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263 个结果
  • 简介:ThispaperexamedtheCupressaceaetaxainChina.Itisidentifledthat30speciesand16varietiesin7generainthefamilyareindigenous,andestimatedthatabout25speciesand4varietieshavebeenintroducedintothiscountrysincethebeginningofthiscentury.Itisurgentthatmorefurthurstudiesneedtobecarriedoutinthecountryonthetaxonomyespeciallyofjunipersandcypresses,onthere-classificationofexistingcultivars,andonthedevelopmentofnewcultivarsforfutureneeds.

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  • 简介:Humanactivitiesmakestrongeffectsonsoilformation.AnthropogenicsoilsaremuchmoreintensiveandextensiveinChinafortheirhistoryofagriculturalproductioncanbedatedbacktomorethan7000yearsagoOwingtodifferentphysicalconditionsandlanduses,theanthropogenicsoil-formingprocessesarevariousAnthrosolsareproposed,andthecorrespondingsoilorderissetupinChineseSoilTaxonomy(CST),Mainlybasedon6Anthropogenicdiagnostichorizons,whichareanthraquicepipedon,hydragrichorizon,irragricepipedon,cumulicepipedon,fimicepipedonandagrichorzon,theAnthrosolsOrderissubividedinto2soilsubordersand4soilgroups.MeanwhiletheclassificationofAnthrosolsinCSThasbeenbasicallyacceptedastheclassificationofAnthrosolsinWorldReferenceBaseforSoilResources(WRB).

  • 标签: 土层 人为土 多样性 累积过程 中国 灌溉农业过程
  • 简介:Paulowniaisafast-growingtreespeciesthatismainlyfoundinthecentralpartofChina.ThreemaincultivationareasofPaulowniaaretheYellow-Huai-HaiPlain,southoftheYangtzeRiver,andaridandsemi-aridareasofNorthwesternChina.Thereare9species,4varietiesand4formsusedintheproductioninChina.Studyachievementswereobtainedinthefieldsofspecies/varietyintroduction,selectionandbreeding,afforestationtechniquesaswellasthecontrolofdiseasesandpests.Themainproblemsexistinginthecurrentproductionincludelackofimprovedvarieties,mix-upofdifferentvarietiesandvarietydegenerationduetothelongcourseofasexualreproduction.Theauthorputforwardcountermeasuresfortheproblems.

  • 标签: 泡桐 分布 品种 繁殖 人工造林技术 病虫害防治
  • 简介:Poroidspeciesofwood-inhabitingfungigrowingonspruce(PiceakoraiensisNakaiorPiceayezoensis(Sieb.&Zucc.)Carriere)inNortheastChinawereinvestigatedduring1993-2002,and71specieswererecordedfromthesetreesortheirwood.SkeletocutislilacinaA.David&JeanKellerandSkeletocutispapyraceaA.DavidarenewtoChina.Fomitopsispinicola(Sw.:Fr.)P.Karst.,Onnialeporina(Fr.)H.Jahn,Perenniporiasubacida(Peck)Donk,Phaeolussckweinitzii(Fr.:Fr.)Pat.,Phellinidiumsulphuras...

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  • 简介:Withavastterritory,Chinaisrichinforestresourcesanddiversifiedenvironments.Thechangesinforestresourceshaveadirectbearingonenvironmentalquality.ThepapergivesadetailedaccountofthedynamicchangeinforestresourcesinChina,includingtheoverallprocessofforestevolution,thestatusquoandfeaturesoftheexistingforestresourcesandthedevelopmentanduseofmajorforestresources.Inaddition,itanalysesthecurrentsituationofChina'senvironmentandexploresthemaincontn'butingfactorsbasedontheoverallenvironmentalsituation.InordertoachievesustainablemanagementofforestresourcesandimprovetheenvironmentinChina,theChinesegovernmentattachesgreatimportancetotheprotectionanddevelopmentofforestresourcesaswellasenvironmentaldevelopmentandimprovement.Thepapergivesanoverviewofthethinkingforsustainableforestresourceandenvironmentaldevelopmentinthefutureandcurrentfocusofefforts.

  • 标签: 中国 森林资源 环境质量 森林经营
  • 简介:ThefuelbreakswereestablishedinsouthChinafrom1950s.Withtheactiveworkoflocalcommunitiesandstategovernment,thefuelbreakshavebeenbuiltfor398,000kilometers.Insomeareas,fuelbreaksandfirebreakshaveconstructedanetworkprimarily,suchasintheprovincesofFujian,Guangdong,Guangxi.Thefuelbreakscanpreventforestfireeffectively.Thathasbeenapprovedbyactualexamplesandburningtests.Thefuelbreaksalsobenefittheforestecosystemandenvironment.Thispapermakes...

