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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   
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末次冰期以来塔里木盆地沙漠、黄土的沉积环境与演化   总被引:10,自引:0,他引:10  
本文论述了诱发塔里木盆地沙漠及南缘亚砂土和黄土的搬运、沉积,至少在末冰冰期初,即已由现代本区盛行的NE和NW风系所奠定,在此风系作用下沉积的沙漠、亚砂土和黄土未有显著变化。其间,盆地虽多经流水作用,但并未能够改变沙漠及其以南的亚砂土、黄土存在的基本格局。风成相和流水相地层中的古气候证据揭示,末次冰期以来本区沙漠与黄土沉积主要是在连续干旱的气候环境下进行的。  相似文献   
3.
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   
4.
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   
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.
全新世中国季风区西北缘沙漠演化初步研究   总被引:36,自引:0,他引:36  
本文在对区内几个全新世剖面研究的基础上,证明毛乌素沙漠和共和盆地沙区在最近一万年以来曾有过程度不同的6次固定成壤阶段,腾格里沙漠仅在最佳期被固定成壤。时间上风成砂与砂质古土壤波动交替、承袭穿时,空间上东侵西撤是我国季风区西北边缘沙漠演化的特有模式。  相似文献   
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THE FORMATION, EVOLUTION AND CAUSE OF THE Mu Us DESERT IN CHINA   总被引:6,自引:0,他引:6  
Comprehensive correlation and analysis on the stratigraphic structure of the Quaternaryeolian sand in the Mu Us Desert comfirm that the Desert has been in existenceintermittently since the initial stage of the Quaternary at latest. The Desert is asteppe type sandy desert characterized by mosaic distribution of shifting, semi-shifting, semi-fixed and fixed dune and areas of loess grass land. It did not evolve toward uniform shift-ing sand, but underwent a series of normal and reverse development processes from the occur-rence of shifting sand to the spread, fixation and reduction of the sandy desert to grassland.Climatic fluctuation since the Quaternary is the primary factor for the formation and evolutionof the Desert, while neotectonics and human activities are the secondary factors.  相似文献   
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