Print Email Facebook Twitter Abundance and Biogeochemical Impact of Cable Bacteria in Baltic Sea Sediments Title Abundance and Biogeochemical Impact of Cable Bacteria in Baltic Sea Sediments Author Hermans, Martijn (Universiteit Utrecht) Lenstra, Wytze K. (Universiteit Utrecht) Hidalgo-Martinez, Silvia (Universiteit Antwerpen) van Helmond, Niels A.G.M. (Universiteit Utrecht) Witbaard, Rob (Universiteit Utrecht) Meysman, F.J.R. (TU Delft BT/Environmental Biotechnology; Universiteit Antwerpen) Gonzalez, Santiago (NIOZ Royal Netherlands Institute for Sea Research) Slomp, Caroline P. (Universiteit Utrecht) Date 2019 Abstract Oxygen depletion in coastal waters may lead to release of toxic sulfide from sediments. Cable bacteria can limit sulfide release by promoting iron oxide formation in sediments. Currently, it is unknown how widespread this phenomenon is. Here, we assess the abundance, activity, and biogeochemical impact of cable bacteria at 12 Baltic Sea sites. Cable bacteria were mostly absent in sediments overlain by anoxic and sulfidic bottom waters, emphasizing their dependence on oxygen or nitrate as electron acceptors. At sites that were temporarily reoxygenated, cable bacterial densities were low. At seasonally hypoxic sites, cable bacterial densities correlated linearly with the supply of sulfide. The highest densities were observed at Gulf of Finland sites with high rates of sulfate reduction. Microelectrode profiles of sulfide, oxygen, and pH indicated low or no in situ cable bacteria activity at all sites. Reactivation occurred within 5 days upon incubation of an intact sediment core from the Gulf of Finland with aerated overlying water. We found no relationship between cable bacterial densities and macrofaunal abundances, salinity, or sediment organic carbon. Our geochemical data suggest that cable bacteria promote conversion of iron monosulfides to iron oxides in the Gulf of Finland in spring, possibly explaining why bottom waters in this highly eutrophic region rarely contain sulfide in summer. To reference this document use: http://resolver.tudelft.nl/uuid:8fd26ba7-572d-412c-aff2-796f04a80559 DOI https://doi.org/10.1021/acs.est.9b01665 ISSN 0013-936X Source Environmental Science & Technology (Washington), 53 (13), 7494-7503 Part of collection Institutional Repository Document type journal article Rights © 2019 Martijn Hermans, Wytze K. Lenstra, Silvia Hidalgo-Martinez, Niels A.G.M. van Helmond, Rob Witbaard, F.J.R. Meysman, Santiago Gonzalez, Caroline P. Slomp Files PDF acs.est.9b01665.pdf 2.22 MB Close viewer /islandora/object/uuid:8fd26ba7-572d-412c-aff2-796f04a80559/datastream/OBJ/view