摘要
采用室内土柱模拟试验方法 ,研究了不同灌溉施肥方式下尿素态氮在土壤中的迁移、淋溶和转化特征。结果表明 ,灌水量及水肥供应方式是决定尿素态氮在土壤中迁移、转化和淋失的关键因素。氮素淋溶量随灌水量的增加而增加 ;与浇灌施肥相比 ,滴灌施肥显著地降低了氮素的淋溶损失。在淋失的氮素形态中 ,以尿素态氮为主 ,其次为硝态氮 ,铵态氮的淋失量最低。灌水量低时 ,滴灌施肥铵态氮在土壤上层明显累积 ;灌水量增加后 ,这种累积作用减弱。灌水量低时 ,灌溉施肥的土壤硝态氮变化呈上低下高 ,增加灌水量降低了土壤中硝态氮含量 ;滴灌施肥显著地减少了尿素态氮的淋溶损失 ,增加了土壤中有效态氮的含量。
Soil column method was used to study the characteristics of the movement, transformation, and leach of urea-N in soil added by different ways of the fertigation. The result shows that the amount water added and the way of supplying water and fertilizer were two key factors to affect the movement, transformation, and leach of urea-N in soil. The amount of nitrogen leached was increased with the increasing amount of water applied. And compared to the treatment of fertilizer added as flooding irrigation (FIF), the treatment of fertilizer added in drip irrigation (DIF) significantly decreased the nitrogen leached. The main form of N leached was urea-N, next was NO- 3-N; the proportion of NH+ 4-N leached was very low. The NH+ 4-N accumulated in the upper layer of soil when the irrigation water was low; and at the high irrigation rate, this accumulation was decreased. With the low irrigation water, the content of NO- 3-N was lower in the upper layer of soil, and higher in deeper layers. As the increase of water added, the level of NO- 3-N in soil was decreased. It is concluded that, in comparison with FIF, DIF significantly decreased the leaching loss of urea-N from soil, and increased the available N in soil.
出处
《植物营养与肥料学报》
CAS
CSCD
北大核心
2003年第3期271-275,共5页
Journal of Plant Nutrition and Fertilizers
基金
国家自然科学基金项目重大项目 ( 4 9890 3 3 0 )
重点项目 ( 3 0 2 3 0 2 3 0 )
教育部留学回国人员科研启动基金 ( 2 0 0 2 )资助
