Morphodynamic response of Xiaomiaohong tidal channel to a coastal reclamation project in Jiangsu Coast, China

Abstract

Zhang, C., Zheng, J.H., Dong, X.W., Cao, K. and Zhang, J.S., 2013. Morphodynamic response of Xiaomiaohong tidal channel to a coastal reclamation project in Jiangsu Coast, China.Xiaomiaohong tidal channel is located at the southern part of the large-scale radial sand ridge system along Jiangsu Coast, China. A land reclamation project was carried out on the tidal flat at the south bank of Xiaomiaohong channel in 2003, which led to the considerable change of channel morphology. This study aims to investigate the morphodynamic response of the tidal channel to the reclamation project through field observation and numerical modeling. Measured data shows that bed deposition occurred at both the east and west sides of the project area while erosion is found between the project area and the channel axis, especially around the northwest corner of the project area. The relationship between the observed bathymetry change and the reclamation project is discussed. A two-dimensional numerical model is developed to investigate the project effects on the tidal current, tidal volume, sediment concentration and morphological evolution. It is indicated that the change of morphodynamic processes due to the reclamation project is only concentrated near the project area and the project does not significantly influence the overall channel evolution. While the nearby current direction and velocity were changed and the tidal volume was reduced after the reclamation, sediment concentration was little affected. The model is able to qualitatively simulate some important evolution trend of the channel under the impact of reclamation project but some difference is also found with respect to the erosion/deposition intensity and scale.