title: Variability of sedimentary organic carbon in patchy seagrass landscapes.
abstract: 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 (δ(13)C, 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.
authors.affiliation: Departament d'Ecologia, Universitat de Barcelona, Av Diagonal 643 6a planta, 08028 Barcelona, Spain. Electronic address: auroramartinez@ub.edu.
authors.forename: Aurora M
authors.initials: AM
authors.lastname: Ricart
authors.affiliation: Centre for Tropical Water and Aquatic Ecosystem Research, James Cook University, PO Box 6811, Cairns, QLD 4870, Australia.
authors.forename: Paul H
authors.initials: PH
authors.lastname: York
authors.affiliation: Centre for Tropical Water and Aquatic Ecosystem Research, James Cook University, PO Box 6811, Cairns, QLD 4870, Australia.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Rasheed
authors.affiliation: Departament d'Ecologia, Universitat de Barcelona, Av Diagonal 643 6a planta, 08028 Barcelona, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Pérez
authors.affiliation: Departament d'Ecologia, Universitat de Barcelona, Av Diagonal 643 6a planta, 08028 Barcelona, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Romero
authors.affiliation: Centre for Tropical Water and Aquatic Ecosystem Research, James Cook University, PO Box 6811, Cairns, QLD 4870, Australia.
authors.forename: Catherine V
authors.initials: CV
authors.lastname: Bryant
authors.affiliation: Plant Functional Biology and Climate Change Cluster, University of Technology Sydney, PO Box 123, Sydney, NSW 2007, Australia; Centre for Integrative Ecology, School of Life and Environmental Sciences, Faculty of Science Engineering and Built Environment, Deakin University, Burwood, VIC 3125, Australia.
authors.forename: Peter I
authors.initials: PI
authors.lastname: Macreadie
mesh_terms: D002244:Carbon / Q000032:analysis*; D002247:Carbon Isotopes / Q000032:analysis; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods; D019015:Geologic Sediments / Q000032:analysis*; D010316:Particle Size; D011793:Queensland; D035962:Zosteraceae
chemical_list: D002247:Carbon Isotopes; D002244:Carbon
keywords: Blue carbon; Carbon stock; Climate change; Marine sediment; Patchiness; Zostera muelleri