Vegetation evolution and millennial-scale climatic fluctuations since Last Glacial Maximum in pollen record from northern South China Sea

In order to study vegetation evolution and environmental change since the Last Glacial Maximum (LGM), a total of 180 pollen samples with an average time resolution of 150 years were analyzed on the top parts (0-31 m, 0-27 kaBP) of deep sea sediments from ODP Site 1144 (20 degrees 3.18'N, 1170 degrees 25.14'E), northeastern SCS. The characteristic features of pollen diagram include that pine dominates in the interglacial, and herb pollen dominates with a good deal of tropical-subtropical pollen in the last glacial, and from 18 kaBP the tropical-subtropical pollen influx rose abruptly, while the herbaceous pollen influx and percentage dropped quickly, indicating that climate turned warmer and more humid, and more tropical-subtropical vegetation grew on the mainland and the emerging continental shelf, while the grassland on the shelf diminished. A detailed comparison shows an earlier change of pollen assemblages at the glacial-interglacial transition between MIS6 and 5 (Termination 11) than the ice volume change indicated by the oxygen isotope record, implying that mid-low latitude climate warming preceded ice sheet retreat. Millennial-scale climatic fluctuations of vegetation change in pollen record are also discussed.