Ji John S, Tao Zheng, Miao Hui, Cole-Hunter Tom, Li Xuecao, Rojas-Rueda David, Cai Wenjia
Vanke School of Public Health, Tsinghua University, Beijing, China.
Section of Environmental Health, Department of Public Health, University of Copenhagen, Copenhagen, Denmark.
Lancet Reg Health West Pac. 2025 Jan 16;54:101283. doi: 10.1016/j.lanwpc.2024.101283. eCollection 2025 Jan.
China's growth over recent decades rapidly transformed the urban landscapes. Green spaces provide numerous health benefits including acting as nature-based solutions for climate change risks. Our study aims to track greenness trends in urban areas in China and quantify the health impact of greenness on adult mortality.
In China, we mapped the urban human population distribution aged 20 and above with a 1 km grid (30 arc-second) and used satellite-based remote sensing to measure green space over time to create population-weighted normalized difference vegetation index (NDVI). We tracked changes in greenness in the urban area over time and created a spatial-temporal map. Based on counterfactual scenarios, we calculated averted deaths attributed to NDVI changes from 2000 to 2020.
We analyzed and mapped 390 cities or urban areas in China, covering an urban population of nearly 500 million. We found population-weighted NDVI exhibiting an overall increase from 2000 to 2020 for most cities. Our analysis calculated urban areas that experienced decrease in urban NDVI from 2000 to 2010 could have had an estimated 9951 additional deaths annually (95% CI: 3346-18,106), while increase in NDVI from 2010 to 2020 could have averted an estimated 37,653 deaths annually (95% CI: 26,327-60,135). If the NDVI were increased to the target level in 2000 and 2010, the number of deaths would be reduced by 110,976 (95% CI: 82,010-171,561) and 118,330 (95% CI: 87,362-183,283), respectively.
Greenness has increased in most urban in China since 2000. Considering the ongoing impacts of climate change and urbanization, sustained efforts in greenness management could serve as an effective resilience factor for protecting population health.
Natural Science Foundation of Beijing (IS23105), National Natural Science Foundation of China (82250610230, 72061137004), World Health Organization (2024/1463606-0), Research Fund Vanke School of Public HealthTsinghua University (2024JC002).
近几十年来，中国的发展迅速改变了城市面貌。绿地带来诸多健康益处，包括作为应对气候变化风险的基于自然的解决方案。我们的研究旨在追踪中国城市地区的绿化趋势，并量化绿化对成年人死亡率的健康影响。
在中国，我们以1公里网格（30弧秒）绘制了20岁及以上城市人口分布，并利用卫星遥感随时间测量绿地，以创建人口加权归一化植被指数（NDVI）。我们追踪了城市地区绿化随时间的变化，并创建了时空地图。基于反事实情景，我们计算了2000年至2020年因NDVI变化而避免的死亡人数。
我们分析并绘制了中国390个城市或城市区域的地图，覆盖城市人口近5亿。我们发现，大多数城市的人口加权NDVI从2000年到2020年总体呈上升趋势。我们的分析计算得出，2000年至2010年城市NDVI下降的城市区域每年可能额外有9951人死亡（95%置信区间：3346 - 18106），而2010年至2020年NDVI上升每年可能避免约37653人死亡（95%置信区间：26327 - 60135）。如果2000年和2010年NDVI提高到目标水平，死亡人数将分别减少110976人（95%置信区间：82010 - 171561）和118330人（95%置信区间：87362 - 183283）。
自2000年以来，中国大多数城市的绿化有所增加。考虑到气候变化和城市化的持续影响，在绿化管理方面持续努力可作为保护人口健康的有效恢复力因素。
北京市自然科学基金（IS23105）、中国国家自然科学基金（82250610230、72061137004）、世界卫生组织（2024/1463606 - 0）、清华大学万科公共卫生与健康学院研究基金（2024JC002）。
