Graduate school of Natural Science and Technology, Okayama University, Kita-ku, Okayama, Okayama, Japan.
Department of Subsurface Geobiological Analysis and Research (D-SUGAR), Japan Agency for Marine-Earth Science and Technology, Yokosuka, Kanagawa, Japan.
PLoS One. 2018 Jun 15;13(6):e0199000. doi: 10.1371/journal.pone.0199000. eCollection 2018.
The Shinkai Seep Field (SSF) in the southern Mariana forearc discovered in 2010 is the deepest (5,700 m in depth) known serpentinite-hosted ecosystem dominated by a vesicomyid clam, Calyptogena (Abyssogena) mariana. The pioneering study presumed that the animal communities are primary sustained by reducing fluid originated from the serpentinization of mantle peridotite. For understanding the nutrient and energy sources for the SSF community, this study conducted four expeditions to the SSF and collected additional animal samples such as polychaetes and crustaceans as well as sediments, fragments of chimneys developing on fissures of serpentinized peridotite, seeping fluid on the chimneys, and pore water within the chimneys. Geochemical analyses of seeping fluids on the chimneys and pore water of the chimneys revealed significantly high pH (10) that suggest subseafloor serpentinization controlling fluid chemistry. Stable isotope systematics (carbon, nitrogen, and sulfur) among animals, inorganic molecules, and environmental organic matter suggest that the SSF animal community mostly relies on the chemosynthetic production while some organisms appear to partly benefit from photosynthetic production despite the great depth of SSF.
2010 年在马里亚纳弧前区发现的深海泉（Shinkai Seep Field，SSF）是已知的最深的蛇纹岩为主的生态系统（深度约 5700 米），其中主要由一种 vesicomyid 蛤类——Calyptogena（Abyssogena）mariana 占据。这项开创性的研究假设，动物群落主要由地幔橄榄岩蛇纹石化产生的还原流体维持。为了了解 SSF 群落的营养和能量来源，本研究进行了四次 SSF 考察，并收集了额外的动物样本，如多毛类和甲壳类动物以及沉积物、发育在蛇纹石化橄榄岩裂隙上的烟囱碎片、烟囱上渗出的流体以及烟囱内的孔隙水。对烟囱上渗出的流体和烟囱内孔隙水的地球化学分析表明，pH 值显著较高（约 10），表明地下蛇纹石化控制着流体化学。动物、无机分子和环境有机质之间的稳定同位素系统（碳、氮和硫）表明，SSF 动物群落主要依赖于化能合成生产，而尽管 SSF 深度很大，但一些生物似乎部分受益于光合作用生产。
