Vucinic Luka, O'Connell David, Teixeira Rui, Coxon Catherine, Gill Laurence
Department of Civil, Structural and Environmental Engineering University of Dublin Trinity College Dublin Ireland.
Department of Geology and Trinity Centre for the Environment University of Dublin Trinity College Dublin Ireland.
Water Resour Res. 2022 May;58(5):e2021WR029840. doi: 10.1029/2021WR029840. Epub 2022 Apr 27.
Microbial pollution of aquifers is a persistent water quality problem globally which poses significant risks to public health. Karst aquifer systems are exceptionally vulnerable to pollution from fecal contamination sources as a result of rapid recharge of water from the surface via discrete pathways linked to highly conductive, solutionally enlarged conduits alongside strong aquifer heterogeneity. Consequently, rapid changes in microbial water quality, which are difficult to monitor with expensive and time-consuming conventional microbiological methods, are a major concern in karst environments. This study examined flow cytometric (FCM) fingerprinting of bacterial cells in groundwater together with fecal indicator bacteria (FIB) at nine separate karst springs of varying catchment size over a 14 month period in order to assess whether such a technique can provide faster and more descriptive information about microbial pollution through such karst aquifer systems. Moreover, the data have also been evaluated with respect to the potential of using turbidity as an easy-to-measure proxy indicator of microbial pollution in a novel way. We argue that FCM provides additional data from which enhanced insights into fecal pollution sources and its fate and transport in such karst catchments can be gained. We also present valuable new information on the potential and limitations of turbidity as an indicator of fecal groundwater contamination in karst. FCM has the potential to become a more widely used tool in the field of contaminant hydrogeology.
含水层的微生物污染是一个全球性的持久性水质问题，对公众健康构成重大风险。岩溶含水层系统极易受到粪便污染源的污染，这是由于地表水通过与高导水性、经溶蚀扩大的管道相连的离散路径快速补给，同时含水层具有很强的非均质性。因此，微生物水质的快速变化是岩溶环境中的一个主要问题，而用昂贵且耗时的传统微生物方法很难对其进行监测。本研究在14个月的时间里，对九个不同集水面积的岩溶泉的地下水中细菌细胞以及粪便指示菌进行了流式细胞术（FCM）指纹识别，以评估这种技术是否能通过此类岩溶含水层系统提供关于微生物污染的更快且更具描述性的信息。此外，还以一种新的方式对浊度作为微生物污染易于测量的替代指标的潜力进行了数据评估。我们认为，流式细胞术提供了额外的数据，从中可以更深入地了解粪便污染源及其在这种岩溶集水区中的归宿和运移情况。我们还提供了关于浊度作为岩溶地区粪便地下水污染指标的潜力和局限性的宝贵新信息。流式细胞术有潜力成为污染物水文地质学领域更广泛使用的工具。
