【摘要】 从排洪通道、航运通道、排水通道的形成以及浅滩围垦等方面阐述磨刀门10 a综合整治的效果。口门延伸、 平原扩展及地貌类型、沉积构造及冲淤变化反映了近20多年来磨刀门从浅海湾演变为三角洲的过程。“磨刀门外 水下三角洲”未来的发展趋势受沉积基础、水动力条件、泥沙运动和沉积作用的影响。由于水动力从径流优势型转 变为径流-潮流优势型,沿岸流、风暴潮、波浪的作用增强,使得口外海域的滩槽向西南方向延伸。未来“磨刀门外 水下三角洲”治导线的布设应为南偏西,并保持大喇叭口态势。更多还原

【Abstract】 About one- third of runoff and stream load from Zhujiang Delta is transported into the sea area through Modaomen river mouth. Therefore the administration of Modaomen is of a decisive position to ensure the flood discharge safety in Zhujiang Delta. A program of dredging Modaomen river mouth has been carried out essentially from 1984 to 1995 and acquired obvious effects for discharging flood,shipping,drainage and reclamation. During the recent 20 years, the Modaomen shallow estuary became"Modaomen delta"in which the area of plain accounts for 77%. The Modaomen river mouth is extending to sea area outside the estuary,and thus a "Modaomen submerged delta"is forming. The runoff dynamics is still dominant but the influence of hydrodynamics such as coastal current,storm tide and wave becomes stronger. Due to the changes of depositional basis, hydrodynamics condition,silt movement and sedimentation, the" Modaomen submerged delta"may transform from runoff-dominated type to runoff- tidal dominated type,and the extending tendency of the delta may be westward. The arrangement direction of dredging lines in future should be inclined to south -west and to preserve the situation like a large bell.更多还原