摘要
为全面掌握氮肥施用对紫色丘陵区稻麦轮作模式下水稻季氮素吸收积累及土壤氮素表观平衡的影响机理,本试验采用6水平氮肥(0~300 kg N/hm^2)随机区组试验设计,研究氮肥用量对稻麦轮作模式下水稻产量、氮素吸收积累及土壤氮素表观平衡的影响。结果表明:随着氮肥用量的增加水稻籽粒产量先增加后趋于平稳,可以用二次方程模拟y=-0.032 x^2+23.50 x+6495,R^2=0.998;氮肥用量与水稻氮素吸收量及土壤氮素表观平衡呈线性关系,线性方程分别为:y=0.27x+85.28,R^2=0.990,y=0.730x-85.32,R^2=0.998。施氮量低于112.5 kg/hm2时,水稻产量较低,氮素表观盈余量为-3.23 kg/hm^2,有耗竭土壤的风险;施氮量在112.5~187.5 kg/hm2时水稻产量稳定,氮素吸收量为135.77 kg/hm^2,氮素表观盈余量为51.56 kg/hm^2,水稻产量和氮素表观盈余维持在较为合理水平,土壤氮肥力和产量得以维持,农业生产可持续发展;施氮量在187.5~300 kg/hm^2的时候,水稻产量趋于稳定,而氮素表观盈余增加到133.68 kg/hm^2,氮素表观盈余增加了159.27%。过多的氮肥通过水体、大气或者其他渠道流失,引起环境污染。因此,从保证粮食安全和控制面源污染的角度出发,四川丘陵区稻麦轮作模式下水稻氮肥用量以187.5kg/hm^2最优。
In order to identify the effect of nitrogen fertilizer application on rice nitrogen uptake and soil nitrogen balance in purple hilly region under rice-wheat rotation system, the randomized blocks by 6 levels of nitrogen fertilizer （0 -300 kg N/hm^2 ） in this experiment were de- signed, and the effects of nitrogen fertilizer application rate on the rice yield, rice nitrogen uptake and distribution and soil apparent balance were investigated. The result showed that： the rice yield reached a peak first and then stablized with the increase of the nitrogen fertilizer, and their relationship was simulated to a quadratic equation： y = -0.032x2 ＋ 23.50x ＋ 6495 ,R^2 = 0. 998; The rice nitrogen uptake and nitrogen apparent balance had a linear correlation with nitrogen fertilizer application, their linear equations were respectively ： y = 0.27x ＋ 85.28, R^2 = 0. 990,y = 0. 730x - 85.32,R^2 = 0. 998. When the nitrogen application rate was less than 112.5 kg/hm^2 , rice yield was low, nitrogen apparent surplus quantity was - 3.23 kg/hm^2 , which had risks of exhausted soil ; When the nitrogen fertilizer application rate was 112.5 - 187.5 kg/hm^2 , the nitrogen uptake was 135.77 kg/hm^2 , the nitrogen apparent surplus amount was 51.56 kg/hm^2, the rice yield and nitrogen apparent surplus maintained were reasonable levels, soil nitrogen fertilizer and production was maintained, and the agricultural production was sustainable development; When the nitrogen fertilizer application rate was 187.5 -300 kg/hm^2, the rice yield was tended to be stable, but the nitrogen apparent surplus amount was 133.68 kg/hm^2 , and the nitrogen apparent surplus amount was increased by 159.27 %. Too much nitrogen was lost by water, air or other channel erosion, which caused environmental pollution. So a nitrogen fertilizer application rate of 187.5kg/hm^2 was recommended under rice-wheat rotation system in purple hilly region for food security and non-point source pollution prevention.
出处
《西南农业学报》
CSCD
北大核心
2016年第8期1903-1907,共5页
Southwest China Journal of Agricultural Sciences
基金
国家科技支撑计划(2012BAD05B03-8)
国家公益性行业(农业)科研专项(201003014)
四川省公益性农业专项(2011NZ0094)
四川省公益性农业专项(2013NZ0028)
四川省创新能力提升工程专项(2016GYSH-023)
关键词
水稻
氮素
吸收
氮素表观平衡
Rice
Nitrogen
Uptake
Nitrogen apparent balance
