摘要
在保护地栽培条件下,通过6个施氮水平的田间小区试验,结合土层原位渗滤装置,研究了施用氮肥对白萝卜（Raphanus sativusL.）产量和硝酸盐含量及土壤硝态氮淋溶的影响。结果表明,施氮处理白萝卜产量比不施氮处理仅增加6.04%～10.92%,当尿素氮施用量大于N 100 kg/hm2时,增产幅度开始下降。不同施氮处理白萝卜产量没有显著差异,说明在土壤基础肥力较高的情况下,增施氮肥不能明显提高白萝卜的产量;单施有机肥白萝卜体内硝酸盐含量为196.86 mg/kg,比不施氮处理降低5.08%。在此基础上加施尿素后,硝酸盐含量随氮肥施用量的增加显著升高（p〈0.05）;0—100 cm土壤剖面硝态氮累积量随氮肥施用量的增加而增加,且与氮肥施用量显著正相关（r=0.993,r0.01=0.917）;白萝卜生长期间收集到的土壤淋溶液中硝态氮浓度较高,平均为32.88 mg/L,硝态氮的淋失量为4.42～6.14 kg/hm2,不同施氮量处理之间没有显著差异。
Massive N fertilizer application on vegetable fields has caused international awareness. It is widely accepted that extraordinarily accumulation of nitrate in vegetable does harm to health of human beings and would also raise a lot of nitrate leaching to rivers and groundwater. A lysimeter experiment with undisturbed soil layers was carried out to study the effects of N rates on radish （ Raphanus sativus L） yield, nitrate content and nitrate leaching in a cinnamon soils under the condition of greenhouse in the suburb of Beijing from Oct. 2007 to Mar. 2008. Residual soil NO3^- -N, yields, and content of nitrate in radish were also measured. There were six treatments （N fertilization levels） in the study, namely： no fertilizers （No）; chicken manure 6570 kg/ha （N1）; chicken manure 6570 kg/ha ＋ N 100 kg/ha（N2） ; chicken manure 6570 kg/ha ＋ N 200 kg/ha（N3） ; chicken manure 6570 kg ＋ N 300 kg/ha（N4） ; chicken manure 6570 kg ＋ N 1015 kg/ha （N5）. The N5 is farmers＇ conventional level of using N. The results show that the yields of radish are only increased by 6.04 % - 10.92 % in the fertilized soil comparing to unfertilized soil. Increasing extent of radish yield would decrease when the urea-N rate exceeds 100 kg/ha. The yields of radish in different N rates have not significance difference each other. So we can conclude when N is fertilized on fertile soils, the yield of radish is not increased remarkably. Nitrate content in radish is about 196.86 mg/kg when the organic fertilizer is only applied, and the content is decreased by 5.08 % comparing to the condition of unfertilized N. When dry chicken manure in combination with urea are fertilized on the soil, the content of nitrate significantly is increased with the increase of N rates （ P 〈 0.05）. The residual nitrateN contents in depths of 0 - 100 cm soil profile are increased with the increase of the N rates and significantly correlated with the rates （ r = 0.993, r0.01 = 0.917）. Nitrate-N concentrations in groundwater is high, reaches to 32.88 mg/L averagely. The leached amount of nitrate-N is 4.42-6.14 kg/ha during the growth of radish and there are not any significant differences between the different treatments.
出处
《植物营养与肥料学报》
CAS
CSCD
北大核心
2009年第4期877-883,共7页
Journal of Plant Nutrition and Fertilizers
基金
农田污染综合防控关键技术研究与示范项目(2006BAD17B09)
农田污染过程阻断关键技术研究项目(2006BAD17B03)资助
关键词
白萝卜
硝酸盐
硝态氮
淋溶
radish （Raphanus sativus L）
nitrate
nitrate-N
leaching
