简介：Northernpeatlandsstorealargeamountofcarbonandplayasignificantroleintheglobalcarboncycle.Owingtothepresenceofwaterloggedandanaerobicconditions,peatlandsaretypicallyasourceofmethane(CH4),averypotentgreenhousegas.ThispaperreviewsthekeymechanismsofpeatlandCH4production,consumptionandtransportandthemajorenvironmentalandbioticcontrolsonpeatlandCH4emissions.TheadvantagesanddisadvantagesofmicrometeorologicalandchambermethodsinmeasuringCH4fluxesfromnorthernpeatlandsarealsodiscussed.ThemagnitudeofCH4fluxvariesconsiderablyamongpeatlandtypes(bogsandfens)andmicrotopographiclocations(hummocksandhollows).Someanthropogenicactivitiesincludingforestry,peatharvestingandindustrialemissionofsulphurdioxidecancauseareductioninCH4releasefromnorthernpeatlands.FurtherresearchshouldbeconductedtoinvestigatetheinfluenceofplantgrowthformsonCH4fluxfromnorthernpeatlands,determinethewatertablethresholdatwhichplantproductioninpeatlandsenhancesCH4release,andquantifypeatlandCH4exchangeatplantcommunitylevelwithahighertemporalresolutionusingautomaticchambers.

简介：打区域是巴基斯坦的一个生物多样性中心。植物种类，特别树，在Swat，区域从全球气候暴露于扑灭威胁变化。用HADCM3A2a全球气候变化情形，种类分发的最大的熵(MaxEnt)建模在未来分发预言了一个可观的变化受苦pindrow(Royle前D.Don)Royle。AUC(在曲线下面的区域)0.972和0.983珍视目前是重要的，未来分发分别地种类当模特儿。象最温暖的季度(bio_10)和年度温度范围(bio_7)的吝啬的温度那样的有关生物与气候的变量显著地作出贡献到模型并且因此影响种类的预言的分发和密度，是清楚的。未来模型预言到一年，2080人口密度将显著地减少。种类的最高的密度在Sulatanr和Mankial的区域在山谷的东方、西方的边阶被记录。在种类的密度和分发的变化能有可观的影响，不是仅仅在树种类本身上，但是在联系subflora上也。

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简介：Today42%(9000km^2)oftheareaofHesseiscoveredwithforests.Thetotalareaofforestshasslightlyincreasedsinceseveralyears.ButactuallytheforestsadjacenttotheconurbationsofNorthernHesseinthevicinityofKasselinparticularandintheRhein-MainRegionsurroundingFrankfurtareinaverydifficultposition.Thereisbigdemandforlandtobeconvertedintosettlements,infrastructure,etc.,whilethereisincreasingneedfortheprotectiveandrecreationalfunctionsoftheforests.Thereforemaintenanceofexistingforestsandestablishmentofnewforestsareamongstthemostimportantresponsibilitiesoftheforestauthoritiesonregionalanddistrictlevel.

简介：Adoptionofcertifiedandimprovedhigh-yieldingcropvarietiesisimportantavenueforincreasingagriculturalproductivityandimprovingthelivingstandardofthefarmersindevelopingcountries.ThemainobjectiveofthecurrentstudywastoexaminefactorsaffectingadoptionofimprovedricevarietiesbysmallholderfarmersinNorthernSindh,Pakistan.Therandomsamplingtechniquewasusedtocollectdatafrom220smallholderricefarmersthroughthefacetofaceinterview.Datawereanalyzedusingdescriptivestatisticsandprobitregressionmodel.Theempiricalresultsshowedthatyearofeducation(P≤0.093),farmingexperience(P≤0.043),soilquality(P≤0.077),farmmachineryownership(P≤0.000),accesstomarketinformation(P≤0.055)andcontactwithextensionagents(P≤0.006)hadsignificantlypositiveinfluenceonadoptionofimprovedricevariety,whileage(P≤0.053)hadsignificantlynegativeeffect.

