CIE Spotlight: Variability of sedimentary organic carbon in patchy seagrass landscapes

Peter M.
Peter M.

Title: Variability of sedimentary organic carbon in patchy seagrass landscapes

Authors: Aurora M. Ricart, Paul H. York, Michael A. Rasheed, Marta Pérez, Javier Romero, Catherine V. Bryant and Peter I. Macreadie

Source: Marine Pollution Bulletin, Volume 100, Issue 1, 15 November 2015, Pages 476–482

Brief summary of the paper: Seagrass ecosystems, considered among the most efficient carbon sinks worldwide, encompass a wide variety of spatial configurations in the coastal landscape.

Here we evaluated the influence of the spatial configuration of seagrass meadows at small scales (metres) on carbon storage in seagrass sediments. We intensively sampled carbon stocks and other geochemical properties (δ13C, particle size, depositional fluxes) across seagrass–sand edges in a Zostera muelleri patchy seagrass landscape.

Carbon stocks were significantly higher (ca. 20%) inside seagrass patches than at seagrass–sand edges and bare sediments. Deposition was similar among all positions and most of the carbon was from allochthonous sources. Patch level attributes (e.g. edge distance) represent important determinants of the spatial heterogeneity of carbon stocks within seagrass ecosystems.

Our findings indicate that carbon stocks of seagrass areas have likely been overestimated by not considering the influence of meadow landscapes, and have important relevance for the design of seagrass carbon stock assessments.