生物质炭结构性质及其对土壤有效养分和腐殖质组成的影响

生物质炭是具有高度热稳定性和较强吸附特性的含碳物质,不同来源生物质炭的结构性质可能存在着很大的差异。为此对2种自制的不同来源生物质炭和1种商业黑炭进行了结构表征,并研究了添加生物质炭对土壤有效养分和腐殖质组成的影响。结果表明,不同来源的生物质炭在结构上有明显区别：秸秆生物质炭的芳构化程度和热稳定性最低,脂族性最强;商业黑炭缩合程度和热稳定性最高,脂族性最弱;松枝生物质炭介于二者之间。向土壤中添加秸秆生物质炭和松枝生物质炭培养45d后,土壤有机碳含量、胡敏酸和富里酸含量、有效养分含量都有不同程度的增加,同时胡敏酸的色调系数ΔlgK降低,对土壤有机碳的长期保存有积极意义。

The Structural Characteristics of Biochar and Its Effects on Soil Available Nutrients and Humus Composition

Biomass-derived charcoal,also named biochar,has the characteristics of high stability against decay and high capability of adsorption,so it can influence the environment through interaction with climate and geology.There is significant difference in structural characteristics of biochar which is obtained from wood and agricultural residues by means of different procedures.As one possible source of the components with high aromatic structure in soil humus,biochar is of great importance in improving soil fertility,and in maintaining the balance of soil ecosystem.The aim of the research is to investigate the structural characteristics of biochar and the effects of it when applied to soil on available nutrients and humus composition.The results showed that there was great difference between chemical structures of biochar which was produced by different biomass.Aliphatic property of maize straw-derived biochar was stronger than that of pine-derived biochar and commercial black carbon;Aromaticity and thermal stability was on the contrary;Properties of pine-derived biochar was just intermediate.Biochar could influence the soil properties,after being added to soil and incubated for 45 days,and the content of soil organic matter,humic acid and fulvic acid were more or less increased to different levels.However,humification degree decreased with the increase of incubated time.The application of biochar could also increase the content of available nutrients,especially the content of phosphorus,alcium and magnesium.The decreased ΔlgK of humic acid had a positive impact on the long-term preservation of soil organic carbon.