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简介：Addinglowmolecularweightresinsintowoodcanovercomewoodintrinsicdefects,whichisanewapproachforthehighefficientutilizationofplantation.Thispaperreviewstheresearchesonlowmolecularweightresinsmodifyingwood,includingdifferentimpregnatingresins,impregnationtechnologies,propertiesoftreatedwoodandmechanismofmodifyingwood.Intheend,somesuggestionsandprospectsareputforward.

简介：Thehistoricdevelopmentofforestcertificationwasfirstlyreviewedinordertounderstandhowforestcertificationhasdevelopedthroughouttheworld.Thecharacteristicsofforestcertificationwereanalyzedindetails,includingtheessenceofforestcertification,approachofforestcertification,structureofforestcertificationanddevelopmentprocessesofforestcertificationstandards.Then,theforestcertificationdevelopmentinChinawasreviewed,includingbackground,basicprinciplesandobjectivesandmaintasks.Basedonthereviewsonforestcertification,recommendationsweregivensoastogreatlyboostthedevelopmentofforestcertificationinChina.

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

简介：Theecogeomorphicprocessesoccurringonsemiaridrangelandsarereviewed,withemphasisonthesource-sinkrelationsandpositivefeedbackloopsthatexistedbetweenshrubpatchesandintershrubareas,andthewaylivestockpresenceaffectedtheseinteractions.Comparedwithintershrubareas,theshrubpatcheshadahighersoilporosity,infiltrationcapacity,water-holdingcapacity,hydraulicconductivity,structuralstability,andorganicmattercontent,andlowerbulkdensity.Thesedi?erencesderivedfromahostofprocesseswhoseintensitywaslessintheshrubpatches,includingraindropimpact,mechanicalcrustformation,overlandwaterflow,soilerosion,evaporativemoistureloss,andflocktrampling.Therewasalsogreatershadingofthesoilsurface;soilandlitterdeposition;wateraccumulation;microbial,fungal,andmesofaunalactivitiesintheshrubpatches.Theoverlandflowofwatercarriedsoilandlitterfromtheintershrubareastotheshrubpatchesandresultedinmicrotopographicmodificationsthattendedtostrengthenthesesource-sinkrelations.Grazinghadanimpactontheseprocesses,notonlyattheshrub-intershrubscalebutalsowithintheintershrubareas,throughthecreationofhighlycompactedtramplingroutes.Thecombinedroleoftheaboveecogeomorphicprocesseswastomaintaintherangeland’sfunctionality.Withouttheseinter-relationships,waterloss,soilerosion,andnutrientdepletionwouldoccuratthehillsidescale,causingdegradationofthelandscape.

简介：Asanimportambio-resource,insectresourceshavenotbeenputintofullplayashealthyfood.Basedonstudyandanalysis,thenutritivevalueofedibleinsectswasreviewed.Theresultsshowedthatinsectshaverichprotein(20%-70%),aminoacid(30%-60%),fat(10%-50%),fattyacid,carbonhydrate(2%-10%),mineralelements,vitaminsandotheractivatedelementswhicharegoodforhuman'shealth.Asproteinresources,thenutritivevalueofedibleinsectsisasgoodasanimalandplantresources.Insec...

简介：ForestpolicyevolutionwaspresentedfirstlyinordertounderstandthebackgroundofforestpolicydevelopmentinChina.Therecentchangesofforestpolicywereintroducedindetails,includingforestpoliciesonimprovingbiodiversityconservationandsecuringnationalecologicalsafety,restoringkeyecosystems,promotingsustainableforestmanagement(SFM),clarifyingforestlandtenureandprotectingfarmer’srightonforestandforestlandmanagement,promotinghealthyforestryindustrydevelopment...

简介：很多新变化，特别杂交稻，自从1998，在中国被开发了并且释放。收益潜力和杂交稻的谷物质量也为也包括indica和装饰用的梨树类型的三线、较普通活字大一倍的杂交稻两个都显著地被改进了。自从1986，在中国的米饭变化的扩展上的趋势被新变化的增加的数字标记，减少年度种区域每变化，有一个大规模延期区域的变化的减少的数字，当更新率和有跨provincial扩展的核心变化的比例仍然保持未改变时。Thiscurrent主要问题和米饭在中国繁殖和延期的未来目标也被讨论。

简介：Byreviewsoftherelatedpapersandworksabouturbangreenspacesystemplanningathomeandabroad,thepaperdefinedtheconceptandclassificationofurbangreenspacesystem,andfunctions,tasks,structureandlayoutofgreenlandsystemplanning.Inthemeantime,thepaperintroducedrelatedtheory,reviewedthedevelopmentandcurrentsituationofdomesticgreenlandsystem,andfinallyforecastedthedevelopmenttrends.

