School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou, 510006, P. R. China.
Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, P. R. China.
Adv Sci (Weinh). 2023 Apr;10(10):e2206120. doi: 10.1002/advs.202206120. Epub 2023 Feb 3.
Microplastic (MP) pollution is one of the greatest threats to marine ecosystems. Cold seeps are characterized by methane-rich fluid seepage fueling one of the richest ecosystems on the seafloor, and there are approximately more than 900 cold seeps globally. While the long-term evolution of MPs in cold seeps remains unclear. Here, how MPs have been deposited in the Haima cold seep since the invention of plastics is demonstrated. It is found that the burial rates of MPs in the non-seepage areas significantly increased since the massive global use of plastics in the 1930s, nevertheless, the burial rates and abundance of MPs in the methane seepage areas are much lower than the non-seepage area of the cold seep, suggesting the degradation potential of MPs in cold seeps. More MP-degrading microorganism populations and functional genes are discovered in methane seepage areas to support this discovery. It is further investigated that the upwelling fluid seepage facilitated the fragmentation and degradation behaviors of MPs. Risk assessment indicated that long-term transport and transformation of MPs in the deeper sediments can reduce the potential environmental and ecological risks. The findings illuminated the need to determine fundamental strategies for sustainable marine plastic pollution mitigation in the natural deep-sea environments.
微塑料（MP）污染是对海洋生态系统的最大威胁之一。冷泉以富含甲烷的流体渗漏为特征，是海底最富饶的生态系统之一，全球大约有 900 多个冷泉。尽管冷泉中 MPs 的长期演化仍不清楚。在这里，展示了自塑料发明以来，MP 是如何在海马冷泉中沉积的。研究发现，自 20 世纪 30 年代塑料的大规模全球使用以来，非渗漏区 MPs 的埋藏率显著增加，然而，渗漏区和非渗漏区甲烷渗漏区 MPs 的埋藏率和丰度要低得多，这表明冷泉中 MPs 具有降解潜力。在甲烷渗漏区发现了更多的 MP 降解微生物种群和功能基因，以支持这一发现。进一步研究表明，上升流流体渗漏促进了 MPs 的碎裂和降解行为。风险评估表明， MPs 在更深沉积物中的长期输运和转化可以降低潜在的环境和生态风险。这些发现阐明了在自然深海环境中确定可持续海洋塑料污染缓解的基本策略的必要性。
