南海深海柱状沉积物中孢粉和藻类研究及古环境意义

SPOROPOLLEN AND ALGAE RESEARCH ON DEEP-SEA SEDIMENTS IN THE SOUTH CHINA SEA AND ITS PALEOENVIRONMENT SIGNIFICANCE

对南海东南部323站深海柱状剖面高分辨率孢粉和藻类进行了研究,将323站从下至上划分为4个孢粉组合带,依次为:1带:Polypodiaceae Pinus Quercus(常绿) Dacrydium Gramineae;2带:Dicranopteris Quercus(常绿) Pinus Polypodiaceae Cyathea;3带:Polypodiaceae Pinus Cyperaceae Quercus(常绿) Lycopodium;4带:Dicra nopteris Pteridinium Pinus Cyathea Polypodiaceae。并相应恢复了南海75000a以来4个植被、气候演替阶段,依次为:暖热而稍干的热带北缘半常绿季雨林—炎热、湿润的热带季雨林—暖热而稍干的热带北缘半常绿季雨林—炎热、湿润的热带季雨林,结合氧同位素测年资料,对323站地层时代划分作了讨论,为南海古气候、古环境演变研究提供了科学的依据。

Based on the highresolution sporopollen and algae research of the sediments at Core 323 in the southeastern South China Sea, four sporopollen zones have been distinguished in ascending order:Zone 1:PolypodiaceaePinusQuercus(evergreen)DacrydiumGramineae Zone 2:DicranopterisQuercus(evergreen)PinusPolypodiaceaeCyatheaZone 3:PolypodiaceaePinusCyperaceaeQuercus(evergreen)Lycopodium Zone 4:DicranopterisPteridiniumPinusCyatheaPolypodiaceaeThe sporopollen zones reflect four stages of vegetation and climatic fluctuatios of the South China Sea since 75 000 years ago. The four stages were as follows:warm and a little dry semievergreen monsoon rain forest of northern tropic,hot and wet tropical monsoon rain forest,warm and a little dry semievergreen monsoon rain forest of northern tropic,hot and wet tropical monsoon rain forest. Combined with oxygen isotope dating, the sporopollen and algae data can be one of the evidences for stratigraphic division and for reconstruction of paleoclimate and paleoenvironment in the South China Sea.