更新时间：2025-08-07 14:28:34
scatteredthroughtheseasoftheworldarebillionsoftonsofsmallplantsandanimalscalledplankton.mostoftheseplantsandanimalsaretoosmallforthehumaneyetosee.theydriftaboutlazilywiththecurrents,providingabasicfoodformanylargeranimals.planktonhasbeendescribedastheequivalentofthegrassesthatgrowonthedrylandcontinents,andthecomparisonisanappropriateone.
inpotentialfoodvalue,however,planktonfaroutweighsthatofthelandgrasses.onescientisthasestimatedthatwhilegrassesoftheworldproduceabout49billiontonsofvaluablecarbohydrateseachyear,thesea＇splanktongeneratesmorethantwiceasmuch.despiteitsenormousfoodpotential,littleeffectwasmadeuntilrecentlytofarmplanktonaswefarmgrassesonland.nowmarinescientistshaveatlastbeguntostudythispossibility,especiallyasthesea＇sresourcesloomevenmoreimportantasameansoffeedinganexpandingworldpopulation.nooneyethasseriouslysuggestedthat"plankton-burgers"maysoonbecomepopulararoundtheworld.asapossiblefarmedsupplementaryfoodsource,however,planktonisgainingconsiderableinterestamongmarinescientists.onetypeofplanktonthatseemstohavegreatharvestpossibilitiesisatinyshrimp-likecreaturecalledkrill.growingtotwoorthreeincheslong,krillprovidesthemajorfoodforthegreatbluewhale,thelargestanimaltoeverinhabittheearth.realizingthatthiswhalemaygrowto100feetandweigh150tonsatmaturity,itisnotsurprisingthateachonedevoursmorethanonetonofkrilldaily.
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