泥石流滩地引洪淤地改造后种植玉米对土壤细菌群落结构特征的影响.

: [Objective] The present paper aimed to study the effects of soil reconstruction and improvement on soil bacterial community structure of debris flow waste-shoal land, providing a scientific basis for the utilization of debris flow waste-shoal land. [ Method] The soil of debris flow waste-shoal land was improved by replacing with out-soil and silting with flood, and then planted com on it. Based on 16S sequencing of soil bacteria, we analyzed the bacterial community diversity. To study the structural characteristics of soil bacterial community, we used the random forest model to predict the key OTU s. [ Result] ( i) The soil bacteria in the debris flow waste-shoal land were mainly involved by Proteobacteria, Actinobacteria, Bacteroidetes and Acitobacterium. The total relative abundance of the four bacterial species was 75%, a mong which Proteobacteria was the most abundant and the relative abundance was more than 40%. (ii) Com planting after silting with flood ( SY) and com planting after replacing with out-soil and silting with flood ( TY) had significant impact on the soil bacterial community structure of debris flow waste-shoal land. The bacteria of soil OTU abundance decreased by the order of magnitude, and the number of unique OTU s was lower than that of unmodified soil ( SS). ( iii) Compared with SS, SY increased the number of soil bacterial species, and changed the abundance of key species of soil bacteria, and reduced species diversity and uniformity. TY could significantly reduce the number of soil bacterial species, and reconfigured the soil community structure. ( iv) SY had the largest proportion of independent explanations for the total variance ( 34. 38 % ), and the direct effect of silting with flood on soil bacterial community structure was significant. ( v) The structure of soil bacterial community was closely related to 2. 68% of the OTUs. According to the importance, the top 6 OTUs belonged to Proteobacteria ( two different families), Ateobacteria, Verrucomicrobia, Planctomycetes and Candidatus_Saccharibacteria [ Conclusion] The direct effect of silting with flood on soil bacterial community structure in debris flow waste-shoal land is significant. After replacing with out-soil, silting with flood and the planting com is conducive to reconfiguring soil bacterial community structure and maintaining the stability of soil community structure. [ABSTRACT FROM AUTHOR]