简介:Background:Soilorganiccarbon(SOC)isalargereservoirofterrestrialcarbon(C);itconsistsofdifferentfractionsofvaryingcomplexityandstability.PartitioningSOCintodifferentpoolsofdecomposabilityhelpbetterpredictthetrendofchangesinSOCdynamicsunderclimatechange.InformationonhowphysicalfractionsandchemicalstructuresofSOCarerelatedtoclimateandvegetationtypesisessentialforspatialmodelingofSOCprocessesandresponsestoglobalchangefactors.Method:Soilsampleswerecolectedfrommultiplerepresentativeforestsitesofthreecontrastingclimaticzones(i.e.cooltemperate,warmtemperate,andsubtropical)ineasternChina.MeasurementsweremadeonSOCcontentsandphysicalfractionsofthe0–20cmsoillayer,andthechemicalcompositionofSOCofthe0–5cmsoillayer,alongwithmeasurementsandcompilationofthebasicsiteandforeststandvariables.Thelong-termeffectsoftemperature,litterinputs,soilcharacteristicsandvegetationtypeontheSOCcontentsandfactionswereexaminedbymeansof"spacefortimesubstitution"approachandstatisticalanalysis.Result:Meanannualtemperature(MAT)variedfrom2.1℃atthecooltemperatesitesto20.8℃atthesubtropicalsites.TotalSOCofthe0–20cmsoillayerdecreasedwithincreasingMAT,rangingfrom89.2g·kg^-1incooltemperateforeststo57.7g·kg^-1insubtropicalforests,atanaveragerateof1.87%reductioninSOCwitha1℃increaseinMAT.WithincreasingMAT,theproportionsofaromaticCandphenolicCdisplayedatendencyofdecreases,whereastheproportionofalkylCandA/O-Avalue(theratioofalkylCtothesumofO-alkylCandacetalC)displayedatendencyofincreases.Overall,therewerenosignificantchangeswithMATandforesttypeineitherthephysicalfractionsorthechemicalcomposition.BasedontherelationshipbetweentheSOCcontentandMAT,weestimatethatSOCinthetop20soillayerofforestspotentiallycontribute6.58–26.3PgCgloballytotheat
简介:Becauseofthedistinctionofsoilpropertyandhumuscontent,soilwatercontentisnotidealtoindicatewhetheritissuitabletothegrowthofplant.MainlybasedonthePF-anumericalvaluedenotingthewaterregimeofsoilandconnectedwiththegrowthofplant,thestudycombinedthemoisturepercentageofsoilwithPFtoresearchinquantitytheinterrelationbetweenthemoisturepercentageandPFindifferentsuccessionphasesofsubalpinedarkconiferousforestinGonggaMountain.Theresultsshowedthat:(1)InthesamePFvalue,themoisturepercentageinhumushorizonincreasedgraduallywiththedevelopmentofthesuccessionofthedarkconiferousforest;Themoisturepercentageofover-matureforestwasthehighestand>matureforest>half-matureforest>younggrowthforest;(2)Withtheincreaseofsoildepth,thesoilbulkdensityincreasedandthemoisturepercentagedecreased,butthedifferenceinthepercentageofmoisturewasnotnotableindifferentsuccessionphases.(3)Indifferentsuccessionseries,thevegetationaffectedthesoilwatercharacteristicsbyincreasingthesoilorganicmatter,improvingthesoilconstruction,recedingthesoilbulkdensityandenhancingthesoilporosity;(4)Thehumushorizonofthedarkconiferousforestsoilhasthehighestwaterholdingcapabilityinthisregion.
