广西溢油海域的浮游植物跟踪监测与比对分析

针对广西涠洲岛海域的突发溢油事件,于2008年9月下旬进行了溢油海域浮游植物跟踪监测,并与历史资料比对,探讨溢油对浮游植物群落的影响。调查中,共记录4门106种,硅藻92种,甲藻12种,蓝藻1种,着色鞭毛藻1种,主要优势种为旋链角毛藻(Chaetoceros curvisetus)、菱形海线藻(Thalassionema nitzschioides)和洛氏角毛藻(Chaetoceros lorenzianus)。浮游植物种类多,站间差异小,分布均匀。浮游植物细胞密度高,平均2 645.32×10⁴cells·m^-3,密集中心位于涠洲岛西北部海域。优势种密度分布与浮游植物细胞密度分布态势基本一致。多样性指数(H')和均匀度(J')均较高,群落结构稳定。与国家海洋局同期调查资料及相关文献报道比对,表明溢油海域浮游植物种类组成无较大变化,细胞密度有较小降幅,密集中心不同,优势种变更明显,群落结构稳定,应重视溢油应急反应的迫切性。

Sequential monitoring and contrastive analyzing of phytoplankton in oil spilling ocean in Guangxi

Monitoring of marine environment was conducted in Weizhou Island, Guangxi in late September, 2008 after an oil spilling event occurred, and community structure of phytoplankton was analyzed based on investigation data. The results showed that 106 species belonging to 44 genera were identified, including diatoms of 92 species in 35 genera, pyrrophyta of 12 species in 7 genera, cyanobacteria and chromophyta of 1 species in 1 genus each. The main dominant species included Chaetoceros curvisetus, Thalassionema nitzschioides and Chaetoceros lorenzianus. Distribution of phytoplankton was homogeneous. Average density of phytoplankton was 2 645.32×10~4 cells·m~(-3) with a relatively higher cell density in the northwest, lower in the southwest around Weizhou Island. Abundance distribution of dominant species was generally similar with phytoplankton density. Shannon-Wiener(H') and Pielou(J') indices indicated that phytoplankton community was stable. In contrast to other relative researches, reports and data from State Oceanic Administration, our results suggest that in oil spilling ocean phytoplankton composition varied little, and phytoplankton density decreased less. Main dominant species were obviously subrogated and community structure was stable. Quick response to oil spilling emergency in marine ecosystem must be required.