Data from: Urban warming reduces aboveground carbon storage

A substantial amount of global carbon is stored in mature trees. However, no experiments to date test how warming affects mature tree carbon storage. Using a unique, citywide, factorial experiment, we investigated how warming and insect herbivory affected physiological function and carbon sequestration (carbon stored per year) of mature trees. Urban warming increased herbivorous arthropod abundance on trees, but these herbivores had negligible effects on tree carbon sequestration. Instead, urban warming was associated with an estimated 12% loss of carbon sequestration, in part because photosynthesis was reduced at hotter sites. Ecosystem service assessments that do not consider urban conditions may overestimate urban tree carbon storage. Because urban and global warming are becoming more intense, our results suggest that urban trees will sequester even less carbon in the future.

成熟林木储存着全球规模可观的碳储量。然而迄今为止，尚无实验探究气候变暖对成熟林木碳储量的影响。本研究依托一项独特的全市域析因实验，探究了增温与昆虫植食作用对成熟林木生理功能及碳固存（carbon sequestration）速率（即每年储存的碳量）的影响。城市增温提升了树木上植食性节肢动物的种群丰度，但此类植食生物对林木碳固存的影响微乎其微。与之相反，城市增温与预估12%的碳固存损失相关，部分原因在于高温生境下树木的光合作用受到抑制。未考虑城市环境条件的生态系统服务评估，可能会高估城市林木的碳储量。鉴于城市增温与全球变暖的强度均在加剧，本研究结果表明，未来城市林木的碳固存能力将进一步下降。