Study On The Holocene Environmental Change In The Eastern Region Of Guanzhong Basin And Its Influence On Human Culture

The Holocene climate period is a fast developmental stage of Human culture. In resent years ,many researchers have investigated and found the close relationship between the environmental change of the Holocene and human cultural development. Laoguantai cultural relics is an early one since the New Stone Age. The author selects the Holocene environmental change in the eastern Guanzhong Basin and its influence on human culture as the topic of the thesis.Laoguantai profile lies in the Laoguantai village, Hua county, Shaanxi province; it also lies on the second step-land of the southern bank of Wei River. 3m thick profile of the Holocene loess exposes near a brick kiln. It can be observed that the sediments of the Holocene loess is continuous and thus it reflects the environmental change and human activities since the Holocene. Meanwhile, Laoguantai profile is a perfect one because it lies in the periphery of the Laoguantai cultural relics. On the basis of outdoor observation and indoor experimental analysis, the author selects proxy substitute indexes, such as grain-size, magnetic susceptibility, microelements, CaCOs and pH value, etc. Moreover, the thesis also calculates and investigates the remains of human activities kept in the profile. Through the comparison study of these climatic substitute indexes, the thesis reveals the process of the evolution of climatic environment and human culture in the eastern area of Guanzhong Basin. Finally, the thesis investigates the relationship between the evolution of environment and that of human culture.The thesis draws the following conclusion:(1) 11500-8500aB.P., through comprehensive analysis of these proxy climatic substitute indexes reveals: this was a period in which the temperature risen and the precipitation increased, but it was mainly still dry and cold; the vegetation was prairie or forest prairie; there were flood deposits in the dust sediments of late stage; and it was the shifting period from the New Stone Age to the Old Stone Age.(2) 8500-6000aB.P, according comprehensive analysis of these proxy climatic substitute indexes shows: this was a period in which the temperature was the highest and the precipitation was the greatest; there appeared forest vegetation; in the middle stage of the period was Laoguantai culture; and after that there appeared Yangshao early culture.(3) 6000-5000aB.P, through comprehensive analysis of these proxy climatic substitute indexes indicates: this was a dry and cold period in which the temperature was the lowest and the precipitation was the least; the vegetation may mainly be forest prairie; in the early stage of the period appeared Yangshao middle culture-the prosperous culture of Miaodigou type, and in the late stage there was Yangshao late culture-the culture of Xiwang village type.(4) 5000-3100aB.R, through comprehensive analysis of these proxy climatic substitute indexes indicates: this was another warmth and humidity period in which the temperature risen and the precipitation decreased, but the warmth and humidity were not as proper as those in the best period mentioned above; the forest vegetation may recovered; there were flood sediments in the dust in the early-middle stage of the period; in the early stage was Longshan culture, and in the early-middle stage the human culture developed and it entered into period of Xiashang civilization.(5) Since 3100 aB.R, through comprehensive analysis of these proxy climatic substitute indexes indicates: this was a dry and cold period in which the temperature fell the precipitation decreased; the vegetation may be forest prairie; human civilization further developed and the human' s influence on the environment was greater in intensity and wider in range.