Clues to flocculation development by comparing particle size distribution patterns of suspended matter in the water mixing zone of the Changjiang River Estuary  

作　　者：Yue Pang Xiaoxia Sun Xueshi Sun Ming Liu Dejiang Fan 

机构地区：[1]Laoshan Laboratory,Qingdao 266061,China [2]Key Laboratory of Submarine Geosciences and Prospecting Techniques,Ocean University of China,Qingdao 266100,China [3]Laboratory for Marine Geology,Qingdao Marine Science and Technology Center,Qingdao 266100,China

出　　处：《Acta Oceanologica Sinica》2024年第12期66-74,共9页海洋学报(英文版)

基　　金：The National Natural Science Foundation of China under contract No.42176077。

摘　　要：Particle size is an important characteristic of suspended matter,and it contains crucial information about the deposition process.Suspended particle samples in the water mixing zone of the Changjiang River Estuary were collected in December 2016.Untreated original grain size and the decentralized grain size of the suspended particles were measured via a laser particle size analyzer.Morphological characteristics and the chemical composition of the suspended particles were also studied systematically using a scanning electron microscope(SEM)with an energy dispersive X-ray spectrometer(EDS).Then,the flocculation and sedimentation of suspended matter in the water mixing zone were explored by combining them with the water mixing processes in the estuary.The average particle size of suspended matter in the mixing zone of the Changjiang River Estuary ranges fromФ5.73 toФ7.98.The particle size distribution pattern is an abnormal model with a mainly unimodal pattern.In the freshwater area that was dominated by runoff,the suspended matter is mainly composed of fine particles,the settling velocity is slow,and the flocculation is weak.Floc particles were often seen in the mixing zone,with the flocs having a relatively large particle size,a low density and a loose structure appearing at the weak mixing zone;the flocs had a compacted structure in most areas of the mixing zone.The changes of suspended particle size in the estuarine mixing zone promote the settling and deposition of suspended matter,which has an important influence on the bed geomorphology and preservation of the fine suspended particles in the estuary.

关 键 词：water mixing zone suspended matter particle size SEDIMENTATION FLOCCULATION Changjiang River Estuary 

分 类 号：P343.5[天文地球—水文科学] P737.121[天文地球—地球物理学]