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  • 简介:Forestshavemultiplebenefitsandfunctions,includingmitigationofclimatechange.Theimpactsofforestsontheglobalcarboncycleincludeforestsascarbonsinks,wood-basedproductsascarbonsinks,bio-energy,andproductionanduseofnon-timberproducts.Inthepastdecades,forestcoverofChinahasincreasedfrom8.6%to18.21%bylarge-scaleafforestationandconversionofcroplandintoforests.Forestbiomasscarbon(C)stockincreasedfrom4.3PgC(1PgC=1015gC)intheearly1980sto5...

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  • 简介:Inrecentdecades,therehasseenadramaticexpansionofglobalplantedforestareaandtheirgreatimpactonhumanlife.ItisreportedinForestResourceAssessment2010thatthecurrentareaofglobalplantedforestsisabout264millionha,representingonly7%ofthetotalforestareabutabletomeetthetwothirdsoftheglobaldemandforlogs.Plantedforestscannotonlyprovidetimber,fiber,fuelandnon-woodforestproducts,butalsocontributetocarbonsequestration,restorationofdegradedl...

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  • 简介:Theoryandevidenceindicatethattreesandothervegetationinfluencetheatmosphericwater-cycleinvariousways.Theseinfluencesaremoreimportant,morecomplex,andmorepoorlycharacterisedthaniswidelyrealised.Whilethereislittledoubtthatchangesintreecoverwillimpactthewater-cycle,thewiderconsequencesremaindifficulttopredictastheunderlyingrelationshipsandprocessesremainpoorlycharacterised.Nonetheless,asforestsarevulnerabletohumanactivities,theselinkedaspectsofthewater-cyclearealsoatriskandthepotentialconsequencesoflargescaleforestlossaresevere.Here,fornon-specialistreaders,Ireviewourknowledgeofthelinksbetweenvegetation-coverandclimatewithafocusonforestsandrain(precipitation).Ihighlightadvances,uncertaintiesandresearchopportunities.Therearesignificantshortcomingsinourunderstandingoftheatmospherichydrologicalcycleandofitsrepresentationinclimatemodels.Abetterunderstandingoftheroleofvegetationandtree-coverwilreducesomeoftheseshortcomings.Ioutlineandilustratevariousresearchthemeswheretheseadvancesmaybefound.Thesethemesincludethebiologyofevaporation,aerosolsandatmosphericmotion,aswellastheprocessesthatdeterminemonsoonsanddiurnalprecipitationcycles.Anoveltheory-the‘bioticpump’-suggeststhatevaporationandcondensationcanexertamajorinfluenceoveratmosphericdynamics.Thistheoryexplainshowhighrainfallcanbemaintainedwithinthosecontinentalland-massesthataresufficientlyforested.Feedbackswithinmanyoftheseprocessescanresultinnon-linearbehavioursandthepotentialfordramaticchangesasaresultofforestloss(orgain):forexample,switchingfromawettoadrylocalclimate(orvisa-versa).Muchremainsunknownandmultipleresearchdisciplinesareneededtoaddressthis:forestscientistsandotherbiologistshaveamajorroletoplay.Newideas,methodsanddataofferopportunitiestoimproveunderstanding.Expectsurpr

  • 标签: Biotic pump Climate Condensation EVAPORATION Ice-nucleation
  • 简介:Climatechangeisagreatconcernofvariouscountries,thepublicandsciencecommunity,andforestplaysanimportantroleinmitigatingclimatechange.ThepapermadeacomprehensiveanalysisregardingthepolicyselectionsofChinatopromoteforestryresponsetotheglobalclimatechange,andelaboratedtheconcreteactionsandachievementsinthisregard.Policyselectionsinclude:1)Reinforcetreeplantingandafforestation,increasetheforestedareaandenhancethecapacityofcarbonsequestration...

