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This study conducted the first comprehensive investigation of sedimentary black carbon (BC) concentration, flux, and budget in the continental shelves of "Bohai Sea (BS) and Yellow Sea (YS)," based on measurements of BC in 191 surface sediments, 36 riverine water, and 2 seawater samples, as well as the reported data set of the atmospheric samples from seven coastal cities in the Bohai Rim. BC concentrations in these matrices were measured using the method of thermal/optical reflectance. The spatial distribution of the BC concentration in surface sediments was largely influenced by the regional hydrodynamic conditions, with high values mainly occurring in the central mud areas where fine-grained particles (median diameters > 6 Φ (i.e., <0.0156 mm)) were deposited. The BC burial flux in the BS and YS ranged from 4 to 1100 μg/cm 2 yr, and averaged 166 ± 200 μg/cm 2 yr, which was within the range of burial fluxes reported in other continental shelf regimes. The area-integrated sedimentary BC sink flux in the entire BS and YS was~325 Gg/yr, and the BS alone contributed~50% (~157 Gg/yr). The BC budget calculated in the BS showed that atmospheric deposition, riverine discharge, and import from the Northern Yellow Sea (NYS) each contributed~51%, 47%, and~2%. Therefore, atmospheric deposition and riverine discharge dominated the total BC influx (~98%). Sequestration to bottom sediments was the major BC output pattern, accounting for~88% of the input BC. Water exchange between the BS and the NYS was also an important BC transport route, with net BC transport from the BS to the NYS.

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[1] The distribution and fate of dichlorodiphenyltrichloroethanes (DDTs) and hexachlorocyclohexanes (HCHs) in sediments from the East China Sea (ECS) and the Yellow Sea (YS) were compared and studied in this work. The ECS has directly large river-dominated inputs of sedimentassociated pollutants while the YS does not. The results indicated that these mud deposits of the YS and ECS were the sinks of land-originated DDTs and HCHs. The consistence of these OCP species and total organic carbon (TOC) and the sediment grain size in the YS indicated that the shelf mud depositional process was the dominant factor in controlling the distribution and fate of these organic compounds under the more homogeneous and hydrodynamicbased sedimentary conditions of the YS. The distribution of these chemicals in the coastal ECS, however, showed a much different pattern where the concentrations of DDTs and HCHs decreased with distance from the coast, and the correlations between DDTs and HCHs with TOC were very poor. This indicates that the continuous transferring of organochlorine pesticides (OCPs) into the coastal ECS by the direct riverine inputs and surface runoffs play a key role on the occurrence and fate of OCPs within this more heterogeneous environmental system. Citation: Hu, L. M., T.