Preliminary Study on the Responses of Three Marine Algae,Ulva pertusa ( Chlorophyta ) , Gelidium amansii ( Rhodophyta )and Sargassum enerve ( Phaeophyta), to Nitrogen Source and Its Availability

(整期优先)网络出版时间:2004-01-11
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Anexperimentwasdesignedtoselecteconomicallyvaluablemacroalgaspecieswithhighnutrientuptakerates.Suchspeciesculturedonalargescalecouldbeapotentialsolutiontoeutrophication.Threemacroalgaespecies,Ulvapertusa(Chlorophyta),Gelidiumamansii(Rhodophyta)andSargassumenerve(Phaeophyta),werechosenfortheexperimentbecauseoftheireconomicvaluesandavailability.ControlandfournitrogenconcentrationswereachievedbyaddingNH4andNO3.Theresultsindicatethatthefreshweightsofallspeciesincreasefasterthanthatofcontrolafter5dculture.ThefreshweightofUlvapertusaincreasesfastestamongthe3species.However,differentspeciesshowdifferentresponsestonitrogensourceanditsavailability.TheyalsoshowtheadvantageofusingNH+4thanusingNO-3.U.Pertusagrowsbestandshowshighercapabilityofremovingnitrogenat200μmolL-1,butithaslowereconomicalvalue.G.Amansiihashighereconomicalvaluebutlowercapabilityofremovingnitrogenat200μmolL-1.ThecapabilityofnitrogenassimilationofS.EnerveishigherthanthatofG.Amansiiat200μmolL-1,buttheformer'sincreaseoffreshweightislowerthanthoseofothertwospecies.Thenpresentpreliminarystudydemonstratesthatitispossibletousemacroalgaeasbiofiltersandfurtherdevelopmentofthisapproachcouldprovidebiologicallyvaluableinformationonthesource,fate,andtransportofNinmarineecosystems.Cautionisneededshouldweextrapolatethesefindingstonaturalenvironments.