不同施氮情况下小麦玉米间作土壤硝态氮的动态变化  

DYNAMIC CHANGE OF NO 3^--N IN WHEAT/MAIZE INTER CROPING SOIL UNDER DIFFERENT N APPLICATION LEVELS

作　　者：马忠明[1,2] 孙景玲[3] 杨蕊菊[2] 杨君林[1,2] 

机构地区：[1]农业部张掖绿洲灌区农业生态环境重点野外科学观测试验站,甘肃张掖734000 [2]甘肃省农业科学院,甘肃兰州730070 [3]甘肃农业大学,甘肃兰州730070

出　　处：《核农学报》2010年第5期1056-1061,共6页Journal of Nuclear Agricultural Sciences

基　　金："十一五"国家科技支撑计划课题(2006BAD25B09)

摘　　要：本文主要研究了0、210、420和630kg/hm2(NO、N1、N2和N3)4种不同施氮量对小麦玉米间作土壤硝态氮(NO 3--N)含量动态变化的影响。结果表明,0～200cm土层硝态氮的含量整体表现为N3>N2>N1>N0。各生育时期低氮水平下0～60cm土层,中、高氮水平下的0～80cm土层土壤硝态氮含量变化显著。0～60cm土层土壤硝态氮累积量随作物生育时期的变化呈"双峰"曲线,峰值分别出现在小麦挑旗期和玉米大喇叭口期,而60～200cm土层土壤硝态氮累积量的变化呈"单峰"曲线,峰值出现在玉米大喇叭口期。N0处理硝态氮累积量各生育时期变化差异较小。小麦与玉米共生期内0～200cm土层硝态氮含量表现为玉米带>小麦带,差异最大的时期为小麦灌浆期和玉米大喇叭口期。土壤硝态氮向深层的运移量随施氮量增加而增加,与N0相比,施氮后100～200cm土层硝态氮累积量小麦带增加了10.53～62.53kg/hm2,玉米带增加了17.91～70.39kg/hm2。优化氮肥施用比例,适当降低小麦播前施氮量可减小土壤硝态氮深层淋溶的风险。In this paper dynamic change of soil nitrate nitrogen（NO 3^--N） in wheat/maize intercropping field after application nitrogen of 0,210,420 and 630kg/hm^2（N0,N1,N2 and N3） were studied.The results showed that soil NO 3^--N contents in 0 ～ 200cm depth soil samples were observed as N3 N1 N2 N0.Soil NO 3^--N content at different growth stages changed significantly in 0 ～ 60cm depth soil for 210kg/hm^2 N application,and in 0 ～ 80cm depth soil for 420kg/hm^2 and 630kg/hm^2 N application.Soil NO 3^--N accumulation with crop growing were measured as double-peak curve in 0 ～ 60cm depth soil and the peaks appeared in wheat flag stage and maize big bell stage;while soil NO 3^--N accumulation was a single-peak curve in 60 ～ 200cm depth soil which appeared at maize big bell stage;there was almost no change of soil NO 3^--N accumulation for no nitrogen application control during the growth of crops.Soil NO 3^--N content in maize strip soil was much higher than that in wheat strip soil during symbiotic period of wheat and maize,and the maximum difference was recorded at wheat milking stage and maize big bell stage.The amount of soil NO 3^--N transferring to deeper soil increased with the increasing of fertilizer application levels.Compared to control,soil NO 3^--N content in 100 ～ 200cm depth soil increased 10.53 ～ 62.53kg/hm^2 in wheat trip and 17.91 ～ 70.39kg/hm^2 in maize strip.Optimizing N application ratio and decreasing N application amount before sowing were effective to reduce the risk of soil NO 3^--N leaching to deeper layer soil in Hexi oasis irrigation area of china.

关 键 词：施氮量 硝态氮 动态变化 小麦玉米间作 

分 类 号：S512.1[农业科学—作物学] S513