Carbon And Nitrogen Stable Isotope Analysis Of Plant Remains From Qingqiu Mound Site In Heze

Analysis of carbon and nitrogen isotope composition of plants can give clues on environmental conditions.In addition,the growth of crops are controlled by humans,so its stable isotope composition can be used as a reference of agricultural management.Crop δ15N values can act as a proxy for the application of animal manure,and crop δ13C values reflect the water status.In this study,δ13C and δ15N values of crop remains from the Qingqiu mound site in Heze were analyzed to study early agricultural practices.In order to characterise the possible changes of δ13C value and δ15N value associated with charring,we desigened charring experiments of morden foxtail and common millets.The average δ13C andδ15N offset of charred foxtail millets are 0.6‰ and 0.5‰,for common millet are 0‰and 0.7‰.Stable isotope analysis of charred plant remains from Qingqiu site suggest increased labour input(more intensive)from Longshan period to Han dynasty in this site.We found that local residents put higher labour into rice and soybean which have small-scale than millet.During Longshan culture period,people were already using animal manure.Theδ15N value of plant remains reflected the increasing of manure application over time in this site.The manure application for wheat were higher in Shang Dynasty,lower in Zhou Dynasty and higher again in Han Dynasty.This process may reflect the change of the status of wheat in crops.This study demonstrated the early agricultural management and strategy of Qingqiu mound site in Heze.The significant high δ15N values of crop should be considered in diet reconstruction.Stable isotopes analysis of archaeological plant remains has considerable contributions to understanding the relationship between humans and plants in an archaeological context.