浑善达克沙地生物土壤结皮及其下层土壤中好氧不产氧光营养细菌群落结构及多样性

Community structure and diversity of aerobic anoxygenic phototrophic bacteria in soil crusts and subsoil of Hunshandake deserts

摘要:

[目的]揭示浑善达克沙地不同类型生物土壤结皮（Biological soil crusts，BSCs）及其下层土壤好氧不产氧光营养细菌（Aerobic anoxygenic phototrophic bacteria，AAPB）群落结构及多样性。[方法]利用Illumina MiSeq二代高通量测序平台对pufM基因进行测序，使用生物信息学分析方法对序列进行比对分析AAPB的群落结构和多样性。[结果]生物土壤结皮及其下层土壤中，Proteobacteria和Alpha-Proteobacteria是优势门和纲，主要有6个属Bradyrhizobium（9.69%-90.02%）、Brevundimonas（0.83%-16.04%）、Methylobacterium（1.74%-12.56%）、Rhodospirillum（0.91%-32.87%）、Roseiflexus（0.02%-1.79%）和Sphingomonas（0.13%-11.23%）；结皮层样品间及下层土壤样品间AAPB种类相似，但丰度有差异；随结皮的发育，结皮层及其下层土壤中AAPB群落多样性升高。[结论]浑善达克沙地BSCs中AAPB群落结构相对复杂，与水体和一般土壤环境中的组成区别明显；AAPB多样性高，且多样性随发育阶段升高而升高，预示着AAPB在荒漠生态系统稳定中有重要的作用。

Abstract:

[Objective] To discover the community structure and diversity of aerobic anoxygenic phototrophic bacteria (AAPB) in different types of soil crusts (BSCs) and soils under them.[Methods] The pufM gene was sequenced via the Illumina MiSeq second-generation high-throughput sequencing platform, and the community structure and diversity of AAPB were analyzed by bioinformatics analysis.[Results] In the BSCs and soils under them, Proteobacteria and Alpha-Proteobacteria were the main phylum, and the main genus were Bradyrhizobium (9.69% to 90.02%), Brevundimonas (0.83% to 16.04%), Methylobacterium (1.74% to 12.56%), Rhodospirillum (0.91% to 32.87%), Roseiflexus (0.02% to 1.79%) and Sphingomonas (0.13% to 11.23%). Biological soil crusts and soil under them had the similar community structure, but different in the abundance. With the development of BSCs, the species richness and diversity of the crusts and their underlying soils increased.[Conclusion] The community structure of AAPB in BSCs of Hunshandake sandy land is relatively complex, which is significant different from that in water and general soil environment. The diversity of AAPB is high and the diversity increases with the BSCs development, which suggests that AAPB plays an important role in the stability of desert ecosystem.