Environmental significance of RSL in ancient city wall: historical desertification of Ordos Plateau, Northern China

摘要

Scholars in China have long debated whether the desertification during the past two millennia of the Ordos Plateau was caused primarily by climatic or anthropogenic factors. Focusing on the ancient cities of the Ordos Plateau, and especially on the discovery of Rammed Sand Layer (RSL) in the city wall which proved to be from sand dunes by grain size and scan electron microscope analysis, this study combined the use of historical records and methods of environmental archaeology to clarify the history of the deserts on the Ordos Plateau. The results indicated that some of the ancient cities were built originally in the desert, thus failing to represent a good condition of landscape. Therefore, abandonment of these cities cannot be simply attributed to anthropogenic desertification.