Innovative multifaceted approaches for tracing the sources and fate of nutrients and contaminants in watersheds

含氮(N)和磷(P)的化合物有可能引起严重的水质退化，影响饮用水质量，并可能导致大陆水体富营养化。农业肥料、城市径流和废水以及工业点源中的氮和磷导致越来越多的养分释放到地表水和地下水中。追踪流域中N和P化合物的来源、运输和命运仍然是一个重大挑战。这项为期5年的研究计划的目标是开发一种创新的示踪方法，该方法将新型同位素指纹识别工具与更成熟的化学和同位素方法、水年龄测定方法以及领先的微生物学和宏基因组学技术相结合。基于对所调查流域中相关磷和氮来源的同位素指纹的全面清单，本研究计划中使用的科学方法将包括水地球化学和新型和已建立的同位素示踪技术的结合，以确定影响地表水和地下水系统养分负荷的主要来源。此外，我的研究小组将提高我们的能力，揭示影响这些营养物质在被调查的水生系统中的发生和持续的生物地球化学反应。为此，将在加拿大西部进行实验室实验和生物反应器微观研究，在人工溪流和实验性废水处理厂中进行有控制的营养物追踪，以及在整个流域范围内对地表水和地下水进行研究。将使用宏基因组学、RNA和蛋白质测序等前沿技术以及其他微生物学方法来获得补充证据，以确定在所调查的水生系统中控制营养物质的命运和污染物的持久性所涉及的主要过程和关键微生物。此外，水年龄定年技术将被用来获得有关水在被调查的水生系统中的传输时间的见解。这些方法的创新组合预计将大大提高对水生系统中营养物和污染物负荷的来源和时间线的理解，并将对导致地表水和地下水系统中营养物和污染物生物降解的主要过程和近似反应速率产生新的见解。所获得的知识对于制定未来的水管理战略以保护或修复加拿大和其他地方的水生系统至关重要。

Nitrogen (N) and phosphorus (P) containing compounds have the potential to induce major water quality degradations affecting drinking water quality and may cause eutrophication of continental water bodies. N and P in agricultural fertilizers, in urban runoff and wastewater effluents, and from industrial point sources cause increasing nutrient releases into surface water and groundwater bodies. Tracing the sources, the transport and the fate of N and P compounds in watersheds remains a major challenge. The objective of this 5-year research program is to develop an innovative tracer approach that combines novel isotope fingerprinting tools with more established chemical and isotopic approaches, water age-dating methods, and leading-edge microbiological and metagenomic techniques. Based on a thorough inventory of isotopic fingerprints of P and N sources relevant in the investigated watersheds, the scientific approach used in this research program will be comprised of a combination of aqueous geochemistry and novel and established isotopic tracer techniques to determine the predominant sources affecting nutrient loading of surface water and groundwater systems. In addition, my research team will advance our capabilities to unravel the biogeochemical reactions that affect the occurrence and persistence of these nutrients in the investigated aquatic systems. This will be achieved by conducting laboratory experiments and bioreactor microcosm studies, controlled nutrient tracing in artificial streams and an experimental wastewater treatment plant, and watershed-wide studies accessing surface water and groundwater bodies in Western Canada. Leading-edge techniques such as metagenomics, RNA and protein sequencing, as well as other microbiological approaches will be used to obtain complementary evidence for identifying the predominant processes and the key microorganisms involved in controlling the fate of nutrients and the persistence of contaminants in the investigated aquatic systems. Furthermore, water age-dating techniques will be employed to gain insights about water transit times in the investigated aquatic systems. The innovative combination of these approaches is expected to yield a much improved understanding of sources and timelines involved in nutrient and contaminant loading of aquatic systems, and will result in novel insights into the predominant processes and approximate reaction rates leading to biodegradation of nutrients and contaminants in surface water and groundwater systems. The obtained knowledge will be essential for developing future water management strategies for safeguarding or remediating of aquatic systems in Canada and elsewhere.