简介：到沿着Changbai山的北斜坡的1900m的从700m的社区的种类分发频率被在1999的夏天使用Raunkiaer的频率分析方法学习。有举起的增加的社区的作文和结构上的变化从频率的观点被显示。尽管在社区之中有差别，结果证明为包括树，灌木和植物的社区的所有种类，频率介绍了鈥淟鈥?形状。高频率种类的百分比随举起的增加增加了。作为在反映种类的重要索引之一空间模式，频率在种类的重要性上面的不仅表演，而且在社区的空间分发的平均。频率数字能在某程度揭示社区的复杂性和差异。

简介：Background:Wintermoth(Operophterabrumata)andmottledumbermoth(Erannisdefoliaria)areforestLepidopteraspeciescharacterizedbyperiodichighabundanceina7–11yearcycle.DuringoutbreakyearstheycauseseveredefoliationinmanyforeststandsinEurope.Inordertobetterunderstandthespatio-temporaldynamicsandelucidatepossibleinfluencesofweather,standandsiteconditions,ageneralizedadditivemixedmodelwasdeveloped.TheinvestigateddatabasewasderivedfromgluebandcatchmonitoringstandsofbothspeciesinCentralandNorthGermany.Fromthegluebandsonlyfemalemothindividualsarecountedandahazardcodeiscalculated.Themodelcanbeemployedtopredicttheexceedanceofawarningthresholdofthishazardcodewhichindicatesapotentialseveredefoliationofoakstandsbywintermothandmottledumberinthecomingspring.Results:Thedevelopedmodelaccountsforspecifictemporalstructuredeffectsforthreelargeecoregionsandrandomeffectsatstandlevel.Duringvariableselectionthenegativemodeleffectofpestcontrolandthepositivemodeleffectsofmeandailyminimumtemperatureinadultstageandprecipitationinearlypupalstagewereidentified.Conclusion:Thedevelopedmodelcanbeusedforshort-termpredictionsofpotentialdefoliationriskinCentralandNorthGermany.Thesepredictionsaresensitivetoweatherconditionsandthepopulationdynamics.However,afutureextensionofthedatabasecomprisingfurtheroutbreakyearswouldallowfordeeperinvestigationofthetemporalandregionalpatternsofthecyclicdynamicsandtheircausalinfluencesonabundanceofwintermothandmottledumber.

简介：Background:Thelargepotentialofthesoilorganiccarbon(SOC)pooltosequesterCO2fromtheatmospherecouldgreatlyamelioratetheeffectoffutureclimatechange.However,thequantityofcarbonstoredinterrestrialsoilslargelydependsuponthemagnitudeofSOCmineralization.SOCmineralizationconstitutesanimportantpartofthecarboncycle,andisdrivenbymanybiophysicalvariables,suchastemperatureandmoisture.Methods:Soilsamplesofapineforest,anoakforest,andapineandoakmixedforestwereincubatedfor387daysunderconditionswithsixtemperaturesettings(5°C,10°C,15°C,20°C,25°C,30°C)andthreelevelsofsoilmoisturecontent(SMC,30%,60%,90%).TheinstantaneousrateofmineralizedSOCwasperiodicallyandautomaticallymeasuredusingaLi-CorCO2analyzer.BasedonthemeasuredamountofmineralizedSOC,carbonfractionswereestimatedseparatelyviafirst-orderkineticone-andtwo-compartmentmodels.Results:Duringthe387dayincubationexperiment,accumulativemineralizedcarbonrangedfrom22.89mgcarbon(C)·g-1SOCat30°Cand30%SMCforthemixedforestto109.20mgC·g-1SOCat15°Cand90%SMCfortheoakforest.Mineralizedrecalcitrantcarbonvariedfrom18.48mgC·g-1SOCat30°Cand30%SMCforthemixedforestto104.98mgC·g-1SOCat15°Cand90%SMCfortheoakforest,andcontributedatleast80%tototalmineralizedcarbon.Conclusions:Basedontheresultsofthisexperiment,thesoilorganicmatterofthepurebroadleavedforestismorevulnerabletosoilmicrobialdegradationinnorthernChina;mostoftheamountofthemineralizedSOCderivedfromtherecalcitrantcarbonpool.Labilecarbonfractionconstitutesonaverage0.4%ofSOCacrossthethreeforesttypesandwasrapidlydigestedbysoilmicrobesintheearlyincubationstage.SOCmineralizationmarkedlyincreasedwithsoilmoisturecontent,andcorrelatedparabolicallytotemperaturewiththehighestvalueat15°C.Nosignificantinteractionwasdetectedamongthese

简介：TherestorationofforestlandscapehasdrawnmuchattentionsincethecatastrophicfiretookplaceonthenorthernslopeofGreatXing'anMountainsin1987.Forestcanopydensity,whichhascloserelationtoforestproductivity,wasselectedasakeyfactortofindhowmuchtheforestqualitywaschanged13yearsafterfire,andhowfireseverity,regenerationwayandterrainfactorsinfluencedtherestorationofforestcanopydensity,basedonforestinventorydatainChina,andusingKendallBivariateCorrelationAnalysis,andDistancesCorrelationAnalysis.Theresultsshowedthatfireseveritywhichwasinverselycorrelatedwithforestcanopydensitygradewasaninitialfactoramongallthatselected.Regenerationwaywhichdidnotremarkablyaffectforestcanopydensityrestorationinshortperiod,mayshortenthecycleofforestsuccessionandpromotetheforestproductivityofconophoriuminthefuture,Amongthethreeterrainfactors,theeffectofslopewasthestrongest,thepositiononslopewasthesecondandtheaspectwasthelast.

