1-s2.0-0304420395000623-main

1-s2.0-0304420395000623-mainELSEVIERMarineChemistry51(1996)325-346CharacterizationofmarineandterrestrialDOMinseawaterusingexcitation-emissionmatrixspectroscopyPaulaG.CobleUniversityofSouthFloridaatSt.Petersburg,DepartmentofMarineScience,140SeventhAwe.S.,St.Petersburg,FL33701,USAReceived1March1995;accepted23June1995AbstractHigh-resolutionfluorescencespectroscopywasusedtocharacterizedissolvedorganicmatter(DOM)inconcentratedandunconcentratedwatersamplesfromawidevarietyoffreshwater,coastalandmarineenvironments.Severaltypesoffluorescentsignalswereobserved,includinghumic-like,tyrosine-like,andtryptophan-like.Humic-likefluorescenceconsistedoftwopeaks,onestimulatedbyUVexcitation(peakA)andonebyvisibleexcitation(peakC).Forallsamples,thepositionsofbothexcitationandemissionmaximaforpeakCweredependentuponwavelengthofobservation,withashifttowardslongerwavelengthemissionmaximumatlongerexcitationwavelengthandlongerwavelengthexcitationmaximumatlongeremissionwavelength.Atrendwasobservedinthepositionofwa