放射性污染条件下土壤微生物活性及群落功能多样性特征  

Characteristics of Soil Microbial Activity and Community Functional Diversity Under Radioactive Contamination

作　　者：王丽超 江世杰 黎先发 WANG Lichao;JIANG Shijie;LI Xianfa(College of Life Science and Engineering,Southwest University of Science and Technology,Mianyang 621010,China)

机构地区：[1]西南科技大学生命科学与工程学院

出　　处：《广东农业科学》2019年第9期63-69,共7页Guangdong Agricultural Sciences

基　　金：西南科技大学龙山学术人才科研支持计划项目(17LZXY10);西南科技大学博士基金(18zx7127);四川省科技厅农业领域研发项目(2018SZ0301)

摘　　要：【目的】揭示放射性污染与土壤微生物活性及群落功能多样性的内在联系,同时为放射性污染土壤生物治理与安全评价提供一定参考。【方法】以我国南方某典型铀尾矿库中采集的土壤为研究对象,使用微生物活性测定方法和Biolog-Eco技术对土壤样品中微生物量氮(MBN)、微生物熵(qMB)、基础呼吸(BRC)和代谢熵(qCO2)等微生物活性指标及微生物群落功能多样性进行分析。【结果】不同污染程度土壤微生物活性呈现显著差异,除qMB外,各取样点的MBN、BRC、qCO2都低于对照水平;相关性分析显示U、226Ra与各指标均呈负相关,但未达到显著水平;放射性污染整体上显著降低了土壤微生物群落对碳源的利用能力,主成分分析(PCA)表明这种差异主要体现在碳水化合物上,其次是氨基酸;不同程度的放射性污染土壤中,微生物群落功能多样性也存在显著差异,污染程度较低的土壤中,微生物多样性整体表现较高。【结论】放射性污染土壤中微生物的活性、群落代谢特征都发生了显著的改变,因此可以将其作为环境监测的敏感指标。【Objective】This study aims to reveal the intrinsic relationship between radioactive pollution and soil microbial activity and community functional diversity,and it also provides a certain reference for bio-control and safety evaluation of radioactive contaminated soil.【Method】Soil samples were taken from the surrounding of a uranium tailings repository in South China,and the micobial activity indicators such as MBN,BRC and qCO2 in soil samples and functional diversity of microbial communities were analyzed by microbial activity determination method and Biolog-Eco technology.【Result】The results showed that soil microbial activity was significantly correlated with pollution concentration,except for qMB,the activities of MBN,BRC and qCO2 of each sampling point were lower than those of the control level.Correlation analysis showed that U and 226Ra were negatively correlated with each index,but were not significant.Radioactive contamination significantly reduced the ability of soil microbial communities to utilize carbon sources as a whole.Principal component analysis(PCA)indicated that such differences were mainly reflected in carbohydrates,followed by amino acids.There were also significant differences in the functional diversity of microbial communities in radioactive contaminated soils of different levels.In soils with lower pollution,the overall microbial diversity was higher.【Conclusion】Compared with the control,the microbial activities and community metabolism characteristics of radioactive contaminated soils have changed significantly,therefore,they can be used as sensitive indicators for environmental monitoring.

关 键 词：铀尾矿 放射性污染 土壤微生物活性 微生物群落多样性 

分 类 号：X172[环境科学与工程—环境科学]