高级检索

    施氮对烤烟氮素积累、分配及土壤氮素矿化的影响

    Effects of Nitrogen Application on Nitrogen Accumulation, Distribution and Soil Nitrogen Mineralization

    • 摘要: 在田间试验条件下,通过设置不同的施氮量处理研究了施氮对烤烟氮素累积、分配及棕壤氮素矿化的影响。结果表明,随施氮量增加,烟株氮素累积量增加;不施氮处理的氮素快速累积期在移栽后9—11周,之后烟株氮素累积量降低;而施氮处理烤烟的氮素快速累积期提前至移栽后7—9周,之后烟株氮素累积量继续增加。氮素在不同器官中的分配比例为叶片>茎>根系,随生育进程,中部叶及下部叶的氮素分配比例降低,烟茎氮素分配比例增加,根系氮素分配比例变化较小;施氮推迟了上部叶最大氮素分配比例出现的时间,不施氮、施纯氮82.5 、105.0 kg/hm2处理分别出现在移栽后11周、13周和15周。随施氮量增加,土壤无机氮含量及氮素表观矿化量增加;施氮推迟了土壤无机氮含量高峰值及阶段氮素表观矿化量高峰值的出现时间。在植烟条件下,移栽后5周内各处理的氮素表观矿化量均为正值,6周后均为负值,与施氮量无关。

       

      Abstract: A field experiment was carried out to investigate the effect of nitrogen application rates on flue-cured tobacco nitrogen accumulation, distribution and soil nitrogen mineralization on brown soil. The results indicated that the nitrogen accumulation of organs and whole shoot increased with higher nitrogen rates. Fast nitrogen accumulation stage of N0 treatment occurred from 9 to 11 weeks after transplanting (WAT), but for the treatments of nitrogen application, the fast accumulation stage occurred two weeks earlier, and the nitrogen accumulation amount still increased after the fast nitrogen accumulation stage, while it decreased in the untreated N0. The nitrogen distribution proportion (NDP) of different tobacco organs were in the decreasing order: leaf>stem>root, the NDP of middle leaves and lower leaves reduced, the NDP of stem increased, and the NDP of root changed gently along with the development process. The occurring time of the maximum distribution proportion of upper leaves of N0, treatment N1 and treatment N2 was 11 WAT, 13 WAT and 15 WAT, respectively, which implied that it was delayed by nitrogen application. The soil Nmin and nitrogen apparent mineralization amount improved with the increasing nitrogen application rates, apex value of soil Nmin and nitrogen apparent mineralization amount were delayed by applying nitrogen. The nitrogen apparent mineralization amount of different treatments was above zero from 0 to 5 WAT, and was blow zero after 6 WAT, irrespective of nitrogen application amount.

       

    /

    返回文章
    返回