简介：Dissolvedandparticulatethorium-234,particulateorganiccarbonintheupper150mofwatercolumnsfromfivestationsinthePrydzBay,theSouthernOceanweredeterminedduringthe22ndChineseNationalAntarcticResearchExpedition(fromNovember2005toMarch2006).Thedisequilibriabetweenthorium-234anditsparenturanium-238inupperlayerwasusedtoderivetheaveragedresidencetimeofthorium-234,whichdecreasedalongwiththelatitudetothesouthandaminimumvalue,1~8dforparticulatethorium-234and29~48dfordissolvedthorium-234,appearedatthemediumlatitudestation,andtheexportfluxesofthorium-234werecalculatedtooandamaximumvalue,0.35~0.63Bq/(m3·d)fortheparticulatethorium-234and0.44~0.65Bq/(m3·d)forthedissolvedthorium-234,appearedatthesamestation.Theexportfluxesofparticulateorganiccarbonatdifferentwatercolumnswerederivedbytwomethodswithirreversiblescavengingmodel,andtheaveragedvalueswere104.7mmol/(m2·d)(Emethod)and120.6mmol/(m2·d)(Bmethod),respectively,indicatingthatarelativelyhighnewproductionwouldexistinsummerinthePrydzBaywhereitwillplayapotentialsignificantroleinsequesteringtheabsorptionCO2todeeperocean.