中文摘要：

应用近几年的水文和地形实测资料，研究了磨刀门拦门沙区域近期的动力和地貌演变特点。近期地貌演变的主要特点为：深槽外移扩展，一主一支分汊明显；拦门沙内坡冲刷外移，外坡变化不大，纵向宽度变窄；拦门沙西区淤积，拦门沙中心区和拦门沙东区冲刷；地貌轴线总体向南和西南方向偏转。从水动力和地貌演变的角度来看，磨刀门拦门沙区域航道整治应关注下列问题：1）注意河口性质的变化，着重解决径流输沙，波流共同输沙这两个主要问题；2）在工程布置中，应与口门外动力场的特点和地貌演变的总体趋势相适应，以建设双导堤为宜；3）西汉、东汊均是可选择的航线，从综合因素考虑宜选择西汉；4）注重河E1分汉的自然规律，注意保护东支汉；5）注意稳定拦门沙中心区。

英文摘要：

Hydrographic and bathymetric data have been applied to review the dynamic regime and morphological evolution in recent years in the sandbar area of the Modaomen estuary. The main characteristics of the morphological evolution in the sandbar area in recent years are as follows： （ 1 ） the deep trough was extended toward sea and expanded, and was bifurcated into main stream and tributary; （2） the inner slope of the sandbar was scoured and moved outward, the outer slope was little changed, and the longitudinal width of the sandbar became narrow; （3） the western part of the sandbar was accreted while the middle part and eastern part were scoured; （4） in general, the axis of the topography in the sandbar area was turned toward south and south-west. In view of the hydrodynamic and morphological evolution, conclusions are made： （ 1 ） while considering the change of the estuary nature, sediment transport by runoff as well as jointly by wave, littoral current and tidal current should be focused on; （2） the engineering arrangement should be done based on the dynamic field and tendency of the morphological evolution, and the double training dikes are preferred; （3） both eastern tributary and western tributary are the potential route for waterway, and the western tributary may be better considering different factors; （4） the eastern tributary should be protected due to the natural rule of bifurcation of the estuary; （5） the middle part of the sandbar should be stabilized.