渚滑川河口拦门沙演变特性

河口拦门沙的存在可导致径流流出不畅，并能引起一系列的河口生态及环境问题。特别是弯曲型河口，在波浪流、河川径流及弯道副流的共同作用下，拦门沙的形成及演变将更为复杂。通过对日本渚滑川河口多次实地调查资料的分析，揭示了渚滑川河口拦门沙的演变特性。结果表明：渚滑川河口修筑防波堤后，在东北方向的海洋入射波作用下，拦门沙由河口右岸发育并向左岸逐渐延伸扩展，其河水流动也相应由右岸偏向左岸一侧；不论河口有无拦门沙，3次洪水在右岸的最大冲深均稳定在-6m高程，且河床横剖面的形状基本不变，即汛期时该河口河床形状已达平衡状态。

Evolutionary characteristics of river mouth bar in the Shokotsu River

The bar in a river mouth is formed depending on the balance between river dynamics and ocean dynamics,when the river channel curves in a river mouth,the bar maybe evolute most complexly due to channel s curvature.In this paper,by analyzing a great deal of data obtained in-site,the evolutionary characteristics of the Shokotsu River mouth bar were clarified as:(1) due to the coupling action of the bulwark built in the mouth of Shokotsu River and incident wave with the direction of north-east,a river mouth bar occurs in the right bank originally,and gradually develops and extends toward left bank,accordingly the direction of the water flow varies from the right to left bank;(2) no matter river mouth bar exists or not,the elevation of the river bed keeps to a level of 6m after 3 times flood run out,that is,the bed form at the Shokotsu River mouth has been balanced between scouring and sediment in flood season.