简介：Inthe20yearsaftertheUNEnvironmentandDevelopmentConferencein1992,theessentialissuesinrelationtosustainabledevelopmenthavebeenunsolved.Theupcoming"Rio+20"conferenceputthefocusontheshifttowardsgreendevelopment.Toachievethisrequiresthechangeofsomeideologiesthatdominatehumanactions,suchastheconceptsofwealth,welfareandsecurity,anditalsorequireidentifyingthenewpositionofnatureresources,especiallythepositionofforest.Itwaspointedoutinthepaperthatforestisthefoundationofsocioeconomicdevelopmentandconstitutesbasicwealth,basicwelfareandbasicsecurityofthewholecommunityunderthegreendevelopmentcontext.Nevertheless,itisamusttoaggressivelyinvestanddevelopgreeneconomy.Itwasalsoproposedtosetupforestrydevelopmentorganizations,investmentmechanisms,policysystemandresearch&educationsystemcompatiblewithgreendevelopment.Moreover,someforestrypoliciesthatshouldberevisedwerecombed.

简介：PoplarisoneofthedominanttreespeciesfortheestablishmentoffastgrowingplantationsinShandongProvince.EighteenpoplarclonesbelongingtoPopulusaigeirossectionwereintroducedfromItaly,Turkeyanddomesticregions.Populusdeltoidescv.'Lux'I-69/55(I-69),whichwaswidelyusedinShandongProvince,China,wastakenascontrolclone(I-69).Followingarandomizedcompleteblockdesign,seedlingtestandcontrolledafforestationtrialswerecarriedoutatJuxianCounty,CaoxianCountyandLaiyangCity.Theresultsshowedthatthepoplarclone(Populus×euramericanacv.'102/74'),namely102/74,performedwellbothintermsofadaptabilityandgrowthrate.Themeanheightof13.9m(H),diameteratbreastheightof18.0cm(DBH)andvolumegrowthof0.1445m3(V)were2.2%,21.6%and52.9%higherthanthoseofI-69(CK),respectively,attheageof5yearsatthreeexperimentalsites.Moreover,theclonecanbepropagatedeasilyandshowedhighresistancetopoplardisease,pestaswellassalinityandhadlongergrowingperiod.Furthermore,woodbasicdensityandfiberlengthofnewpoplarclone(102/74)wereassameasI-69(CK).Itwasconcludedthattheselectedclone(102/74)wasidealfortheestablishmentoffast-growingpoplarplantations,especiallyforthepulpwoodplantationsinShandongProvince.

简介：Modernforestryfocusingonecologicaldimensionneedssomenewindicatorsdifferentfromthosedesignedforthetraditionalforestry.Onthebasisoftheevaluationindicatorsfortraditionalforestry,suchasforestcoverage,totalstandingstockvolumeandforestvolumeperunitarea,thepapercameupwithanewindicatorcalled"forestthickness"(FT).FTreferstothethicknesswhichcanbegotifusingtotalstockvolumeofforestandtreestocoverthetotallandinagivenarea,anditischargedb...

简介：Twenty-fivenewclonesbelongtoPopulusAigeirosofbothdomesticandforeignoriginhadbeenintroducedandtestedatnurserystageinShandongprovince.Resultsshowedthatheight(H),diameteratstembase(DO)andsurvivalrate(SR)variedsignificantlyandgeneticvariationwereverylargeamongtheclones.CVgandbroad-senseheritability(h^2)ofH,DOandSRof1-year-oldstocknurserywere7.43%,9.25%,18.78%and78.91%,96.31%,95.93%,respectively,showinghighgeneticcontrolonthetestedtraits.11superiorcloneswithcharacteristicsofhighgrowthrateandmediumorhighSRwereprimarilyselectedandgeneticgains(△G)ofH,DOandSRwere16.89%,16.08%and13.08%,respectively.Rootinghabitstestofsomeselectedcloneswerealsoconductedbasedonthecuttingcultureinwatercontainerandannualgrowthincrementmeasured.Thedateoffirstrootemergence,numberofmainroots,numberoflateralroots,lengthofmainrootsandtheemergencedateofgrowthpeakvariedtocertaindegreeamongtheselectedclones.

简介：Thefeasibilityofthetechnologieshasbeendiscussedinthepaperthatbambooisusedformiddlingandtop-gradebuildingconstruction,architecturedecorating,andothermajorapplications.Thecontentincludesthecurrentapplicationofbamboomaterialsinconstructionfield;thebamboobearingmaterialtechnologicalprocesssuchasthelaminatedbambooboard,bamboomatplywoodprocesses;bambooceilingandwallmaterialtechnologiessuchasthebambooparticleboard,cement-bondedbambooparticlebo...