简介:描述的这篇论文主要理想的四个基本模型作为Kunlunshan模型,在山Lushan国家公园美化Xumishan模型,基督教徒桃树花陆地模型,模型。在有象东方山谷的东方格罗夫庙,白鹿洞学院,简洁和宁静庙宇,Lushan山谷,和别墅簇一样的理想的风景特征的山Lushan的五个典型地方被分析,并且为每个地方的基本模型的集成被讨论让现实主义的风景遵循理想的需要。而且,讨论也包含了在资源,文化,结构,函数,进程,规模和区域被展示的理想的风景的特征。在结论,在山Lushan国家公园的理想的风景是在人和自然之间的相互作用的产品。山Lushan与超过1000年的历史继承中国传统的文化的本质;并且它也在不同文化之中和冲突和改编象在自然和人文学科之间的交换一样吸收西方的文化的吗哪。自然风景能被生态的计划的方法对幸存需求和人类的文化味觉满意。
简介:ThispapergivesanexpatiationonsignificanceandspecificrequirementsofdevelopingafforestationandreforestationprojectunderCDMinKyotoProtocol.AccordingtotheinternationalrulesandthecurrentforestrydevelopmentsituationinChina,thepriorityareaforCDMafforestationandreforestation(CDMA/R)projectisfinallyfoundafterscientificselectionandassessmentonindicators,includingthenon-forestlandareain1990,growthrateoftree,afforestationcost,biodiversityandcommunitydevelopment.TheoutcomefromthestudyprovidesasolidbasisforfindingandimplementingCDMA/RcarbonsequestrationprojectsinChina.ThestudyalsoputsforwardsuggestionsonthestrategytodevelopandmanageCDMA/RprojectsinChina
简介:Themarketmechanismforforestecosystemservicehasalreadybecomecommonknowledgeamongcountriesintheinternationalmovementtoaddressglobalclimatechange.Inthispaper,internationalexperiencesofforestecosystemmarketsuchasbetterunderstandingofconcept,publicparticipation,soundtradingrulesandmeasurementstandardsareanalyzed,anditsimplicationforChinaisalsosummarized.Finally,theprospectsofforestecosystemservicemarketinChinaarediscussed.Thepurposeofthispaperi...
简介:Thepapercameupwiththebasicprinciples,technologysystem,planningandforestgovernancesystemofclose-to-natureandvalue-orientedforestmanagementonthebasisofdiscussionsonitsconceptandtheoreticalfoundation,andfinallyintroducedinitialeffectsofclose-to-natureandvalue-orientedforestmanagementimplementedinHarbin.
简介:Factoranalysisandexpertscoringmethodswereusedtorankflammabilityof16majorspeciesoftreesandshrubsinDaxing’anlingareaofnortheasternChina,basedon6flammabilityvariables,i.e.,airdrymoisturecontent,absolutedrymoisturecontent,ignitionpoint,ashcontent,heatofcombustionandextractivecontentmeasuredonleaves,barksandtwigs.Outof16speciesevaluated,forleaves’flammability,LarixgmeliniwasthesmallestandPinussylvestrisvar.mongolicawasthebiggest;forbarks’flammability,SalixkoreensiswasthesmallestandP.sylvestrisvar.mongolicawasthebiggest;andfortwigs’flammability,PopulusdavidianawasthesmallestandLedumpalustrevar.dilatatumwasthebiggest.Theflammabilityrankingbasedontheintegratedscoresofleaves,barksandtwigssuggestedthatPrunuspadus,Betuladahurica,andL.gmeliniwerethetop3lessflammablespeciesandthatL.palustrevar.dilatatum,P.sylvestrisvar.mongolica,andR.simsiiwerethetop3moreflammablespecies.Thisrankingagreedwellwithcurrentstandardsandexperienceandshouldhelpthespeciesselectionforbuildingfire-breakforestbeltsinthestudyregion.
简介:TheplantationoccupiesgreatproportioninurbanforestinmanycitiesinChina.Thedesignandmanagementforurbanforestsupplementseachother.Thedesigndecidestheorientationofmanagement,whilethemanagementalsoaffectsthelandscapeeffectsandecologicalbenefitsofthedesigninreverse.Therearemanyissuesondesignandmanagementofurbanforest.Forexample,somedesignsonlyemphasizethevisualimpressionwhileignoringtheecologicalbenefits,theproblemsofsimplifyingtheforestlayerstructureandpurifyingitsspeciescompositionareubiquitous,Itisshortofcomprehensiveanalysisoflocalenvironmentconditions,thephenomenaareveryoutstandinginlearningforeignorothercity'smodelbycopyingmechanically.Themanagementmodelisnotonlymonotonous,butalsobehindthestepofurbandevelopmentandthehumandemandforreturningtonature.Theseunreasonabledesignsandmanagementsareoneofthemainreasonsforlowerecologicalbenefits,andalsocausedsomeotherbadaftereffects,suchaslowerbiodiversityandhighcostofmanagement,etc.Sothethoughtofclose-to-naturedesignandmanagementinurbanforestisproposedanditsfeasibilityandmethodsarediscussedinthepaper.
