This experiment was done to study the effects of different nitrogen forms and levels on nitrate residues in cabbage and hydrolysable nitrogen contents of Soil.Different proportion of ammonium nitrogen and nitrate nitrogen fertilizer was designed in this study.The results show that greater proportion of nitrate nitrogen fertilization than ammonium nitrogen have significantly effect on the yield of Chinese cabbage. But soil available nitrogen content decreases quickly at later growth stage.Nitrite residues contents is greater than others treatments.Compare to the rate of 3:1,when ammonium nitrogen and nitrate nitrogen ratio is 1:1,the yield of cabbage decreases,but nitrate residues is significantly lower.In field production, ammonium nitrogen and nitrate nitrogen at a ratio of 1:1 application,is the best model of nitrogen applica-tion for economic efficiency and safety and low residue in Chinese cabbage.%以小白菜为材料，在施氮量一定的条件下，通过设置不同硝态氮与铵态氮配施比例，研究了不同氮素形态与水平配施对小白菜硝酸盐残留量及土壤水解氮含量的影响。结果表明：施肥中硝态氮所占比例大于铵态氮时对小白菜产量有显著的促进作用，但生长后期土壤速效氮含量降低较快，小白菜硝酸盐的残留量较高；当硝态氮与铵态氮配施比例为1∶1时，小白菜产量尽管较3∶1时有所下降，但硝酸盐残留量较低。大田生产中，硝态氮与铵态氮按1∶1比例配合施用，是小白菜经济高效、硝酸盐安全低残留的最佳施氮模式。
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