广东沙扒潮汐汊道口门地貌现代演变

CONTEMPORARY GEOMORPHIC EVOLUTION OF THE ENTRANCE OF SHAPA TIDAL INLET, GUANGDONG

沙扒及其上游儒洞湾是一个有一定规模,比较稳定的河口湾型潮汐汊道,在波浪与潮流共同作用并以潮流为主的动力条件下,口门地区发育有潮流深槽、涨槽三角洲、水道边缘坝、拦门沙浅滩、边缘涨潮水道及内弯沙嘴等地貌类型。近年来,各种人类活动引起水文泥沙条件变化,导致东槽萎缩、西槽复苏、南槽转向、拦门沙东移并靠岸、港南沙嘴变低内移等现代演变过程。在港口现划与整治时必须对此充分考虑。

Shapa tidal inlet is a comparatively stable inlet of estuarine type with broad waters. The tidal channel, flood-tidal delta, channel-margin bar, mouth bar, marginal flood channel, and recurved spit are the main geomorphic elements in the entrance area of the inlet under the effects of waves and tidal currents(tided-dominated). In recent years, activities by mankind have caused changes in hydrodynamical conditions and sediment transport, resulting into a series of geomorphic evolution processes such as the shallowing of the east channel,deepening of the west channel, direction change of the south channel, the eastward and landward movement of the mouth bar, and the lowering of the spit in the south of the fishery harbour as well as its movement towards the harbour. These processes must be fully considered in harbour planning and development.