Collaborative Research: RAPID: Investigating the magnitude and timing of post-fire sediment transport in the Texas Panhandle

德克萨斯州历史上最大的野火最近烧毁了超过110万英亩(4450平方公里)的土地，摧毁了整个德克萨斯州狭长地带的牲畜、农作物、野生动物、房屋和牧场基础设施。人们对野火对泥沙输送的影响进行了充分的研究，结果表明，植被的缺乏和焚烧土壤的疏水特性创造了在随后的降雨事件中加剧陆上水流的条件，并可以动员大量细小的泥沙并引发泥石流。然而，这种对火灾后水文和地貌过程的理解大多来自陡峭(30度)和森林景观。德克萨斯州狭长地带低坡度(1-10度)草原和灌木丛景观的火灾后过程尚不清楚。该项目将为联邦分类的关键栖息地的管理提供重要的数据，该栖息地是濒危鱼类胡椒鱼的栖息地。该项目支持德克萨斯州三所拉美裔服务机构的本科生研究。这项研究对于了解灌木丛火灾后沉积物迁移的规模和时间至关重要。这项工作的一个主要贡献将是收集到像德克萨斯州狭长地带这样的低坡度环境中的第一批火灾后泥沙输送测量数据。泥沙颗粒大小和风化层厚度的测量将提供泥沙运移速率受陆面径流或泥沙有效性施加的应力限制的程度。该项目还将限制植被在低坡度环境中作为间歇性火灾中介储存地点的重要性。最后，对加拿大河流和梅雷迪斯湖悬浮泥沙的测量将限制来自山坡和支流的细颗粒泥沙到达梅雷迪斯湖沉淀池的运输时间。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The largest wildfires in Texas history recently burned more than 1.1 million acres (4,450 square kilometers), and have devastated livestock, crops, wildlife, homes, and ranching infrastructure across the Texas Panhandle. The effects of wildfire on sediment transport are well studied, and indicate that the absence of vegetation and hydrophobic characteristics of burned soils create conditions that intensify overland flow during subsequent rain events and can mobilize large volumes of fine sediment and initiate debris flows. However, much of this understanding of post-fire hydrologic and geomorphic processes is derived from steep (30 degrees) and forested landscapes. Post-fire processes in the lower-slope (1–10 degrees) grassland and shrubland landscapes of the Texas Panhandle are unknown. This project will contribute important data for management of federally classified critical habitat that hosts an endangered fish species, the peppered chub. The project supports undergraduate research at three Hispanic Serving Institutions across Texas.This study is crucial for understanding the magnitude and timing of post-fire sediment transport in shrublands. A major contribution of this work will be the collection of the first post-fire sediment transport measurements in low-sloping environments like the Texas Panhandle. Measurements of sediment grain size and regolith thickness will inform the degree to which sediment transport rates are limited by stress exerted by overland flow or sediment availability. This project will also constrain the importance of vegetation as an intermittent fire-mediated storage site in low-sloping environments. Finally, measurements of suspended sediment in the Canadian River and Lake Meredith will constrain the transport timescales for fine sediment from hillslopes and tributaries to reach the sediment sink of Lake Meredith.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.