简介：AmongthenumerousinlandriverbasinsinthearidnorthwestChina,ShiyangRiverbasinisknownforitsmostseriouswatershortagethatconstrainsitssocialandeconomicdevelopmentsandforsomeoftheworstecologicalandenvironmentaldeteriorationinChina.Theresearchonthevalueofwaterresourcesusedforecosystemisthebasisforreasonableallocationofwaterresourcesbetweenusersofecosystemandeconomicsystem.Inthispapertheconceptofdynamicvaluefortheecosystemservicesisproposed.Amodifiedcoefficientfortheecosystemservicevalueperunitareaisproposedaccordingtothecoverdegreesofbiomescombinedwithexpertconsultation.Basedonthedevelopmentalstagecoefficientandscarcityofecologicalresources,adynamicevaluationmethodisproposed.Thetheoreticalformulaandsimplecalculationformulaofthesharingbenefitscoefficientandbenefitsperunitecologicalwaterutilizationareproposed.TheresultshowsthatthebenefitofunitecologicalwaterutilizationinthelowerreachwasgreaterthanthatintheupperreachintheShiyangRiverbasin.