杭州湾海域水质中石油类的分布特征

文章利用2017—2019年杭州湾海域12个航次的水质监测资料，分析水质调查项目中石油类的分布特征。研究结果表明：2017—2019年杭州湾海域水质石油类含量范围分别为0.008～0.042 mg/L、0.011～0.046 mg/L、0.007～0.094 mg/L,年度平均含量分别为0.023 mg/L、0.023 mg/L和0.016 mg/L,均满足第一类海水水质标准。在季节变化上，水质中石油类指标由于受潮流、含沙量及风力等物理因素影响表现不明显，均属于低含量下的波动。在年际变化上，2017年和2018年石油类含量总体相当，2019年相比前2年有显著降低，具有一定的下降趋势。在平面分布上，主要呈现为多点源分布，高值区主要出现在嘉兴近岸和杭州湾南岸。通过相关性分析研究发现，石油类含量与悬浮物呈显著负相关，海水中悬浮物对石油类污染物有吸附作用，海水中悬浮物的质量越大，石油类含量越低。

Distribution Characteristics of Petroleum in Water Quality of Hangzhou Bay

Based on the water quality monitoring data of 12 voyages in Hangzhou Bay from 2017 to 2019, the distribution characteristics of petroleum in the water quality survey project were analyzed. It was found that the content range of petroleum in the waters of Hangzhou Bay were 0.008~0.042 mg/L, 0.011~0.046 mg/L, 0.007~0.094 mg/L respectively, from 2017 to 2019, and the annual average content were 0.023 mg/L, 0.023 mg/L and 0.016 mg/L, all met the Class I sea water quality standard. In terms of seasonal change, the petroleum indicators in water quality were not obvious due to the influence of physical factors such as tidal current, sediment content and wind force, and they all belonged to fluctuations at low contents. In terms of interannual changes, the petroleum pollutants content were generally the same in 2017 and 2018, compared with the first two years, there was a significant decrease in 2019, with a certain downward trend. In terms of plane distribution, it mainly presented multipoint source distribution, and high value areas mainly appeared in coastal waters of Jiaxing and the south coast of Hangzhou Bay. Through correlation analysis and research, it was found that the content of petroleum was significantly negatively correlated with the suspended solids. The suspended solids in seawater had adsorption effect on petroleum pollutants, Thus the greater the mass of suspended solids in seawater, the lower the content of petroleum.