烟秆生物质炭对土壤碳氮矿化的影响

Study on the Effects of Tobacco Stem Biochar on Soil Organic Carbon and Nitrogen Mineralization

为优化烟草废弃物的资源化利用,采用室内培养试验,研究了烟秆生物质炭对土壤有机碳、有机氮矿化特征的影响。结果发现,与对照(生物质炭添加质量分数为0.0%)相比,添加烟秆生物质炭后能一定程度促进土壤有机碳的矿化,且1.0%添加量处理的有机碳累积矿化量最高,其次为0.5%及2.0%的添加量处理;与其他处理相比,2.0%添加量处理能显著降低土壤总有机碳的累积矿化率,促进土壤中有机碳的积累;添加烟秆生物质炭对土壤无机氮含量、有机氮的矿化及硝化速率均无显著影响。说明较高量的烟秆生物质炭(2.0%)添加能提高土壤有机碳含量,对于烟田土壤的增碳固氮效应及废弃烟秆的资源化利用方面具有重要指导意义。

The purpose of this study was to provide reference for the resource utilization of tobacco waste. The soils for test were added with different amounts of tobacco stem biochar (mass fraction of 0.0%, 0.5%, 1.0% and 2.0%) and incubated for 84 days to study the effect of tobacco stem biochar on soil organic carbon (SOC) and nitrogen mineralization characteristics. The results indicated that, compared with the control (mass fraction of 0.0% biochar addition), tobacco stem biochar could promote the soil organic carbon mineralization to certain degree. The accumulative mineralization of SOC was the highest in the 1.0 % biochar addition treatment, followed by the 0.5 % biochar treatment and 2.0 % biochar treatment. The 2.0 % biochar treatment could significantly reduce the accumulative mineralization rate of SOC compared with the other treatments, and then promoted the accumulation of SOC. Furthermore, adding tobacco stem biochar in soil had no significant effect on soil nitrogen mineralization rate and nitrification rate. In summary, tobacco stem biochar added to tobacco soil could effectively improve the SOC content at the higher application rate, which would have important implication for the carbon and nitrogen conservation of tobacco soil, and the resource utilization of the waste tobacco stems.