摘要
在冀北高原张北县的草甸栗钙土上，采用15N质量平衡法和微气象学技术，对春小麦中氮肥的去向，以及氨挥发进行了田间原位观测。试验中的氮肥用量为N4.83kg／亩，1／3作基肥、2／3作追肥。基肥随播种施入，追肥于拔节期撤施，随即灌水。结果表明，小麦回收、土壤残留和损失的肥料氮各占施入氮量的37.8％-48.3％、33．80—40．4％和14．30-25．4％。其中，尿素作基肥与作追肥的处理之间，其氮素的去向无明显的差异，但是，小麦对追施的碳铵的回收率比尿素的低约10％，而损失则高7.5％。作追肥施用的尿素和碳铁的氨挥发分别只占施入氮量的1％和5％。此外，试验结果还表明，小麦吸收的氮素中来自肥料氮的比例不足1／3，而以土壤来源氮为主。
Fate of fertilizer N was investigated by the 15N mass balance method, and ammonia volatilization was measured by the micrometeorological technique after urea or ammonium bicarbonate was applied to spring wheat growing on a meadow chestnut soil at Zhangbei County, Hebei Province.The application rate of N fertilizer was totally 72.5kgN/ha, of which 1/3 was applied as basal dressing with seeding, and the rest 2/3 was applied as top dressing immediately followed by irrigation.Results showed that plant recoveries, N remaining in 0-0.8m soil and total N losses of the applied N were 37.8%-48.3%, 33.8%-40.4% and 14.3% 25.4%, respectively.There was no apparent differenee between the fathe of urea N applied as basel dressing and top dressing.However, whil N fertilizer was applied as top dressing, plant recovery was 10% higher from urea than from ammonium bicarbonate, and in contrast, N loss was 7.5% lower from the former than from the latter. Ammonia volatilization was as low as 1% and 5% of the applied N When urea and ammonium bicarbonate were applied as top dressing, respectively. Results also showed that less than 1/3 of the N taken up by what was derived from the applied N fertilizers, and thus the rest was derived from the soil.
出处
《土壤学报》
CAS
CSCD
北大核心
1997年第1期60-66,共7页
Acta Pedologica Sinica
基金
国家自然科学基金
关键词
小麦
化肥氮去向
氨挥发
春小麦
栗钙土
fate of fertilizer N, ammonia volatiliztion, spring wheat, chestnut soils
