TheValueoftheWorld'sEcosystemServicesandNaturalCapitalbyCostanzain1997isgenerallyre-gardedasamonumentfortheresearchofvaluingecosystemservices.However,theclassificationofecosystemser-vices,themethodofvariousservicessummationandthepurposeforstaticglobalvaluehadbeconfrontedbymanycriticisms.Basedonthesummaryofthesecriticisms,suggestions,relatedfunctionassessmentandfurtherstudydirection,thesustainabilityofecosystemservicesispresented.Thetwobasicindicatorsinecology,productivityandbiopersity,respectivelycharacteringtheabilityofproducingandself-organizing,notonlyrepresenttheinternalfunctionofecosystem,butalsoareproportionedtoitsexternalfunctionofsupportingandprovidingforhumanlife.Onpresentingthegeneralformofecosystemservicesassessment,thispaperimprovesthemathematicalformulabygivingafunctionadjustingcoefficientcomposedofproductivityandbiopersity.Theoretically,theintegrationofthetwoindicatorsreflectsthechangesofecosystemservicesatspatialandtemporalscales,canphysicallyassessthesustainabilityofecosystemservices,andbuildafirmscientificfundamentofvalueassessmentforecosystemservices.Objectively,itsapplicationshouldbestrictlytestedinnextstep.
