干旱区生态环境知识资源中心

Previous studies on the Rice-Millet (foxtail millet and common millet) Blended Zone in Chinese Neolithic have not clearly addressed such questions as the importance of primitive rice-millet mixed agriculture to human lifestyle and livestock managements within this region, the relationship among the development of the agriculture, paleoenvironment, and cultural interactions, and so on. Here stable carbon and nitrogen isotope analysis of human and pig bones from the Qinglongquan site was conducted, covering two cultural phases, namely the Qujialing Culture (3000 BC to 2600 BC) and the Shijiahe Culture (2600 BC to 2200 BC). Based on this analysis, we further discussed the diets of ancient humans and pigs in the site, investigated the importance of rice-millet mixed agriculture to human and pig diets, and explored the relationship among the primitive rice agriculture and millet agriculture, cultural interactions, and paleoenvironment. The delta (13)C values of human bone collagen (-16.7aEuro degrees to -12.4aEuro degrees, averaging -14.6aEuro degrees +/- 1.3aEuro degrees, n=24) revealed that both C(3) and C(4) foods were consumed, probably from the contribution of rice (C(3) plant) and millets (C(4) plants) due to the coexistence of these crops at this site. In addition, the human mean delta (13)C value suggested that millet agriculture was only minor in human diets. The human delta (15)N values (6.6aEuro degrees to 10.8aEuro degrees, averaging 9.0aEuro degrees +/- 1.2aEuro degrees, n=24) showed that animal resources played a significant role in human diets, and varied greatly. The mean delta (13)C value of the pigs (-14.3aEuro degrees +/- 2.5aEuro degrees, n=13) was quite similar to that of the humans, but the mean delta (15)N value of the pigs was slightly less (1.3aEuro degrees). The similar delta (13)C and delta (15)N values between humans and pigs suggested that the pigs consumed a lot of humans’ food remains. No correlations of the delta (13)C and delta (15)N values between humans and pigs showed that both human and pig diets were based mainly on plant foods, which might be related to highly developed rice-millet mixed agriculture at that time. In comparison with the human and pig diets between the two periods, millet agriculture contributed more than 10% in the Shijiahe Culture, if a simple mixing model was used. This apparent dietary shift matched the climatic variation and agricultural development through the time. In warm and humid climate with the expansion of the Qujialing Culture northwards, rice was widely cultivated. However, when the climate was cold and arid, northern culture was expanding southwards. Thus, millet agriculture became more important.