Popis: |
Based on the records of the bottom elevations of 482 ancient water wells collected from published archaeological reports, we reconstructed the paleo-underground water levels (PUWL) in the urban areas of Chengdu, Changsha, Nanjing, Suzhou, Suqian, and Yancheng cities in the vicinity of 30° N in China. The PUWL fluctuations varied between the inland and the coastal regions and their transitional areas. There were four PUWL phases in the inland areas: low in Han (206 B.C.–A.D. 220), high in Tang (A.D. 618–907), low in Song (A.D. 960–1279), and high in Ming (A.D. 1368–1644). In contrast, there were five PUWL phases in the coastal regions: high in Han (206 B.C.–A.D. 220), low in Jin-Northern & Southern Dynasties (A.D. 266–589), high in Tang-Song (A.D. 618–1279), low in Ming (A.D. 1368–1644), and high in Qing-Republic of China (A.D. 1644–1949). Yet, there were no apparent changes in PUWL in the transitional areas between the inland and the coastal regions. Regional hydrological factors cause the geographic variations of the PUWL fluctuations. Precipitation changes drove the rise and fall of PUWL in the inland areas. In contrast, the variations of PUWL in the coastal regions were attributed to the temperature-induced sea-level changes. This study illustrates the potential of using PUWL in tracing paleo-environment changes and their driving factors, which is a novel approach in environmental archaeology. |