Wang, Q.; Zhan, Q.; Wang, L.; Zhan, C.; Cui, B.; Liu, X.; Li, X.; Wang, X.; Yu, X., and Zhang, J., 2020. Morphodynamic evolution of the Huaihe River estuary during the Huanghe River invasion from 1128 AD to 1855 AD. In: Zheng, C.W.; Wang, Q.; Zhan, C., and Yang, S.B. (eds.), Air-Sea Interaction and Coastal Environments of the Maritime and Polar Silk Roads. Journal of Coastal Research, Special Issue No. 99, pp. 250–256. Coconut Creek (Florida), ISSN 0749-0208.

Based on historical records, we investigated the dynamic conditions, geomorphological characteristics, and evolution mechanisms of the Huaihe River estuary during the period of Yellow River invasion. The results showed that the runoff and sediment discharge of the Huaihe River increased owing to a large quantity of sediment-laden runoff into the Yellow River from 1128 to 1855 CE. However, the sediment discharge in different periods is also affected by repeated siltation along the lower reaches of the Yellow River. Huaihe estuary is a tidal estuary with moderate intensity. Its reciprocating tidal current and coastal current system are favorable to the discharge of sediment into the sea. The shape of the Huaihe estuary is narrow on the upper side and wide on the lower side. Large-scale sandbar and underwater delta were developed in the inside and outside of the estuary, respectively. The channel of the estuary has a typical curved river type, and the width of the estuary has had an increasing trend since the 18th century. The evolution mechanism of the Huaihe estuary is that the tidal current limit continuously moves downstream, and the estuary continuously extends to the sea. In addition, the downstream movement distance of the tidal current limit is much longer than that of the outward extension of the estuary during the same period, resulting in a significant shortening of the estuary section. To satisfy the energy demand by runoff and tidal current, the river type of the estuary section becomes meandering and the entrance is widened. The ancient Huaihe River estuary and the modern Yellow River estuary have different dynamic geomorphological characteristics and evolution mechanisms, which cannot be simply analogized.