Integrated in-situ chemical sensor system for submersible deployment at deep-sea hydrothermal vents

OCEANS 2006 ◽  
2006 ◽  
Author(s):  
K. Ding ◽  
Z. Zhang ◽  
W. E. Seyfried ◽  
A. M. Bradley ◽  
Y. Zhou ◽  
...  
Keyword(s):  
Deep Sea ◽  
Hydrothermal Vents ◽  
Chemical Sensor ◽  
Sensor System

Pressure and Temperature Adaptation of Cytosolic Malate Dehydrogenases of Shallowand Deep-Living Marine Invertebrates: Evidence for High Body Temperatures in Hydrothermal Vent Animals

1991 ◽  
Vol 159 (1) ◽  
pp. 473-487 ◽  
Author(s):  
ELIZABETH DAHLHOFF ◽  
GEORGE N. SOMERO
Keyword(s):  
Deep Sea ◽  
Hydrothermal Vents ◽  
Elevated Temperatures ◽  
Marine Invertebrates ◽  
Distribution Patterns ◽  
Pressure Effects ◽  
Temperature Adaptation ◽  
Body Temperatures ◽  
Elevated Pressures

Effects of temperature and hydrostatic pressure were measured on cytosolic malate dehydrogenases (cMDHs) from muscle tissue of a variety of shallow- and deep-living benthic marine invertebrates, including seven species endemic to the deep-sea hydrothermal vents. The apparent Michaelis-Menten constant (Km) of coenzyme (nicotinamide adenine dinucleotide, NADH), used to index temperature and pressure effects, was conserved within a narrow range (approximately 15–25 μmoll−1) at physiological temperatures and pressures for all species. However, at elevated pressures, the Km of NADH rose sharply for cMDHs of shallow species (depths of occurrence >Approximately 500 m), but not for the cMDHs of deep-sea species. Cytosolic MDHs of invertebrates from the deep-sea hydrothermal vents generally were not perturbed by elevated temperatures (15–25°C) at in situ pressures, but cMDHs of cold-adapted deep-sea species were. At a single measurement temperature, the Km of NADH for cMDHs from invertebrates from habitats with well-characterized temperatures was inversely related to maximal sustained body temperature. This correlation was used to predict the maximal sustained body temperatures of vent invertebrates for which maximal habitat and body temperatures are difficult to estimate. Species occurring on the ‘smoker chimneys’, which emit waters with temperatures up to 380°C, are predicted to have sustained body temperatures that are approximately 20–25°C higher than vent species living in cooler vent microhabitats. We conclude that, just as adaptation of enzymes to elevated pressures is important in establishing species’ depth distribution patterns, adaptation of pressure-adapted enzymes to temperature is critical in enabling certain vent species to exploit warm-water microhabitats in the vent environment.

Comprehensive effects of oceanic pressure and temperature on in-situ LIBS signals

2021 ◽  
Author(s):  
Nan Li ◽  
Jinjia Guo ◽  
Jiaojian Song ◽  
Wangquan Ye ◽  
Yuan Lu ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Deep Sea ◽  
Chemical Sensor ◽  
Laser Induced Breakdown Spectroscopy ◽  
Breakdown Spectroscopy ◽  
Laser Induced Breakdown ◽  
Marine Environmental

Laser-induced breakdown spectroscopy (LIBS) has been successfully developed into the oceanic chemical sensor for deep-sea exploration. However, the LIBS signals will be affected by marine environmental factors, and this effect...

A Pressure-Tight Sampler with Flexible Titanium Bag for Deep-Sea Hydrothermal Fluid Samples

2020 ◽  
Vol 37 (11) ◽  
pp. 2065-2073
Author(s):  
Xun Wang ◽  
Shi-Jun Wu ◽  
Zhen-Fang Fang ◽  
Can-Jun Yang ◽  
Shuo Wang
Keyword(s):  
Organic Carbon ◽  
Deep Sea ◽  
Hydrothermal Vents ◽  
Hydrothermal Fluid ◽  
Titanium Foil ◽  
Fluid Sample ◽  
Sea Trial ◽  
Diaphragm Valve ◽  
Metal Seal

AbstractThis paper details the development and application of a novel pressure-tight sampler with a metal seal capable of acquiring high-purity fluid samples from deep-sea hydrothermal vents. The sampler has a titanium diaphragm valve for sampling and a flexible titanium foil bag to store the fluid sample. Hence, all parts of the sampler in contact with the sample are made of titanium without elastomer O-ring seals to minimize the organic carbon blank of the sampler, which makes it suitable for collecting organic samples. A pressure-tight structure was specially designed to maintain the sample at in situ pressure during the recovery of the sampler. The sampler has been successfully tested in a sea trial from November 2018 to March 2019, and pressure-tight hydrothermal fluid samples have been collected.

scholarly journals Group-Specific Carbon Fixation Activity Measurements Reveal Distinct Responses to Oxygen Among Hydrothermal vent Campylobacteria

2020 ◽  
Author(s):  
Jesse McNichol ◽  
Stefan Dyksma ◽  
Marc Mußmann ◽  
Jeffrey S. Seewald ◽  
Sean P. Sylva ◽  
...  
Keyword(s):  
Community Composition ◽  
Deep Sea ◽  
Hydrothermal Vent ◽  
Hydrothermal Vents ◽  
Carbon Fixation ◽  
Genomic Diversity ◽  
Sequence Variant ◽  
Activity Measurements ◽  
Initial Starting

