摘要
对采自渤海湾西北岸曹妃甸深槽部位的 96 - 2 4钻孔柱样进行了详细的孢粉分析 ,建立了综合孢粉图式及古气候曲线 ,认为曹妃甸地区自晚更新世末期以来古植被与古气候经历了以下阶段的演变 :晚更新世末期 (2 5～ 11ka B.P.)气候寒冷干燥 ,植被为主要由蒿、藜组成的干草原 ;早全新世 (11～ 7.5 ka B.P.)气候温凉略干 ,发育针阔混交林—滨岸草原 ;中全新世 (7.5～ 3ka B.P.)气候温暖湿润 ,发育以阔叶树为主的针阔混交林—滨岸草原 ;晚全新世 (3ka B.P.至今 )气候温凉偏干 ,发育针阔混交林—滨岸草原。值得指出的是 ,在中全新世中期 (5 ka B.P.左右 )出现了一次明显的冷期 ,即“新冰期”,气候变得寒冷潮湿 ,发育以针叶树为主的针阔混交林—滨岸草原植被 ,这一短暂的冷期在钻孔中反映的十分明显。
In this paper,the generalized sporopollen scheme and the palaeoclimate curves of the studied region are constructed based upon the comprehensive analyses of sporopollen from hole 96 24,which is located in a deep trough of the Caofeidian area in the Bohai Bay.According to the climate variation,the evolution sequences since the last stage of the late Pleistocene in the Caofeidian area are as follows. During 25 ka～11 kaB.P. i.e.the last period of the late Pleistocene,the main vegetation was dry prairie,which was composed of Artemisia and Chenopodiceae and resulted from the cold and dry climate.During 11 ka～7 5 kaB.P. i.e.the early period of Holocene,the deciduous broad leaved and coniferous mixed forests and the forest steppe in a mild and a little humid climate replaced the dry prairie gradually.During 7 5 ka～3 kaB.P. i.e.the middle period of Holocene,the climate was warm and humid.The vegetation was the deciduous broad leaved and coniferous mixed forest with the broad leaved forest as dominator and the forest steppe.During the period from 3 kaB.P. to present i.e.the late stage of Holocene,climate was mild,cool and a little dry.The vegetation was the deciduous broad leaved and coniferous mixed forest with Pinus and Quercus as dominant species and the forest steppe. It is well worth emphasizing that a short cold time called “New Ice Age”appeared in the middle of the middle period of Holocene around 5 kaB.P.In this period,climate turned into cold and humid and the vegetation turned into the deciduous broad leaved and coniferous mixed forests with the coniferous forest as dominator and the forest steppe.This short cold time is reflected very obviously by the analyses of sporopollen.
出处
《海洋地质与第四纪地质》
CAS
CSCD
北大核心
2000年第2期87-92,共6页
Marine Geology & Quaternary Geology
关键词
古值被
古气候
晚更新世末期
曹妃甸
渤海湾
late Pleistocene
palaeovegetation
palaeoclimate
evolution sequences
Caofeidian
