Journal of Geographical Sciences ›› 2008, Vol. 18 ›› Issue (3): 328-340.doi: 10.1007/s11442-008-0328-6

• Climate and Environmental Change • Previous Articles     Next Articles

Rise and decline of ancient salt industry revealed by Na and Ca concentrations in sediments at Zhongba site, Chongqing

ZHU Cheng1, JIANG Fengqing2, MA Chunmei1, XU Weifeng1, HUANG Linyan1, ZHENG Chaogui3, LI Lan1, SUN Zhibin4   

  1. 1. School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing 210093, China|
    2. Xinjiang Institute of Ecology and Geography, CAS, Urumqi 830011, China|
    3. Department of Geography, College of Chuzhou, Chuzhou 239012, Anhui, China|
    4. Sichuan Provincial Institute of Archeology, Chengdu 610041, China
  • Received:2008-03-25 Revised:2008-06-15 Online:2008-09-25 Published:2008-09-25
  • Supported by:

    The Key Project of National Natural Science Foundation of China, No.90411015; University Doctoral Foundation of China, Grand No.20050284011; The Prior study project for Key Basic Scientific Issue of Nanjing University, Grand No. 0209005206; Open Foundation of the State Key Laboratory of Loess and Quaternary Geology from the Institute of Earth Environment, CAS, No.SKLLQG0503; Foundation of Modern Analyses Center of Nanjing University, No.0209001309

Abstract:

Based on dynastic period division and AMS14C dating performed on the sedimen-tary layers at Zhongba and Yuxi sites, and also the analysis of Na, Ca and Mg of 201 sedi-mentary samples from Zhongba site and that of Ca and Na in 47 sedimentary samples from Yuxi by using an inductively coupled plasma–mass spectrometry (ICP), we found that there were 35 time periods when the contents of Ca and Na were reversely correlated, i.e. when-ever the content of Ca was the highest, the content of Na was the lowest, and vice versa. Among them, there were 21 time periods when the content of Ca was the highest, and Na was the lowest, indicating that there were about 21 prosperous periods of ancient salt pro-duction at Zhongba site since 3000BC. Other 14 time periods with the peak values of Na while the low values of Ca indicate 14 declined periods of salt production at Zhongba site since 3000BC. The conclusion obtained from the reverse relationship between Ca and Na contents in this paper is consistent with that “the salt production at Zhongba site started in the new stone age, developed in the Xia and Shang dynasties, reached at the heyday in periods from the Western Zhou to the Han Dynasties, maintained stable to develop in the Tang and the Song dynasties, and gradually declined after the Song Dynasty because the sea salt were conveyed into Sichuan region, however, still had production in the 1970s–1980s”, educed from archeological exploration. All the above mentioned results indicate that there is a re-verse relationship obviously between the contents of Na and Ca in sediments at Zhongba site for ancient salt production, which can

Key words: Zhongba site, Zhongxian County, reverse relationship between contents of Na and Ca, rise and de-cline of early salt production