Structurally stable but functionally disrupted marine microbial communities under a future climate change scenario:...

Area of Science:

• Marine Biology
• Environmental Science
• Microbiology

Background:

• The blue mussel (Mytilus edulis) is ecologically vital in the North Sea.
• Mussel shells host microbial biofilms that produce nitrous oxide (N2O), a potent greenhouse gas.
• Understanding climate change effects on these biofilms is crucial.

Purpose of the Study:

• To investigate the impact of increased temperature and decreased pH on Mytilus edulis microbial shell biofilms.
• To assess changes in microbial community structure and biofilm function under simulated climate change conditions.

Main Methods:

• Experimental exposure of M. edulis to combined temperature and pH changes for six weeks.
• Amplicon sequencing (16S rRNA gene) to analyze microbial community diversity and structure.
• Measurement of aerobic respiration and nitrogen emission rates to assess biofilm function.

Main Results:

• No significant impacts of climate change treatments on mussel microbiome diversity or structure were observed.
• Lowered pH and increased temperature showed antagonistic effects on microbial community function.
• Acidification overrode warming effects on N2O emissions when factors were combined, reducing overall emissions.

Conclusions:

• While combined acidification and warming reduce N2O emissions from mussel biofilms, the expansion of shellfish aquaculture may still lead to substantial greenhouse gas emissions.
• Further research is needed to balance aquaculture development with climate change mitigation strategies.