金塘水道冲淤变化分析

Analysis on scouring and silting variation in the Jintang Channel

利用1935年、1962年、1987年和2004年4个典型年份的水深地形资料,通过建立这些年份金塘水道的数字高程模型,定量计算了不同时段海床平面冲淤和特征等深线位移的变化,并结合实测水文泥沙资料和南北两岸的水利水运工程布局,初步分析了冲淤变化的原因。结果表明,在1935—2004年的69年中,金塘水道的海床平面整体上以轻微冲刷为主,冲刷速率为2.3 em/a,而潮滩则表现为不断淤涨;水道冲淤在不同时段存在一定的差异,呈现由冲刷转向淤积的调整趋势,这种趋势可认为人为因素的作用大于自然环境因素的作用。

Based on 4 typical bathymetric maps of 1935, 1962, 1987 and 2004, the digital elevation model of the Jintang Channel was established to calculate the amount of variation in the erosion-deposition of seabed plane and the displacement of characteristic contour lines in different periods. Furthermore, the reasons of scouring and silting variation were preliminarily analyzed with observed hydrologic data and the layout of water conservancy ＆ waterway engineering in south and north shore areas. The result indicated that during the period of 1935-2004, the seabed plane of Jintang Channel was mainly characterized by slight scouring, of which the rate was 2.3 cm/a, while the tidal flat had been silting continuously. There were certain differences in the channel＇s scouring and silting in different periods, presenting a trend of change from erosion to deposition. This trend showed that the influence of human impacts was stronger than that of nature conditions.