简介：Upwellingcoastalsystemscanbeusedtounderstandhowdissolvedoxygenandbiologicalproductivitycontroltheaccumulationofredox-sensitivemetalsinmarinesediments.Thealuminium(Al),cadmium(Cd),iron(Fe),nickel(Ni),molybdenum(Mo),vanadium(V),totalorganiccarbon(TOC),totalnitrogen(TN)andtotalsulfur(TS)contentsinsurficialsedimentcollectedfromdifferentwaterdepths(30,70,and120m)inthreenorthernChileanbaysinfluencedbycoastalupwellingandoxygenminimumzones(OMZs)weremeasured.Principalcomponentanalysis(PCA),clusteranalysis,andSpearman'srankcorrelationwereusedtoidentifythemechanismsresponsiblefortheredox-sensitivemetalaccumulation.Thecontentofredox-sensitivemetalsandorganiccomponentsinsedimentincreasedwithincreasingwatercolumndepth,whereaslithogenicmetalsdecreased.IntheMejillonesdelSurandCalderabays,theenrichmentfactorsoftheredox-sensitivemetalsshowedenrichmentforallmetalswithdepth.TheCdandVenrichmentsaremainlytheproductofbiogenicflowtotheseabed,andtheMoandNienrichmentsareduetopreservationunderlowsubsurfaceoxygenconditions.Sulfatereductionisnotanimportantmechanismintheaccumulationofredox-sensitivemetalsinthesedimentofthethreebays.ThePCAshowedthatthebehaviorsoftheredox-sensitivemetalsandorganiccomponentsreflectdifferencesintheeffectsoftheOMZinsedimentalongthecoastofnorthernChile,withamoreintenseOMZinMejillonesdelSurbayandweakerOMZsinCalderaandInglesabays.However,thehighdegreeofenrichmentinredox-sensitivemetalsinCalderaBaycanbeattributedtotheintenseactivityoftheminingindustrynearthebay,asituationthatproducesgeochemicalbehaviorsimilartothatobservedinMejillonesdelSurBay.