德国不来梅大学Kai-Uwe Hinrichs团队发现，温度限制了南开海槽俯冲带深层海底生物的生存。这一研究成果发表在2020年12月4日出版的国际学术期刊《科学》上。
研究人员调查了南开海槽俯冲带中1.2公里深和120°C高温沉积物中微生物的寿命。在高于45°C的环境中，营养细胞的浓度下降了两个数量级，并且内生孢子的富集度比营养细胞高6000倍。甲烷是由生物活动产生，直到沉积物达到80°至85°C时才会被氧化。 在100°至120°C的沉积物中，同位素和细胞浓度增加证明了可降解乙酸盐超嗜热菌的活性。在高于45°C的地带，生物量稠密区域与无法检测到微生物的192米深区域交替出现。
据了解，海洋地下沉积物中的微生物极大地促进了全球生物量。高于40°C的沉积物约占海洋沉积物总量的一半，但在这些难以接近的环境中，由微生物种群介导的过程知之甚少。
附：英文原文
Title: Temperature limits to deep subseafloor life in the Nankai Trough subduction zone
Author: Verena B. Heuer, Fumio Inagaki, Yuki Morono, Yusuke Kubo, Arthur J. Spivack, Bernhard Viehweger, Tina Treude, Felix Beulig, Florence Schubotz, Satoshi Tonai, Stephen A. Bowden, Margaret Cramm, Susann Henkel, Takehiro Hirose, Kira Homola, Tatsuhiko Hoshino, Akira Ijiri, Hiroyuki Imachi, Nana Kamiya, Masanori Kaneko, Lorenzo Lagostina, Hayley Manners, Harry-Luke McClelland, Kyle Metcalfe, Natsumi Okutsu, Donald Pan, Maija J. Raudsepp, Justine Sauvage, Man-Yin Tsang, David T. Wang, Emily Whitaker, Yuzuru Yamamoto, Kiho Yang, Lena Maeda, Rishi R. Adhikari, Clemens Glombitza, Yohei Hamada, Jens Kallmeyer, Jenny Wendt, Lars Wrmer, Yasuhiro Yamada, Masataka Kinoshita, Kai-Uwe Hinrichs
Issue&Volume: 2020/12/04
Abstract: Microorganisms in marine subsurface sediments substantially contribute to global biomass. Sediments warmer than 40°C account for roughly half the marine sediment volume, but the processes mediated by microbial populations in these hard-to-access environments are poorly understood. We investigated microbial life in up to 1.2-kilometer-deep and up to 120°C hot sediments in the Nankai Trough subduction zone. Above 45°C, concentrations of vegetative cells drop two orders of magnitude and endospores become more than 6000 times more abundant than vegetative cells. Methane is biologically produced and oxidized until sediments reach 80° to 85°C. In 100° to 120°C sediments, isotopic evidence and increased cell concentrations demonstrate the activity of acetate-degrading hyperthermophiles. Above 45°C, populated zones alternate with zones up to 192 meters thick where microbes were undetectable.
DOI: 10.1126/science.abd7934
Source: https://science.sciencemag.org/content/370/6521/1230