浅海悬沙浓度观测方法的对比研究  

SUSPENDED SEDIMENT CONCENTRATIONS IN SHALLOW SEA: COMPARATIVE STUDY OF METHODS

作　　者：魏晓[1] 汪亚平[1] 杨旸[1] 陈坚[2] 高建华[1] 王爱军[2] 李东义[2] 胡国栋 

机构地区：[1]南京大学海岸与海岛开发教育部重点实验室,南京210093 [2]海洋与海岸环境地质开放实验室国家海洋局第三研究所,厦门361005 [3]长江水利委员会长江口水文水资源勘测局,上海20013

出　　处：《海洋地质与第四纪地质》2013年第1期161-170,共10页Marine Geology & Quaternary Geology

基　　金：国家自然科学基金项目(40876043);江苏省自然科学基金项目(BK2010050)

摘　　要：在动力和沉积条件复杂的浅海海域获取水-体的悬沙浓度有多种方法,目前较先进的主要是声学和光学浊度测量方法,但均需通过现场采集水样进行浊度标定;水样的分析方法主要有抽滤法和沉淀干燥法。根据2010年3—4月在厦门九龙江口获取的光学(OBS、LISST-100X)和声学(ADCP、ADP和ADV)浊度数据,以及现场同步水样,对这两种获取悬沙浓度的方法进行了比较;2011年2—3月在长江口北支获取水样,分别使用抽滤法和沉淀干燥法获取悬沙浓度数据进行比对分析。结果表明,声学和光学方法都具有较高的精度,在同一观测层位,光学与声学仪器的相对误差均较小;由于声波在水体中传播距离较远,声学方法可获得沿水深的整个剖面的信息,因而比光学仪器具有更高的空间分辨率和测量范围。对比发现,抽滤法获得的悬沙浓度数值略低于沉淀干燥法获得的结果,可能与沉淀干燥法难以洗净盐分有关。Various methods were used to measure the suspended sediment concentrations （SSCs） in the Jiulong Estuary in March, 2010 and in the North Branch of Yangtze Estuary in February, 2011. The synchronous acoustics and optical data including OBS, LISST-100X, ADCP, ADP and ADV were obtained by profiling and seabed tripod measurements. During these surveys, water samples were collected from the water columns form the sea surface down to the bottom, and then the SSC was retrieved by filtration in the lab. Distinctions were discerned among the above methods. Firstly, the seawater filtration is a benchmark method. Secondly, SSCs could be successfully and accurately estimated from acoustic and optical instruments installed at the same height above the seabed, with small measurement errors. Hence, they can be replaced each other, as a case of complementary measurement. Finally, the settling method may overestimate the SSCs, comparing to the filtration method due to the saline substance remained in the sediments. Thus, in order to estimate better SSCs, a suitable method should be selected according to the study pur pose and local SSC background.

关 键 词：浊度 海水过滤 悬沙浓度 九龙江口 长江口北支 

分 类 号：P716[天文地球—海洋科学]