简介：Remote-sensingdataforprotectedareasinnorthernTogo,obtainedinthreedifferentyears(2007,2000,and1987),wereusedtoassessandmapchangesinlandcoverandlanduseforthisdroughtpronezone.Thenormalizeddifferencevegetationindex(NDVI)wasappliedtotheimagestomapchangesinvegetation.Anunsupervisedclassification,followedbyclassesrecoding,filtering,identifications,areacomputingandpost-classificationprocesswereappliedtothecompositeofthethreeyearsofNDVIimages.Maximumlikelihoodclassificationwasappliedtothe2007image(ETM+2007)usingasupervisedclassificationprocess.Sevenvegetationclassesweredefinedfromtrainingdatasets.Thesevenclassesincludedthefollowingbiomes:riparianforest,dryforest,floodedvegetation,woodedsavanna,fallows,parkland,andwater.Fortheseclasses,theoverallaccuracyandtheoverallkappastatisticfortheclassifiedmapwere72.5%and0.67,respectively.Dataanalysesindicatedagreatchangeinlandresources;especiallybetween1987and2000probablyduetotheimpactofdemocratizationprocesssocial,economic,andpoliticaldisorderfrom1990.Wide-scalelossofvegetationoccurredduringthisperiod.However,areasofvegetationclearingandregrowthweremorevisiblebetween2000and2007.Themainsourceofconfusioninthecontingencymatrixwasduetoheterogeneitywithincertainclasses.Itcouldalsobeduetospectralhomogeneityamongtheclasses.Thisresearchprovidesabaselineforfutureecologicallandscaperesearchandforthenextmanagementprograminthearea.

简介：AfieldexperimentwasconductedatKezuohouqiCounty,InnerMongoliaAutonomousRegionofChina,whichwaslocatedonthesoutheasternedgeoftheHorqinSandyLand,tostudythespatialvariabilityofsoilnutrientsforasmallscale,nutrient-poor,sandysiteinasemi-aridregionofnorthernChina;toinvestigatewhetherornottherewere'islandsoffertility'attheexperimentalsite;andtodeterminethekeynutrientelementsthatsustainedecosystemstability.Resultsobtainedfromgeostatisticalanalysisindicatedthatthespatialdistributionpatternofsoiltotalnitrogen(STN)wasfardifferentfromthoseofsoilorganicmatter(SOM),totalphosphorus(STP),andtotalpotassium(STK).ComparedtoSOM,STP,andSTK,STNhadalowerstructuralheterogeneityratioandalongerrange,whileotherelementswereallsimilar.Inaddition,STNhadanisotropicspatialstructure,whereastheothershadananisotropicspatialstructure.Thespatialstructurepatternsofherbagespecies,cover,andheightalsodiffered,indicatingthatspatialvariabilitywassubjectedtodifferentecologicalfactors.Differencesinthespatialvariabilitypatternsamongsoilnutrientsandvegetationpropertiesshowedthatsoilnutrientsforasmall-scalewerenottheprimarylimitingfactorsthatinfluencedherbagespatialdistributionpatterns.Incorporatingspatialdistributionpatternsoftreespecies,namely,Pinussylvestrisvar.mongolicaLitv.andshrubLespedezabicolorTurcz.inaresearchplotandusingfractaldimension,SOM,STP,andSTKwereshowntocontributetothe'islandsoffertility'phenomenon,howeverSTNwasnot,possiblymeaningthatnitrogenwasakeylimitingelement.Therefore,duringrestorationofsimilarecosystemsmoreattentionshouldbegiventosoilnitrogen.

