摘要
土壤水分条件是影响氮肥吸收与损失的重要因素之一，氮肥的溶解、尿素的水解等都需要水的存在。采用15N示踪方法，研究麦田土壤水分条件对化肥氮（15N）的吸收、残留、淋溶和损失的影响。结果表明，土壤供水量在一定范围内（180～360mm），氮素的损失量与施肥量成正比;氮素利用率及在土壤中残留量均与施肥量成反比，其顺序为N75kg／hm2＜150kg／hm2＞225kg／hm2。其中75kg／hm2的处理，氮素利用率变幅为17.5％～30.5％。在黄淮海平原高产地区化肥氮每公顷年施用量高达500公斤的已属常见，大量施用氟素化肥而氮肥利用率不断下降，使得由于土壤硝酸盐的淋溶污染地下水的潜在威胁日益加大。
Concerning with applied nitrogen fertilizer. the uptake as well as loss of nitrogen is mainly related to soil water content. The effects of soil water condition in wheat field on the uptake, leach and loss of nitrogen fertilizer were studied in this paper using 15N tracing technique. The results showed that within certain range of soil water supply. from 180 to 360 mm of available water storage, the loss of nitrogen was in direct proportion to the amount of fertilizer application and the nitrogen use efficiency decreased with the increase of nitrogen application. In other words, the nitrogen use efficiency decreased with the nitrogen application increased in an order of 75, 150. 225 kg/hm2. one interesting result was that the nitrogen use efficiencies ranged from 17. 9% to 30. 5% for different water treatments(W1, W1 and W1) receiving the same application N rate of 75kg/hm2.
出处
《植物营养与肥料学报》
CAS
CSCD
1998年第3期237-241,共5页
Journal of Plant Nutrition and Fertilizers
基金
国家自然科学基金
