CO_2地质封存泄漏对土壤微生物群落的影响  

Effects of CO_2 geological storage leakage on soil microbial community

作　　者：陈浮[1,2] 杨宝丹 马静[1] 侯湖平[2] 张绍良[1] 

机构地区：[1]中国矿业大学低碳能源研究院,江苏徐州221008 [2]中国矿业大学环境与测绘学院,江苏徐州221116

出　　处：《中国矿业大学学报》2016年第6期1285-1293,1299,共10页Journal of China University of Mining & Technology

基　　金：国家科技支撑计划(2012BAC24B05);江苏省煤基CO2捕集与地质储存重点实验室开放基金资助项目(2015A01;2015B02)

摘　　要：土壤微生物对CO_2的耐受性和敏感性有助于监测和评估地质封存泄漏风险.通过构建CO_2泄漏模拟实验平台,采用Miseq平台Illumina二代基因测序技术观测空白对照组和400,800,1 200,2 000g/(m^2·d)等4个梯度持续通气60d后土壤微生物群落的响应,并考察2 000g/(m2·d)通气组停止通气60d后微生物群落的恢复能力.研究后发现不同微生物群落结构与组成在中、低浓度CO_2胁迫下表现为抑制性,但在高和极高浓度下菌群反应差异显著.拟杆菌目相对丰度具有极大的可变性,可作为微生物敏感性指标用来评估CO_2泄漏风险.微生物通过改变自身结构与组成以适应CO_2胁迫,但群落结构受损后恢复困难.研究结果表明:1)CO_2泄漏造成了土壤有机质持续增加,最高上升了29.4%.电导率、pH和硝酸盐则持续下降,硝酸盐浓度最大下降了85.5%;2)Chao1和Shannon指数随着泄漏量持续加大分别增加了18.40%±2.40%和6.20%±1.20%;3)酸杆菌门、放线菌门、拟杆菌门、绿弯菌门、厚壁菌门、变形菌门等6个主要类群在不同CO_2泄漏胁迫下表现各异,其中拟杆菌目占比从38.2%急剧下降至7.90%,其它类群占比则有所上升;4)基于OTU分类的微生物群落β多样性与CO_2泄漏梯度存在显著相关(p<0.01),但是受土壤pH,EC值和硝态氮的影响十分显著(p<0.01);5)2 000g/(m2·d)组在停止通气60d后土壤微生物群落结构几乎没有恢复.The tolerance and sensitivity of soil microorganisms to CO_2 are conducive to monitor and assess leakage risks of the geological storage.By constructing the CO_2 leakage simulation platform and adopting the Illumina second-generation DNA sequencing technique on the Miseq platform,responses of microbial community of the control group（without CO_2leakage）and the experimental group（with CO_2 leakage intensities of 400,800,1 200 and 2 000g/（m^2·d）and continuous ventilation for 60days）were observed.Also,a resilience group（with CO_2 leakage intensity of 2 000g/（m^2·d）,ventilation for 60 days and stop ventilation for another 60days）were designed to investigate the resilience ability of microbial consortium.It is observedthat the structure and composition of microbial communities was inhibited under low and middle concentrations of CO_2 stress,whereas the reaction of bacterial consortium was significantly different under high and extremely high CO_2 concentrations.The relative abundance of Bacteroidales order demonstrated a great variability,which might be used as a microbial sensitivity index to assess the risks of CO_2 leakage.The microorganism could adapt to the CO_2 stress by changing their own structure and composition,but the recovery process was difficult to carry out once the community structure was damaged.Research results showed that as a result of CO_2 leakage,the content of soil organic matter increased continuously and the largest increment is up to 29.4%;by contrast,the values of electrical conductivity,pH and nitrate continued to decline,and the nitrate concentration dropped by 85.5% at maximum.The Chao and Shannon indexes increased by 18.40% ±2.40% and 6.20% ±1.20% respectively as the amount of CO_2 leakage increased.The reactions of six major communities including Acidobacteria,Actinobacteria,Bacteroidetes,Chloroflexi,Firmicutes and Proteobacteria varied under different CO_2 leakage stress,among which the proportion of Bacteroides dropped sharply from38.2%to 7.90%,while the percen

关 键 词：地质封存 Illumina测序 CO2泄漏 微生物群落 多样性分析 

分 类 号：X171[环境科学与工程—环境科学] X172