简介：Background:Forestmanagementdecisionsarebasedonexpectationsoffuturedevelopments.Forsounddecisionsitisessentialtoaccuratelypredicttheexpectedvaluesinfuturedevelopmentsandtoaccountfortheirinherentuncertainty,forexampletheimpactofclimatechangeonforests.Changingclimaticconditionsaffectforestproduaivityandaltertheriskprofileofforestsandforestenterprises.IntensifyingdroughtstressisseenasonemajorriskfactorthreateningforestmanagementinthenorthGermanlowlands.Droughtstressreducestreegrowthandvitalityandmighteventriggermortality.Butsofar,itisnotpossibletoquantifyeffectsofapersistentdryerclimateonforestproductivityatalevelsuitableforforestmanagement.Methods:Weapplyawell-establishedsingle-treeforestgrowthsimulatortoquantifytheeffectofpersistentdryerclimatesonfutureforestproductivity.WeanalysethegrowthofScotspine(PinussylvestrisL.);Europeanbeech{FagussylvoticoL.)andoak{QuercusroburL.andQuercuspetraeo(Matt.)Liebl.)intwoforestregionsinthenorthGermanlowlandsforatimeintervalof60yearsuntil2070.Thegrowthresponseunderthreedifferentclimateprojectionsiscomparedtoabaselinescenario.Results:Theresultsshowcleardifferencesinvolumeincrementtopersistentdryerclimatesbetweentreespecies.Thefindingsexhibitregionaldifferencesandtemporaltrends.WhilemeanannualincrementatbiologicalrotationageofScotspineandoakpredominantlybenefitsfromtheprojectedclimateconditionsuntil2070,beechmightsufferlossesofupto3m3-ha’-yr1dependingonclimatescenarioandregion.However,intheprojectionperiod2051to2070theuncertaintyrangescomprisepositiveaswellasnegativeclimaticeffectsforallspecies.Conclusions:Theprojectedchangesinforestgrowthserveasquantitativecontributionstoprovidedecisionsupportintheevaluationof,forexample,speciesfuturesitesuitabilityandtimbersupplyassessments.Theanalysiso

简介：在modulating植物生产率的土壤pH的潜在的角色根据干燥质量被估计，在0.25m2空铅形式收获了，在北希腊的二块低生产率的高地草地使遭到了到年度因素的氮(N)和磷(P)授精(15gNm−2year−1和10gPm−2year−1)在最小上3年的时期。在这些特别条件下面，一种积极关系将在土壤pH和植物生产率之间存在，进一步，营养素的那N或P化肥应用限制系统，这被假设，将导致一变弱这种积极关系。一种重要积极关系在其它在二个学习区域和一个积极趋势之一在土壤pH和植物生产率之间被证实。而且，植物生产率增加，后面的授精，看起来在土壤pH植物生产率关系上有有害效果。调查结果支持原来的假设并且加强想法种调停差异的土壤pH植物生产率关系是发生在更多的“typical”下面的更强烈的植物种形成的结果更高的pH在的土壤条件与热带区域对比适度。

简介：RicecropgrowthandyieldinthenorthIranareaffectedbycropdurationandphenology.ThepurposeofthisstudywastocalibrateandvalidatetheORYZA2000modelunderpotentialproductionbasedonexperimentaldataforsimulatingandquantifyingthephenologicaldevelopment,cropdurationandyieldpredictionofricecropinfluencedbydifferentseedlingages.InordertocalibrateandvalidatethecropparametersofORYZA2000model,atwo-yearfieldexperimentwasconductedunderpotentialgrowthconditio...

简介：我们检验了本地社区刺激节目在Baneh城市里在三个forested村庄里改进传统的森林管理，西方的伊朗的北Zagros森林里的库尔德斯坦省。Zagros森林盖住607万哈并且支持富人植物和动物差异。在本地社区聚会和经济系统和传统的森林管理的无效的变化在最近的十年在森林新生的稳定性导致了一种批评状况。由于缺乏生产并且可耕地和产生失业和贫穷，人overexploitedZagros森林。在传统的森林管理的外面的干预创造在本地民族和森林管理组织之间的冲突。为了完成持续森林管理，包括的森林资源保存和自然资源的改进，基于社区的生计，基于森林的重要函数实现林地刺激程序(FIP)是合乎需要的。社区，本地生计上的森林的效果，和从森林提取的产品的表的socio-economics的详细信息不过从本地社区的调查被获得问询表，会见和观察。我们在三个村庄里学习了276个家庭并且在定量分析由业主完成了76张问询表。采样被简单随机的采样(SRS)执行。农村社区的需要例如家畜耕作，主要从特征和村庄的环境特征产生。我们识别了驱动力，压力，地位，影响和回答(DPSIR)设计刺激节目，由DPSIR分析和相互作用分析。来自森林的本地社区好处的评估显示了那以便改进森林管理，319美元将被每个家庭在2010作为刺激每年需要阻止砍并且收集的柴，森林降级的主要原因。

