@article {Bennett2015,
	title = {{Effect of depth and vent fluid composition on the carbon sources at two neighboring deep-sea hydrothermal vent fields (Mid-Cayman Rise)}},
	journal = {Deep-Sea Research Part I: Oceanographic Research Papers},
	volume = {104},
	year = {2015},
	pages = {122{\textendash}133},
	abstract = {In this study, we have used stable isotopes of megafauna, microbial mats and particulate organic matter to examine the effect of depth and vent fluid composition on the carbon sources at two proximal, chemically distinct hydrothermal vent fields along the Mid-Cayman Rise. The basalt hosted Piccard vent field (4980 m) is twice as deep as the ultramafic hosted Von Damm vent field (2300 m) and has very different faunal assemblages. Of particular note is the presence of seep-associated fauna, Escarpia and Lamellibrachia tubeworms, at the Von Damm vent field. We identify a greater range of carbon sources and a suggestion of increased photosynthetic inputs to the Von Damm vent field compared to Piccard vent field. Rimicaris hybisae shrimp are the only abundant species shared between the two vent fields with $δ$13C values ranging between -22.7 and -10.1{\textperthousand}. Higher concentrations of hydrogen sulfide in the vent fluids at Piccard is proposed to be responsible for varying the relative contributions of the carbon fixation cycles used by their epibionts. Seep-associated fauna at Von Damm rely on elevated, thermogenic hydrocarbon content of the vent fluids for their carbon source ($δ$13C values ranging from -21.3 to 11.6{\textperthousand}). They also derive energy from hydrogen sulfide formed by the microbial reduction of sulfide ($δ$34S values ranging from -10.2 to -6.9{\textperthousand}). The tubeworms have very short roots (buried at most a centimeter into rubble), suggesting that microbial sulfate reduction must be occurring either in the shallow subsurface and/or in the anterior part of the tube. Overall, megafauna at Von Damm vent field appear to have a smaller food chain length (smaller $δ$15N range) but a greater breadth of trophic resources compared to the megafauna at the Piccard vent field.},
	keywords = {ROV Jason (Remotely Operated Vehicle)},
	doi = {10.1016/j.dsr.2015.06.005},
	author = {Bennett, S A and Van Dover, C L and Breier, J A and Coleman, M L}
}
@article {ISI:000345820100015,
	title = {{A large volume particulate and water multi-sampler with in situ preservation for microbial and biogeochemical studies}},
	journal = {DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS},
	volume = {94},
	year = {2014},
	month = {dec},
	pages = {195{\textendash}206},
	type = {Article},
	abstract = {A new tool was developed for large volume sampling to facilitate marine microbiology and biogeochemical studies. It was developed for remotely operated vehicle and hydrocast deployments, and allows for rapid collection of multiple sample types from the water column and dynamic, variable environments such as rising hydrothermal plumes. It was used successfully during a cruise to the hydrothermal vent systems of the Mid-Cayman Rise. The Suspended Particulate Rosette V2 large volume multi-sampling system allows for the collection of 14 sample sets per deployment. Each sample set can include filtered material, whole (unfiltered) water, and filtrate. Suspended particulate can be collected on filters up to 142 mm in diameter and pore sizes down to 0.2 mu m. Filtration is typically at flowrates of 2 L min(-1) For particulate material, filtered volume is constrained only by sampling time and filter capacity, with all sample volumes recorded by digital flowmeter. The suspended particulate filter holders can be filled with preservative and sealed immediately after sample collection. Up to 2 L of whole water, filtrate, or a combination of the two, can be collected as part of each sample set. The system is constructed of plastics with titanium fasteners and nickel alloy spring loaded seals. There are no ferrous alloys in the sampling system. Individual sample lines are prefilled with filtered, deionized water prior to deployment and remain sealed unless a sample is actively being collected. This system is intended to facilitate studies concerning the relationship between marine microbiology and ocean biogeochemistry. (C) 2014 Elsevier Ltd. All rights reserved.},
	keywords = {ROV Jason (Remotely Operated Vehicle)},
	issn = {0967-0637},
	doi = {10.1016/j.dsr.2014.08.008},
	author = {Breier, J A and Sheik, C S and Gomez-Ibanez, D and Sayre-McCord, R T and Sanger, R and Rauch, C and Coleman, M and Bennett, S A and Cron, B R and Li, M and German, C R and Toner, B M and Dick, G J}
}
@article {Bennett2013,
	title = {{Trophic regions of a hydrothermal plume dispersing away from an ultramafic-hosted vent-system: Von Damm vent-site, Mid-Cayman Rise}},
	journal = {Geochemistry, Geophysics, Geosystems},
	volume = {14},
	number = {2},
	year = {2013},
	pages = {317{\textendash}327},
