Abstract: In order to explore the technological way of improving tobacco soil by biomass carbon, this paper studied the effect of interaction between biochar of different pyrolysed temperatures (360℃ and 500℃) and soil textures (loam soil and sandy soil) on dynamic change of nitrate nitrogen content and apparent N loss of soil-tobaco plant system in 0~30 cm soil layer. The results showed that: ① Applying biochar could increase NO-3-N contents in soil. The soil NO-3-N contents in application of biochar treated by low-temperature (360℃) and high-temperature (500℃) increased by 20.58% and 8.97% than that of the control group. Soil NO-3-N retention capacity applied with low-temperature pyrolysed biochar is better than that with high-temperature pyrolysed biochar. ② The effect of low-temperature carbon on soil NO-3-N was mainly occurred in 0～10 cm soil layer. While, that of high-temperature carbon was in 10～20 cm soil layer. Their effects were 38.39% and 7.37% higher than that of the control, respectively, and all reached the significant level. ③ The NO-3-N contents in loam soil and sandy soil were 16.09% and 29.18% higher than that of the control, respectively, indicating the fertilizer retention effect of applying low-temperature biochar in sandy soil was better than that in loam soil. The NO-3-N contents in loam soil and sandy soil with application of high-temperature biochar were 11.03% or 4.97% higher, respectively than that of the control. It indicated the fertilizer retention effect of applying high-temperature biochar in loam soil was better than that in sandy soil. ④ Application of biochar could reduce the apparent N loss of soil-tobacco plant system. The effect of low-temperature biochar was better than that of high-temperature biochar. The apparent N loss of each treatment (chemical fertilizer + low-temperature biochar in loam soil, chemical fertilizer + high-temperature biochar in loam soil, chemical fertilizer + low-temperature biochar in sandy soil, chemical fertilizer + high-temperature biochar in sandy soil) was decreased by 40.27%, 34.10%, 68.72% and 54.05%, respectively than that of the control. Therefore, applying biochar could strengthen soil NO-3-N retention capacity and reduce apparent N loss in soil-tobacco plant system. The effect of low-temperature biochar was more significant than that of high-temperature biochar. This study provided theoretical guidance for rational application of biochar in tobacco-planting soil.

Key words: biochar, pyrolysed temperature, loam soil, sandy soil, nitrate nitrogen, leaching, apparent loss of nitrogen

摘要： 为探讨生物质炭改良植烟土壤的技术途径，在玻璃温室内，用蒸渗仪种植烟草，研究不同炭化温度（360℃、500℃）的生物质炭与土质（壤土和砂土）互作对植烟土壤0～30 cm土层硝态氮含量动态变化及土壤-烟株体系氮素表观损失量的影响。结果表明：①施用生物质炭能增加土壤硝态氮含量，施用低温炭（360℃）和高温炭（500℃）土壤硝态氮含量较对照分别增加20.58%和8.97%，低温炭比高温炭对硝态氮的持留效果更好；②低温炭对土壤硝态氮的持留作用主要发生在0～10 cm土层，而高温炭主要发生在10～20 cm土层，分别比对照高38.39%和7.37%，均达到显著水平；③施加低温炭后壤土和砂土硝态氮含量分别比对照高16.09%和29.18%，可见施加低温炭对砂土保肥效果的提升高于壤土；而施加高温炭后壤土和砂土硝态氮含量分别比对照高11.03%和4.97%，可见施加高温炭对壤土保肥效果的提升高于砂土；④施用生物质炭能减少土壤-烟株体系的氮素表观损失量，低温炭比高温炭效果更好。各处理（壤土施化肥+低温炭、壤土施化肥+高温炭、砂土施化肥+低温炭、砂土施化肥+高温炭）分别较各自常规施肥对照的氮素表观损失量减少40.27%、34.10%、68.72%和54.05%，均与对照差异显著。因此，施用生物质炭能增强土壤对硝态氮持留效果，减少土壤-烟株体系的氮素表观损失量，低温炭比高温炭效果更显著，为生物质炭在植烟土壤中的合理施用提供理论指导。

关键词: 生物质炭, 炭化温度, 壤土, 砂土, 硝态氮, 淋溶, 氮素表观损失量