溢油事故对河口滩涂大型底栖动物群落的影响

Stress of Oil Spill on Community Structure of Benthic Macroinvertebrate in the Estuarine Tidal Marshes

为了解2012年末发生的船舶溢油事故对底栖动物群落结构的影响及其生态恢复情况,文章分别于溢油事故应急处置后(2013年3月)及二次处置1 a后(2015年3月)对受事故影响较大的崇西边滩6个站点的大型底栖动物进行了调查,研究溢油后其群落结构特征及动态变化,并进行生物多样性分析。结果表明,2次调查分别鉴定出大型底栖动物11种和12种,分属4门7纲,优势种群和优势种分别为环节动物、疣吻沙蚕及甲壳动物、谭氏泥蟹;平均密度和生物量呈上升趋势,但无显著差异;Shannon-Wiener指数<1,Pielou指数<0.3,表明研究区受污染严重,区域内底栖动物种间分布不均匀。虽在2次处置后底栖动物群落在一定程度上得到了恢复,生境有所好转,但溢油污染的胁迫和处置活动的扰动仍将持续影响研究区底栖生态环境。

In order to understand the influence of the oil spill occurred at the end of 2012 on the community structure of benthic macroinvertebrates and its recovery, the benthic macroinvertebrates in six stations on tidal marshes in the west of Chongming Island, Shanghai were collected respectively after emergency disposal(in March 2013) and one year after secondary restoration(in March 2015). The characteristics, dynamic variation and biodiversity of the community structure after the oil spill was researched. The results showed that 11 and 12 benthic macroinvertebrates were identified respectively, belonging to 4 phyla and 7 classes. The dominant population and species were annelida, Tylorrhynchus heterochaetus and crustacean,Ilyoplax deschampsi respectively. The mean density and biomass showed an upward trend, with no significance. The Shannon-Wiener index and Pielou index were lower than 1.0 and 0.3 respectively, showing the seriously-polluted environment and the unevenly-disturbed community in the study area. Although the community structure of benthic invertebrate was restored and the habitat has improved to some extent, the oil spill and treatment activity will affect the habitat of the research area continuously.