Evidence for crop structure from phytoliths at the Dongzhao site on the Central Plains of China from Xinzhai to Erligang periods

Abstract The Dongzhao site is located in Zhengzhou on the Central Plains of China and has been dated to between the late Longshan culture (between 4500 BP and 4000 BP) and the Zhou dynasty (between 3046 BP and 2256 BP). Phytolithanalyses were performed on 36, 43, and 14 sediment samples collected from this site, which have been dated to the Xinzhai (between 3870 BP and 3720 BP), Erlitou (between 3735 BP and 3530 BP), and Erligang (between 3600 BP and 3300 BP) periods, respectively, in order to develop a better understanding of agricultural practices and cropping structures during the Xia and Shang dynasties. The results of this study suggest that agricultural practices in use at Dongzhao comprised a mixed farmingsystem in which broomcorn millet, foxtailmillet, rice, and wheat were grown. Data show that broomcorn millet was the dominant crop during the Xinzhai and Erligang periods, while the foxtailmillet was a secondary crop, and that both rice and wheat were minor components of this system. The proportions of rice decreased while those of wheat increased over time through these periods, and high ubiquities of scutiform-bulliform phytolithsfrom reeds were commonly observed, suggesting that these plants were widely utilized, and probably managed during both the Xinzhai and Erligang periods. The findings reported in this study confirm the fact that phytolithanalyses can complement and strengthen interpretations drawn on the basis of other botanical remains within an archaeological context. Analysisof phytoliths, in tandem with interpretation of carbonized plant remains from the Dongzhao site, affords a range of new insights concerning the development of agricultural structures on the Central Plains of China during the Xia and Shang dynasties, and provides new evidence highlighting the probable relationship between agricultural structures and the origin and early development of Chinese civilization.