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89 个结果
  • 简介:“RETIREMENTFORESTS”FORLOCALGROUPLEADERS¥//The"retirementforests"setupforlocalgroupleadersbyJinhuvillageinJiangsuprovincehavep...

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  • 简介:LocatedontheDaxing'anlingforestregionofChina'sfrontier,theDaxing'anlingForestryGroupCo.isoneofthe500nationallargesizeenterprisegroupswithatotalmanagementareaof8.225millionha.Thereare10forestrybureausunderitsjurisdiction,93000in-servicestaffandapopulationof358000.Thenetvalueoffixedassetis3.58billionyuan,Accumulativetotaloutputoftimberhasamountedto110millionm3duringthepast38years.ItsprofitsandtaxturnedovertotheStatehast...

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  • 简介:1.CommunityresourcemanagementandbeneficiarygroupInthemanagementofcommunityresources,thevillagersbeartheresponsibilitiesandrolesofmanagingcommunityresources,atthesametime,theygetbenefitsfromthemanagementinvariousways,forinstance,thecollectingofwildnon-woodforestproducts,theacquiringofmanure,theharves

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  • 简介:Heterotic组理论(HGT)在支持混合玉米繁殖大约100年起了一个主要作用。HGT的基本内容和研究,和它在米饭和玉米的应用程序在这份报纸被总结。另外,为在中国繁殖的混合米饭的困难和挑战被分析,并且在由使用HGT繁殖的混合米饭的必要性和紧急被建议。

  • 标签: 杂种优势群 水稻育种 杂交 玉米育种 水平转移
  • 简介:Excessivenitrogen(N)fertilizerapplicationtowinterwheatisacommonproblemontheNorthChinaPlain.TodeterminetheoptimumfertilizerNrateforwinterwheatproductionwhileminimizingNlosses,fieldexperimentswereconductedfortwogrowingseasonsateightsites,inHuiminCounty,ShandongProvince,from2001to2003.TheoptimumNrateformaximumgrainyieldwasinverselyrelatedtotheinitialsoilmineralNcontent(Nmin)inthetop90cmofthesoilprofilebeforesowing.TherewasnoyieldresponsetotheappliedNatthethreesiteswithhighinitialsoilmineralNlevels(average212kgNha-1).TheaverageoptimumNratewas96kgNha-1forthefivesiteswithlowinitialsoilNmin(average155kgNha-1)beforesowing.ResidualnitrateNinthetop90cmofthesoilprofileafterharvestincreasedwithincreasingfertilizerNapplicationrate.TheapparentNlossesduringthewheat-growingseasonalsoincreasedwithincreasingNapplicationrate.TheaverageapparentNlosseswiththeoptimumNrateswerelessthan15kgNha-1,whereasthefarmers'conventionalNapplicationrateresultedinlossesofmorethan100kgNha-1.Therefore,optimizingNuseforwinterwheatconsiderablyreducedNlossestotheenvironmentwithoutcompromisingcropyields.

  • 标签: 土壤化学 土壤矿物 冬小麦
  • 简介:日前,甘肃省农牧厅、财政厅将拿出905万元以奖代补资金对改造合格的88户蛋鸡规模养殖场进行奖励。其中,对1~3万只蛋鸡养殖户每户补贴10万元,对3~6万只蛋鸡养殖户补贴15万元。

  • 标签: 蛋鸡场 甘肃省 规模养殖场 养殖户 财政厅 补贴
  • 简介:Changesofsoilorganicnitrogenformsandsoilnitrogensupplyundercontinuousricecroppingsystemwereinvestigatedinalong-termfertilizationexperimentinJinhua,ZhejiangProvince,China.ThefertilizertreatmentsincludedcombinationofP-K,N-K,N-P,andN-P-Kaswellasthecontrol.Aftersixyearsofcontinuousdouble-ricecropping,totalsoilNandhydrolysableNcontentsremainedstableinplotswithNtreatments,whilethehydrolysableNcontentsweresubstantiallyreducedinthoseplotswithoutNapplication.Comparedtotheunbalancedfertilizationtreatments,PandKincreasedthepercentageofhydrolysableammoniumNinthetotalsoilNwiththebalancedapplicationofN,andalsomaintainedhigherricegrainyieldsandnitrogenuptake.GrainyieldwaspositivelycorrelatedwithtotalNuptake(r=0.875**),hydrolysableN(r=0.608**),hydrolysableammoniumN(r=0.560**)andthehydrolysableunknownN(r=0.417**).TotalNuptakewaspositivelycorrelatedwithhydrolysableN(r=0.608**),hydrolysableammoniumN(r=0.440**)andhydrolysableunknownN(r=0.431**).Soilnutrientdepletionand/orunbalancedfertilizationtoricecropreducedNcontentinsoilmicrobialbiomass,andthereforeincreasedC/Nratio,suggestinganegativeeffectonthetotalmicrobialbiomassinthesoil.

