Canoco软件操作的简单教程步骤：1．打开excel文档，如下图所示，包含环境变量（12个）和生物因子（15种C源利用性）。共是8个处理，每个处理三个重复，总共是24个土壤样品。Potential:potentiallymineralizableorganicCpools;SOC,solubleorganicCextractedby2MKCl;SON,solubleorganicNextractedby2MKCl;soilmoisturecontent;TC,TotalC;TN,TotalN;WHC,waterholdingcapacity;MBC,microbialbiomassC;MBN,MicrobialbiomassN.The15Csourceswerechosentocoverarangeoflowmolecularweightcompounds(includingcarbohydrates,aminoacidsandcarboxylicacids)thatarecommonlyinrootexudates(Campbelletal.,2008).Thenumbersfrom1to16correspondtorepresentL-alanine,L-arginine,citricacid,D-galactose,aminobutyricacid,malicacid,oxalicacid,3,4-OHbenzoicacid,L-arabinose,L-cysteine,D-fructose,D-glucose,L-lysine,N-acetylglucosamine,D-trehalose,water,respectively.?选中区域（包括前面的数字），点击复制，然后打开canoco软件中WcanoIMP，如下图所示。然后选中saveincondensedformat，然后点击save。分别保存文件为environ.dta(dta是canoco默认的样式)和species.dta.文件形式如下图。2.打开canoco软件—newproject，得到下面的界面。3．点下一步后，有三个brown窗口，前2个分别选择environ.dta和species.dta.第三个选择软件自带合适的处理方法（如CCA和RDA等）。本文是选用RDA分析。4．其他还有一些窗口，但是问题不大，这里就不多说了。直接进入下一步，点击analyze，如下图所示。完成后点击canodraw。5．点击create窗口，如下图所示。得到最后的结果。结果的解释：Therelationshipsbetweenenvironmentalfactorsandmicrobialmetabolicprofileswereasshownabove.Plotscanbeinterpretedquantitativelyusingthelengthofthearrowtoindicatehowmuchvariancewasexplainedbythatfactor;thedirectionofthearrowsforindividualenvironmentalfactorindicatinganincreasingweightingofthatfactor.Thesoilsamplearrowspointinginapproximatelythesamedirectionastheenvironmentalarrowsindicateahighpositivecorrelation(thelongerthesoilsamplearrow,thestrongertherelationship;Kennedyetal.,2004).Amongallenvironmentalfactors,C0exhibitedthegreatestinfluenceonthesoilsamples(P<0.01)followedbypHandsoilmoistureandSONcontent.Whatisdrivingchanges?PreviousstudieshavesuggestedthatRDAwasasuitablemethodforquantifytherelationshipbetweenenvironmentalfactorsandchangesinmicrobialcommunityofsoils(Kennedyetal.,2004;Macdonaldetal.,2009).Inthisstudy,wefoundthatclassifiedmicrobialmetabolicprofilesbasedoncovercroptreatmentsandquantifiedthecontributionsofeachenvironmentalfactortosoilsamples,aimingtowhichenvironmentalfactormajorlyinfluencedthechangesofmicrobialmetabolicprofilesbetweentheCKandcovercroptreatments.Recentstudieshaveshownthesoilmicrobialmetabolicprofilesisstronglyaffectedbyabioticenvironmentalfactors,suchasSoiltotalC(Degensetal.,2000),SOC(Huangetal.,2008)andC:Nratio(GrahamandHaynes,2005).However,wefoundthatC0，ratherthanotherenvironmentalfactors,wasmoreindicativeofthechangeofmicrobialmetabolicprofiles.相关的文献：Degens,B.P.,Schipper,L.A.,Sparling,G.P.,Vojvodic-Vukovic,M.2000.DecreasesinorganicCreservesinsoilscanreducethecatabolicdiversityofsoilmicrobialcommunities.SoilBiol.Biochem.32,189-196.Graham,M.H.,Haynes,R.J.2005.CatabolicdiversityofsoilmicrobialcommunitiesundersugarcaneandotherlandusesestimatedbyBiologandsubstrate-inducedrespirationmethods.Appl.SoilEcol.29,155-164.Huang,Z.Q.,Xu,Z.H.,Chen,C.R.2008.Effectofmulchingonlabilesoilorganicmatterpools,microbialcommunityfunctionaldiversityandnitrogentransformationsintwohardwoodplantationsofsubtropicalAustralia.Appl.SoilEcol.40,229-239.Sissoko,A.,Kpomblekou-A,K.2009.Carbondecompositioninbroilerlitter-amendedsoils.SoilBiol.Biochem.doi:10.1016/j.soilbio.2009.10.007.Kennedy,N.,Brodie,E.,Connolly,J.,Clipson,N.2004.Impactoflime,nitrogenandplantspeciesonbacterialcommunitystructureingrasslandmicrocosms.Environ.Microbiol.6,1070-1080.Macdonald,C.A.,Thomas,N.,Robinson,L.,Tate,K.R.,Ross,D.J.,Dando,J.,Singh,B.K.2009.Physiological,biochemicalandmolecularresponsesofthesoilmicrobialcommunityafterafforestationofpastureswithPinusradiata.SoilBiol.Biochem.41,1642-1651.
