中国4Ma来孢粉植物群气候的多重旋回模型  

MULTICYCLIC MODEL OF PALYNOFLORA CLIMATE SINCE 4MA IN CHINA

作　　者：童国榜[1] 郑宏瑞[1] 杨振京[1] 曹家栋 孔昭宸[1] 严富华[1] 罗宝信[1] 

机构地区：[1]中国科学院植物研究所,国家地震局地质研究所,地质矿产部天津地质矿产研究所

出　　处：《海洋地质与第四纪地质》1995年第4期81-96,共16页Marine Geology & Quaternary Geology

基　　金：中科院西安黄土与第四纪地质研究室的资助。

摘　　要：本文应用频谱分析方法，研究了近４Ｍａ来的孢粉植物群气候波动，确定存在准１２０，３０（或４０），１０（或６）万年的周期。依据孢粉植物群的时空分布建立了多重气候旋回模型，该模型将４Ｍａ来气候划分为３个１．２Ｍａ的气候幕，１２个０．３（或０．４）Ｍａ的气候期，４８个０．１（或０．０６）Ｍａ的气候段。并且讨论了模型与自然环境演变及季风气候兴衰的关系。指出在冬、夏季风交替活动过程中，夏季风兴盛于２．０－１．８Ｍａ及０．８－０．２Ｍａ两个时期；冬季风活跃于２．５－２．３Ｍａ及１．２－０．８Ｍａ两个时期。Recently, practice declared that rich evidences of palaeoclimate and palaeoenvi-ronment changes are preserved in continental deposits,Our problem now is to seek cor-rect and effective methods to find these evidences and then understand their contents.We have studied 15 pollen time series in China's main large sedimentary basins,anddone frequency spectrum analysis on the basis of filtering analysis. As a result,we havediscovered quasi-periodity of 1.2,0. 4(or 0. 3) and 0.1(or 0.06)Ma B.P. in the pollentime series, and also found that the quasi-periodity before 1.4Ma B.P. was differentfrom that after 1.4Ma B.P. and the value became larger.This conclusion confirms thecorrectness of Milankovitch's astroclimatologic theory from developn1ent of polynoflo-ra;on the other hand,it proves that climate change is not only restrained by the parame-ters of the Earth orbit movement,but also affected by crustal movement,that's to say,climate change has fluctuations of different time scales. Therefore,we advance the climatic multicyclic model according to time-space distri-bution of palynoflora and relevant environment changes in China,In the model,climatesince 4Ma B.P. is divided into 4 climatic episodes of1.2 Ma(Fig.5),12climatic periodsof 0.4(or 0.3)Ma and 48 climatic subperiods of 0.1(or 0.06)Ma.The climatic multicyclic model proves that climate is a complicated system,affectedand controlled by many different dynamic factors.The climatic fluctuation is helicalmovement,which has 3 chief characteristics:a. multiple,b.overlapping and C. nonplastic.The development of palynoflora reflects evolution of palaeomonsoon in China.Thriving of broad-leaved forest reflected that the effect of sumrner monsoon wasstrengthened.Enlarging of steppe marked that the effect of winter monsoon was in-creased.Through comprehensive study of different palaeoenvironment data ,it is indicat-ed that development of palaeomonsoon since 4 Ma B,P,went through four stages in Chi-na :climatic episode Ⅳ(4-2.6MaB. P.),palaeomonsoon stage;climatic episode Ⅲ(2.

关 键 词：多重气候旋回 气候模型 孢粉植物群气候 晚新生代 

分 类 号：Q914.66[天文地球—古生物学与地层学]