Abstract: As the reconstruction of ship lock, the underwater topography has changed significantly. Obtaining high-precision deposition-erosion data is critical as it has a direct effect on safety and maintenance of water conservancy facilities. Based on the digital elevation model (DEM) established with underwater terrain data in 2012 and 2016, this paper has realized quantization and visualization of sediment transport. The result shows that the proportion of deposition and erosion area is almost the same. The deposition is about 2.127 8 million cubic meters, occupying 39.93% of the total area, mainly distributed over the land areas. While sediment erosion is the major phenomena for underwater area. The amount reaches 2.962 3 million cubic meters, occupying 52.58%.

Key words: underwater topography, digital elevation model, erosion and deposition

摘要： 随着船闸扩建工程的开展，富春江电厂坝下水底地形变化显著，冲刷淤积量的计算精度直接影响了对水下地形变化的评估，甚至涉及对水利设施安全维护工作更好地把控。利用2012年、2016年富春江流域部分河段水下地形图为基础资料，分别建立数字高程模型并进行叠合分析，实现对泥沙输移的定量化和可视化。结果表明：2012~2016年间，流域冲刷区、淤积区所占比重相当；淤积量有212.78万m3，占整个区域的39.93%，主要分布在地势较高的岛屿以及坝址东岸船闸扩建工程区；水下则以泥沙冲刷为主要现象，冲刷量达296.23万m3，面积比例为52.58%。

关键词: 水下地形, 数字高程模型, 冲刷淤积