摘要
对西藏那曲孔玛盆地第四系湖相沉积地层中的孢粉进行了分析,该套湖相沉积物记录了早更新世晚期((108.7±11.0)×103 a)-中更新世(【(13.8±1.4)×103 a)时期该地区的植被与环境演化过程.1.087~0.778Ma时期,气候温凉而干旱,呈现出暗针叶林植被景观;0.778~0.531Ma时期,气候总体偏暖,属山地暖温带暗针叶林气候环境,气候存在2次由温暖湿润-寒冷干旱的变化过程;0.531~0.262Ma时期,气候稳定,呈针阔叶混交林植被景观,气候以温暖湿润为主;0.198Ma~更晚(小于0.13Ma)时期,云杉属逐渐取代单/双束松属,成为最主要成分,铁杉含量明显增加,气候总体向寒冷方向发展,气候存在寒冷干旱-寒冷湿润-干旱偏暖的变化过程,属山地寒温带暗针叶林特征,气候总体持续变冷.
Based on the sporopollen analysis of the Quaternary lacustrine strata in Kongma basin in Naqu,Tibet,this paper presents the vegetation and environmental evolution of the basin between the late stage((108.7±11.0)×103 a)of early Pleistocene and mid-Pleistocene(<(13.8±1.4)×103 a).This area was a dark coniferous forest vegetation landscape and the climate was warm,cool and dry from 1.087Ma to 0.778Ma.In the time span about 0.778-0.531Ma,the climate was generally warm and had a hilly warm temperate dark coniferous forest vegetation landscape and underwent two transitions from wet-warm to drycold.Between 0.531Ma and 0.262Ma,the climate was stable and characterized by being warm and wet,presenting a vegetation landscape of mixed coniferous and broad leaved forest in the Kongma area.During the period about 0.198to <0.13 Ma,Piceapollis gradually replaced Abietineaepollenites/Pinuspollenites and became the major component with a significant increase of Tsugaepollenites.On the whole,the climate evolved to cold and had a cold-dry to cold-wet to dry-warm change.It can be seen as a hilly cold temperate dark coniferous forest and had a continuing cold trend.
出处
《地球科学(中国地质大学学报)》
EI
CAS
CSCD
北大核心
2013年第S1期1-9,共9页
Earth Science-Journal of China University of Geosciences
基金
国土资源大调查项目(Nos.12120113006100
1212010610108
1212011087114)
关键词
青藏高原
孔玛盆地
孢粉分析
沉积物
古环境
Tibetan plateau
Kongma basin
sporopollen analysis
sediments
palaeoenvironment