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  • 简介:Applyingtheeconomicprinciples,thisarticlecarriesouttheassessmentofeconomicperformancesbroughtbyforestryresearchachievementthroughresearchanddiscussionontheassessmentmethodofeconomicperformancesofprovenancepopularizationofPinusmassonianaL.Thearticlealsobringsintheoptionmethodtofullydisplaythevalueofforestresearchachievement.

  • 标签: 松树 种源试验 种质推广 种源选择 经济效益分析
  • 简介:Basedonlongtermandstationaryresearch,thetemporalandspatialpatternsanddynamiclawsofsoilwatercontentinMinqindesertareawerestudied.Someresultsareasfollows:(1)ThechangeofsoilwatercontentindifferentyearsisnotobviouslyinshrubsandduneofNitrariasibiricaandTamarixramosissima,butitwasgreatinshiftingsanddune,themaximumis2.538%;(2)Theseasondynamicscanbedividedintothreestages:accumulating,consumingandstable;(3)Theverticalchangeofsoilwa...

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  • 简介:Inaspectofthescaleofworks,theThreeNorthShelterbeltProgramisuptonowthemostmagnificentprojectofforestryecologicalconstructionintheworld.Attheendof2000,the1st,2nd,and3rdperiodsofconstructioninthe1stphase(1978-2000)hadbeencompleted.Basedonfuzzycomprehensiveevaluationmethod,thepaperisabouttheresearchesonpost-evaluationinthe1stphaseaimsoftheThreeNorthShelterbeltProgram.Theconclusionobtainedisthattheaimsarepartlysuccessful.

  • 标签: 评价体系 模糊评价 防风林 林业建设
  • 简介:Itisgloballyacceptedthatsoilcarbon(C)dynamicsareatthecoreofinterlinkedenvironmentalproblems,deterioratingsoilqualityandchangingclimate.Itsmanagementremainsacomplexenigmaforthescientificcommunityduetoitsintricaterelationshipwithsoilnitrogen(N)availabilityandmoisture-temperatureinteractions.ThisarticlereviewsthemanagementaspectsofsoilCdynamicsinlightofrecentadvances,particularlyinrelationtotheavailabilityofinorganicNpoolsandassociatedmicrobialprocessesunderchangingclimate.Globally,drasticalterationsinsoilCdynamicsunderchanginglanduseandmanagementpracticeshavebeenprimarilyattributedtothevariationinsoilNavailability,resultinginahigherdecompositionrateandaconsiderabledeclineinsoilorganicC(SOC)levelsduetoincreasedsoilCO_2emissions,degradedsoilquality,andincreasedatmosphericCO_2concentrations,leadingtoclimatewarming.PredictedclimatewarmingisproposedtoenhanceSOCdecomposition,whichmayfurtherincreasesoilNavailability,leadingtohighersoilCO_2efflux.However,aliteraturesurveyrevealedthatsoilmayalsoactasapotentialCsink,ifwecouldmanagesoilinorganicNpoolsandlinkmicrobialprocessesproperly.Studiesalsoindicatedthattherelative,ratherthantheabsolute,availabilityofinorganicNpoolsmightbeofkeyimportanceunderchangingclimate,astheseNpoolsarevariablyaffectedbymoisture-temperatureinteractions,andtheyhavevariableimpactsonSOCturnover.Therefore,multi-factorialstudiesarerequiredtounderstandhowtherelativeavailabilityofinorganicNpoolsandassociatedmicrobialprocessesmaydetermineSOCdynamicsforimprovedsoilCmanagement.

  • 标签: 微生物过程 气候变化 土壤碳 无机氮 动力学 氮库