浮游生物(Plankton)

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scatteredthroughtheseasoftheworldarebillionsoftonsofsmallplantsandanimalscalledplankton.mostoftheseplantsandanimalsaretoosmallforthehumaneyetosee.theydriftaboutlazilywiththecurrents,providingabasicfoodformanylargeranimals.planktonhasbeendescribedastheequivalentofthegrassesthatgrowonthedrylandcontinents,andtheparisonisanappropriateone.

inpotentialfoodvalue,however,planktonfaroutweighsthatofthelandgrasses.onescientisthasestimatedthatwhilegrassesoftheworldproduceabout49billiontonsofvaluablecarbohydrateseachyear,thesea＇splanktongeneratesmorethantwiceasmuch.despiteitsenormousfoodpotential,littleeffectwasmadeuntilrecentlytofarmplanktonaswefarmgrassesonland.nowmarinescientistshaveatlastbeguntostudythispossibility,especiallyasthesea＇sresourcesloomevenmoreimportantasameansoffeedinganexpandingworldpopulation.nooneyethasseriouslysuggestedthat"plankton-burgers"maysoonbeepopulararoundtheworld.asapossiblefarmedsupplementaryfoodsource,however,planktonisgainingconsiderableinterestamongmarinescientists.oypeofplanktonthatseemstohavegreatharvestpossibilitiesisatinyshrimp-likecreaturecalledkrill.growingtotwoorthreeincheslong,krillprovidesthemajorfoodforthegreatbluewhale,thelargestanimaltoeverinhabittheearth.realizingthatthiswhalemaygrowto100feetandweigh150tonsatmaturity,itisnotsurprisingthateachonedevoursmorethanoonofkrilldaily.