珠江磨刀门河口悬沙浓度变化特征分析

根据2011年枯季和2012年洪季在大、中、小潮期间的多点同步现场观测资料,分析研究了磨刀门河口悬沙浓度变化特征。结果表明:磨刀门口悬沙浓度纵向分布呈近岸高,远岸低的趋势;横向分布具有季节性差异,洪季主槽大于滩地,枯季滩地大于主槽;垂向分布洪季主要以斜线型分布为主,枯季主要以抛物线型分布为主。潮周期平均含沙量大潮普遍大于中、小潮;洪、枯季磨刀门口外落潮含沙量普遍大于涨潮含沙量。洪季含沙量混合较为均匀,落潮时含沙量增大,涨潮时含沙量减小,枯季含沙量分层明显,。受波浪潮汐作用,一个周期内有多次明显的再悬浮过程,涨潮时增大,落潮时减小。

The study on suspended sediment transport mechanism in flood and the dry season in Modaomen Estuary of the Pearl River

This paper studies the characteristics of suspended sediment concentration according to the multi point synchronous observation data in spring tide,middle tide,neap tide in flood and dry season at Modaomen Estuary.The result shows that the longitudinal distribution of suspended sediment concentration of inshore is high while the offshore is low.The lateral distribution of suspended sediment concentration shows difference in different season that the suspended sediment concentration of main channel is higher than beach in flood season but the beach is higher in dry season.The vertical distribution of suspended sediment concentration looks like slash in flood season while parabola in dry season;the average sediment concentration in spring tide is higher than mid tide an neap tide,and it's larger at ebbing time than at flooding time.In flood season,the sediment concentration mixed evenly and increases at ebbing time while decreases at flooding time.In dry season,the sediment stratification is obvious and there are several significant resuspension process in a tidal period,which increases in flooding time and decreases at ebbing time.