中国城市建设用地集聚对利用效率的影响:机理、空间效应与分群差异

为探究城市建设用地集聚对城市建设用地利用效率的作用机理,文章基于2003—2017年中国278个地级及以上城市面板数据,通过构建多产出随机前沿生产函数模型测度城市建设用地利用效率,采用时间-空间双固定的空间杜宾模型探讨了不同程度的城市建设用地集聚对利用效率的影响机理与差异。结果表明:(1)从时空特征上来看,样本考察期内中国城市建设用地利用效率总体上呈稳步提升趋势,东部城市建设用地效率最高,西部次之,中部最低。(2)从全国维度的空间计量模型回归结果来看,城市建设用地集聚所带来的规模效应和外溢效应对城市建设用地利用效率具有改进作用,有利于利用效率进一步提升。(3)从不同城市建设用地集聚度分群回归结果来看,高集聚城市(东部发达地区)的直接效应显示随着城市建设用地集聚度的提高,利用效率也不断提高;间接效应中,建设用地集聚度的提高对周边城市的利用效率产生先带动后抑制的"倒U"形作用。低集聚城市(中西部欠发达地区)的直接效应和间接效应均显示,随着城市建设用地集聚的提高,其利用效率存在"先降后升"的"U"形曲线特征。可见,在城市发展的不同阶段,城市建设用地集聚对城市土地利用效率存在差异化影响。因此,中国城市发展应立足当前发展阶段特征,制定差别化的供地政策,促进城市建设用地集聚,针对性地提升区域要素利用效率,支撑经济社会进一步发展。

Impact of urban construction land agglomeration on land-use efficiency:mechanism,spatial effects and group differences

In order to examine the effects of urban construction land agglomeration on urban construction land-use efficiency,this paper adopted the stochastic frontier method to measure the urban construction land-use efficiency,based on the panel data of 278 cities in China from 2003 to 2017.The varied influence mechanisms of different degrees of urban construction land agglomerations on landuse efficiency were studied based on double fixed spatial Durbin model.The results showed that:(1) From the perspective of spatio-temporal characteristics,the urban construction land-use efficiency in China generally reflected a trend of steady improvement during the study period,with the highest in the eastern region,followed by the western region and the lowest in the central region.(2) Based on the regression results of national data,the scale effect and spillover effect induced by urban construction land agglomeration could improve the utilization efficiency of urban construction land.(3) Based on the analytical results of different groups,the direct effect of the highagglomeration cities(in the eastern developed region) implied that the improvement of urban construction land agglomeration could enhance the land-use efficiency.For the indirect effect,the promotion of construction land agglomeration in a city had an inverted Ushaped effect on the land-use efficiency of the surrounding cities.The direct and indirect effects of low-agglomeration cities(in the less developed regions in central and western China) indicated that the land-use efficiency was characterized by a U-shaped curve,accompanying with the improvement of urban construction land agglomeration.The results suggest that urban construction land agglomeration has a differentiated impact on urban land-use efficiency in different development periods.Therefore,policymakers should formulate differentiated land supply policies based on the characteristics of current development period in order to improve the urban construction land agglomeration.Moreover,policymakers should take targeted measures to enhance regional utilization efficiency of land in order to further sustain socioeconomic development.