Rising social complexity, agricultural intensification, and the earliest rice paddies on the Loess Plateau of northern China

Geoarchaeological studies of landscapes immediately adjacent to archaeological sites can contribute information on the direct impact of small-scale societies on their associated landscapes. This direct connection allows us to understand aspects of the motivations, economic decision-making and agricultural strategies and how they affected local site catchments. The origin and spreading of farming communities onto the Loess Plateau of northern China provides a good example of this. We recorded sediment profiles that were immediately adjacent to the site of Huizui in the Yiluo River Basin. Here we identified evidence for human land-use beginning with the early Mid-Holocene deposits which are consistent with stable hillslope soils, indicating that the first mixed forager-millet farmers of the Peiligang Neolithic had a very light ecological footprint on the landscape. This is in contrast to the later middle Neolithic Yangshao Period farmers. Sediments from the Yangshao Period revealed paleolandscape and phytolith evidence for the earliest Neolithic paddy farming well outside of the natural habitat of wild rice. In addition to evidence for massive deforestation and soil erosion, a 15 m deep sediment sequence containing sets of gravels (beginning ca. 7200 cal BP) and gleyed soils dating from ca. 6600 cal BP, contained rice phytoliths, archaeological waste suggesting manuring, and micromorphological data indicating trampling. These signs of intensive landscape management go hand-in-hand with rapidly increasing social complexity.