摘要： 为明确施用生物炭对油麦菜生长、氮素利用和淋溶的影响,通过盆栽试验,测定了不同处理条件下砖红壤-油麦菜系统土壤淋溶液不同形态氮淋失量、油麦菜农艺形态指标以及植株吸氮量.结果表明:有机氮淋溶量占砖红壤总氮淋溶量的73.8%~77.5%.常规化肥处理铵态氮、硝态氮、有机氮和总氮淋溶量最高,分别为3.9,48.3,163.2,215.4 mg/盆.椰壳生物炭(1%,2%,5%,m/m)与腐植酸肥配施处理铵态氮、硝态氮、可溶性有机氮和总氮淋失量分别比常规化肥处理降低40.6%~52.4%,28.8%~54.9%,22.7%~55.5%,24.4%~55.4%.添加椰壳生物炭油麦菜生物量、氮素利用率分别比单施腐植酸肥提高9.46%~26.44%,9.86%~13.61%;但是过量施用会影响生物量的积累,抑制根系的生长.椰壳生物炭施用量为3.2%(m/m)时油麦菜生物量最大.

关键词: 砖红壤, 油麦菜, 椰壳生物炭, 氮淋失, 氮素利用率

Abstract: It is very important for non-point pollution control to using appropriate agronomic approaches to reduce nitrogen leaching loss from soil.This experiment was conducted to clarify the impacts of biochar addition on leaf-used lettuce growth,nitrogen utilization and leaching.With pot experiment,leaching amounts of different form nitrogen,agronomic characteristics and nitrogen uptake of leaf-used lettuce were determined under no fertilizer,chemical fertilizer,humic acid fertilizer and application.The results showed that the dissolved organic nitrogen(DON) accounted for 73.8%-77.5% of total N leaching.Among all treatments,the highest amout of N was leached for the conventional treatment,and its ammonium nitrogen(AN),nitrate nitrogen(NN),DON and total nitrogen (TN) leaching were 3.9,48.3,163.2,215.4 mg/pot,respectively.Compared with chemical fertilizer treatment,AN,NN,DON and TN leaching with coconut shell biochar (1%,2%,5%;m/m) were reduced by 40.6%-52.4%,28.8%-54.9%,22.7%-55.5% and 24.4%-55.4%.The biomass of leaf-used lettuce and N use efficiency with biochar application increased 9.46%-26.44% and 9.86%-13.61%,respectively.However,its over-application affected the biomass accumulation of leaf-used lettuce and restrained its root growth.The biomass of leaf-used lettuce was up to the maximum with the 3.2% (m/m) biochar admentment.

Key words: Latosol, Leaf-used lettuce, Coconut shell biochar, N leaching, N use efficiency

中图分类号: 

• S143.1