黄河流域城市生态效率演化特征及门槛效应

基于非期望产出视角测度黄河流域城市生态效率，探讨2003—2017年黄河流域城市生态效率时空演化特征及资源禀赋的门槛效应。结果表明：① 黄河流域城市生态效率呈稳步上升态势，但全域和资源型城市表现出一定梯度效应，有两极分化现象；② 各城市生态效率总体呈东高西低、南高北低格局，并存在显著空间溢出效应，不同类型城市演化存在显著的时空惯性。③ 资源禀赋存在显著门槛效应，资源型城市生产性服务业集聚与生态效率呈“U”型关系，制造业集聚在跨过门槛值后会产生抑制作用，产业协同集聚则始终具有正向作用；非资源型城市资源禀赋会削弱生产性服务业集聚的促进作用，制造业集聚及产业协同集聚的影响跨过门槛值后不显著。

The Evolution Characteristics and Threshold Effects of the Ecological Efficiency in the Yellow River Basin Cities

This article studies the urban ecological efficiency of the Yellow River Basin, and discusses the spatial-temporal evolution characteristics of urban ecological efficiency and the threshold effect in the Yellow River Basin from 2003 to 2017 based on the perspective of unexpected output. The results showed that: 1) The ecological efficiency of the Yellow River Basin cities increased steadily, but the whole region and resource-based cities showed a certain gradient effect, with polarization phenomenon. 2) The ecological efficiency of each city is higher in the east and lower in the west, higher in the south and lower in the north, and there is a significant spatial spillover effect. 3) Resource endowment has a significant threshold effect. For resource-based cities, the relationship between producer services agglomeration and ecological efficiency is U-shaped, manufacturing agglomeration will have inhibitory effect after crossing the threshold, and industrial collaborative agglomeration always has a positive effect. For non resource-based cities, resource endowment will weaken the promoting effect of producer services agglomeration, while the influence of manufacturing agglomeration and industrial collaborative agglomeration is not significant after crossing the threshold.