摘要
Fir(Abiesfaxoniana)distributeswidelyinthealpineandsubalpineregionofwesternSichuan.Tounderstandeffectsoffreeze-thaweventsonsoilmicrobialcommunity,microbialnumberwasinvestigatedmonthlyinafirforest,employingthemethodoflabfreeze/thawcyclesincombinationwithfieldsoilsampling.Bacterialandactinomycetenumberinsoildecreasedandfungalcountincreasedafteraseasonalfreeze-thawseasoncycle.Bacterialandfungalcountsincreasedwiththedecreasedaltitude,whileactinomycetecountdecreasedwiththedecreasedaltitude.Differentmicrobeshadvariouschangepatternswithaltitudeinhumuslayer(AL),illuviallayer(BL)andparentmateriallayer(CL).Comparedwiththe3582maltitude,bacterialcountintheALandCLatthe3298maltitudeincreased4.2%and7.0%,respectively,butthatintheBLdecreased0.6%.Meanwhile,bacterialcountincreased11.5%,3.5%and2.1%intheAL,BLandCLatthe3023maltitudeincomparisonwiththe3298maltitude,respectively.FungicountintheAL,BLandCLincreasedby10.5%,10.3%and16.4%atthe3298maltitudeincomparisonwith3582maltitude,respectively,whileitincreasedby2.4%,1.7%and3.5%atthe3023maltitudeincomparisonwith3298maltitude,respectively.ActinomycetecountintheALatthe3298maltitudeincreasedby0.7%thanthatatthe3582maltitude,butdecreased5.9%and13.9%intheBLandCL.IntheALandBL,itincreased5.2%and5.2%respectivelyatthe3023maltitudethanthatatthe3298maltitude,whileintheCLitdecreased12.4%.Theseresultswereinagreementwiththesimulationfreeze/thawcycleexperimentinlab.Theresultsalsorevealedthattheseasonalfreeze-thawcycleincreasedtheratioofsoilfungitobacteria.Theseresultsdemonstratedthatdifferentmicrobialgroupsrespondeddifferentiallytotheseasonalfreeze-thawcycle,whichmaybeanimportantecologicalmechanismformaintainingtheseasonalfrozenecosystem.
出版日期
2012年03月13日（中国Betway体育网页登陆平台首次上网日期，不代表论文的发表时间）
