摘要
运用通量机制分解法处理兴化湾各测站的水沙实测资料,通过探讨平流输沙、潮泵效应输沙、垂向净环流输沙机理,分析研究了兴化湾海域悬沙输移特征,进而讨论了净输沙对研究区域地形变化的影响。结果表明:在潮汐作用下,外海泥沙沿兴化水道与南日水道向湾内输移,但对湾内淤积产生的影响较小;平流输沙和垂向净环流输沙对悬沙的净输移起主要作用,水深相对较大的区域主要受平流输沙的控制,而浅水区垂向净环流输沙影响更强;潮泵输沙以悬沙与潮流变化相关项为主,输沙量小于平流输沙和垂向净环流输沙的输沙量;浅水区垂向各层余流方向不一致,悬沙各层混合均匀,深水区表底层的余流方向基本一致,含沙量垂向变化明显;输沙造成湾顶淤积,造成海湾地形变化的主要原因是陆源泥沙。
Based on the calculation of the tide and sediment data measured in the Xinghua bay by use of the mechanism decomposition method,the characteristics of the suspended sediment transport in the Xinghua bay have been illustrated through exploring the mechanism of the advection,tidal pumping effects and the vertical circulation for sediment transport,and the impacts of the sediment transport on the topographic changes in the study area have been discussed in this paper. The analysis results show： offshore-sediment moves toward the inner of the bay along the Xinghua and Nanri channels under the action of tide,but it has little influence on the sedimentation in the inner of the bay. The advection and the vertical circulation are the primary factors for the suspended sediment transport,and the sediment transport in the deeper region is mainly controlled by the advection while the vertical circulation has a stronger impact in the shallow regions. The sediment transport under tidal pumping effect is dominated by the correlation between the suspended sediment and the tidal current,which is less than the sediment transport caused by the advection and the vertical circulation. The residual current directions are inconsistent in different vertical layers in the shallow estuary region,which causes the suspended sediment to mix well. The directions of the residual current in the surface and bottom layers are basically the same in the deeper region,and the vertical sediment concentration changes significantly. The deposition in the top of the bay is caused by the sediment transport. The main cause of the changes in the gulf topography is terrigenous sediment.
出处
《水利水运工程学报》
CSCD
北大核心
2016年第2期1-10,共10页
Hydro-Science and Engineering
基金
国家自然科学基金重点资助项目(51339005)
国家自然科学基金青年基金资助项目(51409094)
关键词
通量机制分解法
悬沙输移
平流输沙
潮泵效应
垂向环流
mechanism decomposition method
suspended sediment transport
advection sediment transport
tidal pumping
vertical circulation
