210Po and 210Pb are increasingly used to constrain particle dynamics in the open oceans,however they are less used in coastal waters.Here,distributions and partitions of 210Po and 210Pb were examined in the Taiwan Str...210Po and 210Pb are increasingly used to constrain particle dynamics in the open oceans,however they are less used in coastal waters.Here,distributions and partitions of 210Po and 210Pb were examined in the Taiwan Strait,as well as their application to quantify particle sinking.Activity concentrations of dissolved 210Po and 210Pb(<0.6μm)ranged from 1.21 to 7.63 dpm/(100 L)and from 1.07 to 6.33 dpm/(100 L),respectively.Activity concentrations of particulate 210Po and 210Pb varied from 1.96 to 36.74 dpm/(100 L)and from 3.11 to 38.06 dpm/(100 L).Overall,particulate 210Po and 210Pb accounted for the majority of the bulk 210Po and 210Pb.210Po either in dissolved or particulate phases showed similar spatial patterns to 210Pb,indicating similar mechanisms for controlling the distributions of 210Po and 210Pb in the Taiwan Strait.The different fractionation coefficients indicated that particles in the Zhemin Coastal Current(ZCC)inclined to absorb 210Po prior to 210Pb while they showed an opposite effect in the Taiwan Warm Current(TWC).Based on the disequilibria between 210Po and 210Pb,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.展开更多
The geochemical behaviors of dissolved (<0.4 mm), low molecular weight (<10 kDa) and colloidal (10 kDa- 0.4 mm) 210Po in surface waters from the Jiulongjiang estuary were examined and the input/removal rates of ...The geochemical behaviors of dissolved (<0.4 mm), low molecular weight (<10 kDa) and colloidal (10 kDa- 0.4 mm) 210Po in surface waters from the Jiulongjiang estuary were examined and the input/removal rates of different 210Po species were estimated. Both dissolved and low molecular weight 210Po were considerably removed during estuarine mixing. However, colloidal 210Po was removed only at low salinity regions (S <15) but had input behavior at high salin-ity surface waters (S >15). The input/removal rates of three species indicate that 210Po was removed rapidly in the Jiu-longjiang estuary. The discrepancy of input/removal rates between 210Po species suggests different geochemical be-havior and a dynamic transformation between 210Po species. Low molecular weight 210Po may be more appropriate for characterizing the 210Po behavior in estuary zone than the traditional dissolved 210Po.展开更多
基金The National Natural Science Foundation of China under contract Nos 41076043 and 51608142the Guangxi Young and Middle-aged Teachers’ Basic Ability Upgrading Project under contract No.2019KY0298the Guangxi Science and Technology Planning Project under contract No.Gui Ke-AD18126018
文摘210Po and 210Pb are increasingly used to constrain particle dynamics in the open oceans,however they are less used in coastal waters.Here,distributions and partitions of 210Po and 210Pb were examined in the Taiwan Strait,as well as their application to quantify particle sinking.Activity concentrations of dissolved 210Po and 210Pb(<0.6μm)ranged from 1.21 to 7.63 dpm/(100 L)and from 1.07 to 6.33 dpm/(100 L),respectively.Activity concentrations of particulate 210Po and 210Pb varied from 1.96 to 36.74 dpm/(100 L)and from 3.11 to 38.06 dpm/(100 L).Overall,particulate 210Po and 210Pb accounted for the majority of the bulk 210Po and 210Pb.210Po either in dissolved or particulate phases showed similar spatial patterns to 210Pb,indicating similar mechanisms for controlling the distributions of 210Po and 210Pb in the Taiwan Strait.The different fractionation coefficients indicated that particles in the Zhemin Coastal Current(ZCC)inclined to absorb 210Po prior to 210Pb while they showed an opposite effect in the Taiwan Warm Current(TWC).Based on the disequilibria between 210Po and 210Pb,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.
基金supported by the National Natural Science Foundation of China(Grant No.40076024)the 10th Five-Year Plan of COMRA(Grant Nos.DY 105-02-4,DY 105-02-01 and DY 105-01-04-11).
文摘The geochemical behaviors of dissolved (<0.4 mm), low molecular weight (<10 kDa) and colloidal (10 kDa- 0.4 mm) 210Po in surface waters from the Jiulongjiang estuary were examined and the input/removal rates of different 210Po species were estimated. Both dissolved and low molecular weight 210Po were considerably removed during estuarine mixing. However, colloidal 210Po was removed only at low salinity regions (S <15) but had input behavior at high salin-ity surface waters (S >15). The input/removal rates of three species indicate that 210Po was removed rapidly in the Jiu-longjiang estuary. The discrepancy of input/removal rates between 210Po species suggests different geochemical be-havior and a dynamic transformation between 210Po species. Low molecular weight 210Po may be more appropriate for characterizing the 210Po behavior in estuary zone than the traditional dissolved 210Po.
