps.