Dataset Information

A global assessment of the mixed layer in coastal sediments and implications for carbon storage.

ABSTRACT: The sediment-water interface in the coastal ocean is a highly dynamic zone controlling biogeochemical fluxes of greenhouse gases, nutrients, and metals. Processes in the sediment mixed layer (SML) control the transfer and reactivity of both particulate and dissolved matter in coastal interfaces. Here we map the global distribution of the coastal SML based on excess ²¹⁰Pb (²¹⁰Pb_ex) profiles and then use a neural network model to upscale these observations. We show that highly dynamic regions such as large estuaries have thicker SMLs than most oceanic sediments. Organic carbon preservation and SMLs are inversely related as mixing stimulates oxidation in sediments which enhances organic matter decomposition. Sites with SML thickness >60 cm usually have lower organic carbon accumulation rates (<50 g C m^-2 yr^-1) and total organic carbon/specific surface area ratios (<0.4 mg m^-2). Our global scale observations reveal that reworking can accelerate organic matter degradation and reduce carbon storage in coastal sediments.

SUBMITTER: Song S

PROVIDER: S-EPMC9392783 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

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A global assessment of the mixed layer in coastal sediments and implications for carbon storage.

Song Shasha S Santos Isaac R IR Yu Huaming H Wang Faming F Burnett William C WC Bianchi Thomas S TS Dong Junyu J Lian Ergang E Zhao Bin B Mayer Lawrence L Yao Qingzhen Q Yu Zhigang Z Xu Bochao B

Nature communications 20220820 1

The sediment-water interface in the coastal ocean is a highly dynamic zone controlling biogeochemical fluxes of greenhouse gases, nutrients, and metals. Processes in the sediment mixed layer (SML) control the transfer and reactivity of both particulate and dissolved matter in coastal interfaces. Here we map the global distribution of the coastal SML based on excess 210Pb (210Pbex) profiles and then use a neural network model to upscale these observations. We show ...[more]

PMID: 35987905

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Dataset Information

A global assessment of the mixed layer in coastal sediments and implications for carbon storage.

Publications

A global assessment of the mixed layer in coastal sediments and implications for carbon storage.

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