19-3油田溢油对辽东湾浮游植物群落的影响

Influence of 19-3 Oil Spill Accident on Phytoplankton Community in the Liaodong Bay

关键词:  石油污染  辽东湾  浮游植物  群落结构  多样性指数

Key words:  Oil pollution  Liaodong Bay  Phytoplankton  Community structure  Biological diversity index

摘要:

根据2012-2014年对辽东湾浮游植物群落的调查，分析了19-3油田溢油事故发生后辽东湾浮游植物种类、细胞丰度、生物多样性和优势种的变化以及影响因素。调查发现，辽东湾浮游植物种类数在2012年有明显的降低，而在2013年和2014年浮游植物种类数明显上升。辽东湾浮游植物细胞丰度在夏季异常升高，中肋骨条藻(Skeletomema costatum)出现暴发性繁殖，这可能与海水中油类含量的升高有一定关系。

Abstract:

In this study we investigated the changes and contributing factors of species composition, cell abundance, biological diversity and dominant species of phytoplankton community in the Liaodong Bay, with emphasis on their correlation with the 19-3 oil spill accident in Penglai. Our analysis was based on the field data about phytoplankton community collected in the Liaodong Bay in May (Spring), August (Summer) and October (Autumn) from 2012 to 2014. It was found the number of phytoplankton species was the lowest in May 2012, and the highest in October 2013. Overall the number in 2012 was lower than those in 2013 and 2014. The cell abundance of the phytoplankton community rose unexpectedly in all three summer seasons. The maximum reached 3072×104 ind/m3 in August 2012, and the minimum (27×104 ind/m3) appeared in May 2012. The dominant species in different seasons were nearly unchanged between 2012 and 2014. The dominant species in May were Paralia sulcata, Chaetoceros, Noctiluca scintillans, and it was Skeletonema costatum in August. In October Coscinodiscus, P. sulcata, and Chaetoceros gained the dominance. Interestingly, S. costatum, a dominant microalga, underwent explosive reproduction in August 2012, which might be associated with the increased oil concentration in surface seawater in the Liaodong Bay. Correlation analysis was performed to explore the links between the environmental factors and parameters such as species composition, cell abundance, and biological diversity index. The results indicated that the alteration in phytoplankton community structure was significantly correlated with water temperature, COD, dissolved oxygen and nutrients. Furthermore, the community structure was also strongly affected by the oil concentration in surface seawater.