Temporal And Spatial Erosion And Deposition Evolution Of The Huanghe Delta And Its Numerical Modeling

In this paper, with years of measured water depth data, the empirical orthogonal function(EOF) method is applied to analyze the temporal and spatial evolution of the Huanghe delta. Then a numerical model is developed to simulate the sediment transport and erosion/deposition pattern around the modern Huanghe delta. In the numerical modeling, firstly, the SWAN model is adopted to develop a hydro-dynamical model considering the wave-current interaction. Then combined with a dynamical sea-bed model, a 2-D model of sediment transport with "moving boundaries" is founded. It is applied to the coastal area around the Huanghe delta in large scale.With the numerical modeling study of the law of erosion/deposition and evolution of the Huanghe delta, some conclusions have been drawn as follow:1. The erosion/deposition evolution pattern of the Huanghe delta can be well revealed with the EOF analysis method. In the term of space, the estuarine area is the deposition part while it's mainly in erosion around the northern delta shoreline at the end of Diaokou inflow. Otherwise, from the temporal point of view, both deposition and erosion are in a weakening trend.2. The complex hydro-sed model developed in this paper has proved effective. The results can clearly reveal the response to the water-sand discharge and ocean dynamics of the erosion/deposition pattern in the study area, esp. of the deposition outside the river mouth. In term of space, the evolution of the Huanghe delta has been centered on the old and current estuaries. Near the discarded river mouth, the erosive and modifying effect of wave is quite important. Thus, the underwater shore slope is in constant modulation in this area. Contrarily, in the current estuarine area, the water band sediment discharge from Huanghe seasonally has made the shoreline extension outward. The result mentioned above complies with the years of measured data.