不同水氮处理对棉田氮素平衡及土壤硝态氮移动的影响  

Effect of Different Irrigation and Fertilization Strategies on Nitrogen Balance and Soil Nitrate Movement of High-Yield Cotton System

作　　者：王平[1] 陈新平[2] 张福锁[2] 田长彦[1] 

机构地区：[1]中国科学院新疆生态与地理研究所绿洲生态与荒漠重点实验室,乌鲁木齐830011 [2]中国农业大学资源与环境学院,北京100094

出　　处：《中国农业科学》2011年第5期946-955,共10页Scientia Agricultura Sinica

基　　金：农业部公益性行业项目(200803030);中国科学院西部之光项目(RCPY200803)

摘　　要：【目的】探讨不同水氮管理策略对高产棉田氮素平衡及氮素移动的影响。【方法】设置田间小区试验,研究了常规灌水+常规施氮、优化灌水+优化施氮、常规灌水+优化施氮、优化灌水+优化施氮、常规灌水+不施氮处理条件下的棉田氮素平衡和土壤硝态氮动态。【结果】在常规水氮管理条件下,收获后表观损失量高达163—294 kg.hm-2,60—200 cm土层中硝态氮含量较播前有大幅增加,增量与表观损失的比值达到0.39—0.69;优化水氮管理条件下表观损失量仅为19—87 kg.hm-2;常规水氮处理不同层次土壤剖面上均呈现出硝态氮的积累,而且随灌水量加大累积峰下移,优化水氮管理土壤剖面硝态氮累积程度较小。【结论】在常规施氮体系中氮素的表观损失率达52%—68%,氮素随水移动到根层以下是重要的损失途径之一;本试验中采用的优化水氮管理方法显著减少了硝态氮的淋移损失。【objective】It is of great importance to study the effect of different water and nitrogen management strategies on the nitrogen balance and nitrate movement in soil profile.【Method】In a field experiment,the nitrogen balance and nitrate movement in soil profile of conventional irrigation ＋ conventional N application,optimized irrigation ＋ conventional N application,conventional irrigation ＋ optimized N application,optimized irrigation ＋ optimized N application were studied.【Result】The result showed that the optimized irrigation and fertilization strategy based on soil nitrate quick testing and soil moister measurement could dramatically reduce N losses from 163-294 kg？hm-2 to 19-87 kg？hm-2.Under conventional treatment,nitrate accumulation were greatly increasing in 60-200 cm soil profile after harvesting,and the ratio of nitrate accumulation amount to apparent N losses within 0.39-0.69.According to the results of nitrate movement process,nitrate accumulation become evident in soil profile of conventional N application,but not evident in optimized one.【Conclusion】Apparent N losses can be 52%-68% in conventional N application system,nitrate leaching out of root layer is one of important loss way.Optimized N application system in this experiment can dramatically reduce nitrate leaching.

关 键 词：棉花 氮素 水分 养分平衡 硝态氮 

分 类 号：S562[农业科学—作物学]