不同施氮量下夏玉米田土壤剖面硝态氮累积及其与土壤氮素平衡的关系  

Accumulation of NO_3^--N in soil profile and its relationship with nitrogen balance in summer maize field with different nitrogen application rates

作　　者：刘瑞[1,2,3] 周建斌[1,2] 崔亚胜 王天泰 

机构地区：[1]西北农林科技大学资源环境学院,陕西杨凌712100 [2]农业部西北植物营养与农业环境重点实验室,陕西杨凌712100 [3]宝鸡市农业技术推广服务中心,陕西宝鸡721001 [4]户县土肥站,陕西户县710300 [5]周至县土肥站,陕西周至710400

出　　处：《西北农林科技大学学报（自然科学版）》2014年第2期193-198,共6页Journal of Northwest A&F University(Natural Science Edition)

基　　金：国家"十二五"科技支撑计划项目(2012BAD15B04);国家自然科学基金项目(40773057);西北农林科技大学创新团队项目

摘　　要：【目的】研究不同施氮量对夏玉米收获后0~200cm土层硝态氮分布、累积及土壤氮素平衡的影响。【方法】2009年在位于陕西关中西部地区的户县、周至2县分别设置了6个田间试验,测定了不同施氮量处理下夏玉米收获后土壤剖面硝态氮的含量,计算了土壤氮素平衡值。【结果】夏玉米收获后,在0~200cm土层,随着土层深度的增加,土壤硝态氮含量呈下降后升高的趋势。随着氮肥用量的提高,夏玉米收获后0~200cm土层土壤硝态氮累积量明显增加,二者呈显著正相关关系。随着施氮量的增加,土壤氮素平衡值逐渐增大,其中,当施氮量为90~150kg/hm2时,土壤氮素基本达到平衡;当施氮量达270~450kg/hm2时,土壤氮素有明显盈余。土壤氮素平衡值与0~200cm土层土壤硝态氮累积量之间呈极显著正相关关系,土壤氮素平衡值每增加100kg/hm2,0~200cm土层土壤硝态氮累积量增加约48kg/hm2。【结论】在夏玉米生长季,土壤氮素平衡决定了土壤剖面中硝酸盐的累积状况。[Objective] The experiment was carried out to study the effects of different nitrogen （N） application rates on the distribution, accumulation of NO3-N in soil profile of 0--200 cm and N balance af- ter harvesting summer maize. [Method] In 2009, six field experiments were carried out in Huxian County and Zhouzhi County in Guanzhong, Shaanxi. After harvesting summer maize with different nitrogen applica- tion rates, the NO3-N in soil profile and the N balance were determined. [Result] The amount of NO3-N accumulated in the soil profile and the N balance in soil increased significantly as the increase of nitrogen fertilizer use. When 90--150 kg/hme nitrogen was used,the soil nitrogen was balanced;while when 270--450 kg/hm2 nitrogen was used,increase of the soil nitrogen content was observed in all experiment sites. There was a positive correlation between the soil N balance and the accumulation of NO/-N in soil profile of 0--200 cm. Increase of N balance by 100 kg/hm2 increased NOa-N accumulation in soil profile by 48 kg/hm2. [Conclusion] The amount of NO;--N in soil profile was mainly determined by the N budget bal- ance in summer maize growing season.

关 键 词：夏玉米 施氮量 土壤硝态氮 氮素表观盈亏 

分 类 号：S513.062[农业科学—作物学]