Revealing the spatial differences and convergence mechanism of urban land use efficiency (ULUE) under the background of regional integration is of great significance for exploring the coordinated promotion path of ULUE. We attempted to build a theoretical framework to interpret ULUE spatial convergence under the background of regional integration and build a ULUE “green” evaluation system under multi-objective constraints. Based on this, we employed the super efficiency slack-based model (SBM), exploratory spatial data analysis, and spatial convergence model incorporated into the spatial weight matrix to re-examine the true level, spatial differences, and convergence mechanism of ULUE in the Yangtze River Economic Zone from 2003 to 2019 on a city scale. The results show that: (1) during the investigation period, ULUE in the Yangtze River Economic Zone has obvious spatial disequilibrium and spatial correlation characteristics; (2) there are absolute β-space convergence and conditional β-space convergence of ULUE in the whole Yangtze River Economic Zone and its upstream, midstream, and downstream areas; (3) driven by government management, industrial development, and spatial error effects, the convergence time of ULUE in the whole Yangtze River Economic Zone and its upstream, midstream, and downstream areas is obviously shortened.

This paper theoretically constructs the logical framework of urban agglomeration affecting urban land green use efficiency (ULGUE) and employs the super efficiency SBM model with undesired outputs to measure ULGUE based on the research object from 107 prefecture-level cities and above in the Yangtze River Economic Zone. Then, this paper uses the difference-in-differences method to test the impact of urban agglomeration on the ULGUE. The results show that: (1) urban agglomeration has a positive regulatory effect on the ULGUE, and this research conclusion is robust; (2) the promotion effect of urban agglomeration on the ULGUE has regional differences, showing the basic pattern of ordinary prefecture-level cities > regional central cities > provincial capital cities and medium cities > big cities > super large and megacities; (3) small and medium-sized cities should be encouraged to further agglomerate while moderately controlling the excessive agglomeration of super-large cities and megacities. Moreover, it is suggested to improve the level of regional agglomeration from the aspects of flexible use of market mechanisms and policy tools, innovative technology applications to achieve the effective integration of urban agglomeration, and ULGUE promotion.

It is of great significance to explore the dynamic coupling relationship between industrial integration and urban land-use efficiency (ULUE) in order to promote high-quality urban development. This paper presents a system for evaluating industrial integration and ULUE which combines the internal theoretical relationships between the two. Based on this system, this paper analyzes the evolution process and the mechanism behind the coupling coordination relationship between industrial integration and ULUE with the help of the coupling coordination model, nonparametric kernel density estimation, and the geographical detector method. The results indicate the following: (1) The coupling coordination relationship between industrial integration and ULUE in the Yangtze River Economic Zone experienced an overall steady increase during the investigation period. However, there were great spatial differences in the coupling coordination relationship among cities. (2) The lag of the industrial integration level was the key area of resistance to the improvement of the coupling coordination level. (3) The interaction between industrial integration and ULUE in the Yangtze River Economic Zone was very significant. In particular, the impact of industrial agglomeration and factor flow on the ULUE and the impact of land on industrial integration in terms of ecological environment were prominent. In addition, the interaction of different detection factors was mainly manifested as a double factor enhancement effect and nonlinear enhancement effect.

Based on the panel data of 257 prefecture-level cities in China from 2010 to 2017, this paper measured urban land green use efficiency (ULGUE), incorporating undesirable outputs, via the super efficiency slack-based model (SBM). It also explored the effect, mechanism, and heterogeneity of growth targets management and regional competition on ULGUE via the time-varying gravitational spatial weight matrix and the spatial self-lagging model. The results show that growth targets management and regional competition have significant positive effects on ULGUE, and enhance the ULGUE by promoting local investment attraction, increasing innovation inputs, optimizing environmental regulations and strengthening commercial activities. Additionally, growth targets management has a more significant effect on eastern cities, non-central cities, and mature urban agglomeration, while regional competition has a more significant effect on central cities, non-central cities, and developmental urban agglomeration. Therefore, considering development as the priority, setting relatively aggressive economic growth targets and optimizing the regional competition mechanism for growth targets management can help improve the ULGUE and promote high-quality economic development in China.

The green transition of farmland use is a future trend in China’s modern agriculture and green development. However, its research framework, including its evaluation system, temporal-spatial distribution, and driving mechanisms, has not been established in the existent literature. With the 17 cities in Hubei Province as an example, we evaluated the green transition of farmland use and explore the characteristics and driving mechanisms of the temporal and spatial evolution from 2000–2019. The findings were as follows: First, the green transition of farmland use in Hubei Province is in infancy, but it has great potential. Second, the growth rate of the green transition of farmland use has noticeable regional differences in the east, central, and western areas of the province. Third, the three dimensions of spatial transition, functional transition, and model transition in the green transition of farmland use have significant spatial differences in coupling and coordination, and decoupling is becoming increasingly prominent. Based on the research findings, we put forward targeted countermeasures and suggestions.