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  • 简介:火的相互作用骑车,植物硬币的繁殖特征能决定一处风景的植被分发模式。在加拿大的北方的区域,火在小冰川期前骑车(c。1850年代)以后从30-130年和25-234年直到解决时期(c。1930年代)什么时候更长发射周期,响应气候变迁和人的干扰发生了。分析显示火周期与生长期(4月10月)被相关从1961-1990正常的温度和降水离开,由区域变化。假设野火将在过去的世纪,用气候变迁情形CGCM1的一个评价,CGCM2和HadCM2期间对类似于方式的温暖的未来作出回应显示周期将在西方泰加森林盾转移到80-140年的一个范围的火,为北方的盾和东方泰加森林防护的东方的超过700年,和为在2050的北方的平原的300-400年。

  • 标签: 加拿大 北部地区 北方针叶林 森林 火灾周期 全球气候变化
  • 简介:Thecircumborealforestencompassesdiverselandscapestructures,dynamicsandforestagedistributionsdeterminedbytheirphysicalsetting,andhistoricalandcurrentdisturbanceregimes.However,duetointensifyingforestutilisation,andincertainareasduetoincreasingnaturaldisturbances,borealforestage-classstructureshavechangedrapidly,sothattheproportionofoldforesthassubstantiallydeclined,whilethatofyoungpost-harvestandpost-natural-disturbanceforestproportionshaveincreased.Inthefuture,withawarmingclimateincertainborealregions,thistrendmayfurtherbeenhancedduetoanincreaseinnaturaldisturbancesandlarge-scaleuseofforestbiomasstoreplacefossil-basedfuelsandproducts.Themajordriversofchangeofforestageclassdistributionsandstructuresincludetheuseofclearcutshortrotationharvesting,morefrequentandseverenaturaldisturbancesduetoclimatewarmingincertainregions.Thedeclineinoldforestarea,andincreaseinmanagedyoungforestlackingnaturalpost-disturbancestructurallegacies,representamajortransformationintheecologicalconditionsoftheborealforestbeyondhistoricallimitsofvariability.Thismayintroduceathreattobiodiversity,ecosystemresilienceandlong-termadaptivecapacityoftheforestecosystem.Tosafeguardborealforestbiodiversityandecosystemfunctioning,andtomaintainthemultipleservicesprovidedtosocietiesbythisforestbiome,itispivotaltomaintainanadequateshareandtheecologicalqualitiesofyoungpost?disturbancestages,alongwithmatureforeststageswithold-growthcharacteristics.Thisrequiresmanagementfornaturalpost-disturbancelegacystructures,andinnovativeuseofdiverseuneven-agedandcontinuouscovermanagementapproachestomaintaincriticallate-successionalforeststructuresinlandscapes.

  • 标签: Adaptive capacity BIODIVERSITY BOREAL FOREST Climate
  • 简介:Background:Thispaperexploredthelong-term,ceteris-paribuseffectsofpotentialCO,fertilizationontheglobalforestsector.BasedonthefindingsofNorbyetal.(PNAS2005,102(50))aboutforestresponsetoelevated[CO_2].Methods:ForestproductivitywasincreasedintheGlobalForestProductsModel(GFPM)inproportiontotherising[CO.,]projectedintheIPCCscenarioA1B,A2,andB2.Projectionsoftheforestareaandforeststockandoftheproduction,consumption,prices,andtradeofproductsrangingfromfuelwoodtopaperandpaperboardwereobtainedwiththeGFPMforeachscenario,withandwithoutCO_2fertilizationbeginningin2011andupto2065.Results:C02fertilizationincreasedwoodsupply,leadingtolowerwoodpriceswhichinturninducedmodestlowerpricesofendproductsandhigherglobalconsumption.However,productionandvalueaddedinindustriesdecreasedinsomeregionsduetotherelativecompetitiveadvantagesandtothevaryingregionaleffectsofCO_2fertilization.Conclusion:ThemaineffectofCO,fertilizationwastoraisetheleveloftheworldforeststockin2065by9to10%forscenariosA2andB2andby20%forscenarioA1B.Theriseinforeststockinducedbyfertilizationwasinpartcounteractedbyitsstimulationofthewoodsupplywhichresultedinlowerwoodpricesandincreasedharvests.

  • 标签: 二氧化碳施肥 森林工业 CO2施肥 木材价格 森林生产力 产品模型
  • 简介:Globalclimatechangeposesnewopportunitiesandchallengesforforestrydevelopment,andthereforedevelopingmultiple-purposeforestryisanimportantmeasuretostrengthenforestryresponsetoclimatechange.Atpresent,plantationinChinarankstheworldfirstinarea,butwithrelativelylowproductivity.Constantlyexpandingforestareaandimprovingforestmanagementforenhancingmultiplefunctionsandpurposesofplantationsarethekeymeasurestoupgradeplantationcapacitytomitigateandadap...

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