Fine sediment impacts on water treatability in fire impacted watersheds: Quantification of downstream propagation and water quality threats

森林是加拿大超过58%的最大城市和农村社区以及大多数土著社区的主要饮用水来源。具有讽刺意味的是，这些水资源的高质量使他们容易受到严重的大规模景观干扰，如野火产生的。在过去的二十年里，与气候相关的火灾天气条件的变化导致北美西部关键森林水源地区主要野火干扰的发生率、范围和严重程度迅速增加。野火对森林地区河流的沉积物和相关营养动态的威胁可能对加拿大许多地区和地球仪的供水和生态系统服务构成真实的风险。尽管野火具有经济和环境意义，并威胁到安全饮用水的供应，但相对较少的研究审查了细沉积物在河流中的传播，以及这些物质向水库的输送。关于这种沉积的底部沉积物是磷的汇还是磷的源，或者它是否有可能增殖蓝细菌的生长，这可能会挑战水处理过程，人们知之甚少。考虑到森林融雪为主的落基山脉东坡的斜坡是加拿大和美国的关键供水地区，从这项研究中获得的知识是相关的水源沃茨一般来自森林景观的供水商。拟议的研究结果将提高运输过程和火灾后沉积物和相关的磷在大流域尺度的河流水质影响的知识，并评估在下游环境，如湖泊和水库水质的风险。从拟议的研究中获得的知识将提供科学见解，为水库管理战略提供信息，以评估野火细沉积物对水可处理性的风险以及提供安全饮用水的相关挑战。

Forests are the primary source of drinking water for > 58% of the largest urban and rural communities as well as most Indigenous communities in Canada. Ironically, the high quality of these water resources make them vulnerable to severe large scale landscape disturbance such as those produced by wildfire. Climate associated changes in fire weather conditions over the past two decades have resulted in rapidly increasing occurrence, extent, and severity of major wildfire disturbances in critical forested source water regions of western North America. The threat of wildfire on sediment and associated nutrient dynamics in rives draining forested regions may pose a real risk to water supply and ecosystem services in many regions in Canada and across the globe. Despite the economic and environmental significance of wildfire and threats to the provision of safe drinking water, relatively few studies have examined the propagation of fine sediment in rivers draining burned watersheds and the delivery of these materials to reservoirs. Little is known about whether this deposited bottom sediment is a sink or source of phosphorus or if it has the potential to proliferate the growth of cyanobacteria which can challenge water treatment processes. Given that forested snow melt dominated slopes of the eastern slopes of the Rocky Mountains are critical water supply regions in Canada and the United States, knowledge gained from this research is relevant to water suppliers where source waters generally originate from forested landscapes. Results of the proposed research will improve knowledge of the transport processes and water quality impacts of post fire sediment and associated phosphorus in rivers at the large basin scale and evaluate the risk to water quality in downstream environments such as lakes and reservoirs. Knowledge gained from the proposed research will provide scientific insights to inform reservoir management strategies to evaluate the risk of fine sediment from wildfires to water treatability and related challenges to the provision of safe drinking water.