水旱輪作體系中的養(yǎng)分循環(huán)特征.pdf

1、中國農業(yè)大學博士學位論文水旱輪作體系中的養(yǎng)分循環(huán)特征姓名：石孝均申請學位級別：博士專業(yè)：植物營養(yǎng)學指導教師：張福鎖20030601AbstractEffectofcontinuousapplicationofchemicaland／ororganicfertilizeronproductivityandsoilfertilityaswellasnutrient(N，P’K)cyclingandnutrientbalanceinrice—

2、wheatcroppingsystemswasstudiedbyusingfield，pot，lysimeterexperimentsandlaboratoryanalysisThepurposesofthisstudyweretoquantifytheinput／outputofnutrientresourceanditsrelatedchangeincropproductivitysoilfertilityandsystemsust

3、ainabilityinordertoprovidedetailedinfomlationfornutrientresourceuseandmanagement瓢l(fā)emainresultswereasfollows：During10yearsofthericewheatrotation，applicationofNPKchemicalfertilizerorcombinationofNPKchemicalwithorganicferti

4、lizercouldmaintainorevenincreasecropproductivityandsoilfertilityinricewwheatcroppingsystemUnderaboveconditionsthehighsustainableyieldforriceandwheatandhi酶efficiencyofNfertilizercouldbeachievedyearbyyearwhilethecontentofs

5、oilorganicmatterandN，Pwereincreased，andthebalanceofsoilavailableKcouldbemaintainedInbalancedapplicationofN，只andKchemicalfertilizerledtoareductionofcropyieldandtheefficiencyofchemicalfertilizer瞄wellasdepletionofsoilnutrie

6、ntsThericewheatrotationrepeatedtransitionsfromanaerobictoaembiegrowingconditions，whichgreatlyaffectedsoilnutrientremove，transportandaccumulationSoilmineralNcontentswerelowanddidnotshowtendencyofaeettmulationin0100cmsoilp

7、rofilesafter10yearscontinuousapplicationofNfertilizerTheremainingPfertilizersinsoilafterlongtermappliedPfertilizershadbeentransformedintoinorganicphosphorusofCa：一P、CasP、AIP、Fe—PandO坦whichweremostlyavailableforriceandwhea

8、t。WknsoilPgotexb。austedtheOPbecamethemainavailablePforriceandwheatTheaccumulatedPinsoilhadobviousdownwardtransportationThereleaseofsoilslowlyavailableKandsoilKsupplyingcapacityweIeimprovedduringfloodingperiod，tnthericewh

9、eatcroppingsystems，continuousapplicationofNfertilizeraloneresultedinareductionofcropyieldandNuseefficiencyBalancedsupplyofNandPKnutrientcouldincreasebothyieldandNuseefficiencygrainyieldofriceandwheatwereincreasedby8kgand

10、10kgperlkgNappliedfertilizerNrecoveryratewereincreasedby34549％and406％forwheatandriceintenyears，respectivelyNinputfromenviroranentticewheatcroppingsystemamountedto126kg氌m2，whichwasnotneglectableforoptimizednutrientmanagem

11、entTheNremovalbyriceandwheatharvestmadeup30—38％ofnitrogeninputfromNfertilizerappliedtothesoilcropsystemTheratesofnitrogenleft訊thesoilandlostbyvolatilizationandleachingwelx：intherangeof一59Vr364％and38％～76％respectivelyCombi

12、nationsofN，PandKfertilizersorNPKwithorganicmanurecouldgreatlyreducethelossesofnitrogenbyvolatilizationandleaching：thusincreasetheratesofnitrogenabsorbedbycropsandstoredinthesoilsThelossesofnitrogenbyvolatilizationweresig