The Last Glacial Maximum: stability and change in a western Amazonian cloud forest
نویسندگان
چکیده
The climatic and vegetation history of a western Amazonian cloud forest is documented in a continuous pollen record spanning the full last glacial period between 43.5 and 22k cal. yr BP. The chronology for this record is based on eight radiocarbon dates yielding a low-resolution pollen analysis for the region. A bioclimatic envelope model was generated on the basis of modern altitudinal distributions and the pollen data, which produced a glacial palaeotemperature estimate of ca. 5 C relative to present. Palaeoecological evidence of continuous moist cloud forest cover in the basin indicates that western Amazonian forests were not fragmented during the LGM. This evidence supports wet conditions in western Amazonia at the LGM and further refutes hypotheses of Amazonian aridity during the last ca. 44k cal. yr BP. Copyright 2005 John Wiley & Sons, Ltd.
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