	abstract = {Deep-sea ultramafic-hosted vent systems have the potential to provide large amounts of metabolic energy to both autotrophic and heterotrophic microorganisms in their dispersing hydrothermal plumes. Such vent-systems release large quantities of hydrogen and methane to the water column, both of which can be exploited by autotrophic microorganisms. Carbon cycling in these hydrothermal plumes may, therefore, have an important influence on open-ocean biogeochemistry. In this study, we investigated an ultramafic-hosted system on the Mid-Cayman Rise, emitting metal-poor and hydrogen sulfide-, methane-, and hydrogen-rich hydrothermal fluids. Total organic carbon concentrations in the plume ranged between 42.1 and 51.1 $μ$M (background = 43.2 {\textpm} 0.7 $μ$M (n = 5)) and near-field plume samples with elevated methane concentrations imply the presence of chemoautotrophic primary production and in particular methanotrophy. In parts of the plume characterized by persistent potential temperature anomalies but lacking elevated methane concentrations, we found elevated organic carbon concentrations of up to 51.1 $μ$M, most likely resulting from the presence of heterotrophic communities, their extracellular products and vent larvae. Elevated carbon concentrations up to 47.4 $μ$M were detected even in far-field plume samples. Within the Von Damm hydrothermal plume, we have used our data to hypothesize a microbial food web in which chemoautotrophy supports a heterotrophic community of microorganisms. Such an active microbial food web would provide a source of labile organic carbon to the deep ocean that should be considered in any future studies evaluating sources and sinks of carbon from hydrothermal venting to the deep ocean.},
	keywords = {ROV Jason (Remotely Operated Vehicle)},
	issn = {1525-2027},
	doi = {10.1002/ggge.20063},
	url = {http://dx.doi.org/10.1002/ggge.20063},
	author = {Bennett, S A and Coleman, Max and Huber, J A and Reddington, E and Kinsey, J C and McIntyre, C and Seewald, J S and German, C R}
}
@article {Bennett2011,
	title = {{Dissolved and particulate organic carbon in hydrothermal plumes from the East Pacific Rise, 9 degrees 50'N}},
	journal = {Deep-Sea Research. Part I: Oceanographic Research Papers},
	volume = {58},
	number = {9},
	year = {2011},
	pages = {922{\textendash}931},
	abstract = {Chemoautotrophic production in seafloor hydrothermal systems has the potential to provide an important source of organic carbon that is exported to the surrounding deep-ocean. While hydrothermal plumes may export carbon, entrained from chimney walls and biologically rich diffuse flow areas, away from sites of venting they also have the potential to provide an environment for in-situ carbon fixation. In this study, we have followed the fate of dissolved and particulate organic carbon (DOC and POC) as it is dispersed through and settles beneath a hydrothermal plume system at 9{\textdegree}50'N on the East Pacific Rise. Concentrations of both DOC and POC are elevated in buoyant plume samples that were collected directly above sites of active venting using both DSV Alvin and a CTD-rosette. Similar levels of POC enrichment are also observed in the dispersing non-buoyant plume, \~{}500~m downstream from the vent-site. Further, sediment-trap samples collected beneath the same dispersing plume system, show evidence for a close coupling between organic carbon and Fe oxyhydroxide fluxes. We propose, therefore, a process that concentrates POC into hydrothermal plumes as they disperse through the deep-ocean. This is most probably the result of some combination of preferential adsorption of organic carbon onto Fe-oxyhydroxides and/or microbial activity that preferentially concentrates organic carbon in association with Fe-oxyhydroxides (e.g. through the microbial oxidation of Fe(II) and Fe sulfides). This potential for biological production and consumption within hydrothermal plumes highlights the importance of a multidisciplinary approach to understanding the role of the carbon cycle in deep-sea hydrothermal systems as well as the role that hydrothermal systems may play in regulating global deep-ocean carbon budgets.},
	keywords = {HOV Alvin (Human Occupied Vehicle)},
	issn = {0967-0637},
	doi = {10.1016/j.dsr.2011.06.010},
	url = {http://dx.doi.org/10.1016/j.dsr.2011.06.010},
	author = {Bennett, S A and Statham, P J and Green, D R H and Le Bris, N and McDermott, J M and Prado, F and Rouxel, O J and Von Damm, K L and German, C R}
}
@article {Bennett2011a,
	title = {{Tracing iron-fueled microbial carbon production within the hydrothermal plume at the Loihi Seamount}},
	journal = {Geochimica et Cosmochimica Acta},
	volume = {75},
	number = {19},
	year = {2011},
	pages = {5526{\textendash}5539},
	abstract = {The Loihi hydrothermal plume provides an opportunity to investigate iron (Fe) oxidation and microbial processes in a system that is truly Fe dominated and distinct from mid-ocean ridge spreading centers. The lack of hydrogen sulfide within the Loihi hydrothermal fluids and the presence of an oxygen minimum zone at this submarine volcano{\textquoteright}s summit, results in a prolonged presence of reduced Fe within the dispersing non-buoyant plume. In this study, we have investigated the potential for microbial carbon fixation within the Loihi plume. We sampled for both particulate and dissolved organic carbon in hydrothermal fluids, microbial mats growing around vents, and the dispersing plume, and carried out stable carbon isotope analysis on the particulate fraction. The $δ$13C values of the microbial mats ranged from -23{\textperthousand} to -28{\textperthousand}, and are distinct from those of deep-ocean particulate organic carbon (POC). The mats and hydrothermal fluids were also elevated in dissolved organic carbon (DOC) compared to background seawater. Within the hydrothermal plume, DOC and POC concentrations were elevated and the isotopic composition of POC within the plume suggests mixing between background seawater POC and a 13C-depleted hydrothermal component. The combination of both DOC and POC increasing in the dispersing plume that cannot solely be the result of entrainment and DOC adsorption, provides strong evidence for in-situ microbial productivity by chemolithoautotrophs, including a likelihood for iron-oxidizing microorganisms.},
	keywords = {ROV Jason (Remotely Operated Vehicle)},
	issn = {0016-7037},
	doi = {10.1016/j.gca.2011.06.039},
	url = {http://dx.doi.org/10.1016/j.gca.2011.06.039},
	author = {Bennett, S A and Hansman, R L and Sessions, A L and Nakamura, K and Edwards, K J}
}
