简介：木质的种类的差异和新生在二生态的壁龛viz被调查。在旧生长的季节联盟者的差距和未经触动的植被弄干Shorea柔韧一(Gaertn。f.)在尼泊尔的森林。我们也联系了差异措施和新生属性的变化到差距特征。树和灌木部件的茎密度比在未经触动的植被在差距是更高的。S的幼苗密度。柔韧andTerminaliaalata(B。Heyne前Roth)比在未经触动的植被在差距是更高的，当矛盾的结果为T被观察时。bellirica(Gaertn。前Roxb)并且Syzigium枯茗i(L。Skeels)以幼苗密度。在幼苗层的Simpson索引，平均索引，和种类个人比率的补充比未经触动的植被在差距是更低的。差距尺寸能解释种类丰富和种类建立率。在不同的年里到多重树下降创造的差距有S的更高的幼苗密度。柔韧a比单个或多重的树创造的差距掉在一样的年里。在结论，差距由增加柳安森林的幼苗密度，和帮助新生维持种类差异。除了差距尺寸，另外的差距属性也影响种类差异和新生。

简介：这研究的目的是在不平的里海的森林里为单个树估计一个基础区域生长模型。调查被进行以便发现没有任何收获活动，一个那么叫的未触动过的森林和一个区域的一个自然森林从伊朗的里海的森林被选择。在一样的方面并且一样的森林类型的三个样品阴谋被选择。在每个阴谋，总计树高度，在胸高度的直径，邻居树和方位角的距离被测量。三十棵树被选择并且与增长borer钻了决定增长模型。回归分析被用来估计生长模型。结果证明为单个树，在年度基础区域增长之间有一种重要非线性的关系，作为依赖变量，和基础区域。结果也证明竞争的树的基础区域在生长上有积极影响。增长与更多是更高的竞争附近的树可能因为阴谋与每公顷和更多的竞争大量，也很可能每公顷与更低的体积比阴谋有更高的地点索引或良土或更好的地点生产率。

简介：Blacklocust(RobiniapseudoacaciaL.)wasthefirstNorth-AmericantreespeciesimportedtoEuropeatthebeginningoftheseventeenthcentury.Itiscommonlyplantedworldwidebecauseofitsadaptabilitytoenvironmentalstresses,itsvaluablewood,easypropagation,frequentandabundantseedproduction,excellentcoppicing,highseedlingsurvival,andrelativelyhighwoodyield.InEurope,RomaniaandHungaryhavethemosthighly-developedblacklocustgrowingtechniquesandexperiences.Asaresultofincreasinginterestinblacklocustinmanycountries,thisreviewaimstoprovideacomprehensiveoverviewofstate-of-the-artsiterequirements,propagation,improvementandmanagement(includinggrowthandyieldaswellasuseinenergyplantations).

简介：我们使用了GIS和最大的熵预言六蛇种的潜在的分发在Kroumiria(西北的突尼斯)属于三个家庭：Natricidae(Natrixmaura和Natrixastreptophora)，Colubridae(Hemorrhoishippocrepis，Coronellagirondica和Macroprotodonmauritanicus)，和Lamprophiidae(Malpoloninsignitus)。为每种的合适的产地用最大的熵算法被建模，联合存在地数据(在16期间镇定?年：2000-2015)与一套七个环境变量(吝啬的年度降水，举起，斜坡坡度，方面，到水路的距离，陆地表面温度和规范的微分植被索引。这些环境变量的相对重要性被大折刀测试评估，我们的模型的预兆的力量在操作特征的接收装置下面用区域被估计。种类分发的主要解释变量是来自流和举起的距离，与分别地从60～77并且从10～25%的贡献。我们的学习提供了适用性在Kroumiria为蛇建模的第一个产地，这个信息能被担心在Kroumiria保存蛇的保存生物学家和陆地经理使用。

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。

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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：估计并且使用的树种类(异国情调或本国)与到环境压力的优异忍耐(例如干旱和高温度)在造林惯例起一个重要作用。在到三树种的周围的气象学的因素的现在的学习，茎树液流动特征和回答，Albizziakalkora(土著人)，Azadirachtaindica(异国情调)，并且相思树auriculaeformis(异国情调)，在一条干燥热的山谷(Yuanmou，云南省，中国)用热驱散探针被调查。日报在三学习的种的树液流动的动力学显示了明显的生理节奏的节奏在期间湿并且旱季，与A的例外。indica在旱季期间。在A的树液流动速度(SFV)。kalkora和A。auriculaeformis断然显著地与光合地活跃的放射(同等)被相关，空气温度，蒸汽压力赤字(VPD)和风加速，但是否定地在二个季节与大气的相对湿度相关。跨关联的分析也表明三种的SFV显著地与同等和VPD被相关(P?一。indica有更高的干旱抵抗并且对学习区域的造林更好。