简介：Arbuscularmycorrhizafungi(AMF)arevitalintheregenerationofvegetationindisturbedecosystemsduetotheirnumerousecologicaladvantagesandthereforearegoodindicatorsofsoilandecosystemhealthatlarge.Thisstudywasaimedatdetermininghowtheseasonal,vegetationcoverdensity,edaphicandanthropogenicfactorsaffectAMFrootcolonization(RC)andsporedensity(SD)inDesa’adryAfromontaneforest.AMFRCandSDintherhizosphereoffivedominantwoodyspecies,Juniperusprocera,Oleaeuropaea,Maytenusarbutifolia,CarissaspinarumandDodonaeaangustifoliagrowinginDesa’aforestwerestudiedduringtherainyandthedryseasonsinthreepermanentstudyvegetationcoverdensityplots(dense,medium,andpoor).Eachplot(160×40m2)hastwomanagementpractices(fencedandunfencedplots)ofarea.A100gsampleofrhizospheresoilfrommoisturefreecompositesoilwasusedtodeterminesporedensity.Sporedensityrangedfrom50to4467spores/100gsoil,andallspecieswerecolonizedbyAMFwithinarangeof4–95%.Glomuswasthedominantgenusintherhizosphereofallspecies.VegetationcoverdensitystronglyaffectedSDandRC.TheSDwassignificantlyhigher(p<0.05)inthepoorvegetationcoverdensitythanintheothertwoandlowestinthedensecover;rootcolonizationshowedthereversetrend.Managementpracticessignificantly(p<0.05)influencedAMFSDandRC,withthefencedplotsbeingmorefavoured.Seasonssignificantly(p<0.05)affectedRCandSD.MoreRCandSDwereobservedinthewetperiodthanthedryperiod.CorrelatingAMFSDandRCwithsoilphysicalandchemicalpropertiesshowednosignificantdifference(p>0.05)exceptfortotalnitrogen.Disturbance,vegetationcoverdensity,seasonandtotalnitrogenaresignificantfactorsthatcontrolthedynamicsandmanagementinterventionstomaintaintheforesthealthofdryAfromontaneforests.

简介：Background:Aftertheirdeath,Scotspinetreescanremainstandingfordecadesandsometimesupto200years,forminglong-lastingandecologicallyimportantstructuresinborealforestlandscapes.Standingdeadpinesdecayveryslowlyandwithtimedevelopinto‘kelo'trees,whicharecharacterizedbyhardwoodwithsilvery-coloredappearance.Thesekelotreesrepresentanecologicallyimportant,longlastingandvisuallystrikingelementofthestructureofnaturalpine-dominatedforestsinborealFennoscandiathatisnowadaysvirtuallyabsentfrommanagedforestlandscapes.Methods:Weexaminedandmappedtheamount,structuralfeatures,sitecharacteristicsandspatialdistributionofdeadstandingpinetreesoveratenhectareareainanunmanagedborealforestlandscapeintheKalevalaNationalParkinRussianVienaKarelia.Results:Themeanbasalareaofdeadstandingpinetreesintheforestedpartofthelandscapewas1.7m~2?ha~(-1)andtheestimatedvolume12.7m~3?ha~(-1).Fromthetotalnumberofstandingdeadpinetrees65%werekelotrees,withabasalareaof1.1m~2?ha~(-1)andvolumeof8.0m~3?ha~(-1),theremainderconsistingofstandingdeadpinesalongthecontinuumbetweenarecentlydeadtreeandakelotree.Overall,standingdeadpinesweredistributedthroughoutthestudyarea,buttherewasatendencytowardsspatialclusteringupto<100mdistances.Standingdeadpinesweremostcommonlysituatedonflatgroundorinthemidslopeinthelocaltopography.Inaddition,standingdeadpinescontributedtosubstratediversityalsobycommonlyhavingcharredwoodandbrokentops.Basedonthepresenceofdeadpinesnagsindifferentstageoftransitionfromarecentlydeadpinetoakelowithsilverysurface,itseemsevidentthattheprocessofkelorecruitmentwascontinuouslyinactioninthestudiedlandscape.Conclusions:Kelotreesareanomnipresentfeatureinnaturalpine-dominatedforestlandscapeswithimportantcontributiontoforeststructuralandsubstratediversity.Becauseo