Mangrove production and carbon sinks: A revision of global budget estimates

Authors

Steven Bouillon, Department of Analytical and Environmental Chemistry, Vrije Universiteit Brussel
Alberto V. Borges, Chemical Oceanography Unit, University of Liège
Edward Castañeda-Moya, Department of Oceanography and Coastal Science, Wetland Biogeochemistry Institute, Louisiana State UniversityFollow
Karen Diele, Zentrum für Marine Tropenökologie
Thorsten Dittmar, Department of Oceanography, Florida State University
Norman C. Duke, Australian Rivers Institute–Coasts and Estuaries, Griffith University Gold Coast
Erik Kristensen, Institute of Biology, University of Southern Denmark
Shing Y. Lee, Australian Rivers Institute–Coasts and Estuaries, Griffith University Gold Coast
Cyril Marchand, UR 103, Institut de Recherche pour le Développement (IRD)
Jack J. Middleburg, Centre for Estuarine and Marine Ecology (NIOO-KNAW), Netherlands Institute of EcologyFollow
Victor H. Rivera-Monroy, Department of Oceanography and Coastal Science, Wetland Biogeochemistry InstituteFollow
Thomas J. Smith III, U.S. Geological Survey, Florida Integrated Science CenterFollow
Robert R. Twilley, Department of Oceanography and Coastal Science, Wetland Biogeochemistry Institute, Louisiana State UniversityFollow

Abstract

Mangrove forests are highly productive but globally threatened coastal ecosystems, whose role in the carbon budget of the coastal zone has long been debated. Here we provide a comprehensive synthesis of the available data on carbon fluxes in mangrove ecosystems. A reassessment of global mangrove primary production from the literature results in a conservative estimate of ∼218 ± 72 Tg C a⁻¹. When using the best available estimates of various carbon sinks (organic carbon export, sediment burial, and mineralization), it appears that >50% of the carbon fixed by mangrove vegetation is unaccounted for. This unaccounted carbon sink is conservatively estimated at ∼112 ± 85 Tg C a⁻¹, equivalent in magnitude to ∼30–40% of the global riverine organic carbon input to the coastal zone. Our analysis suggests that mineralization is severely underestimated, and that the majority of carbon export from mangroves to adjacent waters occurs as dissolved inorganic carbon (DIC). CO₂ efflux from sediments and creek waters and tidal export of DIC appear to be the major sinks. These processes are quantitatively comparable in magnitude to the unaccounted carbon sink in current budgets, but are not yet adequately constrained with the limited published data available so far.

Comments

This material is based upon work supported by the National Science Foundation through the Florida Coastal Everglades Long-Term Ecological Research program under Cooperative Agreements #DBI-0620409 and #DEB-9910514. Any opinions, findings, conclusions, or recommendations expressed in the material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

Recommended Citation

Bouillon, S., et al. (2008), Mangrove production and carbon sinks: A revision of global budget estimates, Global Biogeochem. Cycles, 22, GB2013, doi:10.1029/2007GB003052.