  • 标签: 微生物 土壤生物学 有机氮 水稻
  • 简介:到环境因素的空间的全体的土壤氮(N)同位素作文和时间的规模和他们的关系的模式说明N周期并且N采购原料,并且是到全球变化的陆上的N周期和它的反应的综合指示物。这研究的目的是:我)15N(15N)在Qinghai西藏的高原上在不同生态系统类型和土壤侧面珍视调查土壤N内容和自然许多的模式;ii)珍视在土壤N内容和土壤15N的模式上检验气候的因素和土壤特征的效果;并且iii)介绍越过生态系统和土壤测试在土壤15N价值和土壤C/N比率之间的关系。土壤侧面沿着二横断在51个地点被取样在长度的1875km和200km分开并且在Qinghai西藏的高原上的森林,草地和大草原里分布式。每个地点被取样从0~40厘米和每件样品的土壤深度的每10厘米为土壤N内容和15N价值被分析。我们的结果比的显示在草地的土壤N和15N价值(040厘米)高得多在荒芜的大草原。当沿着土壤侧面的土壤15N价值的变化不要不是土壤15N价值趋于与土壤深度增加的山草地,低地草地,和适度的大草原在大多数生态系统之中是统计上重要的时,土壤N为每个生态系统与土壤深度减少了。在土壤15N价值和吝啬的年度降水之间的寓言的关系显示土壤15N价值与在荒芜的大草原增加降水直到500公里增加了,然后与越过所有另外的生态系统增加降水减少了。而且,在15N价值之间的寓言的关系和吝啬的年度温度在所有单个生态系统类型存在。土壤N和15N价值(040厘米)随土壤淤泥和泥土内容的增加增加了。而且,大约11的C/N比率的阀值把在土壤15N价值和土壤C/N比率之间的寓言的关系划分了成积极(C/N<11)并且否定(C/N>11)分开,它越过所有生态系统和土壤侧面是有效的。为土壤15N价值的土壤C/N比率的大解释力量建议了那C和N集中,被降水和温度�

  • 标签: 土壤剖面 青藏高原 全氮 环境因子 生态系统 年平均温度
  • 简介:PotexperimentswerecarriedouttoestimateN2fixationbyvetch,milkvetch,sicklealfalfaandbroadbeaninpurestandusinga^15N-labelledsoil.Winterwheatwasusedasthenon-fixingcontrol.The15N-labelledsoilusedwaspreparedbygrowingcorn-wheat-cornsuccessivelyonanearlyorganic-matter-freeXiashuloesssupplementedwithadequateamountsof(15NH4)2SO4,P,Kandmicronutrients,thenincorporatingthese15N-labelledplantmaterialsintothesoilaftereachhavest,andallowingtheplantmaterialstobedecomposedaerobicallyfor410dafterincorporationoftheplantmaterialofthethirecrop.The15Nenrichmentofwheatplant-Nvariedslightlywithorgans,withamaximumdifferenceof9.8%,Basedon15NenrichmentofsoilNinferredfromthemeanvalueofthe15Nenrichmentindifferentorgansofwheat79%-91%oftotalNinthetopsand67%-74%oftotalNintherootsoflegumesstudiedwerederivedfromatmosphere.EstimatebyisotopedilutionmethodwasingoodagreementwiththatbytheconventionaldifferencemethodprovidedvaluesobtainedbythelatterwerecorrectedforseedN,andalsowiththatfromthemeasurementofNaccumulatedinthetopsofthelegumes.

