The Climatic Evolution During The Holocene In The Sanyuan Region

Nowdays, the problem of the global environmental degradation, is closely interrelated to human's life. However, the modern environmental variation is the nature environmental estension of the Quaternary Holocene Period, which is related to the environmental of the Holocene. Therefore, the method of studying the rule of the environmental vatiation in Quaternary for forecasting the environment in the future is applicated universally.This issue researched Sanyuan region which is located in the Loess Plateau. The Holocene loess-paleosol sequence of this area realistically records and reflects the evolution of climate and environment in the geological period. On the basis of comprehensive field inspection, the subject made a serious division, lithological description and morphological observation on the Holocene loess stratum in loess plateau of Cuoeyuan of Xianyang. By analyzed magnetic susceptibility, combined with size analysic of the section in Liujiapo village of Xi'an and compared to the sections of other authors, this issue dicussed the loess-paleosol sedimentary sequence, sedimentary sequence, sedimentary law, rate of sedimentation and characteristics of East Asian monsoon evolution in this area, then reconstructed the change sequence of climate and environment during Holocene in Sanyuan, and further revealed the variation rule of climate and environmental during Holocene in the region. Finally, eaplains the climate fluctuation is obvious during the Holocene in this area, and this history can be devided into 5 srages as follows:①10000～8500aBP, it is converersion stage, the climate turned from the last glaciation to the postglacial age. At that time, the temperature becomes higher and higher.②8500～6300aBP, warm phase.③6300～5000aBP, the climate of this phase is cold④5000～3100aBP, the climate of this phase is cold and warm alternate.⑤After 3100aBP, the climate becomes cold. By contrasting the climate with civilizations of human history, we can find the environment evolution with the human cultural development linked closely, the influence.of human activity with the environment is remarkable. For human social harmonious stable and sustainable development environment, the deep research the environmental variation development's tendency on the locate area and global climate is indispensable.