Effects of Ocean Acidification and Summer Thermal Stress on the Physiology and Growth of the Atlantic Surfclam ( Spisula solidissima )

This study examines the physiological response of the Atlantic surfclam ( Spisula solidissima ) to ocean acidification in warm summer temperatures. Working with ambient seawater, this experiment manipulated pH conditions while maintaining natural diel fluctuations and seasonal shifts in temperature....

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Bibliographic Details
Published in:Journal of Marine Science and Engineering
Main Authors: Laura Steeves, Molly Honecker, Shannon L. Meseck, Daphne Munroe
Format: Article in Journal/Newspaper
Language:English
Published: MDPI AG 2024
Subjects:
pH
Online Access:https://doi.org/10.3390/jmse12040673
https://doaj.org/article/3d52f5c20ac542fd8efc9f44df47386e
Description
Summary:This study examines the physiological response of the Atlantic surfclam ( Spisula solidissima ) to ocean acidification in warm summer temperatures. Working with ambient seawater, this experiment manipulated pH conditions while maintaining natural diel fluctuations and seasonal shifts in temperature. One-year-old surfclams were exposed to one of three pH conditions (ambient (control): 7.8 ± 0.07, medium: 7.51 ± 0.10, or low: 7.20 ± 0.10) in flow-through conditions for six weeks, and feeding and digestive physiology was measured after one day, two weeks, and six weeks. After six weeks of exposure to medium and low pH treatments, growth was not clearly affected, and, contrastingly, feeding and digestive physiology displayed variable responses to pH over time. Seemingly, low pH reduced feeding and absorption rates compared to both the medium treatment and ambient (control) condition; however, this response was clearer after two weeks compared to one day. At six weeks, suppressed physiological rates across both pH treatments and the ambient condition suggest thermal stress from high ambient water temperatures experienced the week prior (24–26 °C) dominated over any changes from low pH. Results from this study provide important information about reduced energy acquisition in surfclams in acidified environments and highlight the need for conducting multistressor experiments that consider the combined effects of temperature and pH stress.