简介：WidespreadspeculationaboutChina’srecent"loggingban"notwithstanding,majorreversalsinforestrypracticesinTibetseemunlikelytomaterializeinthenearfuture.BecauseofficialsfromtheTibetAutonomousRegion(TAR)didnotsubmitaproposaltothecentralgovernmenttobeinclud...

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简介：在每个分解阶段的森林土壤性质上的崽秋天和它的效果在热带季风被调查三种植园(7年的相思树种植园，15年的相思树种植园和18年的混合种植园)和从孟加拉国的Chittagong多山的区域的一个自然森林(Sitapahar森林)的气候的条件。结果证明有机物的全部的累积与种植园年龄增加了，与年度累积率的减少伴随。在一样的植被类型以内，有山上的显著地改变的腐植质(p≤0.05)的新鲜、部分分解的垃圾的器官的累积放，在底部斜坡上是最高的并且在森林里向山顶逐渐地减少。在土壤有机物的累积的反向的趋势在15年的相思树auriculiformis种植园，燃料木头在哪儿收集了被显示出。在7年、15年的相思树和18年的混合宽广离开的种植园，全部的有机物生产由组成评价新鲜，在土壤的部分并且完全分解的垃圾以及合并有机物是2554.31，705.79和1028.01kg·h−1·a−1,分别地，并且从新鲜垃圾的相应贡献是38.23，19.40和30.48kg·h−1·a−1,分别地。在三种植园和自然森林，在一般水准上，新鲜垃圾组成了32.45%，部分与腐植质13.50%分解了垃圾并且合并了在有0.90厘米的吝啬的崽厚度的土壤54.56%全部的有机物生产的有机物。土壤酸味随有机物的分解舞台的增加增加了。

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简介：TheshortfalloftimberresourceinChinaconstantlykeepsabout150millionm3,whichmainlyreliesonimporttofillinthegap.However,Russia,thekeytimbersupplystateofChina,hasencouragedthedevelopmentofitsnationalintensivetimberprocessingandthereforetheRussianFarEastRegionstartedtograduallyrestrictlogexport.Tothisend,thispaperanalyzesthesituationofforestindustryandtimberproductioninRussianFarEastanddiscussesthecurrentstatusandexistingproblemsintimbertradebetweenRussianFarEastandChina.Attheend,thepaperpresentspolicyrecommendationforfuturetimbertradebetweenRussianFarEastandChinaandviewstheirforestrycooperationprospect.

简介：ThisarticleanalyzesthefactorsshapingcommercialtimberprofitdistributioninChina’sSouthernCollectiveForestRegion(hereinafterSCFR).Thearticlefirstdescribesthesettinganddistributionofanationalharvestquotaandanalyzesitsequityimpactsonfarmerhouseholds.Basedonaccessmappingofthecommercialtimbercommoditychain,profitdistributionandmechanismsforcontrollingandmaintainingaccesstoprofitareanalyzedfordifferentactorsalongthechain.Thedatashowthatfarmersdonotbenefittoagreatextentfromthecommerce,eveniftheyareendowedwithrightstomanageandharvestforestsandfreelysellcommercialtimberintheregion.Thereareanumberofinstitutionalandnon-institutionalfactorsthatdeterminetheextentofbenefitsfarmersandotheractorsalongthetimbercommoditychaincanseek.Undercurrentarrangements,thedevolutionofforestpropertyintheSCFRdoesnotensurethatfarmerhouseholdsbenefitfromcommercialtimbermarketing.Inordertostimulatefarmers’enthusiasmforforestrehabilitationandmanagement,beyondthedevolutionofforestproperty,itisfirstlynecessarytotakeeffectivemeasurestoimprovefarmeraccesstocommercialtimberprofits.

简介：ThisstudywasconductedintheHuoditangnaturally-regeneratedforest,whichislocatedatthecenterofthenaturalforestregionacrossthesouthern-slopeoftheQinlingMountains.Rainwaterandstreamwatersampleswerecollectedmainlyinrainyseasonsinthearea.ThesamplepHvaluesandchemicalconcentrationsweremeasured.Theresponseofstreamwaterchemistrytorainwateracidificationintheregionwasstudied.TheresultsshowedthatlongtimerainwateracidificationcouldresultinreductionofpHvalue,Ca2+andMg2+concentrationinthestreamwater.ThechangesofK+,Na+concentrationofstreamwaterwerenotcorrelatedwiththerainwateracidification.TherewasnoresponseofZn,PbandCdconcentrationofthestreamwatertorainwateracidification.Theacidifiedrainwaterdidnotresultinthereleaseoftheheavymetalsenrichedintheforestsoil.

