江苏省江都市大桥镇ZKA4钻孔第四纪孢粉组合及其环境变化研究

本文依据江苏省江都市大桥镇第四系钻孔(ZKA4)中孢粉的分布,自下至上划分了11个孢粉组合:1.Betula-Ulmus-Artemisia,2.Ulmus-Chenopodiaceae-Quercus,3.Artemisia-Gramineae-Quercus,4.Liquidambar-Polypodiaceae-Ulmus,5.Pinus-Quercus-Betula-Juglans,6.Quercus-Juglans-Artemisia,7.Quercus-Polygonum-JuglansCarya,8.Betula-Gramineae-Artemisia,9.Quercus-Polypodiaceae,10.Podocarpus-Triorites-Polypodiaceae,11.Pinus-Podocarpus-Juglans-Pterocarya。依据孢粉组合,识别出更新世以来七个气候冷暖变化阶段。孢粉组合1为常绿落叶针阔叶混交林,气候以冷干为主,向上气候回暖;孢粉组合2为高寒灌丛—落叶针阔叶混交林,以冷干为主;孢粉组合3为草本—落叶针阔叶混交林,较前一阶段气候变暖,偏暖干;孢粉组合4-5以落叶阔叶为主,整体上以变暖为主;孢粉组合6-7为落叶针阔叶混交林,整体气候为暖湿,早期略干;孢粉组合8-9为以针叶为主的针阔叶混交林,气候温凉偏湿;孢粉组合10-11为常绿—落叶阔叶混交林,气候以湿暖为主。

PALYNOLOGICAL ASSEMBLAGES FROM THE BOREHOLE ZKA4AT DAQIAO TOWN,JIANGDU CITY,JIANGSU PROVINCE AND THEIR ENVIRONMENTAL MEANINGS

Based on the data of palynology from the borehole ZKA4at Daqiao town,Jiangdu,Jiangsu Province,11assemblages are recognized as follows:1.Betula-Ulmus-Artemisia,2.Ulmus-Chenopodiaceae-Quercus,3.ArtemisiaGramineae-Quercus,4.Liquidambar-Polypodiaceae-Ulmus,5.Pinus-Quercus-Betula-Juglans,6.Quercus-JuglansArtemisia,7.Quercus-Polygonum-Juglans-Carya,8.Betula-Gramineae-Artemisia,9.Quercus-Polypodiaceae,10.Podocarpus-Triorites-Polypodiaceae,and 11.Pinus-Podocarpus-Juglans-Pterocarya.Based on palynological assemblage(PA),seven stages of climate change have been identified:Stage 1(corresponding to PA 1)was characterized by evergreen and deciduous broad-leaved mixed forests,representing a cold and dry,with subsequent warmer climate;Stage 2(corresponding to PA 2)was dominated by alpine shrubs,deciduous broad-leaved mixed forests,representing a cold and dry climate;Stage 3(corresponding to PA 3)was dominated by herb deciduous broad-leaved mixed forests,show the beginning of a warm and dry climate;Stage 4(corresponding to PA 4-5)was associated with deciduous broad-leaved forests,displaying the overall warmer climate;Stage 5(corresponding to PA 6-7)was dominated by deciduous broad-leaved mixed forests,indicating it was warm and slightly dry;Stage 6(corresponding to PA 8-9)was dominated by the coniferous forests(consisting mainly of coniferous and broad-leaved mixed forests),representing a cool and wet climate;Stage 7(corresponding to PA 10-11)was associated with evergreen and deciduous broadleaved mixed forests,mainly representing a warm and wet climate.