外源酶对秸秆堆肥进程的影响及腐熟度模糊评价

为探讨外源酶制剂对秸秆堆肥腐熟进程的影响,通过模拟堆肥试验研究了分别添加纤维素酶、蛋白酶,以及纤维素酶与蛋白酶混合添加情况下堆肥各项指标的动态变化规律,并利用模糊综合评价法对堆肥腐熟度进行了评价.结果表明,纤维素酶与蛋白酶配合使用对堆肥中纤维素的降解及氮素释放都有较强的促进效果,与对照处理相比,纤维素含量降低了14.9%,C/N降低了18.4%,发芽指数提高了6.0%;单施外源纤维素酶主要是促进了纤维素类物质降解速率,显著提高了发芽指数;单施外源蛋白酶则显著促进了含氮物质的分解,铵态氮及硝态氮含量提高;通过对E4/E6、NH+4-N、NO-3-N、C/N、发芽指数等指标进行模糊综合评价,得出纤维素酶与蛋白酶的配合使用对于促进堆肥腐熟效果最佳,其次是纤维素酶堆肥和蛋白酶堆肥,常规堆肥腐熟程度最低.可见,纤维素酶与蛋白酶配合使用对堆肥腐熟有更好的促进效果,可以推测外源纤维素酶和蛋白酶对于促进堆肥腐熟具有协同作用.

Effects of exogenous enzymes on composting of straw and maturity assessment by fuzzy evaluation

In order to investigate the effects of exogenous enzymes on composting of rice straw, the simulated composting experiment was conducted by the application of exogenous cellulase, protease, and mixed exogenous enzymes(cellulase and protease). The related indices during composting were analyzed. In addition, the effects of exogenous enzymes on the composting process were also evaluated by fuzzy comprehensive evaluation. The main results showed that mixed cellulase and protease had significant promoting effects on cellulose degradation and nitrogen release, cellulose content decreased by 14.9%, C/N decreased by 18.4%, and germination index increased by 6% compared with the control test; exogenous cellulase promoted the degradation of cellulose, and germination index increased significantly; exogenous protease promoted the decomposition of nitrogenous substances significantly, and ammonium nitrogen and nitrate nitrogen increased significantly. According to fuzzy comprehensive evaluation through E₄/E₆, NH₄⁺-N, NO₃^--N, C/N and germination index, the optimal treatment was compost with mixed enzymes application, followed by cellulase application, protease application, and no enzyme application. The results suggested that mixed exogenous enzymes(cellulase and protease) application accelerated the compost maturity. The exogenous cellulase and protease may have a synergistic effect on the maturing process of compost.