[1]cause and effect

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1、WritingCauseandEffectCausesofDeforestationTherearemanydifferentforestsintheworld,includingwoodlandsandtropicalrainforests,andpeoplehavebeenclearingtheseareasforcenturies.Mostrecently,thepermanentdestructionofforestsandwoodlands,knownasdeforestation,hasbeenrecognizedasaglobalproblem

2、.Today,morethanhalftheEarth’soriginalrainforestsaregone,andatthecurrentrateofdestruction,rainforestscoulddisappearcompletelywithin100years.Deforestationnowoccursinareasthatpreviouslyremaineduntouchedbecausemoderntransportationandequipmentallowpeopletoexploitthoseareasmoreeasily.Whi

3、lethereareseveralreasonsfordeforestation,twoimportantcausesarerelatedtothisexploitation:clearingthelandforagriculturalpurposesandcommerciallogging.Peopleoftendestroytreesinordertoopenuplandforagriculturaluse.Theyclearforestareasforagriculturebecausetheyneedtofeedthemselvesorbecause

4、theywanttoproducecashcrops.Somepeople,suchaspoorerfarmers,chopdowntreesinsmallareassothattheyplantcropstosustainthemselvesandtheirfamilies.Otherpeopleclearforestareasonalargerscale,fortheywanttoearnmoney.Insomecasestheclearedforestareasbecomecattleranches.Inothercasespeoplemightgro

5、wrubberorcoffeeplantsonthesedeforestedareas.Inalloftheselarger-scalecases,theforestisclearedbecauseofaneedordesiretoearnmoneythroughthesaleofproductssuchasbeef,rubber,coffee,andothercropsthatareproducedontheland.However,thesoilisoftentoopoortosupportthecropsthatareplantedinthesecle

6、aredhumidtropicalareas.Sincethesefarmersandranchersareseekinglandtosatisfytheiragriculturalneeds,theymovetonewareasandclearmoreforests.Becauseofthismovement,thedeforestationmayincreaserapidly.Anotherimportantcauseofdeforestationiscommerciallogging.Becauseofthelargeinternationaldema

7、ndfortimberandtheinternationaltradethathasdevelopedfromthisdemand,commerciallogginghasbecomeabigbusiness.Sinceboththedemandforwoodanditsproductandthewood-processingindustryhavegrown,therateofforestlosshasincreasedaswell.Treesarecutsaleastimber,orthewoodmaybeusedtomakepaperorotherpr

8、oductssuchasfurniture.Grow