Department of Biology & CESAM, University of Aveiro, Aveiro, Portugal.
Department of Chemistry & QOPNA, University of Aveiro, Aveiro, Portugal.
J Appl Microbiol. 2019 Jul;127(1):134-149. doi: 10.1111/jam.14261. Epub 2019 May 20.
To evaluate the interactive effects of oil contamination and chemical dispersant application on bacterial composition and sediment remediation of an estuarine port environment.
A multifactorial controlled microcosm experiment was set up using sediment cores retrieved from an estuarine port area located at Ria de Aveiro lagoon (Aveiro, Portugal). An oil spill with and without chemical dispersant addition was simulated. Sediment oil hydrocarbon concentrations and benthic bacterial community structure were evaluated by GC-MS and 16S rRNA high-throughput sequencing respectively. Although initially (first 10 days) chemical dispersion of oil enhanced the concentrations of the heavier polycyclic aromatic hydrocarbons and of the C -C alkane group, with time (21 days), no significant differences in hydrocarbon concentrations were detected among treatments. Moreover, no significant changes were detected in the structure of sediment bacterial communities, which mainly consisted of operational taxonomic units related to hydrocarbon-contaminated marine environments. We hypothesize that the environmental background of the sampling site preconditioned the communities' response to additional contamination.
This experimental microcosm study showed that the chemical dispersion of oil did not influence sediment remediation or bacterial community composition.
Our study showed that chemical dispersion of oil may not improve the remediation of port sediments. Further studies are needed to investigate the impact of chemical dispersants in combination with bioremediation strategies on the process of sediment remediation in port areas.
评估油污污染与化学分散剂应用对河口港环境细菌组成和沉积物修复的交互影响。
本研究采用多因素控制微宇宙实验，使用取自葡萄牙阿威罗泻湖河口港地区的沉积物岩芯。模拟了有和没有化学分散剂添加的溢油情况。通过 GC-MS 和 16S rRNA 高通量测序分别评估了沉积物中油烃浓度和底栖细菌群落结构。尽管最初（前 10 天）化学分散剂增加了重多环芳烃和 C-C 烷烃组的浓度，但随着时间的推移（21 天），处理之间的烃浓度没有显著差异。此外，沉积物细菌群落的结构没有明显变化，主要由与受烃污染的海洋环境相关的分类操作单元组成。我们假设采样地点的环境背景预先决定了群落对额外污染的反应。
本实验性微宇宙研究表明，油的化学分散剂并不影响沉积物修复或细菌群落组成。
我们的研究表明，化学分散剂可能无法改善港口沉积物的修复。需要进一步研究化学分散剂与生物修复策略相结合对港口地区沉积物修复过程的影响。
