东海陆缘地区晚第四纪沉积的孢粉及其古环境意义

通过对东海陆缘地区东海1井、高桥G2孔、人民广场孔等晚第四纪地层的孢粉研究，划分出了6个孢粉组合带，并恢复了本地区植被演替、气候波动的6个阶段：第1阶段为稀疏的针叶、落叶阔叶混交林，反映气候冷干(晚更新世晚期)；第2阶段为针叶、阔叶混交林-草原，反映气候温凉略湿(前北方期)；第3阶段为舍常绿阔叶树的针叶、阔叶混交林，反映气候温和略干(北方期)；第4阶段为以栲属、青冈栎为主的常绿阔叶林，反映气候暖热潮湿(大西洋期)；第5阶段是以栎、松、蒿为主的针叶、阔叶混交林，反映气候温和略干(亚北方期)；第6阶段是以落叶栎类、常绿栎类、松为主的落叶阔叶、常绿阔叶、针叶混交林-草原，反映气候温暖湿润(亚大西洋期)。这种气候波动与世界性气候变化相一致，为本地区的地层年代划分和对比提供了可靠的证据，为晚第四纪古植被、古气候、古环境的重建提供了重要的孢粉学资料。

PALYNOLOGICAL ASSEMBLAGES OF LATE QUATERNARY IN THE CONTINENTAL MARGIN OF THE EAST CHINA SEA AND ITS PALEOENVIRONMENT SIGNIFICANCE

Six palynological assemblages were distinguished through an intensive study on pollen and spores from cores DH1,G2 and RM at the continental margin of the East China Sea.Six stages about the evolution of vegetation and climate were reconstructed for the late Quaternary in this area as follows: mixed sparse forest of conifers and deciduous broad-leaf trees,reflecting a cold and dry climate (late Pleistocene); mixed forest of conifers and broad-leaf trees-grassland,reflecting a temperate and moist climate(sub-arctic period); mixed forest of conifers and broad-leaf trees with a few evergreen broad-leaf trees,reflecting a temperate and slightly dry climate(Boreal period); evergreen broad-leaf forest being mainly composed of Quercus(evergreen) and castanopsis indicating a hot and wet climate(Atlantic period); mixed forest of conifers and broad-leaf trees,indicated by Quercus,Pinus and Artemisia as main element in palynological assemblages,reflecting a warm and dry climate (Sub-Boreal period); mixed forest of deciduous broad-leafes,evergreen broad leaves and conifers,with Quercus (deciduous,evergreen) and pines as the main components,reflecting a warm and moist climate (Sub-Atlantic period).These fluctuations coincide with the global climatic changes.The present study provides reliable evidence for biostratigraphy and reconstructions of paleovegetaton,paleoclimate and paleoenvironment in this area since the late Quaternary.