简介：Background:Seedproduction,seeddispersalandseedlingestablishmentarerelevantlifephasesofplants.Understandingtheseprocessesandtheirpatternsisessentialtorecognizevegetationdynamicsandtoapplyittoforestrestoration.Methods:ForOleaeuropaeaandScheffleraabyssinica,fecunditywasestimatedusingrandomizedbranchsampling.Seeddispersalandseedlingestablishmentweremonitoredusingspatiallyexplicitseedtrapsandplots.Dispersalfunctionswerecalibratedapplyinginversemodeling.Results:O.europaeaproducedmoreseedsandhadlongerdispersaldistancescomparedtoS.abyssinica.Correlationsbetweenobservedandpredictednumberofrecruitswerestatisticallysignificant.Seedlingsofthetwospeciesshoweddifferentnicherequirements.Conclusions:Thestudiedspecieswererecruitment-limitedduetolowdispersalactivityorlackofsuitablemicrosites.Restorationrelyingonnaturalregenerationshouldovercometheselimitationsbyincreasingdisperservisitationandreducingbioticandabioticstresses.

简介：QuantitativeassessmentoftreespeciesdiversityfromsampleplotsinsevenforestrangesofNayagarhForestDivisioninOdishastateintheEasternGhatsofIndiawasmadeduringtheperiodApril,2011toNovember,2013.Atotalof120transects(1000m95m)werelaidinNayagarh,Odogaon,Pancharida,Khandapada,Dasapalla,Mahipur,andGaniaforestrangesandtreestemsofatleast30cmGBHweremeasured.Theregenerationpotentialoftreeswasassessedfrom5m95msampleplotslocatedwithinthemaintransect.Atotalof177treespeciesbelongingto120generaand44familieswererecordedfromthestudyarea.Shorearobusta,Buchananialanzan,Lanneacoromandelica,TerminaliaalataandCleistanthuscollinuswerethepredominanttreespecies.Thestanddensityvariedintherangeof355.33-740.53stemsha-1whilebasalarearangedfrom7.77to31.62m2ha-1.Thetreedensityandspeciesrichnessdecreasedwithincreasinggirthclass.Thehighestnumberofspeciesandmaximumdensitywasrecordedinthegirthclassof30-60cm.TheShannon-WeinerandSimpsonIndiceswithrespecttotreeswithC30cmGBHvariedintherangeof2.07-3.79cmand0.03-0.37cmrespectivelyandthevaluesofdiversityindicesarewithinthereportedrangefortropicalforestsofIndiansub-continent.Thefamilies,Dipterocarpaceae,Anacardiaceae,CombretaceaeandEuphorbiaceaecontributedtomaximumspeciesrichness,standdensity,andbasalarea.Regenerationofmanytreespecieswasobservedtobepoor.Thepresentstudyprovidesbaselinedataforfurtherecologicalstudies,forestmanagement,andformulationofsite-specificstrategiesforconservationofbiologicaldiversityinmoistdeciduousforestsofEasternIndia.

简介：Background:Coarsewoodydebris(CWD)isveryimportantforforestecosystems,particularlyforbiodiversityandcarbonstorage.Itsrelevanceasapossiblereservoirandsourceofnutrientsislessclear,especiallyincentralEurope.Methods:Basedonachronosequenceofknownagesoflogs,weanalyzedthenutrientsstoredinCWDofFagussylvatica,Piceaabies,andPinussylvestrisatdifferentsitesinGermany.Toquantifynutrientconcentrations,weassessedtheuseofNearInfraredReflectanceSpectroscopy(NIRS)todeterminethechemicalpropertiesofCWD.Results:NIRSmodelsweresuitabletopredictconcentrationsofC,N,P,ligninandextractives.Concentrationsofmostnutrientsincreasedwithmassloss,withtheexceptionofpotassium,whichdecreasedforbeechandpineandremainedrelativelyconstantforspruce.Thehighestnutrientconcentrations(N,P,S,CaandMn,exceptMgandK)weregenerallyobservedinhighlydecomposedsprucelogs.TheneteffectofdecreasingCWDmassandincreasingnutrientconcentrationswaseitheradecreasing(N,PandKinbeech;P,Mg,KandMninpine),constant(S,CaandMginbeech;N,SandCainpine)orincreasingamountofnutrients(N,P,SandCainspruce;Mninbeech)inthelogsoverthecourseofdecomposition.TheC/Nratiodecreasedforalltreespecies,mostmarkedlyforsprucefromca.1000atthebeginningofthedecompositionprocessto180at36years.TheN/Pratioconvergedtoavalueofabout30forallthreespecies.Ligninconcentrationsincreasedforspruceandbeechandremainedconstantforpine.Conclusions:OurresultsindicatethatmostnutrientsremaininCWDforlongperiods.NutrientsmaybeusedandcycledbymicroorganismswithinCWD,butwiththeexceptionofP(inbeech),Mg(inpine)andK(inbeechandpine),thereappearstobelittlenetnutrientexportuntiltwothirdsofthemassislost.Instead,N,P,SandCawereaccumulatedinsprucelogs,indicatingthatCWDbecameanetsinkratherthananetsourceofsomenutrientsforsevera

