Thechemicalcharacteristicsofprecipitationwereanalyzedbasedonthechemicalcompositionofprincipalionicwithinacidrain（fromFebruary2007toJanuary2008）ofLiaozhongMeteorologicalStationlocatedinMalongVillageinLiaozhongCountyofNortheastChina,meteorologicalconditionsonthecorrespondingperiodground,andvariationofseveralairpollutantsconcentration.Theresultsindicatedthat:（1）TheprecipitationaveragepHvalueofallsampleswas4.76;thefrequencyofacidrainduringtheobservationperiodwas70.7%;thefrequencywas82.8%insummerandautumn.（2）Inthechemicalcompositionofprecipitation,theprimaryanionswereSO42-andNO3-;theprimarycationswereNH4+andCa2+.（3）Allconcentrationofanionswashigherinsummerandwinter,butrelativelylowinspringandautumn.Thisshowedthattherelationshipbetweenregionalrainfallacidificationandpollutionwasnotsignificant.（4）Rainwateracidityandnearlyfloorgaseouspollutionconcentrationweredifferentfromeachother,andpHandNOx,CO,NO2andO3concentrationsshowedsignificantnegativecorrelation,butwasnotobviouswithSO2concentration.However,thepHandalkalinepollutants,suchasparticulate,waspositivelycorrelative.
