| Some Holocene Loess profiles with several palaeosol layers have been found in Guan Zhong Basin. The layers of loess and palaeosol emerged alternately hi these profiles ,which revealed the environment change. Research has indicated that the climate in Holocene is unsteady. The profile in Jiangyangcun Site, Co.Fufeng of Zhouyuan region is studied in this paper, and it is situated at the east boundary of the archaeological site of the Qiyi city of the predynastic Zhou. Two layers of palaeosol have been contained in the stratum of Holocene in this profile.Field investigation and analysis of grain size, magnetic susceptibility, total Fe, TOC and CaCOs in the profile detailed the characteristics of climatic change during the last 11500 years:(1) 11500-8500a B.P., summer monsoon was stronger and winter monsoon weaker. Temperature went high graduately, at the same time, precipitation got much. During this period, temperature increased from 7癈 to about 11 癈, precipitation increased from under 500mm to 650mm.(2) 8500-6000a B.P., summer monsoon reached its maximum in the Holocene. Precipitation increased remarkably, it reached 750mm. The annual temperature reached about 13.5癈. In this period, Yangshao culture was prosperous.(3) 6000-5000a B.P., This is a period of climatic deterioration. Summer monsoon was weaker and winter monsoon stronger. Precipitation decreased, and eolian dust deposition was accelerated. Yangshao culture declined.(4) 5000-3 lOOa B.P., It got warmer and wetter, pedological process was dominant. Annual temperature and precipitation decreased. Longshan culture developed.(5)<3100a B.P., Climate deteriorated again. Summer monsoon was weaker and winter monsoon stronger. There were much riot in the end of Shang dynasty. Many documents of dust storm and aridity in Shang and Zhou dynasty are found.(6) The prehistoric culture was dominated by natural environment. The change of climate during Holocene in this region has a important impact on the social.
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