Changing of crop species and agricultural practices from the Late Neolithic to the Bronze Age in the Zhengluo region, China

An assemblage of charred plant remains from 17 sites in the Zhengluo region has been collected and analyzed with a semi-quantitative method representative index and also with a multivariate statistical method correspondence analysis for this article. It provides a useful perspective for the understanding of the changing in the crop spectrum and crop husbandry practices from ca. 2500 BC to 1046 BC in this region. In the Longshan period, rice was subdominant while more dry-resistant broomcorn millet was cultivated during the Xinzhai and Erlitou periods; however, the importance of rice rose again in the Erlitou period, especially stood out in some central settlements and wheat witnessed a remarkable increase in the Shang period. Combined with the ecological information from arable weeds, it might conclude that agricultural techniques played a much more important role in farming since the Bronze Age. It is possible that in the Bronze Age, elaborate irrigation system, fertilizer practice, and spikelet-form storage method guaranteed the stable production and the preservation of crops, especially rice in some of the central settlements.