AbstractMolecular surveys of low temperature deep-sea hydrothermal vent fluids have shown that Campylobacteria (prev. Epsilonproteobacteria) often dominate the microbial community and that three subgroups - Arcobacter, Sulfurimonas and Sulfurovum - frequently coexist. In this study, we used replicated radiocarbon incubations of deep-sea hydrothermal fluids to investigate the activities of each group under three distinct incubation conditions. In order to quantify group-specific radiocarbon incorporation, we used newly designed oligonucleotide probes for Arcobacter, Sulfurimonas, and Sulfurovum to quantify their activity using catalyzed-reporter deposition fluorescence in-situ hybridization (CARD-FISH) combined with fluorescence-activated cell sorting. All three groups actively fixed CO2 in short-term (~ 20 h) incubations with either nitrate, oxygen, or no additions (control) at similar per-cell carbon fixation rates. Oxygen additions had the largest effect on community composition and overall cell numbers, and caused a pronounced shift in community composition at the amplicon sequence variant (ASV) level after only 20 h of incubation for all three groups. Interestingly, the effect of oxygen on carbon fixation rates appeared to depend on the initial starting community. Higher carbon fixation rates in oxygen-amended treatments were noted for all three taxa after an unintended disturbance to the sample site that may have selected for more oxygen-tolerant phylotypes. When viewed from a coarse taxonomic level, our data support assertions that these chemoautotrophic groups are functionally redundant in terms of their core metabolic capabilities since they were simultaneously active under all incubation conditions. In contrast, the higher resolution of amplicon sequencing allowed us to reveal finer-scale differences in growth that likely reflect adaptation of physiologically-distinct subtypes to varying oxygen concentrations in situ. Despite this progress, we still know remarkably little about the factors that maintain genomic diversity and allow for stable co-existence among these three campylobacterial groups. Moving forward, we suggest that more subtle biological factors such as enzyme substrate specificity, motility, cell morphology, and tolerance to environmental stress should be more thoroughly investigated to better understand ecological niche differentiation at deep-sea hydrothermal vents.

In Situ Voltammetry at Deep-Sea Hydrothermal Vents

2002 ◽  
pp. 40-51 ◽  
Author(s):  
Donald B. Nuzzio ◽  
Martial Taillefert ◽  
S. Craig Cary ◽  
Anna Louise Reysenbach ◽  
George W. Luther
Keyword(s):  
Deep Sea ◽  
Hydrothermal Vents

scholarly journals Rapid Microbial Production of Filamentous Sulfur Mats at Hydrothermal Vents

1999 ◽  
Vol 65 (5) ◽  
pp. 2253-2255 ◽  
Author(s):  
Craig D. Taylor ◽  
Carl O. Wirsen ◽  
Françoise Gaill
Keyword(s):  
Deep Sea ◽  
Hydrothermal Vent ◽  
Continuous Flow ◽  
Hydrothermal Vents ◽  
Flow Reactors ◽  
Organic Matter Production ◽  
Matter Production ◽  
Metabolic Capability ◽  
Continuous Flow Reactors

ABSTRACT During recent oceanographic cruises to Pacific hydrothermal vent sites (9°N and the Guaymas Basin), the rapid microbial formation of filamentous sulfur mats by a new chemoautotrophic, hydrogen sulfide-oxidizing bacterium was documented in both in situ and shipboard experiments. Observations suggest that formation of these sulfur mats may be a factor in the initial colonization of hydrothermal surfaces by macrofaunal Alvinella worms. This novel metabolic capability, previously shown to be carried out by a coastal strain in H2S continuous-flow reactors, may be an important, heretofore unconsidered, source of microbial organic matter production at deep-sea hydrothermal vents.

New IR Fiber-Optic Chemical Sensor for in Situ Measurements of Chlorinated Hydrocarbons in Water

1993 ◽  
Vol 47 (9) ◽  
pp. 1484-1487 ◽  
Author(s):  
R. Krska ◽  
K. Taga ◽  
R. Kellner
Keyword(s):  
Evanescent Wave ◽  
Chemical Sensor ◽  
Fiber Optic ◽  
Silver Halide ◽  
Chlorinated Hydrocarbons ◽  
Sensor System ◽  
Absorption Bands ◽  
Relative Standard ◽  
Polycrystalline Silver

In this work the development and validation of a new MIR fiber-optic physicochemical sensor system for the continuous in situ analysis of chlorinated hydrocarbons (CHCs) in water is described. This study took advantage of the selectivity and sensitivity of fiber evanescent wave spectroscopy (FEWS) and the recent development of polycrystalline silver halide fibers. Since these fibers are transparent up to 20 μm, it was possible for the first time to develop a fiber-optic sensing system for CHCs, which have their strongest absorption bands > 10 μm. The silver halide fibers were coated with low-density polyethylene (LDPE) to enrich the CHC within the evanescent wave and to exclude the IR absorbing water from the measurement. For the quantitative in situ FEWS measurements, the coated silver halide fibers were coupled to a Fourier transform infrared (FT-IR) spectrometer using an off-axis parabolic mirror and a fiber-detector coupling system. This setup enabled the simultaneous in situ detection of the most common chlorinated hydrocarbons in concentrations between 1 to 50 mg/L in water by employing a fiber sensing part only 10 cm in length. A comparative analysis of waste water samples under participation of two experienced head space-gas chromatography (HSGC) laboratories showed good agreement of this continuous sensor system with the established standard techniques. The resulting working curve for tetrachloroethylene showed a correlation coefficient of r2 = 0.968 and a relative standard deviation of 17% in the range from 1 to 10 ppm.

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