Research Center for Eco-Environmental Engineering, Dongguan University of Technology, Dongguan 523808, PR China.
State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China.
Comp Biochem Physiol C Toxicol Pharmacol. 2024 Oct;284:109992. doi: 10.1016/j.cbpc.2024.109992. Epub 2024 Jul 29.
The exploration of sediment pollution caused by PAHs and its impact on microbial communities can provide valuable insights for the remediation of sediments. The spatial distribution of PAHs and their impact on the microbial community within the Pearl River Estuary were investigated in this study. The findings revealed that the total concentration ranges of 16 PAHs were between 24.26 and 3075.93 ng/g, with naphthalene, fluorene, and phenanthrene potentially exerting adverse biological effects. More PAHs were found to accumulate in subsurface sediments, and their average accumulation rates gradually decreased as the number of rings in PAHs increased, ranging from 180 % for 2-ring to 36 % for 6-ring. The phyla Proteobacteria, Bacteroidetes, Actinobacteria, and Chloroflexi were found to dominate both surface and subsurface sediments The correlation between microbial genera and PAHs contents was weak in sediments with low levels of PAHs contamination, while a more significant positive relationship was observed in sediments with high levels of PAHs contamination. The physicochemical properties of sediments, such as pH, soil structure and Cu significantly influence bacterial community composition in highly contaminated sediments. Additionally, the network analysis revealed that certain bacterial genera, including Novosphingobium, Robiginitalea and Synechococcus_CC9902, played a pivotal role in the degradation of PAHs. These findings are significant in comprehending the correlation between bacterial communities and environmental factors in intertidal ecosystems, and establish a scientific foundation for bioremediation of intertidal zones.
本研究探讨了珠江口沉积物中多环芳烃（PAHs）的污染及其对微生物群落的影响，为沉积物修复提供了有价值的参考。研究发现，16 种多环芳烃的总浓度范围为 24.26-3075.93ng/g，萘、芴和菲可能具有生物毒性。更多的多环芳烃在底泥中积累，其平均积累率随着环数的增加而逐渐降低，从 2 环的 180%到 6 环的 36%。变形菌门、拟杆菌门、放线菌门和绿弯菌门在表层和底泥中占主导地位。在低水平多环芳烃污染的沉积物中，微生物属与多环芳烃含量之间的相关性较弱，而在高水平多环芳烃污染的沉积物中，两者之间存在更显著的正相关关系。沉积物的理化性质，如 pH 值、土壤结构和 Cu，显著影响高度污染沉积物中细菌群落的组成。此外，网络分析表明，某些细菌属，如新鞘氨醇单胞菌属、鲁棒假单胞菌属和聚球藻属 CC9902，在多环芳烃的降解中发挥了关键作用。这些发现对于理解潮间带生态系统中细菌群落与环境因素的相关性具有重要意义，为潮间带的生物修复奠定了科学基础。
