feedtheworldoldedition课件
日期：2010-07-04 07:47
thatishalftheworld’sworkers，000yearsago，In1994，ProfessorPimentelofCornellUniversitywarnedofthefollowingproblemsinprovidingenoughfoodfortheworld’sgrowingpopulation:By2100thepopulationwillbe12-15billion，intheMiddleEastandinIndiaTodayfarmingemploysmorepeoplethananyothertypeofworkItisthoughtthatonemillionpeople，whenpeoplebegantogrowcropsintherivervalleysoftheNileinEgypt，orseventimesitssustainable(足可支撑的，)levelFarmersareabandoning(遗弃)25millionacres(英亩)eachyearbecauseofsoillossorwaterlogging(水浸)Thedeclining(衰退中的)fertility(肥沃)ofthesoilwilllowerfoodproductionby20%inthenext25yearsTopsoil(表层土)isbeinglost40timesfasterthanitcanbereplacedCroplossesdestroyedbypestshaveincreasedfourtimesinthelast50years（1）Whendidtheagriculturestart?（2）WhyaretheChinesepeoplemakinggreateffortstoprotecttheirfarmland?（3）Whatisabigproblemintheworldtoday?（4）Howmanypeoplestarvetodeatheveryyear?ReadingAgriculturefirststartedabout10，earntheirlivingbyfarmingTheproblemishowtofeedagrowingworldpop，
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