黄河源区距今13万年来古气候演化

综合分析黄河源区-青海玛多地区斗格涌盆地钻孔剖面的孢粉及易溶盐等气候代用指标,揭示了该区130ka B P以来的古气候演变规律。即:130.0-110.0ka B P寒冷干旱;110.0-82.0ka B P寒温较湿;82.0-10.4ka B P寒冷干旱;10.4ka B P至现代(即全新世)温湿冷干交替。全新世古气候又可划分为3期:早全新世升温期(10.4-7.5ka B P)(Anathermal);中全新世大暖期(7.5-3.5ka B P)(Megathermal);晚全新世降温期(3.5ka B P至今)(Katathermal)。本区古气候总的规律是:冷期长且比全球其它地方提前,暖期短且开始时期滞后。全新世以来气候波动具有千年尺度的振荡规律,晚全新世至今,气温有逐渐降低,湿度逐渐变干的趋势。 

THE PALAEOCLIMATIC EVOLUTION OF THE YELLOW RIVER SOURCE AREA SINCE 130ka B P

By a comprehensive analysis of the proxy indices of climate such as readily soluble salt and spore-pollen of borehole profiles in Dougeyong Basin,the palaeoclimatic evolution pattern of the Yellow River source area since 130 ka B P has been revealad:1.From 130 ka B P to 110 ka B P,it was cold and dry;2.From 110 to 82 ka B P,cold but more humid;3.From 82 to 10.4ka B P,cold and dry;4.From 10.4 ka B P to recent(i.e.,Holocene),there was an alternation of warm-humid and cold-dry climate.And the climate in Holocene can further be divided into three stages:1)10.4-7.6 ka B P it was Anathermal;2)7.5-3.5 ka B P Megathermal;3)3.5 ka B P present Katathermal.In general palaeoclimate the area has a longer and earlier cold period and a shorter and later warm period as compared to other regions of the world.The climate fluctuations since Holocene have occurred at a time scale of one thousand years.Since Late Holocene there has been a gradual decreasein temperature and humidity.