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1、Beforeanyonecanhonestlycarehowimportantitistoprotectmarinehabitats（生j舌坯：境）,oneneedstoappreciatethevastquantitiesofmarinelifethatexistsintheocean.Itishardforsomepeopletorelatetosomethingtheyneversee.However,itmakessensethatthevastexpanseofwateranditsinhabitants,covering70%oftheplane
2、t,affectsusall.距离2012年6月四六级考试越來越近，现在正是四六级考生复习冲刺的黄金时期。为了助大家取得好成绩，新东方在线四六级频道为考生网罗了四六级辅导名师，整合了各题型备考资料，给你一站式学习体验。［马上进入2042年6月四六级备考专题：英语四级复习备考英语六级复习备考免费在线模考］Mostmarineanimalsarefoundnearcoralreefs.Thesecolorfulunderwaterforestsnaturallyspringtomindwiththementionofscuba（?K中口乎吸器）divingoru
3、nderwaterlife.Coralreefsareconstructedbylivingplantsandanimals,primarilycoralsthatsurroundtheirsmallanemone（海葵）Jiketentaclesinahardskeletonthatformsmuchofthereefstructure・Theygenerallyoccurinclear,tropicalorsemi-tropicalseastoadepthofapproximately100meters（328feet）.Coralreefsfringe
4、approximatelyonesixthoftheworld'scoastlinesandarethebiologicallyrichestofallshallow-watermarineecosystems・Theysupportasmanyas1millionspeciesofanimalsandplants,butonlyasmallfractionhavebeendescribed・Amongthebestknowngroupsareatleast5,000speciesoffish,over10,000speciesofmollusk（软体动物）
5、andmorethan800speciesofreef-buildingcorals.Coralsarenotonlyimportanttofish.Reefsareimportanttothehumanpopulationforawidevarietyorreasons:forone,theyareafoodsource.Amajorityofpeoplemaketheirlivingfishingnearcoralreefsandanevenlargerpartofpopulationenjoyseatingsomeofthecatch・Unfortun
6、ately,ifcurrenttrendsofover-fishingcontinue,andwedepletefisheriesasfastasweare,thenthisfoodsourcewilleventuallyrunout.Scientificevideneeshowsthat90%oftoppredatorsintheoceanarenowextinctbecauseofover-fishing-predatoiyfishincludeanythingsalmonsizedandaboveallthewaythroughsharks.Onthe
7、otherhand,killingoffthegrazingspeciesoffishatreefsallowsalgaetobuildup,whichinturnkillsthecoral.With30%ofoceanicfishmakingtheirhomenearcoralreefsatonetimeoranother,reefsareessentialinmaintainingahealthyfishpopulationandmanyofthefishmaintainthecoralinreturn.Sustainablefishingisamust
8、.Coralsaren'tonlyafoodsour
