Distribution patterns of 210Po, 210Pb and the particle export in the Taiwan Strait during the winter

210Po and210Pb are increasingly used to constrain particle dynamics in the open oceans, however they are less used in coastal waters. Here, distributions and partitions of210Po and210Pb were examined in the Taiwan Strait, as well as their application to quantify particle sinking. Activity concentrations of dissolved210Po and210Pb(<0.6 μm)ranged from 1.21 to 7.63 dpm/(100 L) and from 1.07 to 6.33 dpm/(100 L), respectively. Activity concentrations of particulate210Po and210Pb varied from 1.96 to 36.74 dpm/(100 L) and from 3.11 to 38.06 dpm/(100 L). Overall,particulate210Po and210Pb accounted for the majority of the bulk210Po and210Pb. 210 Po either in dissolved or particulate phases showed similar spatial patterns to 210 Pb, indicating similar mechanisms for controlling the distributions of210Po and210Pb in the Taiwan Strait. The different fractionation coefficients indicated that particles in the Zhemin Coastal Current(ZCC) inclined to absorb 210 Po prior to 210 Pb while they showed an opposite effect in the Taiwan Warm Current(TWC). Based on the disequilibria between210Po and210Pb, the sinking fluxes of total particulate matter(TPM) were estimated to range from –0.22 to 3.84 g/(m2·d), showing an overall comparable spatial distribution to previous reported sediment accumulation rates. However, our sinking fluxes were lower than the sedimentation rates, indicating a sediment resuspension in winter and horizontal transport of particulate matter from the Taiwan Strait to the East China Sea.