Utilizing network optimization to mitigate rising greenspace exposure inequalities in Chinese cities from 2000 to...

Urban greenspaces enhance human well-being and promote sustainable development in rapidly urbanizing regions by delivering vital ecosystem services, including cooling, air purification, and recreation. In China, where cities accommodate a large share of the population amid persistent environmental pressures, disparities in greenspace exposure pose a major obstacle to equitable access; these disparities arise from geographic, climatic, socioeconomic, and landscape factors. Although awareness of such inequalities is growing, their long-term trajectories, demographic and city-scale patterns, and viable spatial optimization approaches remain largely unexplored. Here we show that greenspace exposure inequality across 246 Chinese cities increased by 25 % from 2000 to 2020 and is projected to rise further by 12.2-15.7 % by 2050 under middle-of-the-road and fossil-fueled development scenarios, disproportionately affecting older, less-educated women and megacity residents. Geodetector and random forest analyses reveal that this rise results from interactions among greenspace coverage, population density, and patch connectivity, which explain 83.9 % of the inequality. A network-based optimization approach that improves patch connectivity-without expanding total greenspace-can reduce disparities by 10.3-20.8 %, with greater efficacy in high-inequality cities and among vulnerable populations. Our results highlight how precise landscape interventions can advance social equity in greenspace access, supporting Sustainable Development Goal 11 for inclusive, resilient urban environments.