Abstract：
To date, multiple studies have shown that the accumulation of microplastics (MPs)/nanoplastics (NPs) in the environment may lead to various problems. However, the effects of MPs/NPs on microbial communities and biogeochemical processes, particularly methane metabolism in cold seep sediments, have not been well elucidated. In this study, an indoor microcosm experiment for a period of 120 days exposure of MPs/NPs was conducted. The results showed that MPs/NPs addition did not significantly influence bacterial and archaeal richness in comparison with the control (p > 0.05), whereas higher levels of NPs (1 %, w/w) had a significant adverse effect on bacterial diversity (p < 0.05). Moreover, the bacterial community was more sensitive to the addition of MPs/NPs than the archaea, and Epsilonbacteraeota replaced Proteobacteria as the dominant phylum in the MPs/NPs treatments (except 0.2 % NPs). With respect to the co-occurrence relationships, network analysis showed that the presence of NPs, in comparison with MPs, reduced microbial network complexity. Finally, the presence of MPs/NPs decreased the abundance of mcrA, while promoting the abundance of pmoA. This study will help elucidate the responses of microbial communities to MPs/NPs and evaluate their effects on methane metabolism in cold seep ecosystems.
摘要：
迄今为止,多项研究表明，微塑料（MPs）/纳米塑料（NPs）在环境中的积累可能导致各种问题。然而,MPs/NPs对微生物群落和生物地球化学过程的影响，特别是在冷渗漏沉积物中的甲烷代谢，还没有很好地阐明。在这项研究中,进行了为期120天的MP/NP暴露的室内微观实验。结果表明，与对照相比，MPs/NPs的添加对细菌和古细菌的丰富度没有显着影响（p>0.05）。而NPs水平较高(1%，w/w)对细菌多样性有显著的不良影响(p<0.05)。此外，细菌群落对MPs/NPs的添加比古细菌更敏感，在MPs/NPs处理中（0.2%NPs除外），并取代了变形杆菌作为优势门。关于共现关系，网络分析显示，NPs的存在，与国会议员相比，降低微生物网络的复杂性。最后,MPs/NPs的存在降低了MCRA的丰度，同时促进了pmoA的丰富。这项研究将有助于阐明微生物群落对MPs/NPs的反应，并评估其对冷渗漏生态系统中甲烷代谢的影响。
