2024-04-09 17:43 来源：得道网
在美国，以白人居民为主的城市社区往往比以有色人种为主的社区拥有更多的树木。研究人员4月8日在《npj城市可持续发展》杂志上报告说，一项新的分析表明，这种不平等与高温相关疾病和死亡的差异有关。
大自然保护协会的城市生态学家罗布·麦克唐纳及其同事发现，有色人种为主的社区的树木覆盖率平均比白人社区低11%，夏季气温比白人社区高0.2摄氏度左右。在这些社区，树木每年已经防止了442例额外死亡和大约85,000例医生就诊。在以白人为主的社区，树木挽救了大约200人的生命，并减少了3万多的医生就诊。
Though the results aren’t surprising, the quality of analysis is “really high,” says urban ecologist Steward Pickett of the Carey Institute of Ecosystem Studies in Millbrook, N.Y.
McDonald’s team compared 2020 U.S. census data for 5,723 urban areas across the country with data on tree cover and heat-related mortality and morbidity for those areas. The census data included 180 million people — about half the U.S. population — and the number of people living in majority white and majority nonwhite neighborhoods was a roughly even split.
Trees provide a cooling benefit during extreme heat waves, particularly when shade is cast over concrete or asphalt (SN: 10/24/23). Planting more trees in areas that need it could save hundreds of lives, says McDonald, who is based in basel, Switzerland.
At the most ambitious level, planting 1.2 billion trees across the country could prevent about 460 additional heat-related deaths and about 81,000 additional doctor visits annually, the team projects. But even a five percent increase in preexisting canopy cover could make a substantial difference in cities such as Philadelphia or New York City, McDonald says. Both cities currently have millions of trees. “The places that are most suffering from tree inequality are also the best opportunities for new [trees].”
Pickett has previously shown that plans for green infrastructure often exclude the communities that could benefit most from them (SN: 2/6/23). Inclusivity in planning would help ensure that such communities have a say in the process, he says, and are prepared to maintain both new and old trees.
