Effects of rice-straw returning to the field on the metabolic diversity of soil microbial communities
稻草还田对土壤微生物群落功能多样性的影响

To evaluate the effects of returning rice-straw to the field on the soil microbial community, the soil microbial communities under three proportions of rice-straw returning to the field (T1: 33%; T2: 67%; T3:100%; CK: 0) were measured. Bacterial amount and metabolic diversity (BIOLOG) assays were performed and significant differences were found in bacterial amount among the three treatments. The two indicators were the highest in T2, and lowest in CK. In the BIOLOGassays, average well colour development (AWCD) and the indices of richness and diversity indicated differences of microbial metabolic diversity. The indices were significantly higher in the soils of T2 and T3 than in CK, suggesting that the ability to utilize carbon sources and the functional diversity were greater in these soils than in T1 and CK. Altogether, bacterial amount and metabolic diversity patterns in soil T2 were dominant, and returning rice-straw to the field improves the structure and function of soil microbial community, especially at a 67% proportion.