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。

简介：Saturatedhydraulicconductivity(Ks)isanimportantsoilhydraulicparameterforcharacteringtherateofwaterflowacrossthesoilsandismainlyrelatedtoitshighspatialvariability.Inasmallwatershedwiththeareaof0.27km2intheLoessPlateau,Ksof197soilsamplesunderdifferentvegetationsandlandformsweremeasured.Kshadamoderatevariabilityfortotalsamples.TheforestlandhadhighKswithlowcoefficientofvariation(CV),butthegrasslandinthewatershedbottomhadlowKswit...

简介：Exclosureisamethodofrehabilitatingdegradedlandsbyprotectingthemfromtheinterferenceofanimalsandfromhumanencroachment,andisusedtoregeneratenativevegetationasawaytoreducesoilerosion,increaserainwaterinfiltrationandprovidefodderandwoodybiomassindegradedgrazinglands.Therefore,westudiedwoodyplantstructure,diversityandregenerationpotentialsin5-and10-yeargrazingexclosuresincomparisonwithopengrazedsitesinasemi-aridenvironment.Dataonspeciesdiversity,abundance,structure,basalarea,frequency,density,andregenerationstatuswerecollectedfrom270sampleplots.Forty-onewoodyspeciesrepresenting20familieswereidentified,with18,28and38speciesfoundinopengrazedareas,andin5-and10-yeargrazingexclosures,respectively.The10-yeargrazingexclosureshadahigher(P<0.05)speciesrichnessandplantdensitiescomparedtothe5-yeargrazingexclosuresandtheopengrazedareas.ThepopulationstructureandregenerationstatusofwoodyspeciesinbothgrazingexclosuresshowedaninvertedJ-shape,indicatingahealthyregenerationstatus,whereashamperedregenerationwasobservedinopengrazedareas.Theestablishmentofgrazingexclosureshadpositiveeffectsinrestoringwoodyplantdiversityandimprovingvegetationstructureandregenerationpotentialsofdegradedgrazinglands.

简介：ThehumidagroclimaticconditionsofKerala,IndiapermitthecultivationofanarrayofbamboospeciesofwhichDendrocalamusstrictusRoxb.(Nees.)isanimportantoneonaccountofitshighgrowthrateandmultipleuses.Standdensity,apotentialtoolincontrollingtheproductivityofwoodyecosystems,itseffectongrowthandrootdistributionpatternsmayprovideabetterunderstandingofproductivityoptimizationespeciallywhenbamboo-basedintercroppingoptionsareconsidered.Growthattributesof7-year-oldbamboo(D.strictus)standsmanagedatvariablespacing(494m,696m,898m,10910m,12912m)werestudied.Functionalrootactivityamongbambooclumpswerealsostudiedusingaradiotracersoilinjectionmethodinwhichtheradioisotope32Pwasappliedtosoilatvaryingdepthsandlateraldistancesfromtheclump.Resultsindicatethatspacingexertsaprofoundinfluenceongrowthofbamboo.Widelyspacedbambooexhibitedhigherclumpdiametersandcrownwidthswhileclumpheightswerebetterundercloserspacing.Clumpheightwas30%lowerandDBH52%higheratthewidestspacing(12912m)comparedtotheclosestspacing(494m).Withincreasingsoildepthandlateraldistance,rootactivitydecreasedsignificantly.Rootactivityneartheclumpbasewashighest(809countsperminute,cpm;50cmdepthand50cmlateraldistance)at494m.Tracerstudyfurthershowedwiderdistributionofrootactivitywithincreaseinclumpspacing.Itmaybeconcludedthattheintensiveforagingzoneofbambooiswithina50-cmradiusaroundtheclumpirrespectiveofspacing.N,PandKcontentintheupper20cmwas2197,21,and203kg/harespectivelyforthecloselyspacedbamboo(494m)whichweresignificantlyhigherthancorrespondingnutrientcontentatwiderspacings.About50%ofN,PandKwerepresentwithinthe0-20cmsoillayer,whichdecreaseddrasticallybeyondthe20cmdepth.Theresultssuggestthatstandmanagementpracticesthroughplantingdensityregulationcanmodifyt

简介：更好在土壤上理解森林继任的效果微生物引起的活动，土壤的比较微生物引起的性质和营养素在代表自然森林继任chronosequence的三种森林类型之间被进行。学习比较了松(Pinusmassoniana)森林(P松和阔叶烟草混合了的F),森林(MF)并且一常绿树阔叶烟草森林(BYingzuijie生物圈储备地的F),，湖南省，中国。结果显示出那土壤在MF和BF阴谋比在PF阴谋。在微生物引起的生物资源碳的范围与B有最大的价值的F，5221022?mg?kg1,由MF368569?mg?kg1,并且最后，PF193449?mg?kg1。土壤营养素更强烈比基础呼吸或新陈代谢的商与微生物引起的生物资源碳被相关。总的来说，在学习地点的森林继任改善了玷污微生物引起的性质并且玷污富饶，它能接着增加主要生产率和碳隐遁。

