Monitoring microbial fate and transport in subsurface hydrologic systems

本研究计划旨在改善地下微生物的检测和测量方法，以改善水源保护。病原微生物对水资源的污染是一项重大健康风险，但在加拿大，地下水污染的程度和风险在很大程度上是未知的。特别是，如果不能保护浅层、脆弱的地下水资源的质量，可能会产生严重的后果（例如，沃克顿地下水悲剧）。被称为胶体的微生物和其他颗粒可以从陆地表面向下移动，穿过土壤剖面，到达地下水。微生物胶体通过土壤的运动是非常复杂的，相对而言，人们对它们移动的速度和距离知之甚少。这部分是由于缺乏监测土壤带内胶体浓度的适当技术。最近的研究还表明，水传播疾病暴发与大降水事件之间存在联系，但在这些情况下，传统的地下水采样方法对于微生物检测并不可靠。本研究的目的有两个：(1)全面测试和改进地下微生物浓度监测方法；(2)利用这些改进的方法，以便更好地了解野外微生物的运动和生存。将进行实验室实验，以评估不同技术的适用性，包括创新的新的被动和基于生物的方法，以监测土壤和地下水中的微生物。然后将把现有的最佳监测技术应用于加拿大多个实地场址的一系列试验性研究。这项研究将产生有价值的监测水质的新方法，并深入了解地下微生物的运输，从而改善水资源保护并减少对人类健康的风险。

This research program is aimed at improving methods for detecting and measuring microscopic organisms in the subsurface in order to improve source water protection. Contamination of water resources by pathogenic microorganisms is a major health risk, yet the extent and risks of groundwater contamination are largely unknown in Canada. Failure to protect the quality of shallow, vulnerable groundwater sources, in particular, can have serious consequences (e.g., the Walkerton groundwater tragedy). Microscopic organisms and other particles, referred to as colloids, can move from the land surface down through the soil profile and reach groundwater. The movement of microbial colloids through soil is very complex and relatively little is known about how quickly or how far they will move. This is due, in part, to the lack of suitable techniques for monitoring colloid concentrations within the soil zone. Recent studies have also shown linkages between waterborne disease outbreaks and large precipitation events, yet traditional methods of groundwater sampling are not reliable for microbial detection in these instances. The goals of this research are twofold: (1) to comprehensively test and improve methods for monitoring microbial concentrations in the subsurface, and (2) to employ these improved methods in order to better understand the movement and survival of microbes in the field. Laboratory experiments will be conducted to evaluate the suitability of different techniques, including innovative new passive and biologically-based approaches, for monitoring microbes in soil and groundwater. The best available monitoring techniques will then be applied in a series of pilot studies at multiple field sites in Canada. The research will generate valuable new methodologies for monitoring water quality and yield insights into subsurface microbial transport, thereby leading to improved water resource protection and a reduction in the risks to human health.