玉米秸秆腐解规律及土壤微生物功能多样性研究

Study on the Decomposition Characteristics of Maize Straw and Soil Microbial Functional Diversity

试验以玉米长期连作和玉米—小麦轮作土壤为研究对象,采用网袋法设定秸秆覆盖和深埋2个还田处理,间隔不同时间取样,分析秸秆腐解特征及土壤微生物群落功能多样性。结果表明,针对不同土壤来说,玉米—小麦轮作土壤中2种秸秆还田方式下(T1和T2),玉米秸秆腐解速率、养分(N、P和K)释放率均高于玉米长期连作土壤(CT1和CT2);不同秸秆腐解时间下,土壤微生物群落功能多样性各处理表现不同。总的来说,T1和T2处理的微生物群落平均颜色变化率、丰富度指数、优势度指数和均匀度指数均高于CT1和CT2。在玉米长期连作种植区,秸秆深埋比秸秆覆盖能更有效提高玉米秸秆腐解率和改善土壤微生物群落结构的功能多样性。

The soil of continuous-cropping and alternate-cropping were selected and the two treatments of straw-mulching and straw buried were carried out to study the decomposition characteristics of maize straw and soil microbial functional diversity.The results showed that the straw decomposition rate and nutrition releasing were increased with the time of decomposition.To the different soil,the straw decomposition rate and nutrition releasing were higher in the soil of alternate-cropping than those in the soil of continuous-cropping.During the straw decomposition time,the soil microbial functional diversity of different treatment had different changes.The data of cultivation of 144 hwas used for the study.The AWCD,H,D and Eof T1 and T2were higher than those of CT1 and CT2.In the soil of continuous-cropping,the mode of straw-buried had more improved the straw decomposition rate and the soil microbial functional diversity.