简介：综合Adaboost算法的自适应再加权和随机森林算法的未修剪随机变量划分树基模型，文章提出了用于自适应随机森林算法。通过实验数据发现，在训练集较大、贝叶斯误差较小时，模拟自适应再加权会起作用，从而，拟自适应随机森林算法会优于随机森林算法。

简介：精确的网络流量分类是实现互联网可控可管的关键，传统的单一分类算法需要构建基于特定假设的某种模型，算法对于待分类数据的分布要求高，不能满足复杂多变的网络流量的分类要求。基于此，采用多决策树组合的随机森林算法实现网络流量分类。通过实际网络流量数据实验表明，在各种情况下，随机森林算法都能显著改善网络流量特别是小比例样本的分类效果，算法降低了单一算法过于依赖特定假设模型的要求，对于待分类样本的分布要求低，随机森林算法具有良好的分类效果和鲁棒性。

简介：《国务院关于在市场监管领域全面推行部门联合“双随机、一公开”监管的意见》强调要坚持问题导向,提出“实施信用风险分类监管,针对突出问题和风险开展双随机抽查,提高监管精准性”。《市场监管总局关于全面推进“双随机、一公开”监管工作的通知》在规范随机抽取检查对象时也提出“针对不同风险程度、信用水平的检查对象采取差异化监管措施,合理确定、动态调整抽查比例和检查对象被抽查概率”。

简介：摘要：随着科学技术的发展，我国的森林遥感图像分类技术有了很大进展，在我国现阶段的众多高校中，都开设了“遥感图像解译”或“遥感原理与应用”等课程。遥感图像的监督分类，是遥感类课程不可或缺的教学内容。然而，在目前相关课程的实验教学中，存在教学内容陈旧、更新频率较低等问题。为了充实高校遥感类课程的实验教学，本文首先分析了随机森林回归模型，其次探讨了遥感图像分类实验教学软件设计，以供参考。

简介：ＦｏｒｅｓｔｉｎＴｉｂｅｔ￥ＸＵＸＩＡＯＱＩＮＧａｎｄＧＵＡＮＨＯＮＧＳＨＵＰｒｉｍｉｔｉｖｅｆｏｒｅｓｔｓ，ｃｏｖｅｒｉｎｇ７．１５ｍｉｌｌｉｏｎｈｅｃｔａｒｅｓ，ｍａｋｅｕｐ９９．７ｐｅｒｃｅｎｔｏｆｔｏｔａｌｆｏｒｅｓｔｓｉｎＴｉｂｅｔ．Ｔｈｅ...

简介：角色:A—AllanimalsB—BirdC—CatD—DeerF—FoxG—TigerM—MonkeyR—RabbitS—StorytellerT—Tortoise场景:树、花草、蘑菇等S:Hello,friends.Youknowtherearemanyanimalsintheforest.Theyaresinginganddancing.Theyareveryhappy.Look,theyarecoming.

简介：aSpringerOpenJournalwww.forestecosyst.comAimsandScopeForestEcosystemsisaninternationalOpenAccessjournalpublishingscientificcommunicationsfromanydisciplinethatcanprovideinterestingcontributionsaboutthestructureanddynamicsof'natural'and'domesticated'forestecosystems,andtheirservicestopeople.Wewelcomeinnovativescienceaswellasapplicationorientedworkthatwillenhanceunderstandingofwoody

简介：BasedontheinvestigationinAnjiCountyofZhejiangProvinceandBa'nanDistrictofChongqing,thispaperanalyzedthecharacteristicsofforestmanagementbehaviorsofforestfarmersinChinaandtheimpactfactorsforforestmanagementincome,andthencameupwithsomepolicyrecommendationstoincreasetheforestmanagementincomeofforestfarmers.ItarguedthatthefactorstoimpactonforestmanagementincomeofforestfarmersinChinaincludethechoiceofforestproductstype,theelementsinfo...

简介：Thepaperwasbasedonthecurrentdevelopmentstatusofforestcertificationtoanalyzethebasiccharacteristicsofforestcertificationfromthedevelopmentpointofviewintermsoforigin,development,maindriversandimpacts,andthenconductedtheapproachanalysistopromotesustainableforestmanagementwithforestcertificationinChina.TheresultshowedthatChinashallestablishherownforestcertificationscheme,withthefocusontheimprovementofforestsustainablemanagementconceptthro...

简介：Thoughpublicforestsincountriestakeupasmallportionofforests,theirimportanceinrespectofenvironmentalsideloomslargegradually.ThispaperstudiesandcomparesthepublicforestmanagementandforestlawsinFranceandtheUSA,attemptingtoexploretheforestoperationpracticeinbothcountriesandtheemphasisofthelawgoverningforestmanagement,sothatalessoncanbedrawnforustolearninChina.

