Vegetation on the Sunda Shelf, South China Sea, during the Last Glacial Maximum

Abstract

Pollen and phytoliths from sediment cores SO18300, 18302 and 18323 on the continental shelf of the southern South China Sea are analyzed, with special attention to reconstructing vegetation and climate changes on the Sunda Shelf during the Last Glacial Maximum (LGM). The LGM pollen assemblages are characterized by high percentages of pollen from the lowland rain forests and lower montane rainforests, suggesting that the exposed shelf was covered with humid vegetation. A marshy vegetation (with plants of sedges, reeds, bamboo, etc.) developed in the valley along the North Sunda River, and around the marshes were distributed palms and a variety of ferns including tree ferns ( Cyathea). The climate during the LGM inferred from the vegetation was cooler than that at the present day, but no significant decrease in humidity was recorded, at least the change was not sufficient to prevent the growth of rainforest. Finally, the observed fluctuations in percentage of mangrove pollen are considered as a sensitive indicator of coastline migrations on the Sunda Shelf.