title: Production of fluorescent dissolved organic matter in Arctic Ocean sediments.
abstract: Little is known about the production of fluorescent dissolved organic matter (FDOM) in the anoxic oceanic sediments. In this study, sediment pore waters were sampled from four different sites in the Chukchi-East Siberian Seas area to examine the bulk dissolved organic carbon (DOC) and their optical properties. The production of FDOM, coupled with the increase of nutrients, was observed above the sulfate-methane-transition-zone (SMTZ). The presence of FDOM was concurrent with sulfate reduction and increased alkalinity (R2> 0.96, p < 0.0001), suggesting a link to organic matter degradation. This inference was supported by the positive correlation (R2> 0.95, p < 0.0001) between the net production of FDOM and the modeled degradation rates of particulate organic carbon sulfate reduction. The production of FDOM was more pronounced in a shallow shelf site S1 with a total net production ranging from 17.9 to 62.3 RU for different FDOM components above the SMTZ depth of ca. 4.1 mbsf, which presumably underwent more accumulation of particulate organic matter than the other three deeper sites. The sediments were generally found to be the sources of CDOM and FDOM to the overlying water column, unearthing a channel of generally bio-refractory and pre-aged DOM to the oceans.
authors.affiliation: Department of Environment &Energy, Sejong University, Seoul 05006, South Korea.
authors.forename: Meilian
authors.initials: M
authors.lastname: Chen
authors.affiliation: Petroleum &Marine Division, Korea Institute of Geoscience and Mineral Resources, 124 Gwahang-no, Yuseong-gu, Daejeon 34132, South Korea.
authors.forename: Ji-Hoon
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Division of Polar Paleoenvironment Korea Polar Research Institute, Incheon 21990, South Korea.
authors.forename: Seung-Il
authors.initials: SI
authors.lastname: Nam
authors.affiliation: Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI), Am Alten Hafen 26, 27568 Bremerhaven, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Niessen
authors.affiliation: CAGE - Centre for Arctic Gas Hydrate, Environment and Climate, Department of Geology, UiT The Arctic University of Norway, Tromsø, Norway.
authors.forename: Wei-Li
authors.initials: WL
authors.lastname: Hong
authors.affiliation: Petroleum &Marine Division, Korea Institute of Geoscience and Mineral Resources, 124 Gwahang-no, Yuseong-gu, Daejeon 34132, South Korea.
authors.forename: Moo-Hee
authors.initials: MH
authors.lastname: Kang
authors.affiliation: Department of Environment &Energy, Sejong University, Seoul 05006, South Korea.
authors.forename: Jin
authors.initials: J
authors.lastname: Hur