简介：Background:Prosopisspecieshavebeenintroducedtomanyareasoutsidetheirnativerangetoprovidebenefitstolocalcommunities.SeveralProsopisspeciesandtheirhybrids(hereafter"mesquite")have,however,becomenaturalisedandinvasiveandnowgeneratesubstantialcosts.Managementoptionsarelimitedbecauseofthecomplexconflictsofinterestregardingbenefitsandcosts.Managementpoliciesandstrategiesmusttakeaccountofsuchconflicts,butfurtherinsightsareneededonthedimensionsofusesandimpactsbeforesuchinformationcanbeusefullyapplied.CurrentpolicyinSouthAfricaallowsforthegrowthanduseofmesquiteinoneprovince,butnotinotherswhereitscontrolismandatory.Wereportonastudytoquantifythedirectuseandperceptionsofnon-timberforestproducts(NTFPs)frommesquiteandnativetreesinSouthAfrica.Methods:Semi-structureshouseholdinterviewswereconductedwithvariousstakeholdergroupstoidentifywhattreeproductsareused,toascertainamountsusedaswellastogaugeperceptionsofnaturalresourceusebetweendifferenttreespeciesanduseovertime.Results:Thedirecthouseholdusevalueofnativetreeswashigherthanthatofmesquite,andlocalstakeholdersattachedgreatervaluetoproductsfromnativetreesthanfrommesquite.Therefore,nativetreesareandwillstillbepreferentiallyharvested,andmesquiteisunlikelytoofferprotectiontonativespeciesbyprovidinganalternativesourceofproducts.Mesquitepodsdo,however,providevaluableadditionalresources(fodderandmedicinalproducts).Theuseofbothnativetreesandmesquiteisdecreasingastheincomesofpoorerhouseholdsriseandasalternativeenergysourcesbecomeavailable.Thebenefitsandrelianceonmesquitearenotashighaspreviouslyassumedandtheimpactsfrommesquiteinvasionscreatelargeproblemsforlocalcommunities.Conclusion:Thisstudyprovidesfurtherevidencethattheimpactsofmesquiteexceedthebenefits,lendingsupportforapolicytoreducenegat

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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.

简介：Background:Treespeciesrecognitionisthemainbottleneckinremotesensingbasedinventoriesaimingtoproduceaninputforspecies-specificgrowthandyieldmodels.Wehypothesizedthatastratificationofthetargetdataaccordingtothedominantspeciescouldimprovethesubsequentpredictionsofspecies-specificattributesinparticularinstudyareasstronglydominatedbycertainspecies.Methods:Wetestedthishypothesisandanoperationalpotentialtoimprovethepredictionsoftimbervolumes,stratifiedtoScotspine,Norwayspruceanddeciduoustrees,inaconiferforestdominatedbythepinespecies.Wederivedpredictorfeaturesfromairbornelaserscanning(ALS)dataandusedMostSimilarNeighbor(MSN)andSeeminglyUnrelatedRegression(SUR)asexamplesofnon-parametricandparametricpredictionmethods,respectively.Results:TherelationshipsbetweentheALSfeaturesandthevolumesoftheaforementionedspecieswereconsiderablydifferentdependingonthedominantspecies.Incorporatingtheobserveddominantspeciesinthepredictionsimprovedtherootmeansquarederrorsby13.3-16.4%and12.6-28.9%basedonMSNandSUR,respectively,dependingonthespecies.Predictingthedominantspeciesbasedonalineardiscriminantanalysishadanoverallaccuracyofonly76%atbest,whichdegradedtheaccuraciesofthepredictedvolumes.Consequently,thepredictionsthatdidnotconsiderthedominantspeciesweremoreaccuratethanthoserefinedwiththepredictedspecies.TheMSNmethodgaveslightlybetterresultsthanmodelsfittedwithSUR.Conclusions:Accordingtoourresults,incorporatinginformationonthedominantspecieshasaclearpotentialtoimprovethesubsequentpredictionsofspecies-specificforestattributes.DeterminingthedominantspeciesbasedsolelyonALSdataisdeemedchallenging,butimportantinparticularinareaswherethespeciescompositionisotherwiseseeminglyhomogeneousexceptbeingdominatedbycertainspecies.

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