不同施氮水平对冬小麦季化肥氮去向及土壤氮素平衡的影响  

Effects of different N rates on fate of N fertilizer and balance of soil N of winter wheat

作　　者：刘新宇[1,2] 巨晓棠[2] 张丽娟[1] 李鑫 袁丽金[1] 刘楠[1] 

机构地区：[1]河北农业大学资源与环境科学学院,河北保定071000 [2]中国农业大学资源与环境学院,北京100094 [3]辉得昌远东有限公司,北京100098

出　　处：《植物营养与肥料学报》2010年第2期296-303,共8页Journal of Plant Nutrition and Fertilizers

基　　金：国家自然科学基金项目(30571110和40571072);"十一五"国家科技支撑计划"粮食丰产科技工程项目(2006BAD02A08)"资助

摘　　要：采用田间微区15N示踪技术,研究了冬小麦季化肥氮去向及土壤氮素平衡。结果表明,在供试土壤肥力水平和生产条件下,N 150 kg/hm2的施肥量已达到较高产量,再增加氮肥用量小麦产量不再增加。随着施肥量的增加,地上部吸氮量有所增加,氮肥的表观利用率和农学利用率持续下降,而生理利用率则表现为低—高—低的变化趋势。在低施氮条件下,小麦主要吸收土壤氮的比例高于化肥氮;在高施氮条件下,小麦吸收土壤氮的比例下降。冬小麦收获后,仍有26.7%4~0.6%的氮肥残留在0—100 cm土层中,17.4%2~4.8%的氮肥损失。残留在土壤剖面中的氮肥主要分布在表土层。随着施氮量的增加,土壤氮素总平衡由亏缺转为盈余;土壤根区硝态氮也由播前消耗转为在播前的基础上累加,两个小麦品种表现为相同的趋势。The fate of N fertilizer and balance of soil N under winter wheat farming were studied using filed15N micro-plot.The results show that crop yield would not increase when the nitrogen application rate is above N 150 kg/ha.Apparent recovery efficiency and agronomic efficiency of nitrogen fertilizer are constantly decreased with increasing of rate of nitrogen fertilizer,while the trend of physiological efficiency is low-high-low.At lower N rate,more soil N is absorbed by winter wheat than that from fertilizer N,and the ratio of soil N absorption to fertilizer N absorption is decreased under high N application.After the harvest of winter wheat,26.7%-40.6% of fertilizer N is resided in 0-100 cm,and 17.4%-24.8% of fertilizer N is lost.With increasing of nitrogen fertilizer application,the total balance of soil N is from deficiency to surplus,and NO-3-N in the root zone soil is from consuming nitrogen to cumulating nitrogen before seeding.There is similar trend between two wheat varieties.

关 键 词：冬小麦 氮去向 氮素平衡 15N 

分 类 号：S512.11[农业科学—作物学]