Mudflats Should Be Considered a Blue Carbon Ecosystem

Abstract:

Coastal ecosystems are widely recognized to be able to sequester large amounts of carbon. These habitats, often termed “blue carbon” ecosystems, are typically considered to include marshes, mangroves, and sea grasses. Sometimes grouped with these are kelp forests and coral reefs. We argue that unvegetated coastal mudflats in intertidal areas have the potential to store amounts of carbon high enough to be considered blue carbon habitats. Using data from the literature, we find that mudflats routinely contain 5-10% organic matter. Given potentially high accretion rates, ample accommodation space, and the large spatial extent of mudflats, we find that these systems contain an amount of organic matter similar to that of marsh systems. Here we provide one of the first estimates of carbon stock in mudflat systems worldwide and discuss the data needed to improve the quality of this estimate.