简介：土壤体积密度的测量为理解土壤的物理、化学、生物的性质是重要的。精确、快速的土壤体积密度测量技术在农业试验性的研究起一个重要作用。这评论是存在测量方法的一篇全面摘要并且为未来开发评估他们的优点，劣势，错误的潜在的来源，和方向。这些技术能广泛地作为直接、间接的方法被分类。直接方法包括核心，土块，和挖掘采样，而间接方法包括放射和回归途径。核心方法最广泛地被使用，但是为采样使用多重土壤深度耗时、困难。coring柱体的尺寸使用了，操作员经验，采样深度，并且在原处显著地玷污潮湿内容影响它的精确性。土块方法是合适的因为有重黏土的使用，和它的精确性依赖于设备刻度，弄干时间，和操作员经验，但是这个过程复杂、耗时。挖掘技术最通常被用来评估森林土壤的体积密度，但是把他们不能与大毛孔在土壤被使用，他们的测量精确性被土壤质地和分析的类型强烈影响的主要限制选择。间接方法看起来比直接途径有更大的精确性，但是有更高的费用，是更复杂的，并且要求更大的操作员经验。一如此的途径使用gamma放射，和它的精确性被土壤深度强烈影响。当他们能做间接大小，回归方法是节俭的，但是这些取决于土壤质地和有机物内容和地理、气候的性质的好、优秀数据。另外，它的精确性象大多数另外的途径一样，与采样深度减少。

简介：油喷洒与油的不断增长的资源利用，交通，存储，和意外的漏在冷环境成为了一个严重问题。包括物理、化学、生物的方法，几种技术被用来从环境恢复流出的油。自从它在与不太过度的环境损坏移开油有效、经济，Bioremediation是为补习的一种有希望的选择。然而，它是在冷区域的一个相对慢的过程，成功的度取决于很多个因素，包括在冷环境，和微生物引起的专业和简历补习的环境限制流出的油的性质和命运。微生物引起的因素包括烃，通过房间膜的集体转移，和新陈代谢的限制的简历可获得性。至于在冷区域的环境限制，强调在土壤温度，结冰融化过程，氧和营养素上是可获得性，毒性，和电子领受人。有在极的区域的成功的几个盒子，特别地在北极和近北极的区域。然而，为在冷环境的简历补习的挑战和限制仍然保持大。

简介：土壤的描述水力的性质对环境管理重要；然而，直接测量土壤勤劳、费时间、昂贵，这很好被认出水力的性质。这份报纸考察作为一个其他的工具过去常估计土壤的pedotransfer功能(PTF)的发展水力的性质在最后二十年期间。象察觉到的卫星imagery/remote一样的现代土壤调查技术在开发PTF被使用了。比作机械学的途径，在物理性质之间的实验关系和水力的性质为预言土壤收到了宽偏爱水力的性质。许多PTF能在文学基于不同参量的功能被发现。很多个研究人员追求了能描述土壤的所有类型的水保留特征的通用功能，但是没有单个功能能被称为通用尽管货车Genuchten(VG)功能是广泛地采用的大多数。大多数报导参量的PTF集中于获得水保留的参数弄弯的VG(WRC)的评价。很多个物理、词法、化学的性质在PTF被用作预言者变量。通常，回归算法/技术(统计/神经的回归)被用于校准PTF。然而，有利用数据采矿技术的报告，例如，模式识别和基因算法。精制过去常让刻度改进PTF的精确性和可靠性的数据是批评的，这被推断。包括根均方差(RMSE)，许多统计索引同意索引(d)，最大的绝对错误(我)，吝啬的绝对错误(MAE)，决心的系数(r2)和关联系数(r)，被不同研究人员使用了评估并且验证PTF。这被说服是地点特定，对PTF的研究兴趣将继续直到通用PTF被开发并且验证。在未来研究，改进了方法将被要求从存在数据库提取信息。

