Skeletal magnesium content in Antarctic echinoderms along a latitudinal gradient

Area of Science:

• Marine Biology
• Biogeochemistry
• Climate Change Science

Background:

• Anthropogenic carbon dioxide (CO₂) emissions cause ocean warming and acidification.
• These changes can alter the mineral composition of marine calcifiers.
• Polar regions may experience greater impacts due to CO₂'s increased solubility at lower temperatures.

Purpose of the Study:

• To investigate the influence of environmental factors on skeletal magnesium (Mg) content in Antarctic echinoderms.
• To assess Mg content across different echinoderm classes (Asteroidea, Ophiuroidea, Echinoidea, Holothuroidea) along a latitudinal gradient.

Main Methods:

• Sampling of Antarctic echinoderms from the South Shetland Islands to Rothera (Adelaide Island).
• Analysis of skeletal magnesium content in various echinoderm classes.
• Comparison of Mg content across a latitudinal environmental gradient.

Main Results:

• All analyzed skeletal structures, except for echinoid spines, displayed high Mg content.
• Asteroids exhibited the highest skeletal Mg levels among the studied groups.
• Skeletal Mg content variability was greater in ophiuroids and echinoids, suggesting higher environmental influence.

Conclusions:

• Asteroids and holothuroids possess a strong biological capacity to regulate Mg incorporation into their skeletons.
• Ophiuroids and echinoids show greater susceptibility to local environmental conditions affecting skeletal Mg content.
• Species-specific responses to climate change are expected due to differing environmental influences on skeletal Mg content.