Investigating environmental changes as the driving force of agricultural intensification in the lower reaches of the Yellow River: A case study at the Sanyangzhuang site

In many different societies around the world, people transitioned from slash-and-burn agriculture to an intensive mode of agricultural production. However, why agriculture was increasingly intensified by early farmers remains less understood. This study investigates the driving forces of agricultural intensification from an environmental perspective. Based on our fieldwork at the Sanyangzhuang site and previous paleoclimatic studies, we reconstruct the depositional processes and climatic changes at Sanyangzhuang and its surrounding area between 5000 yr BP and 2000 yr BP. Data suggest that farmers in the lower reaches of the Yellow River were confronted with increasingly severe Yellow River flooding and drier and colder climate during this time period. The environmental changes increase risks of crop failure and famine, disrupt the equilibrium of the social system and induce a process that brings about initial agricultural intensification. This environmental pressure is aggravated by social/political factors and results in the further development of agricultural intensification.