稳定氮肥用量和施用方式对水稻产量和氮肥效率的影响

通过田间小区试验,研究了稳定氮肥用量及施用方式对水稻产量、氮素累积量、氮肥利用效率、经济效益及土壤养分含量的影响。结果表明,与不施稳定氮肥相比,100%稳定氮肥一次施用、100%稳定氮肥分次施用、85%稳定氮肥一次施用和70%稳定氮肥一次施用分别增产53.1%、61.6%、39.7%和36.7%,植株地上部氮素总累积量分别增加64.0%、80.9%、36.0%和32.3%,经济效益分别增加50.4%、59.5%、37.4%和34.5%。与农民习惯等氮施肥相比,稳定氮肥一次施用和分次施用分别增产5.7%和11.6%,植株地上部氮素总累积量分别增加9.9%和21.2%,经济效益分别增加5.8%和12.2%。等氮施用稳定氮肥较农民习惯施肥促进水稻对氮素的吸收累积,提高了产量,分次施用达到显著性差异。稳定氮肥一次施用和分次施用氮肥表观利用率和农学效率高于农民习惯施氮,且分次施用达到显著性差异,生理效率和偏生产力3处理无显著性差异。施用稳定氮肥能够提高土壤碱解氮含量,且随着施用量增加而增大。稳定氮肥施氮量在240 kg N·hm^-2且基肥与分蘖肥6:4分次施用时,能较好地协调水稻高产与稳定氮肥合理利用的统一。

Effects of Stabilized Nitrogen Fertilizer Application Amount and Application Methods on Yield and Nitrogen Efficiency of Rice

A rice field experiment was carried out in Anhui Province in 2014 to investigate the effects of stabilized N fertilizer (SNF) application amount and its application methods on rice yield, nitrogen accumulation, nitrogen use efficiency (NUE) of rice, economic efficiency and soil nutrients. Compared with non-stabilized nitrogen fertilizer, the yield of SNF treatments as 100% one application, 100% split application, 85% one application and 70% N one application increased 53.1%, 61.6%, 39.7% and 36.7% respectively, total N accumulated by aboveground parts increased 64.0%, 80.9%, 36.0% and 32.3%, and economic benefits increased 50.4%, 59.5%, 37.4% and 34.5% respectively. Compared with local farmer fertilizer practice, the yield of SNF treatments as 100% and 100% split application increased 5.7% and 11.6% respectively. Total N absorbed by aboveground parts increased 9.9% and 21.2%, and economic benefits increased 5.8% and 12.2% respectively. At the same N application amount, SNF with 100% promoted rice yield and N accumulation compared with farmer fertilizer practice and the split application had even more significant difference. The nitrogen apparent efficiency and nitrogen agronomic efficiency of SNF with 100% was higher than farmer fertilizer practice and the split application had even more significant difference. The three treatments of nitrogen physiological efficiency and nitrogen partial factor productivity had no significant difference. SNF could increase soil available nitrogen content, which was increased with the increasing application amount. Based on rice yield and NUE, the optimum SNF application amount was 240 kgN·hm^-2 with the ratio of basal fertilizer to tiller fertilizer of 6:4.