Multifactorial effects of warming, low irradiance, and low salinity on Arctic kelps ...

• Main Authors: Lebrun, Anaïs, Miller, Cale A, Meynadier, Marc, Comeau, Steeve, Urrutti, Pierre, Alliouane, Samir, Schlegel, Robert, Gattuso, Jean-Pierre, Gazeau, Frédéric
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: PANGAEA 2024
• Subjects: Arctic; Climate change; kelps; mesocosm experiment; Mesocosm experiment; Arctic Biodiversity & Livelihoods FACE-IT; Arctic biodiversity; Ice; permafrost; Sea ice
• Online Access: https://dx.doi.org/10.1594/pangaea.971349; https://doi.pangaea.de/10.1594/PANGAEA.971349

The Arctic is projected to warm by 2 to 5°C by the end of the century. Warming causes melting of glaciers, shrinking of the areas covered by sea ice, and increased terrestrial runoff from snowfields and permafrost thawing. Warming, decreasing coastal underwater irradiance, and lower salinity are potentially threatening polar marine organisms, including kelps, that are key species of hard-bottom shallow communities. The present study investigates the physiological responses of four kelp species (Alaria esculenta, Laminaria digitata, Saccharina latissima, and Hedophyllum nigripes) to these environmental changes through a perturbation experiment in ex situ mesocosms. Kelps were exposed for six weeks to four experimental treatments: an unmanipulated control, a warming condition under the CO2 emission scenario SSP5-8.5, and two multifactorial conditions combining warming, low salinity, and low irradiance reproducing the future coastal Arctic exposed to terrestrial runoff under two CO2 emission scenarios (SSP2-4.5 ...