简介：Invarioustemperatures,theeffectsofinorganicacidsonthefreephenollevelinliquefactionproductswereinvestigated.Inthispaper,thefreephenollevelwasusedasanindicatortoevaluateliquefactionefficiency.Resultsshowedthatsulfuricacidwasthebestamongthe4acids.Undertheconditionofreactiontemperature150oC,reactiontime1.5h,liquefactionratio(liquid/particleboard)4andcontentofsulfuricacid6%,thefreephenollevelintheliquefactionproductsofwasteparticleboardis36.95%,andthatoforiginalparticleboardis24.27%.

简介：Canada'sborealforestrepresentsanimportantcontributoroftheworld'swoodsupplyindustry.However,maintainingorincreasingproductivityoftheborealforestmaybechallenginginareasdominatedbyforestedpeatlands.Moreover,sustainablemanagementoftheseforestsmustalsoconsiderotherimportantaspectsoftheforestecosystemsuchasbiodiversityandcarbonsequestration.Toaddresstheseconcerns,ecosystem-basedmanagementhasbeenimplementedinsomeCanadianjurisdictions,suchasinregionswherealargeportionoftheborealforestisdominatedbyforestedpeatlands.Theobjectivesofthispaperare(1)tosummarizeourcurrentunderstandingofhownaturaldisturbancesinfluencestanddynamicsandbiodiversityinforestedpeatlands,and(2)toreviewthemaindifferencesbetweennaturalandmanagedforeststandswithrespecttosoil.properties,standproductivity,understoryplantcommunities.Wealsodiscusshoweven-agemanagementregimesucceedsorfailstopreserveoldforestsandhowthislossaffectsbothforeststructureandhabitatdiversityatthelandscapelevel.Weconcludebyshowinghow,inborealforestedpeatlands,forestmanagementcouldcontributetocarbonsequestrationandmitigateprojectedclimatechange.

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简介：Nonlinearmixedeffectsmodel(NLMEM)isbuiltontherelationshipofthefixedandrandomeffectsintheregressionfunction.TheNLMEMhasanobviouscomparativeadvantageinanalyzingthelongitudinaldata,repeatedmeasuresdataandmultileveldata.Two-levelNLMEMisusedtoanalyzethedominantheightforChinesefir(Cunninghamialanceolata).Theauthorsoutlinethetwo-levelNLMEMandintroducetheparametersestimationmethodofthemodel.BasedonfivecommonRichardandLogisticmodels,themixedmodelisbuilt.Themodelingdataareusedtocalculateandcomparewith19modelsderivedfromeachbasedmodel,and5optimalmixedmodelsarebuilt.Comparedthe5optimalmixedmodelswithtraditionalregressionmodels,itisshowedthatthetwo-levelNLMEMhasabetterfittingeffectthantheregressionmodel.

简介：Basedonamultilevellinearmixedmodelapproach,anindividualdiameterincrementmodelwasdevelopedforfirplantationtreesgrowinginJiangxiProvince.Thedatasetusedinthisstudycamefromlong-termpermanentresearchplots.Thedatabaseconsistsoftotalof82counties,365plots,5416treesand16248observations.Thepaperchosemixedeffectsmodelsinsteadofregressionanalysisapproachbecauseitallowsforpropertreatmentoferrortermsandcorrelationinarepeatedmeasuresanalysisframework.Themodelwasdefinedasamixedlinearmodelwithparameterrandomeffectofplot,areaorplotandareasimultaneous.Inadditiontheheteroscedasticityandcorrelationwastakenintoaccount.Mixedmodelcalibrationofdiameterincrementwascarriedoutwiththeindependentdatausingadifferentsampleofcomplementaryobservations.Theresultshowedthatthetotalstandbasalarea,thediameteroftargettrees,theratioofbasalareaoflargertreestotargettreediameter,andaltitudewerefoundtobesignificantpredictors.Boththefittingmodelandthecalibratedmodelmeanasubstantialimprovementcomparedwiththeclassicalapproachwidelyusedinforestmanagement.Aftertakingintoaccountreasonablevariancefunctionofheteroscedasticityandcorrelation,themodelshowsbetterofgoodnessoffitthanonlytakingintoaccountparameterrandomeffects.Thistypeofmodelingmethodologyshowsflexible,preciseandaccurate.