Abstract

This study investigated the effect of corn straw biochar on the decomposition, nutrient transformation, and bacterial community characteristics in the corn straw decomposition process. A 90-day microcosm incubation experiment was performed to assess the effects of corn straw biochar (500 °C, 1 h) on the corn straw decomposition process and the resulting product. Four biochar amendment rates (0%, 5, 10, and 15%, as mass fractions of biochar) and three different addition times (1st day, 30th day, and 60th day) were set in total. The results showed that corn straw biochar significantly increased the pH of the corn straw decomposition process by 0.71–0.73 and increased the electrical conductivity value by 0.64–1.07 μS/cm over that of the controls. In addition, biochar was shown to increase the temperature rise rate and temperature peak of the straw maturation system, and advance the process of straw maturation by 10 days. Thus, treatment with corn straw biochar could accelerate the corn straw decomposition process and change the conditions for microorganisms involved in the process. Furthermore, biochar additions significantly decreased the organic matter content by 9.67% under B3 and T₁ treatment, and enhanced the N, P₂O₅, and K₂O contents of the straw decomposition product by 0.36, 0.19, and 0.88% under B3 and T₁ treatment. Biochar additions could increase the abundance of several effective bacteria closely related to the N, P₂O₅, and K₂O contents of the straw maturation product. The growth of these bacteria was likely to be affected by the increase in pH with biochar addition, which enabled the improvement of the nutrient mineralization process.

摘要

本研究调查了玉米秸秆生物炭对玉米秸秆分解过程中分解、养分转化和细菌群落特征的影响。进行了 90 天的微观孵化实验，以评估玉米秸秆生物炭（500°C，1 小时）对玉米秸秆分解过程和所得产品的影响。总共设置了四种生物炭添加率（0%、5、10 和 15%，作为生物炭的质量分数）和三种不同的添加时间（第 1 天、第 30 天和第 60 天）。结果表明，与对照相比，玉米秸秆生物炭使玉米秸秆分解过程的 pH 值显着提高了 0.71-0.73，电导率值提高了 0.64-1.07 μS/cm。此外，biochar 被证明可以增加秸秆成熟系统的升温速率和温度峰值，并将秸秆成熟过程提前 10 天。因此，用玉米秸秆生物炭处理可以加速玉米秸秆分解过程并改变参与该过程的微生物的条件。此外，在 B3 和 T 下，生物炭的添加显着降低了 9.67% 的有机质含量₁处理，B3和T ₁处理下秸秆分解产物的N、P ₂ O ₅、K ₂ O含量分别提高0.36%、0.19%和0.88% 。添加生物炭可以增加与秸秆成熟产物的 N、P ₂ O ₅和 K ₂ O 含量密切相关的几种有效细菌的丰度。这些细菌的生长很可能受到添加生物炭时 pH 值升高的影响，这有助于改善营养矿化过程。