摘要
在南京郊区露地生产条件下，研究了不同施肥处理秋季大白菜生长期的土壤N素供应、作物养分吸收利用和肥料N素损失。结果表明，在大白菜整个生育期，耕层土壤供N量为50．7kg／hm^2，占土壤全N量的1．07％。作物收获期地上部分生物量和N素含量随施N量的提高而升高，施用N肥显著增加了大白菜的生物量，提高幅度高达3—4倍。植株吸收N量70％以上来源于肥料N。在水试验条件下，尿素N肥表观利用率为26％-35％，土壤NO3^--N含量随N肥施用量的增加而升高，主要累积在0—40cm土层中。
A field experiment was conducted on Chinese cabbage in Nanjing suburbs to investigate soil nitrogen supply, nutrient uptake by the vegetable and chemical N losses during its growing period. Results showed that the amount of N supplied to the crop by the soil in the 0 - 20 cm layer was 50.7 kg/hm^2, accounting for 1.07% of the total soil N in the layer. Application of N fertilizer significantly increased yield of Chinese cabbage by 3 ~ 4 times. More than 70% of the N taken up by Chinese cabbage was derived from chemical N fertilizer. In the field experiment, the apparent recovery rate of urea was 26% - 35%. Nitrate content in the 0 - 40 cm soil profile increased with N application rate.
出处
《土壤》
CAS
CSCD
北大核心
2006年第6期692-697,共6页
Soils
基金
国家自然科学基金项目(40171048)资助。
关键词
大白菜
土壤供氮量
氮肥利用率
Chinese cabbage, Soil nitrogen supply, Efficiency of N fertilizer
