Wildfire and vegetation impacts on sediment transport and hillslope evolution in mountain landscapes

野火在加拿大许多地区是一个严重的危险，当大火蔓延到定居点和发达地区时，构成特别重大的威胁。近年来严重的野火突显了加强对野火如何引发、传播和影响环境的了解的必要性。尽管野火给人类带来了危险，但野火是一种自然形式的干扰，是环境的重要组成部分；生态系统和野生动物已经适应并依赖于野火的发生。随着森林地面燃料的积累，扑灭野火不仅可能增加未来火灾的严重性，而且还会扰乱自然生态系统的运行。需要更好地了解野火行为和火灾后对自然系统的影响，以确保采取健全的管理战略。野火可能会导致地面植被和/或树木的死亡，并可能改变土壤化学物质，从而减少土壤中的水分渗透。因此，可能会对地表以下和上方以及河流中的水的运动进行修改。这些变化可能导致土壤侵蚀和/或滑坡加剧，从而增加河流的泥沙负荷。这种变化可能会对水质和鱼类栖息地造成不利影响。滑坡速度的增加也对人类住区和基础设施构成了威胁。此外，由于温室气体变暖，野火的发生与气候变化之间存在很强的联系，某些地区的火灾活动和严重程度可能会增加。这项研究的任务是更好地了解野火对自然系统运行的影响。这项工作通过实地调查研究了加拿大落基山脉的火灾后侵蚀。此外，利用数值模拟模拟评估了景观对未来气候变化的响应和对野火制度的相关修改。承担这项工作的研究小组将产生非常重要的结果，这对科学界和考虑火灾后侵蚀的环境管理人员将是有价值的。结果还将提供更长时间尺度上的自然、火灾后侵蚀过程的基线信息，并允许对景观进行战略性的长期管理。

Wildfire is a serious hazard in many parts of Canada, posing a particularly significant threat when fires spread to settlements and developed locations. Severe wildfires in recent years have highlighted the necessity for improved understanding of how wildfires initiate, spread and impact the environment. Despite the hazard they present to humans, wildfires are a natural form of disturbance and are a critical part of the environment; ecosystems and wildlife have adapted to and rely on wildfire occurrence. Wildfire suppression may not only increase the severity of future fires as fuels on the forest floor accumulate, but it disrupts natural ecosystem operation. Improved understanding of wildfire behaviour and post-fire effects on natural systems is required to ensure sound management strategies are adopted. Wildfires may lead to death of ground vegetation and/or trees, and may modify soil chemistry, thereby decreasing water infiltration into soils. As a consequence, modifications to water movement below and above the land surface, and in rivers, may occur. These changes may lead to increased soil erosion and/or landsliding, and thereby increase sediment loads in rivers. Such changes may adversely impact water quality and fish habitat. Increased landsliding rates also present a hazard to human settlements and infrastructure. In addition, strong connections exist between wildfire occurrence and climate change due to greenhouse warming, with the possibility of increased fire activity and severity in certain regions. The mission of this research is to better understand impacts of wildfire on natural system operation. This work considers post-fire erosion in the Canadian Rockies through field-based investigations. In addition, landscape response to future climate change and associated modifications to wildfire regimes is assessed using numerical modelling simulations. The research team undertaking this work will produce highly significant results, that will be valuable to the scientific community and to environmental managers considering post-fire erosion. Results will also provide baseline information about natural, post-fire erosional processes over longer times scales, and allow for strategic, long-term management of landscapes.