华北平原施氮对农田土壤溶液中硝态氮含量的影响

EFFECTS OF NITROGENOUS FERTILIZER APPLICATION ON NITRATE-N CONCENTRATION OF SOIL SOLUTION IN NORTH CHINA PLAIN

该文通过采集土壤溶液并测定其硝态氮 (NO-3 N) ,对不同施N处理下 4 0cm～ 2 2 0cm土层的NO-3 N累积特征进行了研究。结果表明 ,太行山前平原褐土农田 80cm和 1 4 0cm～ 1 60cm处土层为NO-3 N高度聚集层 ;随着氮肥施入的增加 ,土壤溶液中NO-3 N浓度显著增加 ;2 0 0kg·hm- 2 的氮肥施入水平 ,2m～ 2 2m土层中土壤溶液中硝态氮浓度变幅不大 ,说明淋失量很少 ,而 4 0 0kg·hm- 2 和 80 0kg·hm- 2 氮肥施入水平下 ,2m～ 2 2m土层中土壤溶液中硝态氮浓度呈持续增长 ,且增加量主要发生在 7月～ 9月份玉米生育期。

By sampling soil solution and analyzing its concentration of nitrate N, the characteristics of accumulated nitrate N in 40～220cm soil layers, under different N treatments, are studied. The results indicate that the soil layers in depth of 80 cm and 140～160cm are the two layers with highly nitrate N accumulated, and the more the nitrogenous fertilizer application, the higher the concentration of nitrate N in soil solution. When the nitrogenous fertilizer applied is 200 kgm -2 , the concentration of nitrate N in soil solution in depth of 2～2 2m layer changes minor throughout the year, which indicates that there is little nitrogen leaching under such level of nitrogen fertilizer application. While given the amount to 400 kgm -2 and 800 kgm -2 , the concentration of nitrate N increases significantly. And the further examination presents that the increasing period takes place from June to September.