我国东北全新世花粉分布图及其分析

根据６５个地点化石花粉分析资料，编制了我国东北全新世每隔每千年时间片断的花粉百分值图和花粉等时线图，并进行初步分析，花粉图展示了东北地区植被演化的主要特征。桦树在全新世初期遍布从三江平原到辽东半岛南端的东北东部地区，在森林中占据色对优势地位，榆属和栎属等阔叶乔枯木要在早全新世的大部分时间内是东部森林中的主要种类；在大约５ｋａＢＰ以后，松属在东北现在的森林地区开始增加，云，冷杉属也表现出较明显扩大，

MAPPING AND ANALYZING ON THE HOLOCENE POLLEN DATA OF NORTHEAST CHINA

Based on a pollen data set from 65 sites, a preliminary attempt is made to produ ce the isopolls and isochrones for eight pollen taxa and seven time slices of No rtheast China. These pollen maps show significant vegetation changes during the past 10 000 years in the current forest regions of Northeast China, with the ear ly Holocene characterized by the widely distributed Birch , the mid Holocene by the development of temperate deciduous forest mainly consisting of Quercus and Ulmus, and the late Holocene by the marked increase in Pinus abun dance and the development of temperate mixed conifer and deciduous forest. Also found from the pollen mapping is the mid late Holocene forest decline with an o bvious south to north propagation nature.