Onereactiontoalltheconcernabouttropicaldeforestation(砍伐森林)isablankstarethatasksthequestion"SinceIdon'tlivetherewhatdoesithavetodowithme?"Theansweristhatyourwayofl

　　Onereactiontoalltheconcernabouttropicaldeforestation(砍伐森林)isablankstarethatasksthequestion"SinceIdon'tlivetherewhatdoesithavetodowithme?"

　　Theansweristhatyourwayoflifewhereveryouliveintheworldistiedtothetropics(热带地区)inmanyways.Ifyouliveinahousewashyourhaireatfruitsandvegetablesdrinksodaordriveacaryoucanbecertainthatyouareaffectedbythelossoftropicalforests.

　　Biologicallywearelosingtherichestregionsonearthwheneachminuteapieceoftropicalforestthesizeoftencityblocksdisappears.Asmanyasfivemillionspeciesofplantsanimalsandinsects(40to50percentofalllivingthings)livethereandarebeinglostfasterthantheycanbefoundanddescribed.Theirlossisimmeasurable.

　　Takerubberforexample.Formanyusesonlynaturalrubberfromtreeswilldo.Syntheticsarenotgoodenough.Todayoverhalftheworld'scommercialrubberisproducedinMalaysiaandIndonesiawhiletheAmazon'srubberindustryproducesmuchoftheworld'sfourmilliontons.Andrubberisanimportantmaterialinmakingglovesballoonsfootwearandmanysportinggoods.Thousandsofothertropicalplantsarevaluablefortheirindustrialuse.

　　Manyscientistsstronglybelievethatdeforestationcontributestothegreenhouseeffect–orheatingoftheearthfromincreasedcarbondioxideintheatmosphere.Aswedestroyforestswelosetheirabilitytochangecarbondioxideintooxygen.

　　Carbondioxidelevelscoulddoublewithinthenexthalf-centurywarmingtheearthbyasmuchas4.5degrees.TheresultApartialmelt-downofpolaricecapsraisingsealevelsasmuchas24feet;even15feetcouldthreatenanyonelivingwithin35milesofthecoast.Unbelievable?Maybe.Butscientistswarnthatbythetimewerealizethesevereeffectsoftropicaldeforestationitwillbe20yearstoolate.

　　Cantropicaldeforestationaffectoureverydaylives?Nowyoushouldhavegottheanswer.

　　68.Theunderlinedword"synthetics"inParagraph4probablymeans .

　　A.naturalrubber B.tropicalmaterials

　　C.man-madematerial D.commercialrubber

　　69.Inthelastparagraphtheauthortriesto .