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作 者 ：张丽娟;巨晓棠;高强;张福锁

期 刊 ：植物营养与肥料学报 2004年 10卷 5期 页码：455-461

关键词：15N；土壤深层；硝态氮；玉米；

Keywords:15N, deepsubsoil, nitrate, maize,

摘 要 ：采用将¹⁵N标记的硝态氮注射于土壤剖面110cm处的田间微区试验法,在施氮和不施氮两种条件下研究玉米对深层累积硝态氮的利用程度。结果表明,对于试验土壤在施氮和不施氮的条件下,玉米对注射于土壤剖面110cm处¹⁵N标记的硝态氮的回收率分别为11.9％和6.7％;土壤耕层施用氮肥促进了玉米中下层根系的发育,提高了对深层标记NO₃^--N的回收率;在偏旱气候年份,土壤深层110cm处标记的硝态氮没有发生明显向下迁移,仅以标记区域为中心向上和向下扩散了20cm左右。研究结果还表明,通过植物利用土壤深层累积NO₃^--N,避免硝态氮进一步向浅层地下水迁移具有一定的可行性。

Abstract:Recovery of 15N-labeled nitrate injected into 110cm soil horizon by maize in conditions of with or without N fertilizer application was studied using field micro-plot in a Calcaric Cambisol in North China Plain. The results showed that the recovery of ¹⁵N-labeled nitrate diffusing in 100-120cm after injection was 11.9% with N fertilizer application and 6.7% without N application in top soil layer respectively. N fertilizer applied to top soil layer stimulated growth of maize root in subsoil, thus increase the recovery of N-labeled nitrate injected into 110cm soil horizon at seedling stage. In relative drought experimental growth season, ¹⁵N-labeled nitrate didn‘t move downwards obviously because there was not free flow water passing through the ¹⁵N labeled horizon, it just diffused up or down about 20cm distance from labeled horizon. The results could be concluded that utilization of accumulated nitrate in deep subsoil by plants was acceptable to avoiding this kinds of nitrate leached to shallow ground water.

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