施氮量对冀西北春玉米氮肥利用率和土壤硝态氮时空分布的影响_王激清

第25卷第2期水土保持学报

Vol.25No.2

施氮量对冀西北春玉米氮肥利用率和土壤硝态氮时空分布的影响

王激清1,刘社平1,韩宝文2

(1.河北北方学院农林科技学院,河北张家口075000;2.河北省农林科学院农业资源环境研究所,河北石家庄050051)

摘要:在田间条件下研究了施氮量对春玉米产量、氮肥利用率和土壤硝态氮时空分布的影响,旨在为冀西北春玉米氮肥优化管理提供理论依据。研究结果表明,春玉米产量随施氮量的增加而提高,当施氮量高于225kg/hm2时,春玉米产量和氮肥利用率显著降低。从春玉米播种前到收获后,不施氮处理0-90cm各土层硝态氮含量不断降低,施氮处理0-30cm和30-60cm土层硝态氮含量呈先上升后迅速下降并保持稳定的趋势,而60-90cm土层硝态氮在春玉米生长后期有增加的趋势;春玉米收获后随着土层深度的增加,硝态氮呈波浪式下降,施氮量300,375kg/hm2处理60-90,120-150,150-180cm土层硝态氮含量显著高于其它处理。随着施氮量的增加,春玉米0-90,90-180,0-180cm土层硝态氮累积量均呈增加趋势,高施氮量土层累积的硝态氮存在着更大的淋溶风险。因此,综合分析氮肥用量对春玉米产量、氮肥利用率的影响,并考虑土壤硝态氮时空分布下的环境风险,合理的施氮量应控制在195~225kg/hm2之间。关键词:春玉米;施氮量;氮肥利用率;土壤硝态氮;产量

中图分类号:S147.22;S158.3 文献标识码:A 文章编号:1009-2242(2011)02-0138-06

EffectsofNitrogenApplicationonNitrogenUseEfficiencyofSpringMaizeandDistributionofSoilNitrateNitrogeninNorthwestHebeiProvince

WANGJ-iqing,LIUShe-ping,HANBao-wen

1

1

2

(1.CollegeofAgricultureandForestry,HebeiNorthUniversity,Zhangjiakou,Hebei075000;2.Instituteof

AgriculturalResourcesandEnvironment,HebeiAcademyofAgricultureandForestrySciences,Shijiazhuang,Hebei050051)

Abstract:Fieldexperimentwascarriedouttoinvestigateeffectsofdifferentnitrogenapplicationratesonyield,nitrogenuseefficiencyofspringmaizeanddistributionofsoilnitratenitrogen(NO3-N)inNorth-westHebeiprovince.TheresultsshowedthatyieldofspringmaizeincreasedwiththeincreasementofNap-plicationrate,andyield,NuseefficiencyofspringmaizedecreasedsignificantlywhenNapplicationratewashigherthan225kg/hm2.Frombeforesowingtoafterharvestofspringmaize,NO-3-Ncontentin0-90cmsoillayersshowedthetrendsofcontinuouslydecreasingunderzeroNtreatment,whileNO-3-Ncontentin0-30cmand30-60cmsoillayersshowedthetrendsofincreasingfirst,thendecreasingrapidlyandintheendkeepingstable,NO-3-Ncontentin60-90cmsoillayersshowedthetrendsofincreasingatlategrowthstageunderNtreatments.Afterharvest,NO-3-Ncontentin0-180cmsoillayersdecreasedinawave-mannerwithincreasingofsoildepth,whenNapplicationrateswere300kg/hmand375kg/hm,NO3-N

contentin60-90cm,120-150cmand150-180cmsoillayerswassignificantlyhigherthanthatunderotherNtreatments.WiththeincreaseofNapplicationrate,NO-3-Naccumulationin0-90cm,90-180cmand0-180cmsoillayersshowedincreasingtrend,NO3-NaccumulationinsoillayershadhighleachingriskonconditionofhighNapplicationrate.Therefore,throughfullyanalyzingeffectsofNapplicationonyieldandNuseefficiency,withtheconsiderationofenvironmentriskofsoilNO-3-Ndistribution,thereasonableNapplicationrateofspringmaizeshouldbecontrolledat195~225kg/hm.

Keywords:springmaize;nitrogenapplicationrate;nitrogenuseefficiency;soilnitratenitrogen;yield

提高粮食单产,保障粮食安全,必须增加物质投入,其中增施化肥,尤其是氮肥为最重要、最有效的增产措施,因此氮肥对粮食作物的稳定增产起了不可替代的作用

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。但是,当粮食产量达到一定水平,过量的氮肥用

收稿日期:2010-12-27

基金项目:国家科技支撑计划项目(2007BAD87B02-02);河北省科技支撑计划项目(09220903D);河北省重点学科建设基金资助项目;张家口

市科技攻关计划项目(0811038C-3)

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