黄河滩地和稻田土中铁还原菌、不产氧光合细菌分布机制

【目的】探讨沿黄流域土壤中铁还原菌(ferric reducing bacteria, Fe RB)、不产氧光合细菌(anoxygenic phototrophic bacteria, An PB)的分布机制。【方法】以沿黄流域(原阳段)为研究对象，采集黄河滩地和稻田土样，利用16Sr RNA基因高通量测序和实时荧光定量分析技术，结合统计学分析，揭示Fe RB、An PB菌群结构、丰度和主要环境影响因子。【结果】二者中的优势Fe RB在科(属)水平为Hydrogenophilaceae(Thiobacillus)、 Bacillaceae(Bacillus)、 Clostridiaceae、Rhodobactereace(Rhodobacter)、 Geobacteraceae(Geobacter)，优势An PB为Rhodobactereace(Rhodobacter)、 Chloroflexaceae(Chloronema)、 Acetobacteraceae(Roseomonas)。An PB中Rhodobacteraceae与Fe RB中Bacillaceae、 Clostri...

Distribution of ferric reducing bacteria and anoxygenic phototrophic bacteria in the Yellow River beach and paddy soil

Objective] To explore the distribution of ferric reducing bacteria (FeRB) and anoxygenic phototrophic bacteria (AnPB) in the soil along the Yellow River. Methods] Soil samples were collected from the beach and paddy fields at the Yuanyang section of the Yellow River. High-throughput sequencing of 16S rRNA gene and quantitative real-time PCR were combined with statistical analysis to reveal the structure and abundance of FeRB and AnPB and the main environmental factors affecting the bacteria. Results] The dominant FeRB families (genera) were Hydrogenophilaceae (Thiobacillus), Bacillaceae (Bacillus), Clostridiaceae, Rhodobactereace (Rhodobacter) and Geobacteraceae (Geobacter). The dominant AnPB families (genera) were Rhodobactereace (Rhodobacter), Chloroflexaceae (Chloronema) and Acetobacteraceae (Roseomonas). The relative abundance of Rhodobacteraceae (AnPB) was negatively correlated with that of Bacillaceae and Clostridiaceae (FeRB). The relative abundance of Sphingomonadaceae (AnPB) was negatively correlated with that of Hydrogenophilaceae and Clostridiaceae (FeRB). Soil nitrate nitrogen (NO₃^--N) was negatively correlated with the relative abundance of Rhodobacteraceae but positively correlated with that of Geobacteraceae. Ferrous ions (Fe²⁺) explained 13.5% and 41.8% of the community variations of FeRB and AnPB, respectively; pH explained 65.7% and 42.8%, respectively. The number of total bacteria (BAC), Geo(thermo)bacter (GEO) and phototrophic purple bacteria (PPB) in the Yellow River beach was 2.52 (±3.43)×10⁹, 5.21 (±7.58)×10⁷ and 2.9 (±3.70)× 10⁷ copies/g dry soil, respectively, and that in the paddy soil was 3.82 (±1.29)×10¹⁰, 3.05 (±2.44)×10⁸ and 4.31 (±0.90)×10⁸ copies/g dry soil, respectively. Moreover, the PPB in the upmost soil layer (0-1 cm) were significantly more than those in the 1-2 cm and 2-3 cm soil layers. Fe²⁺ explained 81.5% variations in the absolute abundance of BAC, GEO and PPB. Conclusion] The potential community of FeRB and AnPB and the abundance of GEO and PPB varied between different soil types. Overall, Fe²⁺ played a key role in shaping the distribution pattern of FeRB and AnPB.