scholarly journals Effect of explosive shallow hydrothermal vents on δ13C and growth performance in the seagrass Posidonia oceanica

2010 ◽  
Vol 98 (6) ◽  
pp. 1284-1291 ◽  
Author(s):  
Salvatrice Vizzini ◽  
Agostino Tomasello ◽  
Germana Di Maida ◽  
Maria Pirrotta ◽  
Antonio Mazzola ◽  
...  
Keyword(s):  
Growth Performance ◽  
Hydrothermal Vents ◽  
Posidonia Oceanica ◽  
Shallow Hydrothermal Vents

Bacterial and archaeal populations at two shallow hydrothermal vents off Panarea Island (Eolian Islands, Italy)

Extremophiles ◽  
2008 ◽  
Vol 13 (1) ◽  
pp. 199-212 ◽  
Author(s):  
Teresa Luciana Maugeri ◽  
Valeria Lentini ◽  
Concetta Gugliandolo ◽  
Francesco Italiano ◽  
Sylvie Cousin ◽  
...  
Keyword(s):  
Hydrothermal Vents ◽  
Shallow Hydrothermal Vents

scholarly journals Earthquake and typhoon trigger unprecedented transient shifts in shallow hydrothermal vents biogeochemistry

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Mario Lebrato ◽  
Yiming V. Wang ◽  
Li-Chun Tseng ◽  
Eric P. Achterberg ◽  
Xue-Gang Chen ◽  
...  
Keyword(s):  
Hydrothermal Vents ◽  
Dissolved Inorganic Carbon ◽  
Total Alkalinity ◽  
Carbonate System ◽  
Sr:Ca Ratios ◽  
Dissolved Heavy Metals ◽  
One Year ◽  
High Level ◽  
Shallow Hydrothermal Vents ◽  
Surrounding Seawater

AbstractShallow hydrothermal vents are of pivotal relevance for ocean biogeochemical cycles, including seawater dissolved heavy metals and trace elements as well as the carbonate system balance. The Kueishan Tao (KST) stratovolcano off Taiwan is associated with numerous hydrothermal vents emitting warm sulfur-rich fluids at so-called White Vents (WV) and Yellow Vent (YV) that impact the surrounding seawater masses and habitats. The morphological and biogeochemical consequences caused by a M5.8 earthquake and a C5 typhoon (“Nepartak”) hitting KST (12th May, and 2nd–10th July, 2016) were studied within a 10-year time series (2009–2018) combining aerial drone imagery, technical diving, and hydrographic surveys. The catastrophic disturbances triggered landslides that reshaped the shoreline, burying the seabed and, as a consequence, native sulfur accretions that were abundant on the seafloor disappeared. A significant reduction in venting activity and fluid flow was observed at the high-temperature YV. Dissolved Inorganic Carbon (DIC) maxima in surrounding seawater reached 3000–5000 µmol kg−1, and Total Alkalinity (TA) drawdowns were below 1500–1000 µmol kg−1 lasting for one year. A strong decrease and, in some cases, depletion of dissolved elements (Cd, Ba, Tl, Pb, Fe, Cu, As) including Mg and Cl in seawater from shallow depths to the open ocean followed the disturbance, with a recovery of Mg and Cl to pre-disturbance concentrations in 2018. The WV and YV benthic megafauna exhibited mixed responses in their skeleton Mg:Ca and Sr:Ca ratios, not always following directions of seawater chemical changes. Over 70% of the organisms increased skeleton Mg:Ca ratio during rising DIC (higher CO2) despite decreasing seawater Mg:Ca ratios showing a high level of resilience. KST benthic organisms have historically co-existed with such events providing them ecological advantages under extreme conditions. The sudden and catastrophic changes observed at the KST site profoundly reshaped biogeochemical processes in shallow and offshore waters for one year, but they remained transient in nature, with a possible recovery of the system within two years.

scholarly journals A Special Issue on Microorganisms from Extreme Environments in Memory of Luigi Michaud (1974–2014)

Diversity ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 2
Author(s):  
Angelina Lo Giudice ◽  
Concetta Gugliandolo
Keyword(s):  
Microbial Diversity ◽  
Hydrothermal Vents ◽  
Extreme Environments ◽  
Research Paper ◽  
Special Issue ◽  
Research Papers ◽  
Biotechnological Potential ◽  
Geothermal Soils ◽  
Extremophilic Microorganisms ◽  
Shallow Hydrothermal Vents