  • 标签: 15N标记土壤 豆科植物 固氮作用 温室试验
  • 简介:“肉价不如菜价”,目前行业的困境显而易见,很多人都感到一筹莫展。逃离行业大可不必,但在痛苦坚守的同时如何尽快走出困境却是一个很现实的问题。那么,如何走出困境呢?这是一个仁者见仁、智者见智的问题,我们观察和总结了大家时下的一些做法,大致有以下几种:

  • 标签: 困境方法 走出困境
  • 简介:Elevatedatmosphericnitrogen(N)depositionhasbeendetectedinmanyregionsofChina,butitseffectsonsoilNtransformationintemperateforestecosystemsarenotwellknown.WethereforesimulatedNdepositionwithfourlevelsofNadditionrate(N0,N30,N60,andN120)for6yearsinanold-growthtemperateforestinXiaoxing’anMountainsinNortheasternChina.WemeasuredgrossNtransformationratesinthelaboratoryusing15NtracingtechnologytoexploretheeffectsofNdepositiononsoilgrossNtransformationstakingadvantageofNdepositionsoils.NosignificantdifferencesingrosssoilNtransformationrateswereobservedafter6yearsofNdepositionwithvariouslevelsofNadditionrate.ForallNdepositionsoils,thegrossNH4+immobilizationrateswereconsistentlylowerthanthegrossNmineralizationrates,leadingtonetNmineralization.Nitrate(NO3-)wasprimarilyproducedviaoxidationofNH4+(i.e.,autotrophicnitrification),whereasoxidationoforganicN(i.e.,heterotrophicnitrification)wasnegligible.Differencesbetweenthequantityofammonia-oxidizingbacteriaandammonia-oxidizingarchaeawerenotsignificantforanytreatment,whichlikelyexplainsthelackofasignificanteffectongrossnitrificationrates.GrossnitrificationratesweremuchhigherthanthetotalNO3-consumptionrates,resultinginabuild-upofNO3-,whichhighlightsthehighriskofNlossesviaNO3-leachingorgaseousNemissionsfromsoils.ThisresponseisoppositethatoftypicalN-limitedtemperateforestssufferingfromNdeposition,suggestingthattheinvestigatedold-growthtemperateforestecosystemislikelytoapproachNsaturation.

  • 标签: N deposition GROSS soil N transformation
  • 简介:Fivehumicfractionswereobtainedfromauniformly^15N-labelledsoilbyextractionwith0.1molL^-1Na4P2O7,0.1molL^-1NaOH,andHF/HCl-0.1molL^-1NaOH,consecutively,andanalyzedby^13Cand^15NCPMASNMR(crosspolarizationandmagicanglespinningnuclearmagneticresonace).Comparedwiththoseofnativesoilshumicfractionsstudiedasawholecontainedmorealkyls,methoxylsandO-alkyls,being27%-36%,17%-21%and36%-40%,respectively,butfeweraromaticsandcarboxyls(bein14%-20%and13%-90%,respectively),Amongthosehumicfractions,thehumicacid(HA)andfulvicacid(FA)extractedby0.1molL^-1Na4P2O7containedslightlymorecarboxylsthancorrespondinghumicfractionsextractedby0.1molL^-1NaOH,andtheHAextactedby0.1molL^-1NaOHaftertreatmentwithHF/HClcontainedtheleastaromaticsandcarboxyls.Thedistributionofnitrogenfunctionalgroupsofsoilhumicfractionsstudiedwasquitesimilartoeachotherandalsoquitesimilartothatofhumicfractionfromnativesoils.Morethan75%oftotalNineachfractionwasinamidefrom,with9%-13%presentasaromaticand/oraliphaticaminesandtheremainderasheerocyclicN.

  • 标签: 芳香族化合物 腐殖质 赋存形态 土壤成分
  • 简介:ExperimentswerecarriedoutonavegetablefieldwithPekingcabbage(Brassicapekinensis(Lour.)Rupr.),cabbage(Brassicachinensisvar.OleiferaMakinoandnemoto),greencabbage(BrassicachinensisL.),spinach(SpinaciaoleraceaL.)andrape(BrassicacampestrisL.)tostudytheeffectsofNformsandNratesontheirgrowthandnitrateaccumulation.Theresultsindicatedthatapplicationofammoniumchloride,ammoniumnitrate,sodiumnitrateandureasignificantlyincreasedtheyieldsandnitrateconcentrationsofPekingcabbageandspinach.Althoughnosignificantdifferencewasfoundintheyieldsafterapplicationofthe4Nforms,nitrateNincreasednitrateaccumulationinvegetablesmuchmorethanammoniumN.ThevegetableyieldswerenotincreasedcontinuouslywithNrateincrease,andoversupplyofNreducedtheplantgrowth,leadingtoayielddecline.Thistrendwasalsotruefornitrateconcentrationsinsomevegetablesandatsomesamplingtimes.However,asawhole,thenitrateconcentrationsinvegetableswerepositivelycorrelatedwithNrates.Thus,additionofNfertilizertosoilwasthemajorcauseforincreasesinnitrateconcentrationsinvegetables.Nitrateconcentrationsweremuchhigherinroots,stemsandpetiolesthaninbladesatanyNrate.

