Temporal And Spatial Variation Of Erosion-Deposition And Morphological Evolution Of The Huanghe Delta Based On Numerical Model And Statistical Model

In this paper, a numerical model and a statistical model are applied to analyze the temporal and spatial variation of erosion-deposition and the morphological evolution of the Huanghe Delta. Firstly, a tri-nesting fluid dynamics & sediment transport numerical model considering the interaction of waves and currents is developed and adopted to study the sediment transport and morphological evolution in estuarine and coastal environments. Secondly, a EOF&ANN statistical model is developed to describe and forecast the topographic development of the Huanghe Delta. The analysis of the variation of erosion-deposition and the morphological evolution of the Huanghe Delta is also based on the variation of the water and sediment discharge and estuarine position of the Huanghe.With the two models some conclusions have been drawn as follows:1. The numerical model developed in this paper is effectively applied to simulate the waves, currents, sediment transport and morphological evolution in the nearshore sea of the Huanghe Delta. The results clearly reveal the response to the water-sediment discharge and estuarine position of the Huanghe of the pattern of the sediment transport and the morphological evolution in the study area. In the flood season, the deposition occurs in the current estuary and the erosion occurs in the old estuary. In the drought season, the erosion occurs in the most area. When the estuary of the Huanghe lies on the east-north of the delta, the deposition near the estuary would slow down compared with other position.2. With the EOF&ANN statistical model, the pattern of erosion-deposition can be well revealed and the morphological evolution can be forecasted in some degree. In term of space, the evolution of the Huanghe Delta has been centered on the oldand current estuaries. Near the discarded river mouth, the underwater shore slope is eroded with the influence of the waves and currents. Contrarily, in the current estuarine area, the water-sediment discharge from the Huanghe seasonally has made the shoreline extension outward. Otherwise, from the temporal point of view, both deposition and erosion are in a weakening trend. According to the future submarine topography calculated by the model, the whole delta is shrinking year by year.