简介:Abstract:FortyspeciesofBasidiomycotafrom21generain15families,collectedfromLiuxiheNationalForestPark,Guangzhou,China,havevaluesforusebylocalpeople.Morethanhalfofthespeciescollectedareedible,andsome(Lactariusdeliciosus,Boletusspp.)aregatheredforcommercialconsumptioninSouthChina.Tenspecieshavemedicinalproperties,andincludeDictyophora,Ganoderma,PisolithusandScleroderma.Over60%species(26taxa)areectomycorrhizalinvolving12ediblefungi.ThemostabundantfamiliesweretheAmanitaceae,BoletaceaeandSclerodermataceae,whichformimportantectomycorrhizalassociationswithconiferousandmixedbroad-leafedtreesinthePark.Prospectiveusesofthesemacrofungiarediscussed.
简介:AustriaandGermany,thetwoforestdevelopedcountries,havedrawnalotofexperiencesinforestmanagement.ThisarticlesummarizesthesuccessfulexperiencesofforestmanagementreforminthosetwocountiesandputsforwardpolicyrecommendationsonforestmanagementreforminChina.
简介:Chinaisoneofthelargestcountriesintheworldintermsofplantedforestsarea.Plantedforestsplayanimportantroleinsoilandwaterconservation,foodsource,timbersupplyandenergysecurity,buttherearestillmanyproblemswaitingforimmediateresolution.BasedonthecurrentdevelopmentstatusofplantedforestinChina,thepapermadeancomprehensiveanalysisforthepositiveimpactandexistingproblemswithregardtoplantedforests,andthencameupwithpolicyrecommendationsforprom...
简介:Theforestecosystemgoodsandservicesandthenaturalcapitalstocksthatproducethemmakegreatcontributiontonationaleconomyandhumanwelfarebothdirectlyandindirectly.ThispaperevaluatestheeconomicvalueofnaturalcapitalstockandtheannualoutputflowofforestecosystemgoodsandservicestakingQingdaoCityanditseightdistrictsascasestudy.Theresultsofthevaluationstudyshowed,thatthestockvalueofforestnaturalcapitalofQingdaowasRMB13.46billionattheendof2007...
简介:Fourvegetationtypes,namelyconiferousandbroadleavedmixedforest,secondarydeciduousbroadleavedforest,openshrubsandmeadow,withdwarfbamboo(Indocalamuswilsoni)arecomparedontheirfloristiccomposition,lifeform,communitystructure,andsurvivorshipofbamboos.Disturbanceofconifer-loggingtwodecadesagopromotedthespeciesdi-versity,butnegativelyinfluencedthesurvivorshipofdwarfbamboowhichisdominateontheforestfloor.Openshrubsbearmorespeciesdiversityandmoregeophytesinitslife-formspectrumthanitsbackgroundvegetationsubalpinemeadow,how-ever,dwarfbambooisgrowingmuchbetterintheopenshrubsthaninthemeadow.Itseemsdwarfbambooprobablyfavor-itestooccurinthevegetationatgentleslopeswithamediatecanopycover.Itsmassfloweringinthesecondarydeciduousforestsuggeststhatasimultaneousfloweringandfollowingdiebackmaybeirruptintherecentlycomingyearsoverthesubal-pineShennongjiainChina,whichwillbenotonlyalterthefloristiccompositionandcommunitystructureoftheoldbamboostands,butalsoinfluencethesurvivorshipofthisrarespecies.
简介:Thepaperanalyzedthebasiccharacteristicsoffast-growingandhigh-yieldplantation,classifiedandidentifiedtheecologicalproblemsinitsdevelopment,andfinallyproposedthebasicprinciplesandcorrespondingtechnicalmeasuresforfast-growingandhigh-yieldplantationecosystemmanagementbasedontheseproblems.
简介:ThiscasestudyoutlinestheproblemsfacedbythepeoplesoftheHexiCorridor.Theseproblemsareseriousandurgent,andarerepresentativeofthosefacedbyothercommunitiesrightacrosswesternChina.Therootcausesareoutlinedandsomeremediesaresuggested.ThepracticalmeasuresproposedunderChina'sNationalActionPlantoCombatDesertificationaredescribedanddiscussed.
