Contrasting inequality of green spaces and buildings between cities in China

The significance of sustainable urban development is unequivocally emphasized within the framework of the United Nations Sustainable Development Goals (SDGs), with urban green spaces playing a pivotal role. However, there exists uncertainty concerning the rationalization of urban land use structures in China. This study used a new indicator, the ratio of construction land area to green space area (UGI), designed to investigate both the static and dynamic change of green space from 2000 to 2020. The analysis revealed that urban construction land expanded by a factor of 1.85 between 2000 and 2020, while China's overall UGI saw a substantial decline of 77.8%. Furthermore, the text identified three different patterns of change in ΔUG (the changes in construction area to green space), with Datong city having a value of 1,580, where the urban development was seriously unbalanced. Notably, results indicated the proportion of secondary industry and the GDP had a significant correlation with UGI and the inequality is more significant within the province of Sichuan and Hunan. In conclusion, the findings emphasize the imperative for cities with high UGI values to increase their financial investments in green spaces, thereby expediting progress towards the realization of the SDGs.