Earthquake and typhoon trigger unprecedented transient shifts in shallow hydrothermal vents biogeochemistry
|Author(s)||Lebrato Mario1, 2, Wang Yiming V.1, 3, Tseng Li-Chun4, Achterberg Eric P.5, Chen Xue-Gang6, Molinero Juan-Carlos1, 7, Bremer Karen1, Westernstroeer Ulrike1, Soeding Emanuel1, Dahms Hans-Uwe8, Kueter Marie1, Heinath Verena1, Joehnck Janika1, Konstantinou Kostas I.9, Yang Yiing J.10, Hwang Jiang-Shiou4, Garbe-Schoenberg Dieter1, 11|
|Affiliation(s)||1 : Kiel Univ CAU, Inst Geosci, Kiel, Germany.
2 : BCSS, Benguerra Isl, Mozambique.
3 : Max Planck Inst Sci Human Hist, Jena, Germany.
4 : Natl Taiwan Ocean Univ, Keelung, Taiwan.
5 : GEOMAR Helmholtz Ctr Ocean Res Kiel, Kiel, Germany.
6 : Zhejiang Univ, Ocean Coll, Zhoushan City, Peoples R China.
7 : Univ Montpellier, Marine Biodivers Exploitat & Conservat MARBEC, CNRS, IRD,IFREMER, Montpellier, France.
8 : Kaohsiung Med Univ, Kaohsiung, Taiwan.
9 : Natl Cent Univ, Taoyuan, Taiwan.
10 : Natl Taiwan Univ, Taipei, Taiwan.
11 : Jacobs Univ Bremen gGmbH, Bremen, Germany.
|Source||Scientific Reports (2045-2322) (Nature Publishing Group), 2019-11 , Vol. 9 , N. 16926 , P. 14p.|
|WOS© Times Cited||4|
|Abstract||Shallow 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-temperatureYV. Dissolved Inorganic Carbon (DIC) maxima in surrounding seawater reached 3000-5000 mu mol kg(-1), and Total Alkalinity (TA) drawdowns were below 1500-1000 mu mol 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.|