渤海湾海域生态环境的研究Ⅱ.水体富营养化的评价与分析

根据2003年7月15日、2003年11月4日、2004年2月29日和2004年5月25日在渤海湾多项生态因子的调查结果,应用单因子法和综合指数法对该海域海水的质量状况进行了评价与分析,并与历史资料进行了比较.结果表明,渤海湾水体整体呈现富营养化,主要为无机氮严重超标;另外,春季水体有机污染较为严重,秋季无机磷含量也达到富营养水平.无机氮、无机磷、COD以及营养状态指数(EI)的时空分布大体呈现北高南底,近岸大于外海的趋势,分布趋势与历史资料基本吻合,但比历史同期无机氮、COD浓度增加,水体富营养状态呈现愈发严重的趋势.

Study on ecological environment in the Bohai Bay Ⅱ. Assessment of coastal eutrophication

Based on the survey data of many ecological factors on Jul. 15, 2003, Nov. 4, 2003, Feb. 2 9, 2004 and May 25, 2004 in the Bohai Bay, the assessment and analysis of the quality state of sea water in this area were made Using the single factor and composite index method, and comparing with the historical materials. The result showed that the waters in Bohai Bay present eutrophication wholly, mainly exceed seriously the standard in nitrogen salt. In addition, the organic pollution in water is comparatively high in spring, the content of PO4-P reaches the eutrophication level too in autumn. DIN, PO4-P, COD and E1 appear high in south bottom and north, and greater offshore than in the open waters. The trend of distribution is basically identical to historical materials. But DIN, COD density are increased in the same period of history, and the eutrophication state in water is more and more serious.