Spilmont & Zardi (2025): Intertidal mussel–symbiont associations act as CO₂ sinks during daily emersion
Nicolas Spilmont; Gerardo I. Zardi, IN: Biology Letters, https://doi.org/10.1098/rsbl.2025.0498
Human activities have disrupted the global carbon cycle, reducing carbon dioxide (CO₂) uptake by tidal wetlands and submerged vegetation. This exacerbates climate challenges, including rising temperatures and ocean acidification. Coastal systems such as mangroves and seagrasses serve as key carbon sinks, promising for CO₂ removal (CDR). Growing attention is being given to bivalves, whose calcification and reef-building activities shape coastal carbon dynamics. Most studies reduce bivalve impacts to a balance between individual CO₂ emissions and the carbon stored in their shells and tissues, often overlooking species interactions—such as symbioses—that may modulate carbon fluxes. Here, the authors examined the mussel–symbiont holobiont using Mytilus edulis under emersion in a controlled chamber to quantify CO₂ exchange.