简介：一个总数3611真菌孤立从在季风，冬季和夏天期间从7药用的植物孵化的4200个叶片断被恢复季节。这些真菌孤立属于teleomorphicAscomycota(23.5%)，生产conidiomata(17.4%)的歪像的Ascomycota，没有conidiomata(46.9%)的歪像的Ascomycota，Zygomycota(1.42%)和无菌的形式(10.6%)。Chaetomiumglobosum，曲霉属菌尼日尔，Aureobasidiumpullulans，Curvularialunata，镰刀霉spp，毛丛spp，Pestalotiopsisspp，Trichodermaviridae，Cladosporiumcladosporioides，经常从超过一主人植物被孤立。endophytic的数字孤立比在季风和夏天季节在冬季是更高的。

简介：ThetaigaconiferousforestsoftheSiberianregionarethemaincarbonsinksintheforestecosystems.Quantitatively,thesizeofthecarbonaccumulationisdeterminedbythephotosyntheticproductivity,whichisstronglyinfluencedbyenvironmentalfactors.Asaresult,anassessmentoftherelationshipbetweenenvironmentalfactorsandphotosyntheticproductivitymakesitpossibletocalculateandevenpredictcarbonsinksinconiferousforestsattheregionallevel.However,atvariousstagesofthevegetativeperiod,theforceoftheconnectionbetweenenvironmentalconditionsandtheproductivityofphotosynthesismaychange.Inthisresearch,correlationsbetweenthephotosyntheticactivityofScotspine(PinussylvestrisL.)withtheenvironmentalconditionswerecomparedinspringandinautumn.Inspring,closepositivecorrelationofthemaximumdailynetphotosynthesiswasidentifiedwithonlyoneenvironmentalfactor.Fordifferentyears,correlationswereforsoiltemperature(rs=0.655,p=0.00315)oravailablesoilwatersupply(rs=0.892,p=0.0068).Inautumnwithindifferentyears,significantcorrelationwasshownwithtwo(temperatureofairandsoil;rs=0.789and0.896,p=0.00045and0.000006,respectively)andfourfactors:temperatureofair(rs=0.749,p=0.00129)andsoil(rs=0.84,p=0.00000),availablesoilwatersupply(rs=0.846,p=0.00013)andirradiance(rs=0.826,p=0.000001).Photosyntheticactivityhasaweakerconnectionwithchangesinenvironmentalfactorsinthespring,ascomparedtoautumn.Thisisexplainedbythemultidirectionalinfluenceofenvironmentalconditionsonphotosynthesisinthisperiodandbythenecessityofearlierphotosynthesisonset,despitetheunfavorableconditions.Thisdatamaybeusefulforpredictingtheflowofcarbonindependenceonenvironmentalfactorsinthisregioninspringandinautumn.

简介：本文研究了长江三峡花岗岩地区林地土壤流失特性．结果表明由鳞片状面蚀导致的土壤流失量月分布与月降雨量的分布趋势基本一致，二者呈现出较为明显的线性相关关系．植物盖度≥０．７０的林地土壤流失多集中发生在６～９月份，土壤流失量在５０００ｔ·ｋｍ－２·ａ－１以下．盖度＜０．７的林地土壤流失年内分布时间多在３～１０月份，土壤流失量为５００～６０００ｔ·ｋｍ－２·ａ－１．

简介：GuanngxiAutonomousRegionisanimportanttropicalforestryregioninsouthofChina.ThemainpurposeofthisresearchsupportedbyFAOistogenerateactionplanforsustainableforestrydevelopmentofthisregion.Throughtwo-yearbroadanddeepinvestigation,theprogrammeoftheactionplanthasbeenmade,whichincludes12fields,38projects,withdurationof5years.

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：这研究评估空间建模过去常估计D慤的危险的multifactorial吗？

简介：Thusfar,measurementsandestimationsofactualevapotranspiration(ET)inextremelyaridareasarestillinsufficient.BasedonsuccessiveobservationsfromJune–September2014,wesimulatedETofaPopuluseuphraticaOliv.forestduringthegrowingseasoninanextremelyaridregionofnorthwestChinausingtheShuttleworth–Wallace(S–W)model.SimulatedETvalueswerecomparedtothoseoftheeddy-covariance(EC)methodona1hinterval.Witharootmeansquareerror(RMSE),relativeerror(RE)andmeanabsoluteerror(MAE)of0.192,3.100and0.165mmh-1,respectively,modelperformancewasnotsatisfactory.Inparticular,ondayswithstrongwinds(Sep.11–13),deviationsbetweensimulatedandobservedETvaluesincreasedto0.275,0.878and0.251mmh-1,RMSE,REandMAErespectively.Thesevaluesweresignificantlygreaterthanthoseinotherstudyperiodsandweremostlikelyowingtosharpincreasesinwindspeed.Asaresult,thereweresubstantialadvectiveeffects,whichisnotconsistentwiththeassumptionoftheS–Wmodelthattherearenoadvectiveeffectsormesoscalecirculationpatternsinducedbysurfacediscontinuities.