Publication Date:
2019
Description:
〈div data-abstract-type="normal"〉〈p〉The patterns and drivers of late Quaternary vegetation dynamics in the southeastern United States are poorly understood due to low site density, problematic chronologies, and a paucity of independent paleoclimate proxy records. We present a well-dated (15 accelerator mass spectrometry 〈span〉14〈/span〉C dates) 30,000-yr record from White Pond, South Carolina that consists of high-resolution analyses of fossil pollen, macroscopic charcoal, and 〈span〉Sporormiella〈/span〉 spores, and an independent paleotemperature reconstruction based on branched glycerol dialkyl tetraethers. Between 30,000 and 20,000 cal yr BP, open 〈span〉Pinus-Picea〈/span〉 forest grew under cold and dry conditions; elevated 〈span〉Quercus〈/span〉 before 26,000 cal yr BP, however, suggest warmer conditions in the Southeast before the last glacial maximum, possibly corresponding to regionally warmer conditions associated with Heinrich event H2. Warming between 19,700 and 10,400 cal yr BP was accompanied by a transition from conifer-dominated to mesic hardwood forest. 〈span〉Sporormiella〈/span〉 spores were not detected and charcoal was low during the late glacial period, suggesting megaherbivore grazers and fire were not locally important agents of vegetation change. 〈span〉Pinus〈/span〉 returned to dominance during the Holocene, with step-like increases in 〈span〉Pinus〈/span〉 at 10,400 and 6400 cal yr BP, while charcoal abundance increased tenfold, likely due to increased biomass burning associated with warmer conditions. Low-intensity surface fires increased after 1200 cal yr BP, possibly related to the establishment of the Mississippian culture in the Southeast.〈/p〉〈/div〉
Print ISSN:
0033-5894
Electronic ISSN:
1096-0287
Topics:
Geography
,
Geosciences
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