简介：Background:Nationalforestresourceassessmentsandmonitoring,commonlyknownasNationalForestInventories(NFI’s),constituteanimportantnationalinformationinfrastructureinmanycountries.Methods:ThisstudypresentsdetailsaboutdevelopmentsoftheNFIinChina,includingsamplingandplotdesign,andtheusesofalternativedatasources,andspecifically·reviewstheevolutionofthenationalforestinventoryinChinathroughthe20thand21stcenturies,withsomereferencetoEuropeandtheUS;·highlightstheemergenceofsomecommoninternationalthemes:consistencyofmeasurement;moreefficientsamplingdesigns;implementationofimprovedtechnology;expansionofthevariablesmonitored;scientifictransparency;·presentsanexampleofhowChina’sexpandingNFIexemplifiestheseglobaltrends.Results:MainresultsandimportantchangesinChina’sNFIaredocumented,bothtosupportcontinuedtrendanalysisandtoprovidedatauserswithhistoricalperspective.Conclusions:NewtechnologiesanddataneedsensurethattheChineseNFI,likethenationalinventoriesinothercountries,willcontinuetoevolve.Withinthecontextofhistoricalchangeandcurrentconditions,likelydirectionsforthisevolutionaresuggested.

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简介：AchangeintheEuropeanUnionenergypolicyhasmarkedlypromotedtheexpansionofbiogasproduction.Consequently,largeamountsofnutrient-richresiduesarebeingusedasorganicfertilizers.Inthisstudy,apotexperimentwasconductedtosimulatethehigh-risksituationofenhancedgreenhousegas(GHG)emissionsfollowingorganicfertilizerapplicationinenergymaizecultivation.WehypothesizedthatcattleslurryapplicationenhancedCO_2andN_2Ofluxescomparedtobiogasdigestatebecauseoftheoverallhighercarbon(C)andnitrogen(N)input,andthathigherlevelsofCO_2andN_2OemissionscouldbeexpectedbyincreasingsoilorganicC(SOC)andNcontents.Biogasdigestateandcattleslurry,atarateof150kgNH_4~+-Nha~(-1),wereincorporatedinto3soiltypeswithlow,medium,andhighSOCcontents(Cambisol,MollicGleysol,andSapricHistosol,termedClow,Cmedium,andChigh,respectively).TheGHGexchange(CO_2,CH_4,andN_2O)wasmeasuredon5replicatesoveraperiodof22dusingtheclosedchambertechnique.TheapplicationofcattleslurryresultedinsignificantlyhigherCO_2andN_2Ofluxescomparedtotheapplicationofbiogasdigestate.NodifferenceswereobservedinCH_4exchange,whichwasclosetozeroforalltreatments.SignificantlyhigherCO_2emissionswereobservedinChighcomparedtotheothertwosoiltypes,whereasthehighestN_2OemissionswereobservedinCmedium.Thus,theresultsdemonstratetheimportanceofsoiltype-adaptedfertilizationwithrespecttochangingsoilphysicalandenvironmentalconditions.

简介：Background:Mostcurrentapproachesinforestscienceandpracticerequireinformationaboutstructureandgrowthofindividualtreesratherthan-orinadditionto-sumandmeanvaluesofgrowthandyieldatforeststandlevelasprovidedbyclassicexperimentaldesigns.Byinventingthewheeldesign,Nelderprovidedthepossibilitytoturntotheindividualtreeasbasicinformationunit.Suchtrialsprovidevaluableinsightsintothedependencyofgrowthonstanddensityatparticularsites.Methods:Here,wepresentanextensionoftheoriginaldesignandevaluationbyNelder.(i)WeestablishedNelderwheelsalonganenvironmentalgradientthroughEuropeinatlanticclimateinBelgiumandGermany,MediterraneanclimateinItaly,continentalclimateinHungaryaswellasonhighlandclimateinMexico.SuchdisjunctNelderwheelsalonganenvironmentalgradientcanberegardedandanalysedasatwo-factordesignwiththefactorsofsiteconditionandstanddensity.(ii)WepresentanadvancedstatisticalapproachtoevaluatedensitydependentgrowthdynamicsoftreesplantedinformoftheNelderdesign,whichconsidersspatio-temporalautocorrelation.(iii)Weprovetheusefulnessofthemethodsinimprovingecologicaltheoryconcerningdensityrelatedproductivity,trade-offsbetweenfacilitationandcompetition,andallometricrelationsbetweensizevariables.Results:FirstevaluationsbasedonremeasuredNelderwheelsinoak(QuercusroburL.)showasizegrowthdifferentiationduringthefirstobservationperiod.Inparticular,heightgrowthisacceleratedunderhighercompetitionindicatingfacilitationeffects.Wedetectfurthermoreahighvariabilityinallometricrelations.Conclusions:Theproposeddesign,methods,andresultsarediscussedregardingtheirimpactonforestpractice,modelbuilding,andecologicaltheory.WeconcludethattheextendedNelderapproachishighlyefficientinprovidingcurrentlylackingindividualtreelevelinformation.