冬小麦与夏玉米轮作体系中氮肥效应及氮素平衡研究  

Study on Effect of Nitrogen Fertilizer and Nitrogen Balance in Winter Wheat and Summer Maize Rotation System

作　　者：巨晓棠[1] 刘学军[1] 张福锁[1] 

机构地区：[1]中国农业大学植物营养系,北京100094

出　　处：《中国农业科学》2002年第11期1361-1368,共8页Scientia Agricultura Sinica

基　　金：国家自然科学基金倾斜项目 (3 9870 479) ;北京市自然科学基金重大项目 (6980 0 0 1);中国科学院陆地生态过程开发实验室开放基金资助项目

摘　　要：在华北平原北部研究了不同降水年型、不同水氮管理措施对冬小麦和夏玉米产量和氮素平衡的影响。结果表明 ,在施氮量为 0、12 0、2 4 0和 36 0kg·ha-1的条件下 ,12 0kg·ha-1的施氮水平已经达到较高的产量。不施氮肥在第 2季即显著减产 ,但再增加施氮量对产量的影响不大。通过土壤测试进行分期优化施氮 ,夏玉米 冬小麦 夏玉米 3季作物累计施入氮肥 2 2 5kg·ha-1,比常规施氮 (90 0kg·ha-1)少施 6 75kg·ha-1,但作物产量并没有降低。年际供水变化是作物产量年际变化的主要原因。施氮量、播前Nmin和生育期内的氮素矿化量在氮素输入项中均起着重要作用 ,总输入量随着氮肥施用量的增加而显著增加。在氮素输出项中 ,作物携出量并不随输入量的增加有显著的变化 ,从而导致施氮量很高时氮素盈余量也很高。在高量施氮条件下 (≥ 2 4 0kg·ha-1) ,氮盈余主要以残留Nmin积累在土壤剖面中 ,氮素表观损失量随施氮量增加而显著增加。The effect of different rainfall years and different water and nitrogen management ways on winter wheat and summer maize was studied in northern part of North China Plain. The results showed that the highest yield was achieved when N fertilizer rate was 120 kg·ha -1 every season among the fertilizer rate of 0,120,240,360 kg·ha -1 . The yield decreased significantly when no nitrogen fertilizer was applied in two crops, but yield didn't increase even more N fertilizer was applied. 225 kg·ha -1 nitrogen application rate in three crops according to optimum nitrogen fertilization with strategy of soil testing had a similar yield with 900 kg·ha -1 according to conventional farming practice, which illustrated that yield would not decrease if using low amount of nitrogen fertilizer with strategy of soil testing. The main reason of yield change in years with same crop was different water supplying in years. All of nitrogen fertilizer, Nmin before sowing and mineralization played an important role in nitrogen input and total input significantly increased with nitrogen fertilizer increasing. Crop nitrogen uptake had not much change with nitrogen input increasing, Thus leading high nitrogen surplus with high nitrogen application rate. At high nitrogen application rate(≥240 kg·ha -1 ), the main form of surplus nitrogen was residual Nmin accumulated in soil profile and apparent nitrogen loss significantly increased with nitrogen fertilizer increasing.

关 键 词：轮作 冬小麦 夏玉米 氮肥 氮素平衡 肥效 

分 类 号：S143.1[农业科学—肥料学]