关中平原不同降雨年型夏玉米临界氮稀释曲线模拟及验证  

Simulation and validation of critical nitrogen dilution curve for summer maize in Guanzhong Plain during different rainfall years

作　　者：强生才[1] 张富仓[1] 向友珍[1] 张燕[1] 闫世程 邢英英[1] 

机构地区：[1]西北农林科技大学水利与建筑工程学院,旱区农业水土工程教育部重点实验室,中国旱区节水农业研究院,杨凌712100

出　　处：《农业工程学报》2015年第17期168-175,共8页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家“十二五”863计划项目课题(2011AA100504);教育部高等学校创新引智计划项目(B12007)

摘　　要：过量施氮和降雨变率大是陕西关中平原夏玉米种植中常见的2大问题,临界氮稀释曲线模型是诊断作物氮营养状况的有效手段。该研究选取关中平原主栽的6个夏玉米品种,设置了N0（0）、N1（86 kg/hm^2）、N2（172 kg/hm^2）和N3（258 kg/hm^2）共4个施氮水平,在2013年（生育前期正常,后期大旱）和2014年（生育前期大旱,后期偏涝）这2种降雨年型下构建和验证了基于全生育期干物质的夏玉米临界氮稀释曲线。结果表明：2 a条件下临界氮浓度与地上生物量均符合幂指数关系,但模型参数存在部分差异,基于临界氮稀释曲线所建立的氮营养指数可用来诊断夏玉米氮盈亏状态,诊断结果表明氮营养指数均随着施氮量的增加而增加,且年型之间存在差异,最优施氮量介于86-172 kg/hm^2之间。制定不同降雨年型下夏玉米临界氮稀释模型对于指导精确施氮及生育季氮诊断具有重要的意义。Guanzhong plain of Shaanxi Province is one of the main productions of summer maize, and faces 2 problems： 1） Annual and seasonal large rainfall variability can significantly affect dry matter accumulation of summer maize and growth; and 2） Nitrogen fertilizer is excessively applied because the increase of nitrogen rate application does not synchronize with the increase of maize yield, but lead to a series of environmental problems. The existing crop nitrogen diagnostic tool is time-consuming and costly, so exploring simple and practical techniques for scientific nitrogen application is necessary such as nitrogen dilution curve. In this study, we constructed nitrogen dilution curves and validated its feasibility to diagnose nutrient status in Guanzhong plain. Six summer maize varieties and four nitrogen levels N20（0）, N1（86 kg/hm^2）, N2（172 kg/hm） and N3（258 kg/hm^2） were applied to the study. The study was carried out in College of Water Resources and Architectural Engineering, Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education Northwest AF University, Yangling, Shaanxi China（108°24′E, 34°20′N） in 2013 and 2014. These two years were different with normal rainfall at early stage and drought at late stage in 2013 but drought in early stage and flooding in late stage in 2014. Aboveground biomass, nitrogen content and yield of summer maize were determined. Based on dry matter, the critical nitrogen dilution curves for summer maize were developed and validated. Results showed that exponential function with two parameters including critical N concentration for 1 ton dry matter（CC） and changes of critical N concentration（CR） could be used to describe relationships between the nitrogen concentration and the aboveground biomass in 2 years. In 2013, CC values were 21.91 and 22.3 for dry matter larger and lower than 1.5 t/hm^2; in 2014, CC values were 21.91 and 26.5 for dry matter larger and lower than 0.63 t/hm^2, respectivel

关 键 词：降雨 氮肥 诊断 夏玉米 临界氮浓度 氮营养指数 关中平原 

分 类 号：S365[农业科学—作物栽培与耕作技术] S512.1[农业科学—农艺学]