简介：Theclosed-jarincubationmethodiswidelyusedtoestimatethemineralizationofsoilorganicC.TherearetwoCpools(i.e.,organicandinorganicC)incalcareoussoil.ToevaluatetheeffectofadditionalcarbonatesonCO2emissionfromcalcareoussoilduringclosed-jarincubation,threeincubationexperimentswereconductedbyaddingdifferenttypes(CaCO3andMgCO3)andamountsofcarbonatetothesoil.TheadditionofcarbonatessignificantlyincreasedCO2emissionfromthesoil;theincreaserangedfrom12.0%intheCaCO3amendedsoilto460%intheMgCO3amendedsoilduringa100-dincubation.CumulativeCO2productionattheendoftheincubationwasthreetimesgreaterintheMgCO3amendedsoilcomparedtotheCaCO3amendedone.TheCO2emissionincreasedwiththeamountofCaCO3addedtothesoil.Incontrast,CO2emissiondecreasedastheamountofMgCO3addedtothesoilincreased.Ourresultsconfirmedthattheclosed-jarincubationmethodcouldleadtoanoverestimateoforganicCmineralizationincalcareoussoils.BecauseofitseffectonsoilpHandthedissolutionofcarbonates,HgCl2shouldnotbeusedtosterilizecalcareoussoiliftheexperimentincludesthemeasurementofsoilCO2production.