不同温度制备的生物质炭对土壤有机碳矿化及腐殖质组成的影响

Effects of Biochar Amendments Synthesized at Varying Temperatures on Soil Organic Carbon Mineralization and Humus Composition

在150～600℃范围内制备生物质炭,并通过室内培养实验研究了施加不同温度制备的生物质炭对土壤有机碳矿化及腐殖质组成的影响。结果表明,随热解温度升高,生物质炭比表面积加大,芳香化结构加深。土壤中添加不同温度制备的生物质炭培养400d后,土壤有机碳的含量都有不同程度的增加。土壤有机碳的累积矿化量随热解温度升高而降低,且添加高温(≥400℃)制备生物质炭的土壤CO2累积释放量低于未添加生物质炭的土壤处理;添加低温(<400℃)制备生物质炭增加了土壤腐植酸和胡敏酸含量,而添加高温(≥400℃)制备生物质炭的土壤其腐植酸和胡敏酸含量的变化不显著。另外,添加生物质炭后,土壤H/F皆未发生显著变化,而胡敏酸的E4/E6值则在添加200℃和250℃制备的生物质炭时显著高于其他处理,添加500℃和600℃制备的生物质炭时显著低于其他处理。

Biochar（BC）was produced at 150~600 ℃. A laboratory experiment was conducted to study the influences of biochar synthesized at different temperatures on soil organic carbon（SOC）mineralization and the composition of humus（HS）contents. The results showed that the specific surface area and aromaticity of BC increased with elevated pyrolysis temperature. Soil amended with BC thus produced resulted in increased soil organic carbon（SOC）content after 400 days incubation. Cumulative CO2 release of the soil also changed after BC amendments. The value deceased with increased pyrolysis temperature. For the soils with BC synthesized at temperatures above 400 ℃ the value was lower than that of black soil. In addition, increased HS and humic acid（HA）contents were founded in the samples amended BC produced at temperatures below 400 ℃. However, similar trend was absent in samples with BC produced at temperatures above 400 ℃. Little change of H/F was observed. E4/E6 values of HA in samples with BC synthesized at 200 ℃ and 250 ℃ were significantly higher than those in other treatments, and the values with BC at 500 ℃ and 600 ℃ were significantly lower than other treatments.