简介：ThecorrectmethodusedinforestsoilrespirationmeasurementbyLi-6400isapremiseofdataqualitycontrol.Accordingtothestudyinalarchplantation,collarsshouldbeinsertedat12hoursinadvancetoefficientlyreducetheinfluenceofCO2spring-out.Moreover,collarinsertiondepthsubstantiallyaffectedsoilrespirationmeasurement,i.e.whencollarwasshallowlyinsertedintosoil,transversalgasdiffusionandtheCO2re-spring-outcausedbyunstablecollarsinthemeasurementcouldleadtooverestimatingsoilrespirationrate;however,whencollarwasdeeplyinsertedintosoil,rootrespirationdeclinecausedbyroot-cutandthemostactiverespiratoryofthesurfacesoilseparatedbytheinsertedcollarscouldleadtounderestimatingsoilrespirationrate.Furthermore,anerrorlessthan5%couldbeguaranteedintypicalsunnydayifthetarget[CO2]wassettothemeanvalueofambient[CO2]inmosttimeoftheday,butitshouldbecarefullysetinearlymorningandlateafternoonaccordingtochangingambient[CO2].Thisprotocolofmeasurementisusefulinrealmeasurement.