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简介：Urbanforestisanimportantcompositionandthewindowandsoulofmoderncities,whichhasacloserelationshipwithecologicalenvironmentandinvestingenvironment.SourbanforesthasbeenconstructedinChina.HuainingCountycouldholdofthehistoricalopportunityandcomeupwiththegreatblueprintofforestecologicalnetworksystemconstructionforthenewtown.Thispapermainlyintroducestheguidingideas,principles,goalsandoveralllayoutsoftheconstructioninthenewtown,andhopethatitwillbeamodelforothercounty-levelforestecologicalnetworksystemconstructioninChina.

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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

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简介：Background:Wildlifeandlivestockgrazingareimportantproductsofforestecosystems,butcanbecontroversial.HerbivorybyNorthAmericanelkanddomesticcattleisacontentiousmanagementissuethroughoutwesternNorthAmerica,oftendrivingmanagementproposalstodecreasecattleandelknumbersbasedonperceivedoverutilizationofforages.Suchobservationsareoftensitelevelratherthanlandscape,andmayconfuseecologicalsustainabilitywithdesiredconditions.Methods:Weusedlinetransectstodocumentvegetationcomposition,structure,andgrazingandbrowsingutilizationfor4keyhabitattypes:mountainmeadows,aspen,thinnedconifer,andburnedconiferonLincolnNationalForest,NewMexico,USA.Wedocumentedrelativehabitatuseofthesetypesbyelk,muledeer,andcattleandmodeledrelativeuseonresidualgrassbiomassofmountainmeadowsandbrowseutilizationofforestedtypes.Wedetermineddietsanddietqualityofelkandcattletoassessdegreeofcompetition.Results:Useofgrassesinmeadowswasbelowmanagementthresholds,andcombinedelk,cattle,anddeerrelativehabitatuseaccountedfor<14%ofthevarianceinresidualstubbleheightofPoapratensis,themostabundantgrass.Palatablebrowsewaslimitedinhabitattypes(<107stems·ha~(-1)),usewasgenerallyhigh,andelkpresencewascorrelatedwiththemajorityofbrowsing.Elkandcattledietsdidnotsignificantlyoverlap(Schoener'sindex0.54–0.57);elkfedprimarilyondeciduousshrubs(34%–55%ofannualdiets)andcattleongrass(72%–77%).Digestibilityandcrudeproteinlevelsofcattledietsandbodyconditionofelkindicatedhighqualitydietsforcattleandmarginal–goodqualitydietsforelk.Conclusions:Atobservedstockinglevelsanddensities,cattleandelkwerenotcompetingforforagebasedondietsimilarity,norwerekeyhabitattypesbeingusedbeyondsustainablelevels.LowbrowseavailabilityindicatesthatopportunityexiststoincreaseforageavailabilityonLincolnNationalForest,andthusmaintainorincreasepopu

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简介：Background:Theimportanceofstructurallydiverseforestsfortheconservationofbiodiversityandprovisionofawiderangeofecosystemserviceshasbeenwidelyrecognised.However,toolstoquantifystructuraldiversityofforestsinanobjectiveandquantitativewayacrossmanyforesttypesandsitesarestillneeded,forexampletosupportbiodiversitymonitoring.Theexistingapproachestoquantifyforeststructuraldiversityarebasedonsmallgeographicalregionsorsingleforesttypes,typicallyusingonlysmalldatasets.Results:HerewedevelopedanindexofstructuraldiversitybasedonNationalForestInventory(NFI)dataofBadenWurttemberg,Germany,astatewith1.3millionhaofdiverseforesttypesindifferentownerships.Basedonaliteraturereview,11aspectsofstructuraldiversitywereidentifiedaprioriascruciallyimportanttodescribestructuraldiversity.Aninitialcomprehensivelistof52variablesderivedfromNationalForestInventory(NFI)datarelatedtostructuraldiversitywasreducedbyapplyingfiveselectioncriteriatoarriveatonevariableforeachaspectofstructuraldiversity.Thesevariablescomprise1)quadraticmeandiameteratbreastheight(DBH),2)standarddeviationofDBH,3)standarddeviationofstandheight,4)numberofdecayclasses,5)bark-diversityindex,6)treeswithDBH>40cm,7)diversityoffloweringandfructification,8)averagemeandiameterofdowneddeadwood,9)meanDBHofstandingdeadwood,10)treespeciesrichnessand11)treespeciesrichnessintheregenerationlayer.Thesevariableswerecombinedintoasimple,additiveindextoquantifythelevelofstructuraldiversity,whichassumesvaluesbetween0and1.Weappliedthisindexinanexemplarywaytobroadforestcategoriesandownershipstoassessitsfeasibilitytoanalysestructuraldiversityinlarge-scaleforestinventories.Conclusions:Theforeststructureindexpresentedherecanbederivedinasimilarwayfromstandardinventoryvariablesformostotherlarge-scaleforestin

