摘要：在京郊露地生产条件下，通过6个不同用量沼肥处理田间小区试验，研究了施用沼肥对大白菜产量和品质效应的影响以及该条件下的土壤氮素平衡。当季试验结果表明，大白菜的产量随施氮水平的增加呈线性+平台的变化趋势，当有机肥氮素用量为1055 kg/ha 时，产量达到最高。大白菜收获后，土壤无机氮残留随施氮量的增加呈平台+线性的变化趋势，当有机肥氮素用量超过1019 kg/ha 时，土壤无机氮残留会急剧增加。大白菜-土壤体系的氮素表观损失随施氮量的增加而显著增加。大白菜硝酸盐含量随着施氮量的增加呈现一种直线增加的趋势，但各处理硝酸盐浓度均未超过600 mg/kg，显著低于北京地方规定的白菜硝酸盐食用标准。

Abstract: In order to study the effect of biogas fertilizer on the yield, quality of Chinese cabbage and soil environment a field experiment with 6 treatments were conducted in Beijing area. The results showed that the yield and N uptake of Chinese cabbage had a linear relationship with applied N rate when it lower than 1055 kg N ha-1, as well as the yield don’t increase any more when the N rate higher than 1055 kg N ha-1. while the residue soil Nmin increased with applied N as plateau-linear trends, the Soil Nmin after harvesting increased dramatically when the N rate was more than 1019 kg/ha. The nitrate content of crop increased with higher N rate, but all of them were less than 600 mg/kg.