Iterative variation of human staples related to climate–society interactions in the North China plain between the 7th and 19th centuries

Staple crops play a pivotal role in human societies. Considerable attention has been dedicated to the changes in staple crops, particularly the alternation between wheat and foxtail millet in ancient China. However, the long-term development of staple crops in historical China is still unclear. Archaeobotanical investigations at the Zhengding Kaiyuan Temple South (ZKS) excavation site, which deposited continuously from the Tang Dynasty to the Qing Dynasty (618–1911 CE), have provided crucial clues. The result indicates to a recurring change in staple crops. During the Northern Song Dynasty and Yuan Dynasty, wheat dominated, while during the Tang Dynasty, Five Dynasties, Ming Dynasty and Qing Dynasty, foxtail millet was the most important staple crop. From the combination of written and paleo-climatic records, it can be inferred that the development of watermill technology and hydraulic engineering promoted wheat cultivation during the Tang Dynasty to Yuan Dynasty. While the deterioration of climate led to a resurgence of foxtail millet during the Ming Dynasty and Qing Dynasty. This study examines the changes in staple crops and their influencing factors in the North China Plain from the 7th to the 19th centuries, emphasizing the importance of technological innovations and climate changes in shaping human societies.