YI.阅读理解(2015•江西)Todaytherearemanymorefiresthaninthepast.Over100000wildfiresburneachyearinAmerica.Russiahas20000to35000wildfireseveryyear.Australiahasonaverage60000eachyear.TheseHresdestroy(损
YI.阅读理解(2015•江西)Todaytherearemanymorefiresthaninthepast. Over100000wildfiresburneachyearinAmerica.Russiahas20000to35000wildfireseveryyear.Australiahasonaverage60000eachyear.TheseHresdestroy(损害)hugeareasofforestsandburnhundredsofhomes.
Manyexpertsbelievethereareseveralreasonsforthissuddenincreaseinfires.Thefirstreasonisclimate(气候)change.Recentweatherhasbeenwarmeranddrier.Thisleadstodangerousfireconditions.Whenlightningstrikes(发生雷电)，drygrasseasilycatchesfire.Hotwindsaddtotheproblem.Thewindspreadsafirequickly.In2010Russiahadthehottestanddriestsummerinacentury. Injustonemonth500firesdestroyedover2000homes.Somepeoplelosttheirlives.
Traditionalfire-fightingpracticesareanotherreasonfortheincreaseinfires.InAmericafirefightersusedtoquicklyputouteveryfire.Theydidn'tallowthegrassandtreestoburn.Asaresulttodaymanyforestshavethickervegetation(植被). Thickervegetationmeansmorefuel(燃料)forfires. Alsowithoutfiresfromtimetotimeforestsbecomeovercrowdedandunhealthy.Sometreesaredead.Thedeadwoodtheneasilycatchesfire.SosurprisinglyAmericahasmanymorefirestodaypartlybecauseofitspastfire-fightingpractices.
Scientistsnowunderstandthatafirecanbeanaturalpartofahealthyforest.AsaresultcountrieslikeAustraliaallowmorefirestoburnnaturally. Sometimesfirefightersevenstartfirestogetridof(去除)deadwood.Ofcoursetheycarefullycontrolthefires. Thefirethinsoutoldtrees.Thisallowssunlighttoreachtheground.Asaresultfireshelpnewtreestogrow. Thereforeifafireisnotaserious threat(威胁)topeoplefirefightersmayletitburnnaturally.
1.WhydidRussiahavesomanyfiresinonemonthin2010?
A.Becauselightningspreadthefire.
B.Becausetherewasmuchfuelforfires.
C.Becausetherewerenotenoughfirefighters.
D.Becauseitwasunusuallyhotdryandwindy.
2.WhathappensbecauseofthetraditionalfirefightingpracticesintheUSA?
A.Therearefewerwildfires.
B.Treesandgrassbecomethicker.
C.Theweatherbecomeswarmeranddrier.
D.Sunl