Millet manuring as a driving force for the Late Neolithic agricultural expansion of north China

Xin Wang,Songmei Hu,Pengcheng Zhang,Benjamin T Fuller,Yaowu Hu,Xue Shang

doi:10.1038/s41598-018-23315-4

Abstract

Research in to the nature of Neolithic agriculture in China is often focused on topics such as the domestication and spread of cereal crops and the reconstruction of human and animal diets in the past. Field management practices, such as organic manuring, have not been systematically investigated in Chinese archaeology. Here we present an isotopic dataset for archaeological foxtail millet (Setaria italica) and common millet (Panicum miliaceum) grains as well as associated faunal remains (both domesticated and wild) from seven sites in the Baishui Valley of north China, in order to find direct evidence of organic manuring during the Late Neolithic period. The elevated nitrogen isotope values of the millet grains (5500-3500 cal BP) in comparison with the estimated local vegetation indicates that millets were organically manured by animal dung, mostly likely originating from domestic pigs. Considering the low nitrogen contents of loess soils and their unsuitability for intensive cultivation, this organic manuring by animal dung would have played a key role in maintaining soil productivity and crop yield, which was necessary to support the demands of agriculture and cultural expansion during the Late Neolithic on the Loess Plateau of China.

Highlights

Long-term farming practices where crops are annually cultivated in the same location can result in the depletion of soil nutrients and a loss of crop yields and quality[1]
During 2010–2012, excavations in the region by a team from the Shaanxi Provincial Institute of Archaeology, and abundant archaeobotanical and faunal remains were recovered at seven archeological sites, and these provided a good collection for studying the crop management and animal husbandry practices in northern China from the late-Yangshao to Longshan cultural periods (Fig. 1)
The δ15N values of crops can be variable as a result of different human management practices such as irrigation, manuring, crop rotation, etc.[38]

Summary

Introduction

Long-term farming practices where crops are annually cultivated in the same location can result in the depletion of soil nutrients and a loss of crop yields and quality[1]. While the farming practices of the Yangshao culture have been studied in the past[29,30,31], only limited research has focused on the isotopic analysis of millets from Chinese archaeological sites[32,33,34]. We report radiocarbon dates (n = 10) and carbon (δ13C) and nitrogen (δ15N) stable isotope ratio results for charred foxtail (n = 29) and common (n = 20) millet grains from seven Yangshao archaeological sites (Xiahe, Mapo, Nanshantou, Beishantou, Xishan, Hanzhai, Muwanghe) in the Baishui Valley of Shaanxi Province. During 2010–2012, excavations in the region by a team from the Shaanxi Provincial Institute of Archaeology, and abundant archaeobotanical and faunal remains were recovered at seven archeological sites, and these provided a good collection for studying the crop management and animal husbandry practices in northern China from the late-Yangshao to Longshan cultural periods (Fig. 1). Additional artifacts included: pottery, stone artifacts, and plant and animal remains (Fig. 1E,F)

Methods

Results

Conclusion