Carbon And Nitrogen Stable Isotopes Analysis Of Human And Animal Bones From Xidiannan Site,Yangqu

At present,there are hints to show that the ancestors around 4000 a BP in Xinding Basin and around Spring and Autumn period and warring States period in Taiyuan Basin in Shanxi area were mainly engaged in millet agriculture.However,there is still a lack of relevant evidence to prove the economic features of production in the specific time range of Taiyuan Basin,which can not be used to reveal the evolution process of the production economy of the prehistoric people in this area.Therefore,in order to understand the specific situation of the development of subsistence in Shanxi during the period of Longshan Culture and the role it played in the progress of civilization,the Xidiannan site located in Taiyuan Basin during the Period of Longshan Culture is selected as a case study.In order to reveal the economic situation of the Longshan Culture Period in Taiyuan Basin,the article takes 3 human bones and 34 animal bones（3 deer bones,3dog bones,5 cattle bones,6 sheep bones and 17 pig bones）unearthed from the Xidiannan site of Yangqu as the research object,and uses the method of AMS-¹⁴C dating and stable isotope analysis of carbon and nitrogen to discuss the age of the site,the food structure of animals and humans,and the feeding method of the livestock,then,restore the economic situation of the human.AMS-¹⁴C dating results show that the carbon-14 age of the owner of M1 is4200±30 a BP,and the age range after tree-ring correction is 4844 a BP～4620 a BP,which is generally range from the late Yangshao Culture Period to Miaodigou phaseⅡCulture Period.Preliminary identification results of the tomb showed that the owner of M1 tomb was a child aged 5 to 6,and no information of burial goods was unearthed.However,the remains and their assemblages of this site displayed typical Longshan culture feature.Finally,the Xidiannan,Youyao and Xinghuacun sites show similar cultural characteristics,so the Xidiannan site should be a Longshan cultural site.Still,the ¹⁴C dating results of M1 human bones show that the burial date is earlier.Considering that the site has a large area and many cultural layers,its time span should be long.The ¹⁴C dating results of M1 human bone cannot reflect the age of the whole site.Therefore,the date of the Xidiannan site should be in the period of Longshan culture.Carbon and nitrogen stable isotope analysis results show that deer(δ¹³C:-20.8‰～-18.7‰,mean value:-19.6‰±1.1‰;δ¹⁵N:2.9‰～3.6‰,mean value:3.3‰±0.4‰,n=3)mainly lived on C₃foods,indicating that the local wild vegetation was mainly C₃plants.Different from deer,theδ¹³C values of sheep andδ¹⁵N values(δ¹³C:-17.2‰～-14.3‰,mean value:-16.2‰±1.0‰;δ¹⁵N:6.7‰～9.6‰,mean value:8.1‰±1.2‰,n=6)are significantly higher than that of deer.There are some differences within them,which can be divided into 3 groups:A and B.Group A（YQ17 and YQ19）has higherδ¹³C values（-16.4‰and-16.3‰,respectively）andδ¹⁵N values（9.3‰and 9.6‰,respectively）.They were younger,consumed more milk,lived in water-deficient environment or were fed with high-protein fodders.In group B（YQ15,YQ16,YQ18,YQ20）,theδ¹³C values are low（-16.3‰,-16.8‰,-14.3‰and-17.2‰,respectively）,but theδ¹⁵N values are high（6.7‰,8.3‰,7.4‰and7.2‰,respectively）.Sheep are likely to be unable to obtain sufficient food resources by themselves during winter and spring.In this case,artificial fodders（such as millet straw）may be used as a supplement to their diets.Obviously,although sheep are mainly raised in the wild,their diet still influenced by millet farming.Most cattle(δ¹³C:-20.2‰～-14.6%,mean value:-16.4‰±2.6‰;δ¹⁵N:3.5‰～6.8‰,mean value:5.3‰±1.6‰,n=4)ate C₃plants,but a small amount of C₄food was added to their diet.Domestic pigs(δ¹³C:-7.5‰～-6.3‰,mean value:-6.9‰±0.3‰;δ¹⁵N:6.1‰～8.4‰,mean value:7.5‰±0.6‰,n=17)and dogs(δ¹³C:-7.3‰～-6.8‰,mean value:-7.0‰±0.3‰;δ¹⁵N:6.6‰～7.9‰,mean value:7.1‰±0.7‰,n=3)and cattle YQ13(δ¹³C:-10.7‰;δ¹⁵N:8.7‰)mainly fed on C₄food.Pigs and dogs mainly lived on millet and its by-products and ate food leftovers and/or leftovers and even the feces of the humans.Cattle YQ13 may fed specially with a large amount of millet and by-products by human.Human(δ¹³C:-8.6‰～-7.1‰,mean value:-7.7‰±0.8‰;δ¹⁵N:9.5‰～10.3‰,mean value:10.0‰±0.4‰,n=3)mainly lived on C₄food,that is,millet and domestic pigs and/or dogs fed with millet and its by-products.Therefore,the subsistence economy of humans in the Taiyuan Basin,where the Xidiannan site located,was mainly millet agriculture and domestic pig feeding industry,as well as stocking and feeding of foreign cattle and sheep.One-way ANOVA analysis of C and N stable isotope data of human and animal bones from this site and some other contiguous and contemporaneous sites（such as Xinzhai site in the Central Plains hinterland,Taosi site and Qingliangsi cemetery in the Linfen Basin,Xinzhang site in the Xinding Basin and Shengedaliang site in the Northern Shaanxi area）showed that the subsistence economy in Taiyuan Basin,where the Xidiannan site located,was a little monotonous and the social complexity was limited.In addition,the late terrain conditions were not suitable for human survival,which may be an important reason for the single subsistence economy and slow local civilization.