Contrasting responses to salinity and future ocean acidification in arctic populations of the amphipod Gammarus setosus.

• Published in: Marine Environmental Research
• Main Authors: Brown, James, Whiteley, Nia M, Bailey, Allison M, Graham, Helen, Hop, Haakon, Rastrick, Samuel P S
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2020
• Subjects: Amphipods; Arctic; Cellular energy budgets; Kongsfjorden; Metabolic rates; Ocean acidification; Salinity; Svalbard; Krossfjorden; Climate change; Kongsfjord*; Krossfjord*; Subarctic
• Online Access: http://hdl.handle.net/10034/623938; https://doi.org/10.1016/j.marenvres.2020.105176

From PubMed via Jisc Publications Router History: received 2020-06-12, revised 2020-09-10, accepted 2020-10-06 Publication status: aheadofprint Climate change is leading to alterations in salinity and carbonate chemistry in arctic/sub-arctic marine ecosystems. We examined three nominal populations of the circumpolar arctic/subarctic amphipod, Gammarus setosus, along a salinity gradient in the Kongsfjorden-Krossfjorden area of Svalbard. Field and laboratory experiments assessed physiological (haemolymph osmolality and gill Na /K -ATPase activity, NKA) and energetic responses (metabolic rates, MO , and Cellular Energy Allocation, CEA). In the field, all populations had similar osmregulatory capacities and MO , but lower-salinity populations had lower CEA. Reduced salinity (S = 23) and elevated pCO (~1000 μatm) in the laboratory for one month increased gill NKA activities and reduced CEA in all populations, but increased MO in the higher-salinity population. Elevated pCO did not interact with salinity and had no effect on NKA activities or CEA, but reduced MO in all populations. Reduced CEA in lower-rather than higher-salinity populations may have longer term effects on other energy demanding processes (growth and reproduction). [Abstract copyright: Copyright © 2020 Elsevier Ltd. All rights reserved.]