中文摘要：

根据江苏连云港航道扩建工程南临时倾倒区面积及其影响海域范围,在疏浚泥倾倒前后,在该倾倒区布设5个断面,每个断面设3个站位,即水质站位15个、沉积物站位15个、生物站位15个,对水质、沉积物、生物进行监测分析。结果表明：倾倒后,各个站位的DO受到不同程度的污染;高锰酸盐指数低于《海水水质标准》（GB 3097—1997）中的二类海水水质标准;无机氮最大值超出二类海水水质标准;磷和BOD5有所升高;倾倒使水体中石油类物质的含量大幅上升,显著高于倾倒前,反映了石油类物质污染对水体的影响时间较长;疏浚泥倾倒使水体中铅和镉的含量显著上升;叶绿素a有下降的趋势,影响浮游植物的正常生长;疏浚泥倾倒对该海域浮游植物的组成影响不大,浮游植物群落结构较合理,结构基本稳定,倾倒后该海域环境尚适宜浮游植物的生长;倾倒前该海域的底栖生态环境较好,倾倒后总体属于轻度污染状况,说明疏浚泥海洋倾倒对倾倒区底栖生态环境有一定影响。

英文摘要：

5 sections（3 position sites per section）,15 water quality sites,15 deposit sites and 15 biological sites were set up in Lianyungang dumping area to monitor the variation of marine water quality,deposit and biology diversity after dredge mud dumping.Base on the monitor results,the safety evaluation of dredge mud dumping in on marine environment was conducted.Results showed that DO was contaminated to varying degrees after dredge mud dumping;the variation of permanganate index was unnoticeably,inorganic nitrogen extra-standardization;phosphor,BOD5,petroleum,heavy metals such as Pb and Cd were increased significantly,while the content of chlorophyll a presented decreasing tendency.The influence of dumping on phytoplankton was negligible;the community structure of phytoplankton was rational and stable.The benthic ecology environment belongs to low-grade pollution after dumping,indicated that dumping impact the bottom habitat to a certain degree.