简介：自从1990年代，在朝鲜，损坏与气候变化有关的台风稳定地增加了。红松(Pinusdensiflora)在光纽恩格·福雷斯特的森林被台风Kompasu极大地在2010扰乱。调查被执行在地面甲壳虫澄清差别(翘目：Carabidae)在森林差距和undamaged森林之间的社区。地面甲壳虫从早5月用陷井陷井被取样到2011年10月下旬。植被变化，崽层，有机物层，和土壤条件也被测量。32种类的1035地面甲壳虫的一个总数是镇定的。与我们的期望相反，地面的种类丰富，丰富，和社区结构在森林差距急速移动类似于undamaged森林里的那些。种类丰富和许多产地类型也是类似的。然而，在森林差距的种类差异和估计的种类丰富比在undamaged森林里显著地高。这些调查结果建议台风形成的森林差距没导致伟人改变观点甲壳虫社区。

简介：Background:Theglobaldecreaseinwildlifepopulations,especiallybirds,ismainlyduetolandusechangeandincreasingintensityoflanduse(ParmesanandYohe2003).However,impactsofmanagementtoolstomitigatebiodiversitylossatregionalandglobalscalesarelessapparentinforestregionsthathaveaconstantforestarea,andwhichdidnotsufferfromhabitatdegradation,andwhereforestsaresustainablymanaged,suchasinCentralEuropeorthenortheasternUSA.AbiodiversityassessmentforGermanysuggested,forexample,thatbirdpopulationswereconstant(BundesamtfürNaturschutz2015).Results:Thisstudyshowsthatchangesintheenvironmentandinforestmanagementoverthepast45yearshavehadasignificant,positiveeffectontheabundanceofnon-migratoryforestbirdspeciesinCentralEurope.Economy(timberpricesandGDP),forestmanagement(timberharvestandmixedforestarea),andenvironmentalfactors(atmosphericCO2concentrationandnitrogendeposition)wereinvestigatedtogetherwithchangesinabundancesofmigratoryandnon-migratoryforestbirdsusingpartialleastsquarespathmodeling.Climatechange,resultinginlongerseasonsandmilderwinters,andforestmanagement,promotingtreediversity,weresignificantlypositivelyrelatedtotheabundanceofnon-migratoryforestbirdsandexplained92%ofthevariationintheirabundanceinEurope.Regionally-migratingforestbirdshadstablepopulationswithlargevariation,whilebirdsmigratingacrosscontinentsdeclinedinrecentdecades,suggestingsignificant,contrastingchangesinbirdpopulationsinEurope.InnortheasternNorthAmericawealsofoundevidencethatnon-migratoryforestshaveexperiencedlong-termincreasesinabundance,andthisincreasewasrelatedtomanagement.TheincreaseofpopulationsofnonmigratoryforestbirdsinEuropeandNorthAmericaisassociatedwithanincreaseinstructuraldiversityanddisturbancesatthelandscapelevel.Conclusions:Ourresultssuggestthatreportsaboutbirddecline

简介：Background:Climatechangeislikelytocausesignificantmodificationsinforests.Risingtothischallengemayrequireadaptationofforestmanagement,andthereforeshouldtriggerproactivemeasuresbyforestmanagers,butitisuncleartowhatextentthisisalreadyhappening.Methods:ThesurveycarriedoutinthisresearchassesseshowforeststakeholdersinBelgiumperceivetheroleoftheirforestmanagementinthecontextofclimatechangeandtheimpedimentsthatlimittheirabilitytoprepareandrespondtothesechanges.Results:Respondentsindicatedstrongawarenessofthechangingclimate,withmorethantwo-thirds(71%)expressingconcernabouttheimpactsofclimatechangeontheirforests.However,lessthanone-thirdoftherespondents(32%)reportedmodifyingtheirmanagementpracticesmotivatedbyclimatechange.Amongthemajorconstraintslimitingtheirclimaterelatedactions,lackofinformationwasconsideredthemostimportantformanagersofbothpublicandprivateforests.Conclusions:Knowledgetransferisanessentialconditionforresearchtoleadtoinnovation.Improvingthecommunicationanddemonstrationofpossiblesolutionsforclimatechangeadaptationisthereforelikelytobethemosteffectivestrategyforincreasingtheiradoption.

简介：FOREST是活跃在当今世界乐园的一支不可多得的自然理念型音乐团体。2003年，DEEPFOREST的10周年纪念合辑，在合辑的封面，可以看到醒目的标题“ESSENCEOFFOREST”。

简介：因为他们说明大量陆上的碳存储和生产率，热带森林在减轻气候变化起一个关键作用。然而，有许多无常，与碳动力学的评价联系。我们沿着一个斜坡估计了森林结构和碳动力学(17.3跱<

简介：选用层次结构的层次分析法作为数学工具，对山西省秋千沟林场的林种和树种结构进行了研究．结果表明：该法对于“目标结构比较复杂，缺乏必要数据的结构优化问题”比较适用，可按兼顾生态效益、社会效益和经济效益，又要有所侧重的原则，将各林种、树种的面积比例落实到合理的水平上．更多还原

