caa a22 4500 467885966 CHVBK 20180406152734.0 cr unu---uuuuu 170328e20060801xx s 000 0 eng 10.1007/s10021-005-0057-y doi (NATIONALLICENCE)springer-10.1007/s10021-005-0057-y Exploration of a Submerged Sinkhole Ecosystem in Lake Huron [Elektronische Daten] [Bopaiah Biddanda, Dwight Coleman, Thomas Johengen, Steven Ruberg, Guy Meadows, Hans Van Sumeren, Richard Rediske, Scott Kendall] Dissolution of the Silurian-Devonian aquifer in the Lake Huron Basin has produced several karst formations in the bedrock (sinkholes), through which groundwater emerges onto the lake floor. During September 2003, we explored a recently discovered submerged sinkhole ecosystem (55 m × 40 m × ∼1 m) located at a depth of 93 m with a remotely operated vehicle (ROV) equipped with a conductivity-temperature-depth (CTD) system, an acoustic navigational system, a video camera, and a water sampling system. In addition to two morphotypes of benthic mats, a 1-2 m thick visibly cloudy near-bottom nepheloid-like layer (sinkhole plume) with a strong hydrogen sulfide odor prevailed just above the seepage area of clear water. Relative to lake water, water samples collected within the sinkhole plume were characterized by slightly higher (by 4°C) temperatures, very high levels of chloride (up to 175 mg l−1) and conductivity (1,700μS cm−1), as well as extremely high concentrations of sulfate (1,400 mg l−1), phosphorus (3 mg l−1) and particulate organic matter (400 mg C l−1). Compared to background lake water, sinkhole plume water was characterized by approximately twofold lower C:N ratios and tenfold higher levels of dissolved organic carbon, bacterial biomass as well as heterotrophic bacterial production. Significant uptake of 14C-bicarbonate in dark incubations provided preliminary evidence for occurrence of chemosynthesis, possibly mediated by specialized Bacteria and Archea present in this submerged sinkhole ecosystem in the Laurentian Great Lakes. Springer Science+Business Media, Inc., 2006 Laurentian Great Lakes Basin nationallicence submerged sinkholes nationallicence remotely operated vehicle nationallicence groundwater seep nationallicence nutrients nationallicence heterotrophic microbes nationallicence chemosynthesis nationallicence Lake Huron nationallicence Biddanda Bopaiah Annis Water Resources Institute and Lake Michigan Center, Grand Valley State University, 740 W Shoreline Drive, 49441, Muskegon, Michigan, USA aut Coleman Dwight Institute for Exploration, 55 Coogan Blvd., 06355, Mystic, Connecticut, USA aut Johengen Thomas Cooperative Institute for Limnology and Ecosystems Research, University of Michigan, 2205 Commonwealth Blvd., 48105, Ann Arbor, Michigan, USA aut Ruberg Steven National Oceanic and Atmospheric Administration, Great Lakes Environmental Research Laboratory, 2205 Commonwealth Blvd., 48105, Ann Arbor, Michigan, USA aut Meadows Guy Department of Naval Architecture & Marine Engineering, University of Michigan, 1085 South University Ave, 48109, Ann Arbor, Michigan, USA aut Van Sumeren Hans Department of Naval Architecture & Marine Engineering, University of Michigan, 1085 South University Ave, 48109, Ann Arbor, Michigan, USA aut Rediske Richard Annis Water Resources Institute and Lake Michigan Center, Grand Valley State University, 740 W Shoreline Drive, 49441, Muskegon, Michigan, USA aut Kendall Scott Annis Water Resources Institute and Lake Michigan Center, Grand Valley State University, 740 W Shoreline Drive, 49441, Muskegon, Michigan, USA aut Ecosystems Springer-Verlag; www.springer-ny.com 9/5(2006-08-01), 828-842 1432-9840 9:5<828 2006 9 10021 https://doi.org/10.1007/s10021-005-0057-y text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10021-005-0057-y text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Biddanda Bopaiah Annis Water Resources Institute and Lake Michigan Center, Grand Valley State University, 740 W Shoreline Drive, 49441, Muskegon, Michigan, USA aut NATIONALLICENCE 700 1- Coleman Dwight Institute for Exploration, 55 Coogan Blvd., 06355, Mystic, Connecticut, USA aut NATIONALLICENCE 700 1- Johengen Thomas Cooperative Institute for Limnology and Ecosystems Research, University of Michigan, 2205 Commonwealth Blvd., 48105, Ann Arbor, Michigan, USA aut NATIONALLICENCE 700 1- Ruberg Steven National Oceanic and Atmospheric Administration, Great Lakes Environmental Research Laboratory, 2205 Commonwealth Blvd., 48105, Ann Arbor, Michigan, USA aut NATIONALLICENCE 700 1- Meadows Guy Department of Naval Architecture & Marine Engineering, University of Michigan, 1085 South University Ave, 48109, Ann Arbor, Michigan, USA aut NATIONALLICENCE 700 1- Van Sumeren Hans Department of Naval Architecture & Marine Engineering, University of Michigan, 1085 South University Ave, 48109, Ann Arbor, Michigan, USA aut NATIONALLICENCE 700 1- Rediske Richard Annis Water Resources Institute and Lake Michigan Center, Grand Valley State University, 740 W Shoreline Drive, 49441, Muskegon, Michigan, USA aut NATIONALLICENCE 700 1- Kendall Scott Annis Water Resources Institute and Lake Michigan Center, Grand Valley State University, 740 W Shoreline Drive, 49441, Muskegon, Michigan, USA aut NATIONALLICENCE 773 0- Ecosystems Springer-Verlag; www.springer-ny.com 9/5(2006-08-01), 828-842 1432-9840 9:5<828 2006 9 10021 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer