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Thermal and geochemical influences on microbial biogeography in the hydrothermal sediments of G uaymas B asin, G ulf of C alifornia
Author(s) -
McKay Luke,
Klokman Vincent W.,
Mendlovitz Howard P.,
LaRowe Douglas E.,
Hoer Daniel R.,
Albert Daniel,
Amend Jan P.,
Teske Andreas
Publication year - 2016
Publication title -
environmental microbiology reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.229
H-Index - 69
ISSN - 1758-2229
DOI - 10.1111/1758-2229.12365
Subject(s) - archaea , hydrothermal vent , microbial population biology , methane , sediment , environmental chemistry , hydrothermal circulation , ecosystem , anaerobic oxidation of methane , thermophile , ecology , environmental science , chemistry , biology , bacteria , paleontology
Summary Extreme thermal gradients and compressed metabolic zones limit the depth range of microbial colonization in hydrothermally active sediments at G uaymas B asin. We investigated the physicochemical characteristics of this ecosystem and their influence on microbial community structure. Temperature‐related trends of δ 13 C values of methane and dissolved inorganic carbon from 36 sediment cores suggest in situ thermal limits for microbial anaerobic methane oxidation and organic carbon re‐mineralization near 80° C and 100° C respectively. Temperature logging probes deposited in hydrothermal sediments for 8 days demonstrate substantial thermal fluctuations of up to 25° C . Putative anaerobic methanotroph ( ANME ) populations dominate the archaeal community, transitioning from ANME ‐1 archaea in warm surficial sediments towards ANME ‐1 Guaymas archaea as temperatures increase downcore. Since ANME archaea performing anaerobic oxidation of methane double on longer time scales (months) compared with relatively rapid in situ temperature fluctuations (hours to days), we conclude that ANME archaea possess a high tolerance for short‐term shifts in the thermal regime.