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225 kg/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0-90 cm各土层硝态氮含量不断降低,施氮处理0-30 cm和30-60 cm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60-90 cm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300,375 kg/hm2处理60-90,120-150,150-180 cm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0-90,90-180,0-180 cm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195~225 kg/hm2之间。
Field experiment was carried out to investigate effects of different nitrogen application rates on yield,nitrogen use efficiency of spring maize and distribution of soil nitrate nitrogen（NO-3-N） in Northwest Hebei province.The results showed that yield of spring maize increased with the increasement of N application rate,and yield,N use efficiency of spring maize decreased significantly when N application rate was higher than 225 kg/hm2.From before sowing to after harvest of spring maize,NO-3-N content in 0-90 cm soil layers showed the trends of continuously decreasing under zero N treatment,while NO-3-N content in 0-30 cm and 30-60 cm soil layers showed the trends of increasing first,then decreasing rapidly and in the end keeping stable,NO-3-N content in 60-90 cm soil layers showed the trends of increasing at late growth stage under N treatments.After harvest,NO-3-N content in 0-180 cm soil layers decreased in a wave-manner with increasing of soil depth,when N application rates were 300 kg/hm2 and 375 kg/hm2,NO-3-N content in 60-90 cm,120-150 cm and 150-180 cm soil layers was significantly higher than that under other N treatments.With the increase of N application rate,NO-3-N accumulation in 0-90 cm,90-180 cm and 0-180 cm soil layers showed increasing trend,NO-3-N accumulation in soil layers had high leaching risk on condition of high N application rate.Therefore,through fully analyzing effects of N application on yield and N use efficiency,with the consideration of environment risk of soil NO-3-N distribution,the reasonable N application rate of spring maize should be controlled at 195~225 kg/hm2.
出处
《水土保持学报》
CSCD
北大核心
2011年第2期138-143,共6页
Journal of Soil and Water Conservation
基金
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)
关键词
春玉米
施氮量
氮肥利用率
土壤硝态氮
产量
spring maize
nitrogen application rate
nitrogen use efficiency
soil nitrate nitrogen
yield
