Mostforestfiresarecausedbyhumancarelessnessnegligenceorignorance.Forestfirepreventionthereforeismainlyaproblemofcreatingabetterunderstandingoftheimportanceofforestsanawarenessofthedangeroffireinthewoodsandasenseofpersonalresponsibilitytosafeguardtheforestsfromdanger.Thisisnotaneasyjob.Acitydwellerusedtopavedstreetdoesnoteasilychangehissmokinghabitswhenhegoesintothewoods.

Carelesssmokersareresponsibleforthousandsofforestfireseachyear.Manyofthesearestartedwhencigarettebuttsandmatchesaretossedfromautomobiles.Othersarecausedbyhuntershikersfishermenorwoodsworkerswhoarecarelessindisposingoftheirsmokingmaterial.TheForestServicehaspostedrulesinmanyoftheNationalForeststhatprohibitsmokingexceptincertaindesignatedareas.Manyofthestateshavelawsagainstthrowinglightedmaterialsfromautomobiles.Thepreventionofsmoker-causedfireshoweverdependsuponchangingtheattitudesandbehaviorofmillionsofpeoplewhosmokeinhazardousarea.

Themostimportantnaturalcauseoffireislightning.Thisaccountsfor11percentofforestfiresonprotectedlandfortheentirenation.Inthewesternstateslightningcausesamuchhigherpercentageoffirethanitdoesintheeast.

Advancesinknowledgeoffireweatherarehelpingforestprotectionforcestoknowwhentobealertforlightning-causedfires.Adequateandwell-equippedforcescancontrolthemquicklyandholdthedamagetoaminimum.Experimentsin“seeding”thundercloudstopreventorcontrolthelightningitselfhavebeeninprocessformanyyearsbutnewbreakthroughsareneededforanysignificantreductioninthelightningstarts.

1.Thepassageischieflyabout

A.smokinginforests

B.thechiefcauseofforestfireandtheirprevention

C.changingtheattitudesandbehaviorofmillionsofpeople

D.advancesinknowledgeoffireweather

2.Preventingsmoker-causedforestfiresismainlyaproblemof——.

A.buildingtheproperknowledgeandhabitsinhumanbeings

B.safeguardingtheforestfromfire

C.postingrulesinforests

D.holdingthedamagetominimum

3.Lightning-causedfiresc