【InSouthAmericatherichsoiloftheAmazonRiverbasin（流域）inBrazilisknownas“blackgold”.Scientistsfoundthatthesecretofthisrichsoilwascharcoal（木炭）.Localpeoplemadeitfromanimalbonesandtreebranche】

　　InSouthAmericatherichsoiloftheAmazonRiverbasin（流域）inBrazilisknownas“blackgold”.Scientistsfoundthatthesecretofthisrichsoilwascharcoal（木炭）.Localpeoplemadeitfromanimalbonesandtreebranches.Theymixedthecharcoalwiththesoilabout1.500yearsago.

　　NowscientistsintheUnitedStateshavedoneamoderndemonstration.Theysaycharcoalfertilizationoffersarevolutionarywaytoimprovesoilqualityforhundredsoreventhousandsofyears.

　　MingxinGuoandhisteamatDelavareStateUniversityheatedtreeleavescornstalks（茎）smallpiecesofwoodandpoultrywasteinto“biochar”（生物碳）.TheyreportedtheirfindingsatarecentmeetingoftheAmericanChemicalSocietyinNewOrleans.

　　Biocharcouldbegoodnewsforfarmerswithpoorsoilandhungrypopulationstofeed.ProfessorGuosaysitcouldevenhelpagainstglobalwarming.Intensive（集约的）farmingandoveruseofchemicalfertilizergiveoutcarbondioxideintotheatmosphere.Biochardoestheoppositehesays.Ittrapscarbonintheground.

　　Theresearchersplantedwinterwheatincontainersofsoilinagreenhouse—somewithbiocharsomewithout.ProfessorGuosaysthewheatgrowsmuchbetterinthepotswithbiochar.Thesoilwasaddedtwopercentcharcoalto.Buthesaysevenaonepercenttreatmentwillincreaseproductivity.

　　Theresultsdemonstratedthatbiocharcanincreaseorganicmatterinsoil.Lossofnutrientsinsoilisanincreasingproblemworldwideasfarmerstrytogrowmorefoodforgrowingpopulations.

　　Nexttheteamwillcarryoutafive-yearstudyofbiocharwithspinach（菠菜）greenpeppersandtomatoes.

　　MingxinGuosayshelearnsaboutthe“blackgold”inBrazilfromamagazinestory.HeexplainsthatitwasdiscoveredinthejungleintheareawherewatersflowtotheAmazoninthe1960’s.Butitwasnotuntilrecentyearsthatscientistsbegantobringpublicattentiontoit.

　　小题1:AccordingtothepassagewhichofthefollowingstatementsisTRUE?A．Theresearcherswillgoonprovingtheirtheory.B．Theleadingresearcherlearnsthetheoryfromthemagazine.C．Charcoalwasdiscovered1500yearsago.D．Commonfarmingcanproducemorecarbondioxide.