As the second largest carbon pool, soil has a high CO₂ content, and it has an important impact on water–rock interactions and the bacterial community structure and diversity in soils. In this paper, three sets of laboratory simulation experiments under six levels of partial pressure CO₂ (pCO₂) conditions were used to analyze and study the CO₂–water–rock interactions and the bacterial community structure and diversity changes in soil under normal temperature and pressure. Results (1) The change of pCO₂ had an obvious influence on the chemical components. The dissolution of CO₂ led to the dissolution of dolomite and calcite, which increased the concentrations of HCO₃⁻, Ca²⁺, and Mg²⁺ significantly. (2) The influence of pCO₂ on the bacterial community structure and diversity was different, and the bacterial community structure became more complex and diverse with the extension of the experiment time. In the experiments, Proteobacteria and Firmicutes were the main dominant phyla, and Gammaproteobacteria and Bacilli were the main dominant classes. The abundance of Bacteroidetes and Bacteroidia was significantly increased with the increasing pCO₂. (3) pH had a significant influence on the bacterial community structure during the experiments, and the influences of different chemical components, such as HCO₃⁻, Ca²⁺, Mg²⁺, total dissolved solids (TDS), and K⁺, on the abundance of different bacterial species were significantly different. This work can provide a theoretical basis for the technology of bacterial–geological storage of CO₂, and it has important significance for the protection of the groundwater environment and the soil ecosystem.

作为第二大碳库，土壤中的CO ₂含量高，它对水-岩相互作用以及土壤中细菌群落结构和多样性具有重要影响。本文采用六组分压CO ₂（pCO ₂）条件下的三组实验室模拟实验，来分析和研究常温下土壤中CO _2-水-岩之间的相互作用以及土壤中细菌群落结构和多样性的变化。和压力。结果（1）pCO ₂的变化对化学成分有明显影响。CO ₂的溶解导致白云石和方解石的溶解，增加了HCO浓度₃ ^- ，钙²⁺和Mg ²⁺显著。（2）pCO ₂对细菌群落结构和多样性的影响不同，随着实验时间的延长，细菌群落结构变得更加复杂多样。在实验中，Proteobacteria和Firmicutes是主要优势种，而Gammaproteobacteria和Bacilli是主要优势种。随着pCO ₂的增加，拟杆菌和细菌的丰度显着增加。。（3）pH值对细菌群落结构的显著影响在实验期间，和不同的化学组分，如HCO的影响₃ ^- ，钙²⁺，镁²⁺，总溶解固体（TDS），和K ⁺，对不同细菌种类的丰度有显着差异。这项工作可以为CO ₂的细菌地质储藏技术提供理论依据，对于保护地下水环境和土壤生态系统具有重要意义。