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1、Unit2WorkingthelandUsingLanguageReadingCHEMICALORORGANICFARMING?Overthepasthalfcentury,usingchemicalfertilizershasbecomeverycommoninfarming.Manyfarmerswelcomedthemasagreatwaytostopcropdiseaseandincreaseproduction.Recently,however,scientistshavebeenfindingthatlong-termuseofthesefertilizers
2、cancausedamagetothelandand,evenmoredangerous,topeople’shealth.Whataresomeoftheproblemscausedbychemicalfertilizers?First,theydamagethelandbykillingthehelpfulbacteriaandpestsaswellastheharmfulones.Chemicalsalsostayinthegroundandundergroundwaterforalongtime.Thisaffectscropsand,therefore,anim
3、alsandhumans,sincechemicalsgetinsidethecropsandcannotjustbewashedoff.Thesechemicalsinthefoodsupplybuildupinpeople’sbodiesovertime.Manyofthesechemicalscanleadtocancerorotherillnesses.Inaddition,fruit,vegetablesandotherfoodgrownwithchemicalfertilizersusuallygrowtoofasttobefullofmuchnutritio
4、n.Theymaylookbeautiful,butinsidethereisusuallymorewaterthanvitaminsandminerals.Withthesediscoveries,somefarmersandmanycustomersarebeginningtoturntoorganicfarming.Organicfarmingissimplyfarmingwithoutusinganychemicals.Theyfocusonkeepingtheirsoilrichandfreeofdisease.Ahealthysoilreducesdiseas
5、eandhelpscropsgrowstrongandhealthy.Organicfarmers,therefore,oftenpreferusingnaturalwastefromanimalsasfertilizer.Theyfeelthatthismakesthesoilintheirfieldsricherinmineralsandsomorefertile.Thisalsokeepstheair,soil,waterandcropsfreefromchemicals.Organicfarmersalsousemanyothermethodstokeepthes
6、oilfertile.Theyoftenchangethekindofcropineachfieldeveryfewyears,forexample,growingcornorwheatandthenthenextyearpeasorsoybeans.Cropssuchaspeasorsoybeansputimportantmineralsbackintothesoil,makingitreadyforcropssuchaswheatorcornthatneedrichandfertilesoil.Organicfarmersalsoplantcropstousediff
7、erentlevelsofsoil,forexample,plantingpeanutsthatusetheground’ssurfacefollowedbyvegetablesthatputdowndeeproots.Someorganicfarmerspreferplantinggrassbetweencropstopreventwindorwaterfromcarryingawaythesoil,andthenleavingitinthegroundtobecomeanaturalfertilizerforthenext
