在珠江三角洲网河区河道上联围筑闸,或在口门滨海地带进行较大面积的海滩围垦工程以后(以下简称工程后),会导致外江水文情势发生某种程度上的变化。如在河道上联围筑闸,水闸控制运用时,闸前外江的最高洪(潮)水位和最低水位的 The construction of a floodgate along the river network in the Pearl River Delta or the reclamation of a large area of ​​beach at the port coastal area (hereinafter referred to as the “Project”) will lead to a certain degree of change in the hydrological conditions in the outer river. For example, if a gate is built around a river and the gate is under control, the highest flood (tide) and lowest water level