简介：Background:Growthandyieldmodelsareimportanttoolsforforestplanning.Duetoitsgeographiclocation,topology,andhistoryofmanagement,theforestsoftheAdirondacksRegionofNewYorkareuniqueandcomplex.However,onlyarelativelylimitednumberofgrowthandyieldmodelshavebeendevelopedand/orcanbereasonablyextendedtothisregioncurrently.Methods:Inthisanalysis,571long-termcontinuousforestinventoryplotswithatotalof10-52yearsofmeasurementdatafromfourexperimentalforestsmaintainedbytheStateUniversityofNewYorkCollegeofEnvironmentalScienceandForestryandonenonindustrialprivateforestwereusedtodevelopanindividualtreegrowthmodelfortheprimaryhardwoodandsoftwoodspeciesintheregion.Species-specificannualizedstaticanddynamicequationsweredevelopedusingtheavailabledataandthesystemwasevaluatedforlong-termbehavior.Results:EquivalencetestsindicatedthattheNortheastVariantoftheForestVegetationSimulator(FVS-NE)wasbiasedinitsestimationoftreetotalandboleheight,diameterandheightincrement,andmortalityformostspeciesexamined.Incontrastthedevelopedstaticandannualizeddynamic,species-specificequationsperformedquitewellgiventheunderlyingvariabilityinthedata.Long-termmodelprojectionswereconsistentwiththedataandsuggestarelativelyrobustsystemforprediction.Conclusions:Overall,thedevelopedgrowthmodelshowedreasonablebehaviorandisasignificantimprovementoverexistingmodelsfortheregion.Themodelalsohighlightedthecomplexitiesofforestdynamicsintheregionandshouldhelpimproveforestplanningeffortsthere.

简介：属于12个类的36种和1亚种，从中国的Mao'ershan区域(Heilongjiang省)收集的家庭Eumolpidae的3个亚科在这篇论文被列出包括一新记录种，Cryptocephalus阎罗王奶妈Chujo，1940，从中国。对新记录种类的描述和相片也被提供。

简介：１三棘华枝ＳｉｎｏｐｈａｓｍａｔｒｉｓｐｉｎｏｓｕｍＣｈｅｎｅｔＣｈｅｎ，ｓｐ．ｎｏｖ．本新种与臀沟华枝ＳｉｎｏｐｈａｓｍａｌａｔｉｓｅｃｔｕｍＣｈｅｎｅｔＣｈｅｎ近似，但本种雄性臀节端部较窄，纵沟浅裂．背面具有３个排列成倒三角形的锥形突，第９节背板隆起成直角下垂等不同，可相区别．模式标本保存在中山大学．２单棘华枝ＳｉｎｏｐｈａｓｍａｕｎｉｓｐｉｎｏｓｕｍＣｈｅｎｅｔＣｈｅｎ，ｓｐ．ｎｏｖ．本新种与三棘华枝ＳｉｎｏｐｈａｓｍａｔｒｉｓｐｉｎｏｓｕｍＣｈｅｎｅｔＣｈｅｎ近似，但本种雄性臀节较狭长，两侧端叶扩展成瓣状；端部无纵沟，背面具有１个明显的锥形突，下生殖板形状以及第９节背板明显不同等，可相区别．模式标本保存在中山大学．３拟异尾华枝（雌性）ＳｉｎｏｐｈａｓｍａｐｓｅｕｄｏｍｉｒａｂｉｌｅＣｈｅｎｅｔＣｈｅｎ本种发表于１９９６年，当时仅报道其雄性，近在中山大学昆虫标本馆发现１对雌雄，其雌性与异尾华枝ＳｉｏｎｐｈａｓｍａｍｉｒａｂｉｌｅＧüｎｔｈｅｒ雌性相似．但本种头部形状，第７腹节腹板与腹瓣伸至的位置，以及尾须的形状等明显不同，可与之区别．模式标本保存在北京林业大学和中山大学．

简介：Threeessentialfactorsofforestfire(firesource,environment,andlitter)weretakenasthepointofview,andhasapproachedtheforecastmethodofforestfireintropicalareaofsouthwestChinainamacroscopicscale.Thisstudysupportedbymathematicalmethodwasfromanewangle.Forexample,intheaspectofforestfireforecast,ithasbeenthoughtoverthatmostforestfireisartificialfire,whichhaslotsofrandomness.SoitcouldbestudiedinakindofMarkovrandomprocesses.Inthe...