控释肥料与普通氮肥混施对春白菜产量、品质和氮素损失的影响

在京郊露地生产条件下，研究了控释肥料与速效化肥混配施用对春白菜产量、品质、氨挥发、土壤硝态氮累积和淋失的影响.结果表明：与习惯施肥处理（施N 300 kg·hm^-2）相比，控释肥料与普通化肥按纯氮比2∶1混配施用（共施N 150 kg·hm^-2）没有造成白菜减产，并显著降低了菜叶中硝酸盐和有机酸含量；与半量施肥处理(施N 150 kg·hm^-2)相比，控释肥与化肥混施处理产量和叶片硝酸盐含量无显著差异.控释肥与化肥混施处理提高了白菜氮肥利用率，减少了N₃-N淋失量和氨挥发总量.白菜收获后，控释肥与化肥混施处理在20～40、60～80、80～100 cm土层的NO₃^--N含量显著低于习惯施肥处理.

Effects of applying controlled-release fertilizer blended with conventional nitrogen fertilizer on Chinese cabbage yield and quality as well as nitrogen losses

An open field experiment was conducted to study the effects of applying controlled-release fertilizer blended with rapidly available chemical N fertilizer on Chinese cabbage yield and quality as well as nitrogen losses, includingammonia volatilization and NO₃^--N accumulation and leaching in Beijing suburb. The results showed that a combined application of 2：1 controlled-release fertilizer and urea fertilizer (total N rate 150 kg·hm^-2) did not induce the reduction of Chinese cabbage yield, and decreased the leaf nitrate and organic acid contents significantly, compared with conventional urea N application (300 kg·hm^-2), and had no significant difference in the cabbage yield and leaf nitratecontent, compared with applying 150 kg·hm^-2 of urea N. The combined application of 2：1 controlled release fertilizer and urea fertilizer improved the N use efficiency of Chinese cabbage, and reduced the ammonia volatilization and NO₃^--N leaching. At harvest, the NO₃^--N concentrations in 20-40, 60-80 and 80-100 cm soil layers were significantly lower in the combined application treatment than in urea N treatment.