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中国有机农业评述及有机和常规生产系统中施肥水平对温室甜瓜生长发育和品质形成的影响

上海交通大学

博士后学位论文

中国有机农业评述及有机和常规生产系统中施肥水平对温室甜

瓜生长发育和品质形成的影响

姓名:Philipp Lehne

申请学位级别:博士后

专业:植物学(植物营养)

指导教师:黄丹枫

20070601

arelargecontributionstOtheemissionofgreenhousegases(N02,N20,Nit3,CH4),eutrophicationofwaterandthereleaseoforganicandinorganictoxicantsintotheenvironment雠9】.Higherefficiencyininputuseandinputreductionarethereforekeyissuesinagriculture.Recyclingisnotanewideatoagriculture.Compostedplantresiduesandlivestockdungaleprominentexamplesofon-farmrecyclingandnight-soilisallexampleforrecyclingthatmayexceedthefarmborders.InGermanythemostwidelyusedrecycledresoLtrccsa『esewagesludgefromcommunalwastewatertreatmentandcompostedorganicwastefromcommunalcollection伊ig.1-3).Animalmealashes[tOlandtheextensionofOil.farmbiogasproductionwithco-fermentationoforganicwastesaddnewresourcesforrecyclinginagriculture.

ThekeyproblemthathastobedealtwithiSthecontentofunwantedsubstancesinrecycledorganicresourcesase.g.heavymetals,organicpollutantsortoxicsubstances.Itisthereforeinquestionwhichoftheseoff-farmresourcescanbeusedinagricultureinthefutureandwhichofthemwillbebannedbylegislation.Foron—farmresourcesthecontaminationofrecycledresourcesismainlydeterminedbythecontaminationoftheexternalinputsase.g.animalfodderanddrugsorpesticides.

F培1-3Containecsforpaper,packages,ghss,o姆面cs,garbage,clothesinGemaanyff'Ilcg2000)

Althoughrecyclinginagricultureisagoodideaandhelpstosaveprimaryresources,

dispc删carehastobetakenaboutcontamination勰recycledproductsarehighly

has

b∞n

dramaticgrowthinorganicagricultureinthelast25years.Untiltheearly

1990sthisgrowthWaSmainlydrivenbygrassrootsorganizations,farmersandtraders.Fromthengovernmentalsubsidies

helpedtofurdacrincreaseorganicproduction【2‘l

buttheoverallbenefitfororganicfarmersisnot

veryhigh瞄1.TheGermanorganic

foodmarketwas3.5billionEuroin2004(2t6%ofthetotalGermanfood

market)andgrowsabout5-15%eachyearwhereasmanyothermarketsshmnkin

feint

years.AstheGermangovernmentfoundorganicfarmingtosupporttheagricultural

policy,organic

food

demand

WaS

encouraged

inreoentyearsby

advcrtis啊nent(Fig.

1-51.

Fig,1-4

Increaseof

o舭icfarming

areainGermanyfrom1978

to

2003嘲

F.喙.1-5

Germangovemmentaladver-t/sementfororganicproducts

(2003):”Organic

isfun”

1.2.4.

Advantagesanddisadvantagesoforganicfarming

Thekeyelementsoforganicfarming

afe

croprotation,biologicalnitrogenfixation

andprotectionofthecrop(orlivestock)frompestsanddiseasesby

management

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