摘要
以新台糖22号(ROC22)为试材,通过网室盆栽试验方法,在总施氮量(15N标记尿素5g/盆,相当于450kg.hm-2)相同条件下,研究了全部基施(T1)、50%基施+50%在分蘖期追施(T2)和30%基肥+30%在分蘖期追施+40%在伸长期追施(T3)3种施氮方式对甘蔗氮肥效率与氮素去向的影响。结果表明:甘蔗吸收的氮素约18%～29%来源于当季施用的尿素氮,71%～82%来自土壤和种茎氮;氮肥利用率为21.0%～34.52%,残留率为37.61%～44.13%,有21.35%～41.39%的氮素损失。3种施氮方式下,氮肥残留在0～20cm土层较多,在20～40cm残留较少。随氮肥施用时间后移,甘蔗吸收的氮素、来源于肥料氮素的比率、氮肥利用率、氮肥残留率、蔗茎产量及产糖量明显增加,而氮肥损失率显著下降,蔗茎的氮素分配率和蔗糖分积累略呈下降趋势,同时氮素在0～20cm土层的残留呈上升趋势,在20～40cm土层呈下降趋势。从经济效益和环境效益考虑,T3施氮方式的效果较为理想。
A pot experiment in greenhouse was conducted with 15 N-labeled urea 5g/pot （ equal to 450kg-hm ^-2 ） total nitrogen by three kinds of treatments of disposable bottom application nitrogen before sowing （T1） , 50% nitrogen before sowing and 50% nitrogrn during tillering stage（3？2）, and 30% nitrogen before sowing, 30% nitrogen during tillering stage and 40% nitrogen applied during elongation stage （T3） to investigate the use efficiency and fate of fertilizer nitrogen using the sugarcane cultivar ROC22. Results showed that almost 18% - 29% of total N uptake by sugarcane was supplied by fertilizer,and 71% -82% N derived from soil and seed-stem. Nitrogen use efficiency ranged from 21.0% to 34.52% , with ~SN-fertilizer residue of 37.61% - 44. 13% , and 15N-fertilizer loss of 21.35% - 41.39% among three treatments. Under the three levels of nitrogen application, residual was 15 N-fertilizer was mainly distributed in 0 - 20cm top soil. The uptake of nitrogen and the proportion of total N from fertilizer in sugarcane plant, the yield of stalk and sugar after the nitrogen applied, and the use efficiency and residue ratio of ~5 N-fertilizer increased significantly over time, while loss rate of 15 N-fertilizer decreased significantly with a slight decline trend of nitrogen distributtion and sucrose accumulation in stalk. The results also indicated that after the nitrogen applied the amounts 15N-fertilizer residue in 0 - 20 cm top soil showed a rising trend, but dropped in 20 - 40cm soil profile. From the viewpoints of economic benefit and ecological benefit, the nitrogen fertilizer applied of T3 could be optimal treatment.
出处
《核农学报》
CAS
CSCD
北大核心
2013年第2期213-218,共6页
Journal of Nuclear Agricultural Sciences
基金
广西自然科学基金(桂科自0832051)
关键词
甘蔗
土壤
施氮方法
15N标记
氮肥去向
Sugarcane
soil
15^ N-labeled
Nitrogen application types
Fate of fertilizer N
