高通量测序助力地质封存CO2泄漏情景下土壤细菌群落信息的挖掘

CO_2地质封存过程复杂,存在CO_2泄漏风险,进而会影响土壤生态系统,为研究地质封存CO_2泄漏应对措施,以玉米为研究对象,采用人工控制释放CO_2系统研究了玉米对地质封存CO_2泄漏的响应特征,并应用高通量测序技术分析了玉米土壤细菌群落结构及遗传多样性。结果表明:土壤CO_2浓度为30×104μL·L~(-1)(30 cm埋深处CO_2浓度)时,玉米表现出较好的适应能力,当CO_2泄漏量增加到40×104μL·L~(-1)以上时,玉米叶片等各项生长指标均表现为受胁迫特征;高通量测序结果显示试验共获得4个土壤样本的70 948个OTUs,但仅3.32%为4种泄漏条件下土壤所共有;遗传信息表明土壤细菌多样性和丰富度变化与CO_2泄漏浓度密切相关;变形菌门、拟杆菌门和酸杆菌门等为土壤优势菌群,而酸杆菌门在土壤CO_2浓度达40×104μL·L~(-1)下相对丰度大幅增加,暗示其可用作地质封存CO_2泄漏对土壤生态系统影响的指示菌。可见泄漏的CO_2会影响农作物生长及土壤细菌群落特征,而变化的土壤细菌多样性会影响农田生态系统功能等。

Study on soil bacterial community under sealed CO2 leakage scenarios by high-throughput sequencing technology

The CO2 geological storage technology carries a risk of the sealed CO2 leakage due to the complexity of the storage process, which might affect soil ecosystem. The response of maize to the leakage scenarios of sealed CO2 was studied by an artificial CO2 release system,and the bacterial community and genetic diversity in soils were analyzed by high-throughput sequencing technology. The results showed that:Maize adapted to 30í104μL·L-1 CO2 scenarios;but more than 40í104μL·L-1 CO2 showed a stress on some physiological indexes of maize leaves and so on. There were a total of 70948 OTUs for four soil samples by high-throughput sequencing technology, but only 3.32%of O-TUs were common under different CO2 leakage scenarios. Changes in soil bacterial diversity and richness were related to CO2 leakage levels. Proteobacteria, Bacteroidetes, and Acidobacteria etc. were dominant species in soils. A significant increase in relative abundance of Aci-dobacteria under 40í104μL·L-1 CO2 concentration suggested that it might be an indicator bacteria for the impact of sealed CO2 leakage on soil ecosystem. Overall, CO2 leakage would affect crop growth and soil microbial community, and changes in microbial diversity might affect functions of agro-ecosystem. This study is important for the establishment of geological CO2 sequestration leakage coping technology.