A hydromorphic reevaluation of the forgotten river civilizations of Central Asia

• Published in: Proceedings of the National Academy of Sciences
• Main Authors: Willem H.J.Toonen, Mark G. Macklin, Giles Dawkes, Julie Durcan, Max Leman, Yevgeniy Nikolayev, Alexandr Yegorov
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2020
• Subjects: Central Asia; Mongol invasion; Aral Sea basin; irrigation; North Atlantic; North Atlantic oscillation
• Online Access: https://zenodo.org/record/8354889; https://doi.org/10.1073/pnas.2009553117

Our paper challenges the long-held view that the fall of Central Asia’s river civilizations was determined by warfare and the destruction of irrigation infrastructure during the Mongol invasion. An integration of radiometric dating of long-term river dynamics in the region with irrigation canal abandonment shows that periods of cultural decline correlate with drier conditions during multicentennial length periods when the North Atlantic Oscillation had mostly positive index values. There is no evidence that large-scale destruction of irrigation systems occurred during the Arab or Mongol invasion specifically. A more nuanced interpretation identifies chronic environmental challenges to floodwater farming over the last two millennia, punctuated by multicentennial-length periods with favorable hydromorphic and hydroclimatological conditions that enabled irrigation agriculturists to flourish.