简介：Thegeneralsteam-injectionpressingismainlyusedforproduceparticleboardsandmediumdensityfiberboard.However,itisdifficulttoproducesoftfiberboardwithdesiredstrength.However,theclosingsteam-injectionpressingthatbasedonthesteam-injectionpressingcould.Thewoodenframesealinguptheslabcouldpreventthesteamfromemittingwhenthesteaminjectedintotheslab.Thecaloricreleasedbysteamcondensationmaketheslabreachhightemperaturelevelforashortperiod.Thismethodisveryappropriateformakingthickpanelsintheory,especiallyforthesoftfiberboard.Itmakesagreatleapforwardonthehotpressingprocessthatforwood-basedpanels.Moreover,itwillbeameaningfultechnologicalbreakthroughindevelopingnewproductsandimprovingwoodutilization.

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简介：自从工业革命的开始，用pyrometallurgical过程的金属精制植物产生了铅(Pb)和镉(Cd)的巨大的排出物。作为如此的污染物质的核心目标，很多土壤现在在普遍区域上被污染，形成对世界范围的公共健康的大威胁。不同于器官的污染物质，Pb和Cd不经历化学或微生物引起的故障并且在他们的版本以后为更长的持续时间在地点保持可能。固定是一在原处使用划算的土壤修正案在污染土壤减少Pb和Cd可获得性的补习技术。在土壤环境的Pb和Cd污染与来源丰富，种形成和联系健康的焦点被考察用各种各样的土壤修正案的风险，和固定选择。通常适用并且为Pb和Cd固定的新兴的划算的土壤修正案包括磷酸盐混合物，liming，动物粪肥，biosolids，金属氧化物，和biochar。这些使不能调动的代理人能把金属污染物质或残余的转移归结为食物网(植物举起并且沥滤到表面下的水)并且他们在重金属固定的长期的可持续性需要另外的评价。

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简介：Microfibrilledcellulose(MFC)isanewkindofnanoscalecellulosefunctionalmaterials,havingbroadapplicationprospectsinmanyfieldslikefood,medicine,cosmetic,paint,paperandpulpengineering,compositematerials,etal.TheresearchonMFChasbeenextensivelyconductedforthepast30yearsinsomedevelopedcountries,andevensomerelevantproductshaveappearedinthemarket.Onthecontrast,similarstudiesinChinawereratherlimited.ThispaperfirstlyintroducedthepropertiesandapplicationofMFCbriefly,andthengavemoredetaileddescriptiononthepreparationtechnologyofMFCanditsimportantperformanceindexes.SeveralsuggestionsonthefuturestudyonMFCwerealsoproposed.

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简介：Atelevatedtemperatureregimesandabundantprecipitation,mobilizationandaccretionofweatheredironoxidesarepromotedespeciallyinareducedenvironmentsinthetropics.Thismayleadtotheformationofplinthite,whichhardensirreversiblyuponrepeatedwettinganddryingtoformpetroplinthite.Theneedforthisreviewstemsfromtheseeminglydearthofinformationonthesubjectandaneedtoclarifydifferenttermsusedindescribingplinthite.Wereviewvariousresearchworksonplinthiteanditsassociatedpedogenicformsinthetropics.Furthermore,weprofferrecommendationsastothemostappropriatelandusemanagementpracticesthatcouldhelpminimisetheenvironmentalandagronomicproblemsassociatedwithplinthiteanditsrelatedpedogenicforms.Parentmaterial,temperature,seasonalityandgeomorphologyarecriticalfactorsthatinfluencesoilwaterregimewhichinturnaffectthepedogenesisofplinthite.SoilpHandmineralogyareadditionalfactorsthatcouldalsopromoteplinthiteformation.Fossilplinthicsoilsarepotentialproxiesforpalaeoenvironmentalreconstruction.Measuresusedinthemanagementofplinthicsoilsincludemechanicallybreakingthehardpansandtheuseoforganicandinorganicamendmentstomodifythestructureandchemistryofthesoils.Avoidanceofpracticesthatwouldpredisposesoilstoerosionwouldalsopreventplinthization.Wecallfortherelinquishmentoftheterm'laterite'whichisageneraltermforallformsofironoxide-enrichedearthymaterialsasusedforplinthite.PlinthichorizonshouldalsobeincorporatedintotheUnitedStatesDepartmentofAgricultureSoilTaxonomyinviewofitsgrowingimportanceinsoils.