甘肃小陇山林区全新世中期以来古植被演替的研究

RESEARCH OF VEGETATIONAL SUCCESSION ON THE XIAOLONGSHAN MT.SINCE MIDDLE HOLOCENE

采用花粉孢子分析和１４Ｃ测定年代的方法，来研究小陇山林区植被的历史演替。根据小陇山林区不同地点３个剖面的孢粉资料和１４Ｃ数据，首次推断该区自全新世中期以来，古植被和古气候经历了３个演替阶段：距今７５００－５０００年，为以栎类为主的落叶阔叶林和局部为针阔混交林，气候温暖湿润；距今５０００－２５００年，为以栎类为主的针阔混交林，气候温和略干；２５００年至今，早期为栎林和针阔混交林，晚期是以栎类占优势的针阔混交林，和早期相比，气候转凉变干。最后指出了该地区两种典型的植被类型。

ased on the characteristics of sporepollen assemblages from three section of Xiaolongshan Mountain.and radiocarbon dating.The present paper deals with the changes of the vegetation and climate.During 7500-2500 a.B.P.,the vegetation types is dominated by decidous broadleaved forest and coniferous broadleaved mixed forest,which mainly consist of Quercus (Big type),Quercus (little),Betula,Pinus and Artermisia.It is warm and humid.Period from 2500-5000 a,B.P.,it become little warm and dry,with the vegetation of broadleaved forest and coniferous broadleaved mixed forest,which mainly species are Quercus (Big),Pinus and Artermisia.After 5000 a.B.P.,the forest is dominated by Quercus (little),Quercus (Big),Pinus and Artermisia.Late period the vegetation mainly consist of Quercus (Big),Pinus and Artermisia.The climate resemble recent.As a whole,the vegetational succession of Xiaolongshan MT,divided into three stages,two vegetation types.Osk forest have been a dominant position.