上海东部地区晚第四纪沉积的孢粉组合及古环境

通过对上海东部地区南汇鹤鸣孔、东海1井、高桥G2孔3口钻井晚第四纪地层的孢粉研究,划分出了6个孢粉组合带和3个亚带,恢复了本地区植被演替、气候波动的6个阶段:第1阶段晚更新世晚期,反映气候凉冷稍湿;第2阶段前北方期,反映气候温凉略湿;第3阶段北方期,反映气候温和略干;第4阶段大西洋期,反映气候热暖潮湿;第5阶段亚北方期,反映气候温暖略干; 第6阶段亚大西洋期,反映气候温暖湿润。这为本地区晚第四纪古植被、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 Eastern Part of Shanghai and Its Paleoenvironment

Through intensive study on pollen and spores from the cores of Hm,Dh1 and G2 at the eastern part of Shanghai,six palynological assemblages and three sub-assemblages were distinguished.There are six stages of the evolution of vegetation and climate,which were reconstructed for the Late Quaternary on this area as follows: mixed sparse forest of conifers and deciduous broad-leave trees,reflecting the cold and a little wet climate(late stage of Late Pleistocene);forest of deciduous broad-leave trees with Pinus,Taxodiaceae-grassland,reflecting a temperate and little wet climate(sub-arctic period);mixed forest of conifers and broad-leave trees with a few evergreen broad-leave trees,reflecting a temperate and slightly dry climate(Boreal period);evergreen broad-leave forest being mainly composed of Quercus(evergreen) and Castanopsis,indicating a hot and moist climate(Atlantic period);mixed forest of conifers and broad-leave trees,indicated by Quercus,Pinus and Gramineae as main element in palynological assemblages,reflecting a warm and little dry climate(Sub-Boreal period);mixed forest of deciduous broad-leaves,evergreen broad-leaves and conifers,Quercus(deciduous,evergreen) and pines,being the main components,reflecting a warm and wet climate(Sub-Atlantic period). These fluctuations coincide with the global climatic changes.The study provides reliable evidence for the division and comparison of the age of the sediment at this region,also for the biostratigraphy and reconstructions of paleovegetaton,paleoclimate and paleoenvironment in this area since the Late Quaternary.