CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, Guangdong, China.
National Engineering Research Center of Gas Hydrate Exploration and Development, Guangzhou Marine Geological Survey, Guangzhou 511458, China.
J Hazard Mater. 2024 Dec 5;480:135760. doi: 10.1016/j.jhazmat.2024.135760. Epub 2024 Sep 8.
Chlorinated paraffins (CPs) and microplastics (MPs) are commonly found in deep-sea cold seep sediments, where nitrogen cycling processes frequently occur. However, little is known about their combined effects on sedimentary microbial communities and nitrogen cycling in these environments. This study aimed to investigate the synergistic impacts of CPs and MPs on microbial communities and nitrogen cycling in deep-sea cold seep sediments through microcosm experiments. Our results demonstrated that the presence of CPs and MPs induced significant alterations in microbial community composition, promoting the growth of Halomonas. Furthermore, CPs and MPs were found to enhance nitrification, denitrification and anammox processes, which was evidenced by the higher abundance of genes associated with nitrification and denitrification, as well as increased activity of denitrification and anammox in the CPs and MPs-treatment groups compared to the control group. Additionally, the enhanced influence of CPs and MPs on denitrification was expected to promote nitrate-dependent and sulfate-dependent anaerobic oxidation of methane, thereby resulting in less methane released into the environment. These findings shed light on the potential consequences of simultaneous exposure to CPs and MPs on biogeochemical nitrogen cycling in deep-sea cold seep sediments.
氯化石蜡（CPs）和微塑料（MPs）在深海冷泉沉积物中很常见，而氮循环过程经常发生在这些沉积物中。然而，人们对它们在这些环境中对沉积微生物群落和氮循环的联合影响知之甚少。本研究旨在通过微宇宙实验研究 CPs 和 MPs 对深海冷泉沉积物中微生物群落和氮循环的协同影响。我们的研究结果表明，CPs 和 MPs 的存在会显著改变微生物群落组成，促进海盐单胞菌的生长。此外，CPs 和 MPs 被发现增强了硝化、反硝化和厌氧氨氧化过程，这可以从硝化和反硝化相关基因的丰度增加以及 CPs 和 MPs 处理组中反硝化和厌氧氨氧化活性的增加得到证明，与对照组相比。此外，CPs 和 MPs 对反硝化的增强影响预计会促进硝酸盐依赖型和硫酸盐依赖型甲烷的厌氧氧化，从而减少甲烷释放到环境中。这些发现揭示了同时暴露于 CPs 和 MPs 对深海冷泉沉积物中生物地球化学氮循环的潜在影响。
