Wood Tana E, Tucker Colin, Alonso-Rodríguez Aura M, Loza M Isabel, Grullón-Penkova Iana F, Cavaleri Molly A, O'Connell Christine S, Reed Sasha C
USDA Forest Service International Institute of Tropical Forestry, Río Piedras, PR, USA.
US Geological Survey, Southwest Biological Science Center, Moab, UT, USA.
Nat Commun. 2025 Sep 16;16(1):8222. doi: 10.1038/s41467-025-62065-6.
Tropical forests are a dominant regulator of the global carbon cycle, exchanging more carbon dioxide with the atmosphere than any other terrestrial biome. Climate models predict unprecedented climatic warming in tropical regions in the coming decades; however, in situ field warming studies are severely lacking in tropical forests. Here we present results from an in situ warming experiment in Puerto Rico, where soil respiration responses to 4 C warming were assessed half-hourly for a year. Soil respiration rates were 42-204% higher in warmed relative to ambient plots, representing some of the highest soil respiration rates reported for any terrestrial ecosystem. While respiration rates were significantly higher in the warmed plots, the temperature sensitivity (Q) was 71.7% lower, pointing to a mechanistic shift. Even with reduced Q, if observed soil respiration rates persist in a warmer world, the feedback to future climate could be considerably greater than previously predicted or observed.
热带森林是全球碳循环的主要调节者，与大气交换的二氧化碳比任何其他陆地生物群落都多。气候模型预测，未来几十年热带地区将出现前所未有的气候变暖；然而，热带森林中严重缺乏实地变暖研究。在此，我们展示了在波多黎各进行的实地变暖实验的结果，在那里，对土壤呼吸对4摄氏度升温的反应进行了为期一年的半小时一次的评估。与环境温度地块相比，升温地块的土壤呼吸速率高出42%-204%，这是任何陆地生态系统所报告的一些最高土壤呼吸速率。虽然升温地块的呼吸速率显著更高，但温度敏感性（Q）降低了71.7%，这表明存在机制转变。即使Q降低，如果在更温暖的世界中观察到的土壤呼吸速率持续存在，对未来气候的反馈可能会比之前预测或观察到的要大得多。
