Introduction: Urban green space is one of the most closely related ecosystem services to residents’ lives, and it can be regarded as a preventive public health measure. Residents living in parks and other green environments can help improve their physical and mental health, reduce stress and even prevent crime and violence. Therefore, based on the actual situation in China, this paper analyzes the relationship between urban green space and the health of middle-aged and older adults and its mechanisms.Methods: This study used multiple linear regression, based the data from the China Health and Retirement Longitudinal Study (CHARLS) in 2013, 2015, and 2018, to explore the relationship between urban green space and the health of middle-aged and older adults. At the same time, group regression was conducted to identify the heterogeneity of health effects of urban green space.Results: The research shows that the increase of urban green space areas can significantly improve the health status of middle-aged and older adults. After a series of robustness tests, the results are still valid. In addition, the health effects of urban green space are different because of gender, age, education level, marital status residence, geographical location of the respondents and park quantity distribution. Further research found that reducing hot weather and optimizing air quality are the potential mechanisms of urban green space affecting the health of middle-aged and older adults, providing new evidence for the causal mechanism between urban green space and the health of middle-aged and older adults.Discussion: This study expanded the research scope of the impact of urban green space on the health of middle-aged and older adults, covering a representative sample in China. The results show that urban green space has an important impact on the health of middle-aged and older adults. Policy suggestions are made to help cities optimize the landscape and residents to enjoy ecology.

Land use change affects the supply and demand of water, energy and food and the integration of land elements into the common water-energy-food (WEF) nexus, which is an effective way to strictly adhere to the bottom line of natural resources. First, this study used the entropy method and coupling coordination model to measure the coupling coordination degree of the water-energy-land-food (WELF) nexus in 30 provinces in China during the period of 2006–2019. Then, the regional differences and distribution dynamics were examined with the Dagum Gini coefficient and Kernel density estimation, respectively. Finally, the spatial correlation was analyzed using the global Moran’s I, and a spatial β convergence model was constructed to empirically test its spatial β convergence characteristics. The results show that the coupling coordination degree of the WELF nexus in most of the provinces was at the stage of barely coordinated, with a decreasing trend; the intensity of transvariation was the main source of regional differences in the coupling coordination degree of the WELF nexus, followed by intra-regional differences, while inter-regional differences were small. The national, eastern and central regions had a slight gradient effect, showing regional dispersion characteristics, albeit less obvious; there was a spatial absolute-β convergence and spatial conditional-β convergence nationally and in the three regions. On this basis, policy recommendations were made to realize the synergistic development of land planning, water resources allocation, energy utilization, and food production and to balance regional differences in resources.

Under the urban development trend of sprawl, improving energy use efficiency is a proper way to promote green and low-carbon construction in cities. This paper uses panel data from 283 prefecture-level and above cities in China from 2008 to 2019 to measure the urban sprawl index, and analyze the spatial-temporal evolution law of urban sprawl and electricity consumption. The relationship between urban sprawl and electricity consumption is empirically examined, and the differential effect of urban sprawl on electricity consumption is analyzed. Finally, the impact of urban sprawl on electricity consumption based on a spatial perspective is explored in depth by establishing a spatial error model. We found the following: (1) The levels of urban sprawl and urban electricity consumption are on the rise. The spatial distribution of urban sprawl is more dispersed, and cities with high electricity consumption levels are mostly concentrated in the eastern coastal areas. (2) Urban sprawl exacerbates electricity consumption, and this conclusion is still robust after a series of robustness tests were conducted and endogeneity issues were taken into account. In terms of the influence mechanism, urban sprawl mainly affects electricity consumption by changing the allocation of land resources, increasing the dependence on private transportation, and inhibiting green technology innovation. (3) The incremental effect of urban sprawl on electricity consumption is more pronounced in cities with high sprawl levels, weak environmental regulations, and low green innovation levels, as well as in west cities. (4) Urban sprawl and electricity consumption both have a significant positive spatial correlation. Electricity consumption of cities is not only related to their own regions but also influenced by the adjacent regions, and the spatial correlation is mainly reflected in the random error term. This paper deepens the understanding of the basic laws of urban sprawl affecting urban low-carbon development, which also has implications for new urbanization strategies and green development.

Sustainable development plays a decisive role in achieving the Chinese government's goal of "carbon peaking and carbon neutrality". Taking panel data from 31 provinces in China from 2003-2021, we constructed a fixed-effects econometric model to study the effect of environmental regulation (ER) on environmental equity (EE). The link between ER and EE was explored. The results show that the ER indeed has a beneficial effect on EE and exhibits significant regional and individual characteristics heterogeneity. Particularly, the effect of ER on EE is stronger in Chinese eastern and middle regions and in provinces with lower incomes, higher tax costs, and higher innovation levels. In addition, mechanism analysis reveals that the favorable effect of ER on EE is affected in three ways: government greening services, energy industrial investment, and public environmental attention. Finally, our findings provide an important decision-making reference for advancing the development of ecological civilization and implementing the new development philosophy of a green economy.