Holocene Climate Change And Paleo-human Living Environment In Qingzhuangzi Area Of Shenyang

The Holocene has become an important geological historical period in human history because of its suitable climatic environment.It gave birth to human civilization and is the cradle of the continuation of human culture.However,behind the seemingly stable climate,there is still a climate cycle of a century to a thousand years.In addition to rapidly changing climate events,studying the relationship between prehistoric human activities and the evolution of the climate and environment has become one of the current focuses.Cultural sites contain numerous information about human activities and changes in the natural environment,and are ideal for studying the characteristics of human civilization.material.Human activities in the Shenyang area are relatively early,and cultural relics and types are quite rich.In recent years,archaeological data have been discovered and published.The cultural layer of the sites near the Hun River and its tributaries is relatively thin,and there are fewer relics and relics in the cultural layer.The difference between raw soil and mature soil is not particularly obvious.At present,there are few researches on human activities and climate environment evolution of cultural sites in the Hunhe River Basin.This paper selects the Qingzhuangzi section located on the first terrace of the river on the south bank of the Hunhe River in Shenyang City,Shenyang City as the research object.Through the high-resolution study of the sediments of the Qingzhuangzi section in Shenyang,the grain size,spores and pollen,geochemical elements,and magnetic susceptibility are used.Test results of other indicators,combined with optical luminescence,AMS¹⁴C dating data,and geomorphological morphology and archaeological data around the site were analyzed and researched to discuss the Holocene climatic environment evolution and ancient human living environment at Qingzhuangzi Site in Shenyang,and the following conclusions were obtained:1.The chronological analysis of the Qingzhuangzi section combined with the archaeological and cultural data shows that the section is mainly deposited between 15.26ka.B.P and 0.24 ka.B.P.The age of the cultural layer at the Qingzhuangzi site is 2.250±0.02ka.It is preliminarily determined that the cultural layer of Qingzhuangzi site is a cultural relic from the Warring States Period to the Western Han Dynasty;2.The results of grain size analysis of Qingzhuangzi profile show that the lithology of Qingzhuangzi profile is dominated by silt,and the silt content gradually decreases from bottom to top;the profile can be divided into two parts,the lower part is aeolian sediment,and the upper part is the Qingzhuangzi cultural layer.,The cultural layer is affected by human activities on the basis of the original sediment,and the sediment particles are relatively coarse;3.The analysis results of geochemical elements show that the Qingzhuangzi section is in a moderate weathering stage;the element oxide ratio shows that the Qingzhuangzi section has experienced a process from humid to arid and then humid;the element mobility results show that the Ca element mobility in the Qingzhuangzi section is the highest,P element has the lowest mobility;4.Pollen data show that the vegetation landscape types of the Qingzhuangzi section mainly experienced savanna landscapes dominated by herbaceous plants,to coniferous forests with more pines—grassland landscapes,to savanna landscapes,and finally to pines.The main cold-temperate coniferous and broad-leaved mixed forest landscape.The overall climate has undergone a process of change from warm and humid to warm and dry,then from warm to dry to cold and dry,and finally to warm and humid;5.The climate in Qingzhuangzi area has experienced three obvious changes from warm and wet to cold and dry at around 12.5ka.B.P,5.5ka.B.P and 2.2ka.B.P;6.Around 2.2ka.B.P,the climate in Qingzhuangzi area experienced a series of changes from warm and humid to warm and cool to cold and dry.Frequent climate changes in the short term and the demographic and social changes caused by them are important factors that led to the decline of the site.