长江三角洲地区晚第四纪古土壤中的植物硅酸体及其古环境意义

PHYTOLITH AND ITS PALEOENVIRONMENTALSIGNIFICANCE IN THE STUDIES OF LATE QUATERNARY PALEOSOLS IN THE YANGTZE DELTA AREA

长江三角洲地区晚第四纪古土壤层，即以前所谓的“暗绿色硬粘上层”过去被看作是“哑地层”，本文首次发现该层中含有丰富的植物硅酸体，且各种类型的硅酸体在地层中均有出现，并在剖面上有较大的变化。在定量统计分析的基础上，利用其组合特征，并进一步利用对应分析方法，探讨了本区晚第四纪古地理、古环境变迁历史，认为该层形成子一种弱草甸环境，且在其形成过程中有四次气候冷—暖变化。

Late Quaternary paleosol in the Yangtze Delta area,which used to be called "Dark Green Stiff Clay Layer",were considered as“barren bed”.For the firs time,abundantphytolith of various types has been found ,with changes obviously from bottom to top.Based on the quantitative statistical data and assemblages of phytolith,and through cor-respondence analysis,the authors conc1uded that the paleosol layers were formed in theenvironment of weak meadow,during which there were fourcold-warm paleoclimatic cy-cles.