简介：Phosphorus(P)fractionsandtheirbioavailabilityinthesedimentsfromElMexBayandLakeMariutinEgyptwereinvestigatedusingdifferentchemicalextractionmethods.Sodiumbicarbonate(NaHCO3)extractableP(Olsen-P)wasthelargestfraction(14.42%),followedbyalgalavailableP(AAP)(3.56%),watersolubleP(WSP)(0.79%),andreadilydesorbableP(RDP)(0.06%)forElMexBay.WhileAAPcontributed9.94%tototalPinsedimentsfromLakeMariut,Olsen-P8.53%,WSP4.11%,andRDP0.92%.SummationofthebioavailablePfractionsdidn'texceedthesedimentqualityguidelines,and,therefore,Pdoesn'trepresentadangertomarineorganisms.CorrelationcoefficientsshowedthatnoapparentrelationsbetweentotalP(TP)andiron(Fe),aluminum(Al),andcalcium(Ca)inthesediments.Furthermore,Fe:Pratiowaslessthan15indictingthattherewasnotenoughFeinsurfacesedimentstobindtoPatmostofthesamplingsites.ThepositivecorrelationbetweenTPandorganicmatter(OM)forLakeMariutandElMexBaysedimentsindicatedthattheorganicmattercontentofthesedimentwasausefulpredictorofthetotalphosphoruscontent.DatafromthisstudyconstituteabaselineofphosphorusbioavailabilityinsedimentsfromElMexBayandLakeMariutandcouldbeusedasareferenceforfuturestudiesonthechangesofbioavailableandresidualphosphorusfractionsovertime.