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  • 简介:本文首先介绍了中国土地荒漠化现状及其成因.提出了中国在防治荒漠化工作中所采取的主要战略措施,其中包括:(1)通过大众传媒加强荒漠化防治的宣传与教育力度;(2)加强法制教育和执法力度,进一步完善各项法律、法规;(3)通过加强先进科学技术推广与人员培训,促进荒漠化防治工作、巩固成效;(4)制定优先政策,加大投资力度,促进荒漠化防治工作的大力发展.最后,本文介绍了中国荒漠化防治的最新进展.

  • 标签: 荒漠化防治 战略措施 中国
  • 简介:ByreferenceoftheevaluativedataofforestbiodiversitychangesinChinafrom1973to1998,thevariationanalysismodelsofthepressureindexofforestbiodiversity,forestecosystemdiversityandforestspeciesdiversity,aswellasthegeneralindexofforestbiodiversityaredevelopedusingStatisticalPackagefortheSocialSciences(SPSS).Furthermoreestablishedistherelevantmodelofmutationofforestdiversitypotentialfunctions.Thispaperpointsoutthatchangesofforestbiodiversity...

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  • 简介:ApplicationofPRRAtotheRuralDevelopmetinChinaTXApplicationofPRRAtotheRuralDevelopmentinChinaByShenYueqinZhouGuomoYuShuquanLiMin...

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  • 简介:Chinaisnotrichinnaturalforestsources.Owingtonaturalandhistoricalfactors,forestfireshavelongbeenfrequentingChina.Forestfirepreventionisthemostimportantofall.Forestfirepreventionandcontrollinghavelongbeenheldasaveryimportantfactorinourecologicalplans.Takingchina'sspecialgeographicallocation,topography,climateandthedistributionofforestsourcesintoconsideration,wehaveeveryreasontobelievethatforestfiresinChinahavetheirownspecialenv...

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  • 简介:统计生态学与分析技术和方法的前进很快发展。这份报纸在后面的方面在中国关于统计生态学做了评论:数据收集,空间并且时间模式分析,种类丰富和种类区域关系,人口动态,种类亲密关系,社区类似和社区簇分析,和社区分类。

  • 标签: STATISTICS ECOLOGY MATHEMATICAL STATISTICS
  • 简介:在分析中国水土资源的状况及水土流失危害的基础上,作者介绍了中国山区流域经营的主要经验与措施体系;应用全国各大流域20个典型,分析了流域经营的效益.为了判别流域经营的可持续性,提出了包括社会经济与生态环境两个方面的可持续流域经营指标体系.

  • 标签: 水土资源 土壤侵蚀 流域经营 可持续发展
  • 简介:“LOCALREGULATIONS”ANDSOCIALFORESTRYINCHINA¥ByHePikunDuringthelongperiodofsocialforestryproductionandVillagersparticipateinthe...

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  • 简介:伍德composites能通常在三部分被分类:把压成薄片的composites,混合composites和渗透的composites。每部分有它的自己的特征和罐头进一步被划分。这篇论文在中国介绍历史和木头composites的开发的国家。关于把胶水压成薄片的木材的研究是稀罕的,工业几乎不来到是。成就的一个伟人在混合composites被获得了,它是很好工业化的。scrimber上的许多研究被做了,中国研究人员正在寻找在中国开发scrimber工业的一个可行方法。中国研究人员也在学习木头塑料composites(世界和平理事会)花了那么多精力,但是它一直不由于高费用是工业化的。

  • 标签: WOOD COMPOSITES RESEARCH ADVANCE China
  • 简介:CHINAAERIALSEEDINGACHIEVEMENTANDDEVELOPMENT¥ByLiNuyunandZhangJingchunCurrently,aerialseedingisoneofthemostthismethodisquick,e...

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  • 简介:在云南,在地形的生物多样性和脆弱的8个主要方面,生态系统,分发人口,相异的侵略,分离,污染和maladministrationwith,引起生物多样性损失的各种各样的威胁因素被描述了。生物多样性和脆弱在这共存的thefacts糊,这被揭示。因此,为有效保存的6majorcountermeasures和省的biodiversitywere的合理利用与象气候、人种、文化的差异那样的richintangible资源在云南根据科学发展概念,自然保护的原则,保存生物学,资源管理和人类植物学和现在的地位建议了,等等。

  • 标签: 云南 生物多样性 特有分布 脆弱性 生态保护