长江口海域表层沉积物环境质量的综合评价

THE COMPREHENSIVE ASSESSING OF SURFACE SEDIMENTS ENVIRONMENTAL QUALITY IN CHANGJIANG ESTUARY INSHORE

利用2004年和2009年夏季航次长江口海域表层沉积物的监测统计结果，以加权平均环境质量综合指数法为基础，以参评因子动态分类排序法确定权重，以《海洋沉积物质量》（GB18668—2002）作为评价标准，构建新的海洋沉积物质量综合评价模式，对长江口海域表层沉积物中的主要污染因子进行了分类判别，综合评价了长江口海域表层沉积物质量状况。结果表明，长江口海域表层沉积物中硫化物、石油类、汞为常态因子，铅、镉、砷、多氯联苯和滴滴涕为关键因子，铜和有机碳在个别站位已成为预警因子；沉积物环境质量总体良好，综合评价指数介于0．267～0．636之间，均属于第一类海洋沉积物质量；个别站位铜、有机碳含量偏高，存在超标现象。此外，本文通过构建的海洋沉积物质量综合评模式计算过程简单、权重确定不受人为主观因素的影响、反映沉积物综合质量的时空变化特征比较客观，具有普适性。

By using of the monitoring-statistical results of surface sediments quality of Changjiang Estuary inshore in summer of 2004 and 2009, on the base of the weighted average environmental quality comprehensive index method, to determine the weight by applying improved analytical hierarchy process method, with the marine sediment quality as evaluation criterion, the new comprehensive evaluation model of marine sediment quality was constructed.The classifying of main pollution factors in surface sediments of Changjiang Estuary inshore was performed, and a comprehensive assessment was given on surface sediments environmental quality with using of the new evaluation model constructed. The assessing results showed that Sulfides, Oil, and Hg were Normal Factor, Pb, Cd, As, PCBs, and DDTs were Pivotal Factor, Cu and TOC were Warning Factor in surface sediments of Changjiang Estuary inshore. On the whole, the surface sediment environmental quality was generally good, the comprehensive evaluation index was between 0.267 to 0.636, the comprehensive environmental quality of all the surface sediment samples in Changjiang estuary was at grade marine sediments quality levelthe content of Cu and TOC in individual stations was exceededgrade marine sediments quality level. Moreover, with a simple calculation progress of the constructed marine sediment quality comprehensive assessing model simple, and the factors weights in this model affected by artificial subjective factors, it is more objective to reflect spatial variation characteristics about marine sediment comprehensive environmental quality, and this comprehensive assessing model is with being universal.