水稻秸秆和玉米秸秆在好气和厌氧条件下的腐解规律

采用室内模拟培养的方法，研究了水稻秸秆和玉米秸秆在好气和厌氧条件下的腐解规律。结果表明：在0~3 个月的培养时间内，水稻秸秆和玉米秸秆腐解较快，腐解率达55%以上。在好气培养条件下，水稻秸秆和玉米秸秆质量减少50%所需要的时间（t_1/2）分别为59.2 d和52.9 d，而在厌氧培养条件下的t_1/2分别为72.6 d和79.9 d。水稻秸秆和玉米秸秆在好气培养条件下的碳释放速率常数k（0.61耀0.6 月^-1）高于其在厌氧培养条件下的碳释放速率常数k（0.55耀0.57月^-1）。水稻秸秆和玉米秸秆在好气培养条件下的氮释放速率常数k（0.25耀2.36 月^-1）也高于其在厌氧培养条件下的氮释放速率常数k（0.16耀2.32 月^-1）。水稻秸秆和玉米秸秆中纤维素、半纤维素和木质素含量在好气培养条件下的减少速率高于其在厌氧培养条件下的减少速率。综上所述，好气培养条件有利于作物秸秆降解和营养物质的释放。

Decomposition of Rice Straw and Corn Straw Under Aerobic and Anaerobic Conditions

Decomposition dynamics of rice straw and corn straw at aerobic and anaerobic condition were investigated under the simulated condition in the lab. Results showed that two stages, i.e. the rapid decomposition stage from 0 to 3 months, and the slow one between 3 and 12 months, of decomposition dynamics of rice straw and corn straw were found under anaerobic and aerobic incubation condition, and more than 55%of rice straw and corn mass was lost at the initial 3 months incubation period. The half times(t_1/2)of rice straw and corn straw mass lost under aerobic condition were 59.2 d and 52.9 d, which were short than those(72.6 d and 79.9 d)under the anaerobic condition, respectively. Carbon release constants from rice straw and corn straw under aerobic condition were 0.61 and 0.60 per month, which were higher than those (0.55 and 0.57 per month)under anaerobic condition. The nitrogen release from crop straw followed the same rule as the carbon release from straw. The constants of nitrogen released from rice straw and corn straw under aerobic condition were 0.25 and 2.36 per month, which were higher than those(0.16 and 2.32 per month)under anaerobic condition. The losses of cellulose, hemicelluloses and lignin from rice straw and corn straw under aerobic condition were also higher than those under anaerobic condition. In summary, the aerobic environment increases de composition and release of organic and inorganic substances from crop straw.