简介:Modelingheight–diameterrelationshipsisanimportantcomponentinestimatingandpredictingforestdevelopmentunderdifferentforestmanagementscenarios.Inthispaper,tenwidelyusedcandidateheight–diametermodelswerefittedtotreeheightanddiameteratbreastheight(DBH)dataforPopuluseuphraticaOliv.withina100hapermanentplotsatArghanVillageinthelowerreachesoftheTarimRiver,XinjiangUyghurAutonomousRegionofChina.Datafrom4781treeswereusedandsplitrandomlyintotwosets:75%ofthedatawereusedtoestimatemodelparameters(modelcalibration),andtheremainingdata(25%)werereservedformodelvalidation.Allmodelperformanceswereevaluatedandcomparedbymeansofmultiplemodelperformancecriteriasuchasasymptotict-statisticsofmodelparameters,standardizedresidualsagainstpredictedheight,rootmeansquareerror(RMSE),Akaike’sinformationcriterion(AIC),meanpredictionerror(ME)andmeanabsoluteerror(MAE).Theestimatedparameteraformodel(6)wasnotstatisticallysignificantatalevelofa=0.05.RMSEandAICtestresultforallmodelsshowedthatexponentialmodels(1),(2),(3)and(4)performedsignificantlybetterthanothers.AlltenmodelshadverysmallMEsandMAEs.Nearlyallmodelsunderestimatedtreeheightsexceptformodel(6).ComparingtheMEsandMAEsofmodels,model(1)producedsmallerMEs(0.0059)andMAEs(1.3754)thanothermodels.Toassessthepredictiveperformanceofmodels,wealsocalculatedMEsbydividingthemodelvalidationdatasetinto10-cmDBHclasses.ThissuggestedthatallmodelswerelikelytocreatehighermeanpredictionerrorsfortreeDBHclasses[20cm.However,nocleartrendwasfoundamongmodels.Model(6)generatedsignificantlysmallermeanpredictionerrorsacrossalltreeDBHclasses.Consideringalltheaforementionedcriteria,model(1):TH?1:3ta=e1tb?eàc?DBHTandmodel(6):TH?1:3tDBH2=eatb?DBHtc?DBH2Tarerecommendedassuitablemodelsfordescribingtheheight–diameterrelationsh
简介:Basedoninvestigationof53gapsand25quadrats(15m×15meach)ofnon-gapclosedstandinanold-growthtropicalmontanerainforestofHainanIsland,China,canopydisturbanceregimesandgapregenerationwerestudied.Gapswereellipticalinhorizontalform,theratiooflongaxis/shortaxiswasabout1.4.Percentageofexpandedgaps(EG)andcanopygaps(CG)areainthelandscapewere53.5%and25.2%respectively.EGrangedfrom31.4m2to488.2m2andCG/rom14.9m2to354.2m2,theiraveragesizes...
简介:Background:Thelargepotentialofthesoilorganiccarbon(SOC)pooltosequesterCO2fromtheatmospherecouldgreatlyamelioratetheeffectoffutureclimatechange.However,thequantityofcarbonstoredinterrestrialsoilslargelydependsuponthemagnitudeofSOCmineralization.SOCmineralizationconstitutesanimportantpartofthecarboncycle,andisdrivenbymanybiophysicalvariables,suchastemperatureandmoisture.Methods:Soilsamplesofapineforest,anoakforest,andapineandoakmixedforestwereincubatedfor387daysunderconditionswithsixtemperaturesettings(5°C,10°C,15°C,20°C,25°C,30°C)andthreelevelsofsoilmoisturecontent(SMC,30%,60%,90%).TheinstantaneousrateofmineralizedSOCwasperiodicallyandautomaticallymeasuredusingaLi-CorCO2analyzer.BasedonthemeasuredamountofmineralizedSOC,carbonfractionswereestimatedseparatelyviafirst-orderkineticone-andtwo-compartmentmodels.Results:Duringthe387dayincubationexperiment,accumulativemineralizedcarbonrangedfrom22.89mgcarbon(C)·g-1SOCat30°Cand30%SMCforthemixedforestto109.20mgC·g-1SOCat15°Cand90%SMCfortheoakforest.Mineralizedrecalcitrantcarbonvariedfrom18.48mgC·g-1SOCat30°Cand30%SMCforthemixedforestto104.98mgC·g-1SOCat15°Cand90%SMCfortheoakforest,andcontributedatleast80%tototalmineralizedcarbon.Conclusions:Basedontheresultsofthisexperiment,thesoilorganicmatterofthepurebroadleavedforestismorevulnerabletosoilmicrobialdegradationinnorthernChina;mostoftheamountofthemineralizedSOCderivedfromtherecalcitrantcarbonpool.Labilecarbonfractionconstitutesonaverage0.4%ofSOCacrossthethreeforesttypesandwasrapidlydigestedbysoilmicrobesintheearlyincubationstage.SOCmineralizationmarkedlyincreasedwithsoilmoisturecontent,andcorrelatedparabolicallytotemperaturewiththehighestvalueat15°C.Nosignificantinteractionwasdetectedamongthese