海河口近岸海域2005-2010年间水环境变化分析

通过分析海河口及其邻近海域2005-2010年进行的多次环境现场调查资料,同时结合历史数据进行对比分析,结果表明:(1)河口水体中COD、BOD5、氨氮是突出污染因子,海河口水体污染程度整体呈现先降低再升高的趋势而大沽排污河河口区域水质状况相对更差整体仍然呈现进一步恶化态势;邻近海域水体中无机氮为最主要污染物,而其中硝酸盐是无机氮中最主要组成部分,不过亚硝酸盐所占比例正在逐年升高,说明区域水体氧化还原环境潜在变化正在发生;(2)丰水期陆源大量无机氮输入使得区域水体大部分时间超该区域功能区划要求的Ⅳ类海水水质标准;不过底质沉积物环境相对比较稳定,各监测项目全部符合一类海洋沉积物质量标准要求;(3)与1983年历史监测数据相比,海河口邻近海域活性磷酸盐、无机氮含量增速迅猛,丰水期时最高增幅活性磷酸盐和无机氮分别高达了2430%和5919%;整体看来同一时期水质和底质环境有缓和趋势,但潜在威胁仍然严重;最后,在认真分析对海河口及其邻近海域造成污染的各污染源基础上,进一步提出了有针对性的对策建议。

ASSESSMENT AND ANALYSIS OF ENVIRONMENTAL STATUS AND VARIATION TREND IN HIGH WATER PERIOD OF THE HAIHE ESTUARY AND ITS COASTAL SEA AREAS

Based on the analysis of the large quantity of monitoring materials on Haihe Estuary,the Dagu Drainage Estuary and its coastal sea areas from 2005 to 2010,and also the historic data of this area was compared and assessed.The results shown that(1) COD,ammonia nitrogen and BOD5 in the water of the Haihe Estuary and Dagu Estuary seriously exceeded the fifth sort of environmental quality standards for surface water and the second sort of sewage discharge standard respectively.At the same time,IN was the major pollutants in the costal sea areas and the proportion of the nitrite in IN was yearly increasing.The phenomenon predicted that the oxidation-reduction context was changing;(2) A great deal of land-sourced IN pollutants poured into the coastal sea areas and this resulted in the water standard being in the inferior fourth sort of national water quality.But corresponding to the enormously changing of water environment,the sedimentary environment was relatively stationary;(3) Compared with the historic data of 1983,the current concentration of IN and phosphate in high water period made an increase of 2430% and 5919% separately.Although the water and sediment quality appeared a relaxed trend in the larger pollutants,there still existed serious threat;Finally,on the basis of the analysis on the pollutant source,some pointed countermeasures and suggestions were put forward for the relevant oceanic administrative departments.