人工回灌过程中地下水微生物群落变化

人工回灌过程中,回灌水的注入使目的含水层地下水环境发生变化,微生物条件也会随之改变,从而影响地下水环境质量及水文地球化学作用。以上海市某人工回灌试验场为例,在分析人工回灌过程中水化学演化特点的基础上,应用DGGE技术对场地回灌过程中地下水中的微生物群落结构变化进行研究,为评价人工回灌对地下水水质安全的影响提供科学的理论依据。结果表明:人工回灌作用使目的含水层地下水中的Eh值及DO质量浓度升高,分别由64.0 mV、1.12 mg/L升至534.4 mV、1.44 mg/L;同一位置处微生物群落结构与原始地下水状态的相似性随时间降低;同一时刻距离回灌井越远的监测井的微生物群落结构越接近于原始地下水状态。随着回灌的进行,目的含水层地下水中优势菌属(种)共有7种,其中Rubrivivax gelatinosus和Candidatus Accumulibacter phosphatis clade IIA str.的反硝化能力以及Rhodoferax ferrireducens对Fe³⁺的还原能力,对地下水水化学组分产生影响。

Change of the Groundwater Microbial Community During Artificial Recharge Process

The injection of the recharge water changes the groundwater environment and the microenvironment of the objective aquifer,and influences the groundwater environment quality and the hydrogeochemical process during the artificial recharging process.We used the denaturing gradient gel electrophoresis (DGGE)technology to study the change of the groundwater microbial community based on the analysis of the hydrochemistry characteristic and provideda scientific basis for evaluating the effect of groundwater quality by the artificial recharge.The results show that the artificial recharge makes the Eh and DO value of the objective aquifer groundwater increase from 64.0 mV and 1.12 mg/L to 534.4 mV and 1.44 mg/L,the microbial community similarity between the groundwater of the monitoring well and the original groundwater decreases over time but increases with distance. Seven types of microorganisms are identified in the groundwater samples of the objective aquifer,the denitrification of Rubrivivax gelatinosus and Candidatus Accumulibacter phosphatisclade I IA str .and the Fe (III ) reduction of Rhodoferax ferrireducens influence the chemical composition of the groundwater.