PDF(Pubmed)
Abstract：
The estuarine plastisphere, a novel ecological habitat in the Anthropocene, has garnered global concerns. Recent geochemical evidence has pointed out its potential role in influencing nitrogen biogeochemistry. However, the biogeochemical significance of the plastisphere and its mechanisms regulating nitrogen cycling remain elusive. Using 15N- and 13C-labelling coupled with metagenomics and metatranscriptomics, here we unveil that the plastisphere likely acts as an underappreciated nitrifying niche in estuarine ecosystems, exhibiting a 0.9 ~ 12-fold higher activity of bacteria-mediated nitrification compared to surrounding seawater and other biofilms (stone, wood and glass biofilms). The shift of active nitrifiers from O2-sensitive nitrifiers in the seawater to nitrifiers with versatile metabolisms in the plastisphere, combined with the potential interspecific cooperation of nitrifying substrate exchange observed among the plastisphere nitrifiers, collectively results in the unique nitrifying niche. Our findings highlight the plastisphere as an emerging nitrifying niche in estuarine environment, and deepen the mechanistic understanding of its contribution to marine biogeochemistry.
摘要：
河口质体，人类世的一个新颖的生态栖息地，引起了全球的关注。最近的地球化学证据指出了其在影响氮生物地球化学中的潜在作用。然而,质体的生物地球化学意义及其调节氮循环的机制仍然难以捉摸。使用15N和13C标记结合宏基因组学和超转录组学，在这里，我们揭示了质体可能是河口生态系统中被低估的硝化生态位，与周围的海水和其他生物膜相比，细菌介导的硝化活性高0.9〜12倍（石头，木材和玻璃生物膜)。活性硝化剂从海水中对O2敏感的硝化剂向质体中具有多种代谢的硝化剂的转变，结合在塑球硝化剂之间观察到的硝化底物交换的潜在种间合作，共同导致独特的硝化生态位。我们的发现强调了质体是河口环境中新兴的硝化生态位，并加深对其对海洋生物地球化学贡献的机械理解。
