Impacts of wildfire on soil erosion and fine-grained sediment dynamics in forested aquatic systems

野火对森林水生系统土壤侵蚀和细粒沉积物动态的影响

• 批准号: 341995-2007
• 负责人: Owens, Philip
• 金额: $ 1.46万
• 依托单位: University of Northern British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2010
• 资助国家: 加拿大
• 起止时间: 2010-01-01 至 2011-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=458692
• 关键词: Impacts; wildfire; soil; erosion; fine

Wildfire events have a significant and measurable impact on the sediment dynamics of forested catchments over wide spatial and temporal scales. This project will determine the response of sediment sources and evaluate sediment (mineral and organic) redistribution through aquatic systems due to wildfires in northern interior forest environments in Canada over contrasting spatial and temporal scales. A successful feasibility study in 2004 indicated that the sediment system in one of the study catchments to be investigated is responding to wildfire disturbance, as evidenced by changing sediment sources and sediment fluxes following a wildfire. The present project will apply a suite of integrated techniques to link contemporary responses to long term recovery from wildfire disturbance. Specifically, a field sampling and laboratory programme will be undertaken comprising three interlinked parts: (a) measurement and sampling on a hillslope unit before and after a prescribed (i.e. induced) burn, (b) a paired-catchment comparative study (i.e. a naturally burnt catchment and a nearby unburnt catchment with similar characteristics) and (c) a palaeolimnological study exploring changes in deposited sediment properties in lake catchments with known fire histories. Work will be undertaken in study areas of contrasting spatial scale (hillslope to catchment) and fire history (present, recent, decades and centuries). The results of these will be utilised to understand the response of catchments to fire in order to link short-term process knowledge with longer term data on sedimentary processes, in order to provide tools for investigating scenarios of potential impacts of burning in forests.

野火事件在广泛的时空尺度上对森林流域的沉积物动态产生重大且可测量的影响。该项目将确定沉积物来源的响应，并在对比的空间和时间尺度上评估加拿大北部内陆森林环境中野火导致的沉积物（矿物和有机）通过水生系统的重新分布。 2004 年一项成功的可行性研究表明，要调查的一个研究流域的沉积物系统正在对野火扰动做出反应，野火后沉积物来源和沉积物通量的变化就证明了这一点。本项目将应用一套综合技术，将当代应对措施与野火干扰的长期恢复联系起来。具体来说，将进行现场采样和实验室计划，包括三个相互关联的部分：(a) 在指定（即诱导）燃烧之前和之后对山坡单元进行测量和采样，(b) 配对流域比较研究（即自然燃烧）烧毁的流域和附近具有类似特征的未烧毁的流域）以及（c）一项古湖泊学研究，探索具有已知火灾历史的湖泊流域沉积物特性的变化。工作将在对比空间规模（山坡到流域）和火灾历史（当前、最近、几十年和几个世纪）的研究领域进行。这些结果将用于了解集水区对火灾的反应，以便将短期过程知识与沉积过程的长期数据联系起来，从而为调查森林燃烧的潜在影响场景提供工具。