  • 标签: 蔬菜生长 硝酸盐 结构 含氮比率 甘蓝
  • 简介:钾(K)在植物影响生理的过程的一个范围并且是控制庄稼生产率和收益质量的一个关键因素。很少信息都不有关切割花植物的功能上的K营养的效果是可得到的。现在的学习被执行调查在K和N营养之间的相互作用,在花数量和毛莨属asiaticusL的质量上。植物与Kfertigation的三个层次被供应(60,120,或180mgKL−;1)不到50mgNL−;1应用,并且在120mgKL−的中间的水平;1,到N应用的三个层次(50,100,或150mgNL−;1)。二最低K治疗和最低N治疗由于更低的发生在花生产为佼佼者倒下茎,在很快扩展花茎的纸巾与局部性的Ca缺乏联系的混乱。有害效果在180mgKL−的供应下面已经以收益质量是明显的;1和50mgNL−;1,并且没在渗透的潜在的、相对的水内容或植物织物的膜稳定性与变化被联系,或与在除在高N申请下面的减少的Ca以外的叶子的矿物质内容的变化。我们的结果建议R的一个低营养的要求。asiaticusL。为K和N,在在K和N的高集中的申请下面的减少的花质量的织物水关系的参与的缺乏,和茎由Ca的减少的可获得性在N和K的高申请下面倒下到花的膨胀织物的正式就职起源。

  • 标签: 作物生产力 钾营养 花毛茛 亚洲 应用程序 切花植物
  • 简介:据《ScientiaHorticulturae》的一篇研究报道(http://dx.doi.org/10.1016/j.scienta.2016.01.023),来自西班牙的MaríaDoloresLoureiro等人研究了砧木对"AlbarínNegro"葡萄性状的影响。"AlbarínNegro"是一种红色稀有葡萄品种(VitisviniferaL.),种植于西班牙阿斯图里亚斯地区,因其品质好,目前种植面积逐渐扩大。

  • 标签: 葡萄品种 砧木 性状 种植面积 西班牙 MAR
  • 简介:氮使用效率(NUE)在中国是很低的,差不多70%应用的氮化肥的损失在high-yielding稻田被报导。以便调查高亲密关系的铵运输或举起的分子的基础进米饭(OryzasativaL.),我们分析了九铵的表示侧面transporters(AMT),OsAMT1的三各个,OsAMT2和OsAMT3,根据外部N地位在象在这些表示模式的变化一样的米饭生长的二个不同N要求阶段(年轻幼苗阶段和tillering阶段)使用即时反向的抄写聚合酶链反应(RT-PCR)。结果建议九OsAMT基因在米饭植物的不同机关被表示,包括成熟的根,新根,茎,旧叶子和新叶子并且表示模式是相应蛋白质的位置在种系发生的树上特定、独立的机关。OsAMT1;1,3;2和3;3在根和射击被表示,首先旧的叶子,OsAMT1;2和1;3主要在根,和OsAMT2;1,2;2,2;3和3;1主要在射击,首先在新叶子,并且相对更在里面茎比另外的基因。在二个不同N要求阶段的表示模式是一样;在有更大的N要求的tillering阶段,然而,OsAMTs抄本层次比在有低N要求的年轻幼苗阶段的那些大。为48h的N饥饿起来调整的OsAMT1;1,1;2,3;1,3;2,3;3并且下面调整的OsAMT1;3mRNA丰富。后面的N饥饿,NH4+和NH4NO3再供给下面调整的OsAMT1;2和3;3并且起来调整的OsAMT1;3,而NO3再供给下面调整的OsAMT1;1和1;2。这些建议OsAMT的器官特定的表示模式能被N要求和外部N地位调整。

  • 标签: 表达模式 水稻植株 氮素营养 硝酸铵 转运体 逆转录聚合酶链反应