简介：arbuscularmycorrhizal(AM)的生物多样性殖民和AM真菌的孢子在根和相思树阿仙药(L.f)的根围土壤被学习。野，一。mangiumWilld，AnthocephalacadambaMiq，ArtocarpuschaplashaRoxb，ChickrassiatabularisA。法，Swieteniamacrophylla国王，TectonagrandisL。从种植园；Albiziaprocera(Roxb)Benth，一。falcatariaL.，Alstoniascholaris(L.)R。Br，Aphanamixispolystachya(墙)帕克，Hydnocarpuskurzii(国王)Warb，HeyneatrijugaRoxb，Lagerstroemiaspeciosa(L.)Pers.，Messuaferrea悬崖，罗汉松属nerifolia唐，Swintonia花束玫瑰Griff，Syzygiumfruticosum(Roxb)DC，S。grandis(Wt)Wal。从森林和A的托儿所幼苗。polystachya，一。chaplasha，GmelinaarboreaRoxb。并且S。来自Hazarikhil森林的cuminii(L.)Skeels，孟加拉国的Chittagong。根在苯胺蓝色被染色，根围土壤被湿sieving和移注的方法估计。AM殖民的范围在种植园样品从10%73%显著地变化了。最大的殖民在A被观察。mangium(73%)和最小的殖民在C被观察。tabularis(10%)。小囊的殖民是在五种植园树种的记录15%67%。最高在A。cadamba(67%)并且最低在T。grandis；A。chaplasha和C。tabularis没显示出小囊的殖民。Arbuscular殖民是在四种植园树种的记录12%60%。最高在A。mangium(60%)并且最低在A。cadamba。Artocarpuschaplasha的根，C。tabularis和T。grandis没显示出arbuscular殖民。在12森林树种类之中，九树种显示出AM殖民。最高在A。falcataria(62%)并且最低在S。fruticosum(10%)。在小囊的殖民的重要变化在七森林树种被记录。最高在H。trijuga(52%)并且最低在L。speciosa(18%)。Hydnocarpuskurzii，M。ferrea，P。nerifoliaS。fruticosum和S。grandis没显示出小囊的殖民。Arbuscular殖民在七森林树种被记录。最高在A。falcataria(60%)并且最低在A。procera(10%)。所有托儿所幼苗证明AM殖民和�

简介：Background:ThiscontributionevaluatestheeffectofforeststructureandtreespeciesdiversityonplotproductivityandindividualtreegrowthintheuniqueKnysnaforestsinSouthernAfricausingmappedtreedatafromanobservationalstudythathasbeenre-measuredoveraperiodof40years.Methods:Theeffectsoftreespeciesdiversityandforeststructureontreegrowthandforestproductionareevaluatedonthreelevelsofresolution:a)theforestcommunity(canopy,sub-canopyspecies),b)thesubplots(numberoftreesperha,skewnessofthediameterdistribution,diametercoefficientofvariation)andc)theimmediateneighborhoodofselectedreferencetrees('Mingling','Dominance',Aggregation'and'SizeVariation').Results:Ananalysisofthecommunitylevelidentifiedtwodistinctclusters,oneincludingdominant/canopyspecieswiththehighestgrowthratesandagreatervariationofgrowth,andanotherclusterwhichincludestheremainingsubcanopyspecieswhichhaveasmallermaximumsizeandlowerratesofgrowth.Thearea-basedstructurevariablesonplotlevelhaveahighlysignificanteffectontotalbasalareagrowth.However,theeffectsofforestdensityandspeciesrichnessonproductivitywerenotstraightforward.Maximumbasalareaproductionofabout0.75m~2/ha/yearisachievedatmediumlevelsofrichness(around20speciesperha)andmediumlevelsofdensity(around30m~2/habasalarea)usingpercentileregressionestimates.Therelative'Dominance'ofaselectedreferencetreehadahighlysignificanteffectonindividualtreegrowthonallinvestigatedspecies.Otherneighbourhoodstructurevariableswereonlyoccasionallysignificantornotsignificantatall.Conclusion:Thiscontributionpresentsanewtheoreticalframeworkforanalysingnaturalforeststhatincludescommunity,plotandneighborhoodvariablesofforeststructureanddiversity,andafirstspecificanalysisofthestructureanddynamicsoftheKnysnaAfromontaneForest,basedonauniquesetoflongtermobservations.Thespecies-area(SAR

简介：TheYangtzeRiveristhelargestriverinChina,about6,300kilometreslongwithadrainageareaandpopulationaccountingfor18.8percentand33percentrespectivelyinChina.AimingatincreasingforestandvegetationareasonthemiddleandupperreachesoftheYangtzeRivertocontrolwaterandsoilerosion,theChinesegovernmentin1989decidedtocommenceaconstructionprojectfortheprotectionoftheforestsystemonthemiddleandupperreachesoftheYangtzeRiver.Theprojectcovers645counties(citiesanddistricts)in13provinces,

简介：www.forestecosyst.comAimsandScopeForestEcosystemsisaninternationalOpenAccessjournalpublishingscientificcommunicationsfromanydisciplinethatcanprovideinterestingcontributionsaboutthestructureanddynamicsof'natural'and'domesticated'forestecosystems,andtheirservicestopeople.Wewelcomeinnovativescienceaswellasapplication