Influence of Water Masses on the Biodiversity and Biogeography of Deep-Sea Benthic Ecosystems in the North Atlantic

• Published in: Frontiers in Marine Science
• Main Authors: Manuel Gonzalez-Irusta, Jose, Arnaud-Haond, Sophie, Orejas, Covadonga, Puerta, Patricia, Johnson, Clare, Carreiro-Silva, Marina, Henry, Lea-Anne, Kenchington, Ellen, Morato, Telmo, Kazanidis, Georgios, Luis Rueda, Jose, Urra, Javier, Ross, Steve, Wei, Chih-Lin
• Other Authors: MARine Biodiversity Exploitation and Conservation (UMR MARBEC), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut de Recherche pour le Développement (IRD), Instituto Español de Oceanografía (IEO), Málaga., Instituto do Mar - Universidade dos Açores (IMAR-UAc), University of Edinburgh, Fisheries and Oceans Canada (DFO), Marine and Environmental Sciences Centre Portugal (MARE), Instituto Universitário de Ciências Psicológicas, Sociais e da Vida (ISPA), University of North Carolina Wilmington (UNC), University of North Carolina System (UNC)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2020
• Subjects: water masses; rockall trough margin; biodiversity; North Atlantic; ocean acidification; biogeography; deep-sea; vulnerable marine ecosystems; antarctic intermediate water; climate-change impacts; coral lophelia-pertusa; food-supply mechanisms; global habitat suitability; meridional overturning circulation; ne atlantic; porcupine seabight; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; [SDE.MCG]Environmental Sciences/Global Changes; Antarctic; Porcupine Seabight; Rockall Trough; Antarc*; Lophelia pertusa; Ocean acidification
• Online Access: https://hal.umontpellier.fr/hal-03411053; https://hal.umontpellier.fr/hal-03411053/document; https://hal.umontpellier.fr/hal-03411053/file/fmars-07-00239.pdf; https://doi.org/10.3389/fmars.2020.00239

Place: Lausanne Publisher: Frontiers Media Sa WOS:000526864100001 International audience Circulation patterns in the North Atlantic Ocean have changed and re-organized multiple times over millions of years, influencing the biodiversity, distribution, and connectivity patterns of deep-sea species and ecosystems. In this study, we review the effects of the water mass properties (temperature, salinity, food supply, carbonate chemistry, and oxygen) on deep-sea benthic megafauna (from species to community level) and discussed in future scenarios of climate change. We focus on the key oceanic controls on deep-sea megafauna biodiversity and biogeography patterns. We place particular attention on cold-water corals and sponges, as these are ecosystem-engineering organisms that constitute vulnerable marine ecosystems (VME) with high associated biodiversity. Besides documenting the current state of the knowledge on this topic, a future scenario for water mass properties in the deep North Atlantic basin was predicted. The pace and severity of climate change in the deep-sea will vary across regions. However, predicted water mass properties showed that all regions in the North Atlantic will be exposed to multiple stressors by 2100, experiencing at least one critical change in water temperature (+2 degrees C), organic carbon fluxes (reduced up to 50%), ocean acidification (pH reduced up to 0.3), aragonite saturation horizon (shoaling above 1000 m) and/or reduction in dissolved oxygen (\textgreater 5%). The northernmost regions of the North Atlantic will suffer the greatest impacts. Warmer and more acidic oceans will drastically reduce the suitable habitat for ecosystem-engineers, with severe consequences such as declines in population densities, even compromising their long-term survival, loss of biodiversity and reduced biogeographic distribution that might compromise connectivity at large scales. These effects can be aggravated by reductions in carbon fluxes, particularly in areas where food availability is already ...