Effect and mechanism of environmental regulation improving the urban land use eco-efficiency: Evidence from China

Due to high pollution and low eco-efficiency of urban land use, the sustainable development of urban economy and ecology is restricted. Environmental regulation (EnR) is essential for the government to guide the ecoefficient use of land resources, solve environmental problems, and promote ecological civilization construction. Utilizing a dataset comprising 266 cities in China from 2011 to 2021, this paper studies the intermediary effect of green technology innovation (GTI) and industrial structure optimization (ISO) in EnR affecting urban land use eco-efficiency (ULUEE). The results show that: (1) The EnR significantly promotes the improvement of ULUE, reaching 0.354; (2) EnR also promotes GTI and ISO to 0.653 and 0.189, respectively; (3) From the results of mediating effect, GTI and ISO are mediating variables that affect the level of ULUEE. GTI also affects ULUEE through ISO. From the perspective of the path coefficient of the chain mediating effect, the influence coefficient of path(1) (EnR -> GTI -> ULUEE) is 0.107, path(2) (EnR -> ISO -> ULUEE) is 0.111, and path(3) (EnR -> GTI -> ISO -> ULUEE)) is 0.043; (4) There is an inverted U-shaped relationship between the effects of EnR on ULUEE; (5) In the heterogeneity analysis, the effect of EnR on ULUEE is more evident, but the impact is less pronounced in eastern cities and large cities of scale.