Fiddling with the blue carbon: Fiddler crab burrows enhance CO2 and CH4 efflux in saltmarsh

Saltmarshes are important global carbon (C) sinks, but the considerable uncertainty in C budget and underlying mechanisms limit estimation of greenhouse gas emissions (GHG, e.g., CO2 CH4) context climate change. To ascertain mechanistic understanding, we assessed how crab burrows morphology effluxes changed response to interactions fiddler burrow density, soil organic matter content (high vs low), presence/absence Spartina alterniflora (vegetated saltmarsh nearby unvegetated mudflat) on coast New England (USA). The volume vegetated was smaller than that mudflat, greatly correlated with efflux, indicating activities could enhance coastal wetland efflux. Soil CH4 rates were significantly positively content, vegetation types. Specifically, higher density increased heterotrophic respiration saltmarsh. Overall, disturbances, efflux by 32.1% 47.9%, respectively. This study highlights burrowing activity plays an role sequestration blue ecosystems (BCEs).