微生物对scCO2-咸水-砂岩体系中矿物反应的影响

利用Illumina MiSeq对scCO₂-咸水-砂岩体系中微生物16S rRNA基因V3-V4区进行分析，探究高压反应釜体系中微生物对scCO₂的响应及微生物对矿物反应的作用.结果显示，生物量受pH值影响较大，初始pH值为7.02，生物量11.02×10⁶gene/mL，30d时pH值降至5.65，生物量降至0.26×10⁶gene/mL；随着矿物溶蚀，90d时pH值增至5.87，生物量增至4.61×10⁶gene/mL.群落结构中，phylum Proteobacteria（52.60%（30d），55.34%（90d））与phylum Firmicutes（46.89%（30d），43.89%（90d））为优势菌门.在属水平，30，90d时Exiguobacterium，Citrobacter，Acinetobacter与Pseudomonas为优势菌属.产酸菌（Exiguobacterium，Acinetobacter与Pseudomonas）促进了长石与粘土溶蚀，咸水中K⁺，Na⁺，Ca²⁺，Mg²⁺，T-Fe浓度高于空白组；铁还原菌（Citrobacter）提高了Fe（Ⅱ）/Fe（Ⅲ）比值；微生物膜对Ca²⁺、Mg²⁺、Fe²⁺具有吸附作用.SEM结果显示，微生物介导下先于空白组出现菱铁矿沉淀.scCO₂-咸水-砂岩体系中适应菌能促进矿物溶蚀与碳酸盐矿物捕获.

Impact of microorganisms on the mineral interaction in scCO2-saline-sandstone system

Through the Illumina MiSeq analysis within V3-V4region of 16S rRNA gene, the response of microorganisms to scCO₂ and its feedback on the mineral interaction in scCO₂-saline-sandstone system was investigated. The results showed that biomass was affected by pH value. The initial pH was 7.02 and biomass was 11.02×10⁶ gene/mL. And the pH dropped to 5.65 and biomass decreased to 0.26×10⁶ gene/mL at 30^th-day. However with the dissolution of minerals, the pH increased to 5.87 and biomass increased to 4.61×10⁶ gene/mL at 90^th-day. In the community structure, phylum Proteobacteria (52.60% (30d), 55.34% (90d)) and phylum Firmicutes (46.89% (30d), 43.89% (90d)) were dominant phylum. At the genus level, Exiguobacterium, Citrobacter, Acinetobacter and Pseudomonas were dominant genus at 30^th and 90^th-day. Acid-producing bacteria (Exiguobacterium, Acinetobactera and Pseudomonas) promoted the dissolution of feldspar and clay, and the concentrations of K⁺, Na⁺, Ca²⁺, Mg²⁺ and T-Fe were higher than those in blank group. Iron-reducing bacteria (Citrobacter) increased the ratio of Fe(Ⅱ)/Fe(Ⅲ). Biofilm showed an adsorption function of Ca²⁺, Mg²⁺ and Fe²⁺. At last, the SEM results showed that the micron-mediated precipitation of siderite appeared before the blank group. Therefore, the adaptable bacteria in the scCO₂-salt-sandstone system could promote the mineral dissolution and carbonates capture.