A special issue (SI) titled “Microbial Diversity in Extreme Environments: Implications for Ecological and Applicative Perspectives” has been launched with the aim of showcasing the diversity and biotechnological potential of extremophilic microorganisms. The issue includes 10 research papers and four reviews that mainly address prokaryotes inhabiting hyperarid, hypercold, hyperalkaline and hypersaline (or polyextreme) environments, spanning from deserts to meromictic and glacier lakes around the globe. Thermophilic prokaryotes from shallow hydrothermal vents and Antarctic geothermal soils are also treated. The ecology and biotechnological perspectives of eukaryotes are discussed in two review papers and one research paper. This special issue serves as a memorial to Dr. Luigi Michaud (1974–2014), who dramatically passed away in Antarctica during underwater sampling activities.

scholarly journals A Handheld Sampler for Collecting Organic Samples from Shallow Hydrothermal Vents

2013 ◽  
Vol 30 (8) ◽  
pp. 1951-1958 ◽  
Author(s):  
Shi-Jun Wu ◽  
Can-Jun Yang ◽  
Chen-Tung Arthur Chen
Keyword(s):  
Hydrothermal Vents ◽  
Ambient Pressure ◽  
Machining Accuracy ◽  
Regulation Mechanism ◽  
Filling Rate ◽  
Compact Structure ◽  
Scuba Divers ◽  
Annular Gap ◽  
Gas Tight ◽  
Shallow Hydrothermal Vents

Abstract This study describes a new handheld sampler, specially designed to be deployed by scuba divers, to collect fluid samples from shallow hydrothermal vents. The new sampler utilizes a syringe-like titanium sampling bottle with a regulated filling rate to collect samples. The filling rate regulation mechanism of the new sampler was studied. Through theoretical analysis and simulation, it is found that the filling rate can be regulated by either an orifice or an annular gap on the sampler. Further study indicates that the orifice is superior to the annular gap, since the former has a much lower requirement of machining accuracy. Moreover, the filling rate regulated by the orifice is independent of temperature and ambient pressure. The new sampler also features a compact structure, simple operation, and gas-tight performance. Efforts were made to minimize the organic carbon blank of the sampler by careful selection of the materials that may come into contact with the fluid samples. The sampler has been tested at the shallow hydrothermal vents off northeastern Taiwan. High-purity organic samples were successfully collected.

scholarly journals Novel, Attached, Sulfur-Oxidizing Bacteria at Shallow Hydrothermal Vents Possess Vacuoles Not Involved in Respiratory Nitrate Accumulation

2004 ◽  
Vol 70 (12) ◽  
pp. 7487-7496 ◽  
Author(s):  
Karen M. Kalanetra ◽  
Sherry L. Huston ◽  
Douglas C. Nelson
Keyword(s):  
Hydrothermal Vents ◽  
Repeated Measurements ◽  
Rrna Gene ◽  
Nitrate Accumulation ◽  
Sulfur Bacteria ◽  
Physiological Properties ◽  
Large Central Vacuole ◽  
White Point ◽  
Sulfur Oxidizing ◽  
Shallow Hydrothermal Vents

ABSTRACT Novel, vacuolate sulfur bacteria occur at shallow hydrothermal vents near White Point, Calif. There, these filaments are attached densely to diverse biotic and abiotic substrates and extend one to several centimeters into the surrounding environment, where they are alternately exposed to sulfidic and oxygenated seawater. Characterizations of native filaments collected from this location indicate that these filaments possess novel morphological and physiological properties compared to all other vacuolate bacteria characterized to date. Attached filaments, ranging in diameter from 4 to 100 μm or more, were composed of cylindrical cells, each containing a thin annulus of sulfur globule-filled cytoplasm surrounding a large central vacuole. A near-complete 16S rRNA gene sequence was obtained and confirmed by fluorescent in situ hybridization to be associated only with filaments having a diameter of 10 μm or more. Phylogenetic analysis indicates that these wider, attached filaments form within the gamma proteobacteria a monophyletic group that includes all previously described vacuolate sulfur bacteria (the genera Beggiatoa, Thioploca, and Thiomargarita) and no nonvacuolate genera. However, unlike for all previously described vacuolate bacteria, repeated measurements of cell lysates from samples collected over 2 years indicate that the attached White Point filaments do not store internal nitrate. It is possible that these vacuoles are involved in transient storage of oxygen or contribute to the relative buoyancy of these filaments.

Shoot age as a confounding factor on detecting the effect of human-induced disturbance on Posidonia oceanica growth performance

2007 ◽  
Vol 343 (2) ◽  
pp. 166-175 ◽  
Author(s):  
Agostino Tomasello ◽  
Sebastiano Calvo ◽  
Germana Di Maida ◽  
Gianfranco Lovison ◽  
Maria Pirrotta ◽  
...  
Keyword(s):  
Growth Performance ◽  
Confounding Factor ◽  
Posidonia Oceanica
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