| With the widespread and profound impacts of global change on the natural elements and progress, the society and economy, and even the human activities, the study of global change has become one of the most active frontiers in the current earth science research field. Especially, climatic and environmental changes of Holocene and human history is a very important time scale of the study of global change. However, the geographic surroundings and the natural environment of the southern margin of Tarim Basin, which lies in the hinterland of Eurasia continent, are so special that it is difficult to obtain the proxies indicating its environmental evolution. Hence, there are difficulties in expounding the environmental evolution of southern Xinjiang and the characteristics of human activities comprehensively.Recently, through getting the relatively ideal sedimentary sections, for example the Niya section, the Yuetegan section, the Damugon section, the Tagele section and so on, and by the analyses of different environment proxies (such as geochemical elements, sporo-pollen, magnetic susceptibility, stable carbonate isotope of sediments) and the studying results in the near regions, it has an increasingly important role in studying and reconstructing paleoclimate and paleoenvironment of the southern margin of Tarirn Basin, southern Xinjiang. On the basis of high-resolution sedimentary records of the decadal of the Niya section and multi-indices geological records of the Yuetegan section, a synthetic analysis of the paleoclimatic information is made in this paper. The main results are given as follows:(1), The climate and environment since 4.0 ka had experienced a series of cold-warm and dry-moisture changes. It was obvious that the climate and environment had the tendency of drought after the Maximum optimum period of Holocene. Under this background, climatic and environmental changes of the Southern margin of Tarim Basin during the past 4.0 ka can bedivided into seven stages, ie. 4122 - 3000 aB.P. (2162-1000 BC) --stable and relativewarm-dry, 3000-2500 aB.P. (1000-500 BC)--relative cold-wet and relative warm-dry,2500-2050 aB.P. (500-50 BC) --cold-warm fluctuations, 2050-1450 aB.P. (50BC-550AD) --relative cold-wet, 1450-1150a B.P. (550-850 AD) --relative warm-dry, 1150-700aB.P. (850-1300 AD) --cold-warm fluctuations, 700-0 aB.P. (1300-2000 AD) --relative warm-dry.(2), Since the Maximum optimum period of Holocene (6.5-3.0 kaB.P.) (especially since 4.0 kaB.P. and during the Little Ice Age) . the main discrepancy of climatic and environmental changes of the southern margin of Tarim Basin and the eastern region of China appeared to be thecollocation patterns which were the synchronism in cold or warm conditions and the difference in hydrological conditions. Meanwhile, the discoveries of abrupt climate changes in the past have raised an urgent request for paleoclimatic and paleoenvironmental records. According to a synthetic analysis of climatic proxies of geochemical elements, sporo-pollen, susceptibility and stable carbonate isotope from different sedimental sections in the southern margin ofTarim Basin, Southern Xinjiang, abrupt climate changes mainly occurred at 6.5 kaB.P., 4.0 kaB.P., 3.5 kaB.P., 3.0 kaB.P., 2.5 kaB.P., 2.0 kaB.P., 1.5 kaB.P., 1.0 kaB.P. and 0.75 kaB.P,(3), In order to explore main causes and dynamic mechanism of climatic changes in the southern margin of Tarim Basin, Southern Xinjiang, the red-noise spectra analysis from the proxy records of grain-size, susceptibility and stable carbonate isotope is used to reveal the periodicities of its climatic changes. It is found that climatic and environmental changes of the southern margin of Tarim Basin exhibit the dominant periodicities of 258a, 200a, 125-120a, 100-80a, 70-60a, 55-40a, 35a, 30-25a and 22a. And these periods, which are similar to solar activity periods (such as Haier cycle of 200 years, Gleissberg cycle of 80 years, Century cycle of 100 years, sunspot cycle of 11 years) , discover that climatic and environm...
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