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TopicI:GlobalcooperationtoprotectthemarineenvironmentIntroductiontotheproblemThemarineenvironmentcanbedescribedorcharacterizedatanumberofdifferentscales,rangingfromocean-levelprocessesthroughtothosethatoccuratspeciesandgeneticlevel(Connoretal.2002).Thescalesofrelevanceherearemarinelandscapes,habitatsandspecies;theirinter-relationshipcanbeexpressedasfollows:Speciesprovidethegloballyacceptedoriginalclassificationofbiologicaldiversity,withwell-establishedrulesoftaxonomytodistinguishbetweendifferenttypes.Theirclassificationisarrangedinahierarchyofgenera,families,orders,classesandphyla.Habitatscomprisesuitesofspecies(communitiesorassemblages)thatconsistentlyoccurtogether,butwhicharederivedfromdifferentpartsofthetaxonomichierarchy(e.g.kelps,molluscsandfishinakelpforesthabitat).Theirclassificationcanalsobestructuredinahierarchy(biotopes,biotopecomplexes,broadhabitats),reflectingdegreesofsimilarityMarineLandscapescomprisesuitesofhabitatsthatconsistentlyoccurtogether,butwhichareoftenderivedfromdifferentpartsofthehabitatclassificationhierarchy(e.g.salt-marshintertidalmudflats,rockyshoresandsub-tidalmusselbedsinanestuary).DifferenttypesofpollutionPollutionfromshipsShipscanpollutewaterwaysandoceansinmanyways.Oilspillscanhavedevastatingeffects.Whilebeingtoxictomarinelife,polycyclicaromatichydrocarbons(PAHS)foundincrudeoil,areverydifficulttocleanup,andlastforyearsinthesedimentandmarineenvironment.Dischargeofcargoresiduesfrombulkcarrierscanpolluteports,waterwaysandoceans.Inmanyinstancesvesselsintentionallydischargeillegalwastesdespiteforeignanddomesticregulationprohibitingsuchactions.Ithasbeenestimatedthatcontainershipsloseover10,000containersatseaeachyear(usuallyduringstorms).Shipsalsocreatenoisepollutionthatdisturbsnaturalwildlife,andwaterfromballasttankscanspreadharmfulalgaeandotherinvasivespecies.AtmospherepollutionGraphlinkingatmosphericdusttovariouscoraldeathsacrosstheCaribbeanSeaandFloridaAnotherpathwayofpollutionoccursthroughtheatmosphere.Windblowndustanddebris,includingplasticbags,areblownseawardfromlandfillsandotherareas.DustfromtheSaharamovingaroundthesouthernperipheryofthesubtropicalridgemovesintotheCaribbeanandFloridaduringthewarmseasonastheridgebuildsandmovesnorthwardthroughthesubtropicalAtlantic.DustcanalsobeattributedtoaglobaltransportfromtheGobiandTaklamakandesertsacrossKorea,Japan,andtheNorthernPacifictotheHawaiianIslands.Since1970,dustoutbreakshaveworsenedduetoperiodsofdroughtinAfrica.ThereisalargevariabilityindusttransporttotheCaribbeanandFloridafromyeartoyear;however,thefluxisgreaterduringpositivephasesoftheNorthAtlanticOscillation.TheUSGSlinksdusteventstoadeclineinthehealthofcoralreefsacrosstheCaribbeanandFlorida,primarilysincethe1970s.AcidificationIslandwithfringingreefintheMaldives.Coralreefsaredyingaroundtheworld.Theoceansarenormallyanaturalcarbonsink,absorbingcarbondioxidefromtheatmosphere.Becausethelevelsofatmosphericcarbondioxideareincreasing,theoceansarebecomingmoreacidic.Thepotentialconsequencesofoceanacidificationarenotfullyunderstood,butthereareconcernsthatstructuresmadeofcalciumcarbonatemaybecomevulnerabletodissolution,affectingcoralsandtheabilityofshellfishtoformshells.Oceansandcoastalecosystemsplayanimportantroleintheglobalcarboncycleandhaveremovedabout25%ofthecarbondioxideemittedbyhumanactivitiesbetween2000and2007andabouthalftheanthropogenicCO2releasedsincethestartoftheindustrialrevolution.Risingoceantemperaturesandoceanacidificationmeansthatthecapacityoftheoceancarbonsinkwillgraduallygetweaker,givingrisetoglobalconcernsexpressedintheMonacoandManadoDeclarations.PlasticdebrisMarinedebrisismainlydiscardedhumanrubbishwhichfloatson,orissuspendedintheocean.Eightypercentofmarinedebrisisplastic-acomponentthathasbeenrapidlyaccumulatingsincetheendofWorldWarII.Themassofplasticintheoceansmaybeashighasonehundredmillionmetrictons.Discardedplasticbags,sixpackringsandotherformsofplasticwastewhichfinishupintheoceanpresentdangerstowildlifeandfisheries.Aquaticlifecanbethreatenedthroughentanglement,suffocation,andingestion.Fishingnets,usuallymadeofplastic,canbeleftorlostintheoceanbyfishermen.Knownasghostnets,theseentanglefish,dolphins,seaturtles,sharks,dugongs,crocodiles,seabirds,crabs,andothercreatures,restrictingmovement,causingstarvation,lacerationandinfection,and,inthosethatneedtoreturntothesurfacetobreathe,suffocation.RemainsofanalbatrosscontainingingestedflotsamManyanimalsthatliveonorintheseaconsumeflotsambymistake,asitoftenlookssimilartotheirnaturalprey.Plasticdebris,whenbulkyortangled,isdifficulttopass,andmaybecomepermanentlylodgedinthedigestivetractsoftheseanimals,blockingthepassageoffoodandcausingdeaththroughstarvationorinfection.Plasticsaccumulatebecausetheydon'tbiodegradeinthewaymanyothersubstancesdo.Theywillphotodegradeonexposuretothesun,buttheydosoproperlyonlyunderdryconditions,andwaterinhibitsthisprocess.[50]Inmarineenvironments,photodegradedplasticdisintegratesintoeversmallerpieceswhileremainingpolymers,evendowntothemolecularlevel.Whenfloatingplasticparticlesphotodegradedowntozooplanktonsi