不同施肥方式对植烟土壤有效氮、烟株氮累积量和速率的影响

摘要

在鄂西南植烟土壤上研究了不同施肥方式对土壤有效氮、烟株氮累积量以及氮累积速率的影响.结果显示,在不栽烟情况下,施肥后40d内肥料养分损失完毕,60d后土壤有机氮矿化量高于有效氮损失量,土壤有效氮出现净累积；全生育期覆膜方式下移栽后63d内化肥处理(D)土壤有效氮明显高于有机无机配施处理(G),烟株氮累积和土壤有效氮下降成显著负相关,且G处理相关程度(-0.935)高于D处理(-0.661)；前期覆膜团棵揭膜方式下,移栽后42 d内化肥处理(E)土壤有效氮明显高于有机无机配施处理(F),烟株氮累积量和累积速率F处理均高于E处理；提前施肥起垄方式下,化肥处理(Ⅰ)和有机无机配施处理(H)土壤有效氮变化基本一致且烟株氮累积量和累积速率H处理均高于Ⅰ处理.不论何种施肥方式,移栽后前期化肥处理土壤有效氮含量明显高于有机无机配施处理,而烟株氮累积则相反,证明施用有机肥可以使烟株对氮素吸收累积高峰提前,且提高烟株氮累积量和氮累积速率.提前施肥可明显弱化不同肥料处理之间土壤有效氮的差异.%This study investigated the soil available N, N accumulation and accumulative rate of tobacco plants under different fertilizations. The results showed that the fertilizer nutrients from 0-40 cm soil loss completely in 40 days of fertilization in plots without tobacco. Net accumulation of soil available N occurred because mineralization of soil organic N exceed available N loss after 60 days. Soil available N content was obviously higher in chemical fertilizer treatment (D) than in inorganic/organic fertilizer treatment (G) in 63 days after transplanting under plastic muluching in all stage of tobacco plant growth. There was obviously negative correlation with N accumulation of tobacco plant and decline of soil available N. G treatment correlation (-0.935) was higher than D treatment (-0.661). Soil available N content was obviously higher in chemical fertilizer treatment (E) than in inorganic/organic fertilizer treatment (F) in 42 days after transplanting under removing film at bird nest stage. N accumulation and accumulative rate was higher in F treatment than in E treatment. Inorganic fertilizer treatment (I) was identical inorganic/organic fertilizer treatment (H) in soil available N in all stage of tobacco plant growth under advance fertilize and removing film, H treatment high than I treatment in tobacco plant N accumulation and accumulative rate. Inorganic fertilizer treatment had obviously higher than inorganic/organic fertilizer treatment in soil available N whatever fertilize mothed, and reverse in tobacco plant N accumulation. Therefore, Application of organic fertilization not only increased N accumulation in tobacco plant, but also increased plant N accumulative content and rate.