Department of Earth and Environmental Sciences, CEPSAR, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK.
Science. 2011 Feb 25;331(6020):1055-8. doi: 10.1126/science.1197947.
A reconstruction of past environmental change from Ecuador reveals the response of lower montane forest on the Andean flank in western Amazonia to glacial-interglacial global climate change. Radiometric dating of volcanic ash indicates that deposition occurred ~324,000 to 193,000 years ago during parts of Marine Isotope Stages 9, 7, and 6. Fossil pollen and wood preserved within organic sediments suggest that the composition of the forest altered radically in response to glacial-interglacial climate change. The presence of Podocarpus macrofossils ~1000 meters below the lower limit of their modern distribution indicates a relative cooling of at least 5°C during glacials and persistence of wet conditions. Interglacial deposits contain thermophilic palms suggesting warm and wet climates. Hence, global temperature change can radically alter vegetation communities and biodiversity in this region.
从厄瓜多尔重建过去的环境变化揭示了安第斯山脉西侧西亚马逊低山地森林对冰川间冰期全球气候变化的响应。火山灰的放射性测年表明，在海洋同位素阶段 9、7 和 6 的部分时期，约在 32.4 万至 19.3 万年前发生了沉积。保存在有机沉积物中的化石花粉和木材表明，森林的组成因冰期-间冰期气候变化而发生了剧烈变化。在现代分布下限以下约 1000 米处发现的罗汉松化石表明，在冰川期至少有 5°C 的降温，并且保持了湿润的条件。间冰期沉积物中含有喜热棕榈，表明气候温暖湿润。因此，全球温度变化可以彻底改变该地区的植被群落和生物多样性。
