Smithsonian Tropical Research Institute, Box 0843-03092, Balboa, Ancon, Republic of Panama.
Science. 2010 Nov 12;330(6006):957-61. doi: 10.1126/science.1193833.
Temperatures in tropical regions are estimated to have increased by 3° to 5°C, compared with Late Paleocene values, during the Paleocene-Eocene Thermal Maximum (PETM, 56.3 million years ago) event. We investigated the tropical forest response to this rapid warming by evaluating the palynological record of three stratigraphic sections in eastern Colombia and western Venezuela. We observed a rapid and distinct increase in plant diversity and origination rates, with a set of new taxa, mostly angiosperms, added to the existing stock of low-diversity Paleocene flora. There is no evidence for enhanced aridity in the northern Neotropics. The tropical rainforest was able to persist under elevated temperatures and high levels of atmospheric carbon dioxide, in contrast to speculations that tropical ecosystems were severely compromised by heat stress.
热带地区的温度据估计比上新世的值增加了 3°到 5°C，在古新世-始新世极热事件（PETM，5630 万年前）期间。我们通过评估哥伦比亚东部和委内瑞拉西部三个地层剖面的孢粉记录来研究热带森林对这种快速变暖的反应。我们观察到植物多样性和起源率的快速而明显的增加，出现了一组新的分类群，主要是被子植物，增加了低多样性古新世植物群的现有存量。在北新热带地区没有证据表明干旱加剧。热带雨林能够在高温和高浓度二氧化碳的条件下持续存在，与热带生态系统因热应激而严重受损的推测形成对比。
