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1.
中国全新世大暖期的气候波动与重要事件   总被引:175,自引:0,他引:175  
根据70年代以来中国全新世孢粉及其他古植物、古动物、古土壤、古湖泊、冰芯、考古、海岸带变化等多方面研究资料,推断中国全新世大暖期(Megathermal)出现于8。5—3ka BP,延续达5.5ka,其间有多次剧烈的气候波动与寒冷事件。8.5—7.2ka BP为不稳定的暖、冷波动阶段,伴随着降水增加和植被带的北迁西移。新石器文化的迅速发展。7.2—6ka BP为稳定的暖湿阶段,即大暖期的鼎盛阶段(Megathemal Maximum)。夏季风降水及新疆与蒙古,北方降水显著增加,植被空前繁茂,为仰韶文化的盛期。6—5ka BP是气候波动剧烈,环境较差的阶段,出现强降温事件,影响文化发展。5ka BP后,气候和环境较前改善,文化遗址数量猛增。4.0ka BP左右,气候一度恶化,出现大洪水灾害,此后直到3ka BP左右气候仍相当暖湿。  相似文献
2.
中国全新世大暖期鼎盛阶段的气候与环境   总被引:57,自引:0,他引:57  
本文根据孢粉、古土壤、古湖泊、冰芯、考古、海面等变化,重建了全新世大暖期鼎盛阶段(7.2—6.0kaBP)的气候与环境。恢复了大暖期盛期的植被带、气温、降水以及海面变化等。认为其时华南温度比今高1℃,长江流域高2℃,华北、东北以及西北可能高3℃,青藏高原南部达4—5℃,冬季升温幅度更大于年平均温度。百年级的增暖相伴夏季风的扩张和冬季寒潮的衰退,植被带北迁西移,内蒙、新疆、青海和西藏普遍出现高湖面指示着降水量有较大幅度的增长。中国东部则在6.5—5.0kaBP间出现全新世中的最高海面,约高于现今1—3m,导致沿海地区约7×10~4km~2被海水所淹,达到全新世最大海侵范围。  相似文献
3.
内蒙古岱海湖泊环境变化与东南季风强弱的关系   总被引:38,自引:0,他引:38  
岱海位于东南季风区的西北缘,属气候波动的敏感段,最近100ka湖泊连续沉积剖面的分析表明,季风迁移存在不同时间尺度波动的准周期,根据湖泊沉积环境的特点,岱海地区始终表现出干冷和暖湿气候型的交替,说明东南季风的强弱和进退在气候变化中扮演了主导的角色。  相似文献
4.
最近130ka中国的古季风——Ⅱ.古季风变迁   总被引:27,自引:0,他引:27  
根据海陆相互作用对古季风变迁的影响和代用气候指标的时间序列,初步重建了最近130ka和18ka东亚季风变迁的历史,重点阐述了夏季风环流活动的基本特征,提出了中国中、东部季风气候旋回及有关环境过程模式,初步探讨了我国古季风变迁的机制。  相似文献
5.
最近130ka中国的古季风——Ⅰ.古季风记录   总被引:24,自引:0,他引:24  
现今中国季风气候的特点可以作为辨认古季风气候记录的线索。文中着重阐述最近130ka东南季风区的各种古季风记录,它们主要是:历史记录,包括黄土-古土壤序列、沙漠、湖泊、雪线和林线、大陆架沙漠化现象等的地质记录,由植被和哺乳动物代表的生物记录。其中,黄土高原的黄土-古土壤序列反映了过去亚洲冬季风和夏季风的环境效应突出气候期相互交替的历史。亚洲古季风变迁是中国古气候和古环境变迁的一个重要控制因素。  相似文献
6.
The Climatic Fluctuation and Important Events of Holocene Megathermal in China   总被引:12,自引:0,他引:12  
Data from various sources including the ice core, inland lakes , paleosols in loess and eolian sands, sea level fluctuations, paleozoological, archeological evidences especially palynology and bontanical studies of China are reviewed . Holocene Megathermal mainly appeared during 8. 5-3 ka BP and lasted for 5. 5 ka. There were several strong climatic fluctuations and cooling events during this period, e. g. it was an unstable temperature fluctuation phase during 8. 5-7. 2 ka BP and was accompanied with the increase of the precipitation as well as the northward and westward migration of the vegetation zone ; the rapid development of Neolithic Culture happened in this phase. It was a stable warm and wet phase from 7. 2 to 6 ka BP, i. e. Megathermal Maximum, when monsoon was rainfall almost throughout China, plants were unprecedentedly flourished, and the Yangshao Culture reached its climax. It is characterized by strong climatic fluctuation and adverse environment during 6-5 ka BP and the impact of strong  相似文献
7.
The characteristics of the modern monsoon climate o?China may be used as clues for recognizing the records of paleomonsoon climate. The present paper deals primarily with the various paleomonsoon records of the last 130,000 years in the southeast monsoon area. These records mainly come from the following three fields: (i) the historical, (ii) the geological, including loess-paleosol sequence, deserts, lakes, snowlines, timberlines, the phenomena of continental desertization and so on, and (iii) the biological, presented by vegetation and mammals. Among these records, the loess-paleosol sequence in the Loess Plateau reflects a climatic history characterized by alternation of two different climatic periods when the Asian winter monsoon and summer monsoon showed pronounced effects on environment, respectively.  相似文献
8.
Based upon the effect of land-sea interaction on the paleomonsoon variation and the time series of climatic proxy-indicators, the historical Asian monsoon variation over the last 130,000 and 18,000 years has been reconstructed with an emphasis on the basic characteristics of summer monsoon circulation. The monsoon-climatic cycles and associated model of environmental development over the central and eastern China are proposed and the mechanism of paleomonsoon variation of China preliminarily discussed. The variation of East Asian monsoon circulation should be regarded as a regional result of both solar-radiation changes and the global glacial-interglacial cycles. The episodic uplifting of the Qinghai-Xizang Plateau since the late Miocene has to a large extent controlled the forming and evolution of the paleomonsoon circulation of China.  相似文献
9.
Daihai Lake, located in NW margin of SE monsoon region, belongs to the sensitive area for climatic fluctuation. The analysis of continuous sedimentary column with an age of 100 ka indicates that there exists the different quasiperiodicity in time scales for monsoon shift. The climatic fluctuation in the Daihai Basin shows all along the alternation of cold and dry with a warm and wet climatic pattern, suggesting that the strength and drift of SE monsoon play a controllable role in the climatic change.  相似文献
10.
Based on data from palynology, paleosols, paleolimnology, ice core, archeology, sea levels, etc. , we reconstructed climates and environments of the Holocene Megathermal maximum (7. 2-6. 0 ka B. P. ), particularly vegetation zones, temperatures, precipitation and sea-level fluctuations. Annual mean temperature during that period was estimated at 1 ℃ higher than today for South China, 2 ℃ higher for the Changjiang River Valley, about 3℃ higher for North China, Northeast China and Northwest China and up to 4 - 5 ℃ higher for southern Qinghai-Xizang Plateau. Relative winter temperatures increased much more than average annual temperatures. The centennial-scale warming was accompanied by the expansion of summer monsoon and recession of winter cold currents as well as northward and westward shift of vegetation zones. Higher lake levels registered in all inland lakes of Inner Mongolia, Xinjiang, Qinghai and Xizang indicated that precipitation increased to a certain extent. The Holocene highest sea level i  相似文献
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