Collaborative Research: RAPID: Short-and Long-term Sediment Dynamics Following Wildfire in Chaparral Environments

这个RAPID项目的重点是生产和交付干散纤维，这是美国西部陡坡火灾后的一种典型和即时反应。干砾石层是在旱季的搬运过程中产生的，砾石沉积物在重力作用下沿山坡向下移动，被植被截留。这种材料提供了一个重要的沉积物来源进入河道后，野火在查帕拉尔环境。调查人员将量化2013年5月期间在加州南部烧毁大西卡莫尔峡谷的斯普林斯大火导致沿着通道边缘沉积的干碎屑沉积物的体积。在雨季（通常在10月1日左右开始）前后进行的地面激光扫描将捕捉到景观地形的初始变化。这些数据将通过实地调查得到补充。在火灾后的第一年收集的数据是很重要的发展模型的动态干松散。调查人员拥有大西卡莫尔峡谷和附近两个具有不同火灾历史的类似盆地的25年以上的地貌数据-北叉马蒂利亚河的一条支流在1985年7月的惠勒火灾中完全燃烧-以及马里布河的一条支流仍未燃烧。在这三个站点比较干拆散过程将使短期和长期的沉积物动力学的直接比较后，野火在查帕拉尔环境。对野火的短期和长期影响进行预测性理解至关重要，特别是在气候变化导致野火发生频率和规模增加的时代。然而，准确预测火灾后的影响仍然是难以捉摸的，基于物理的火灾后径流和侵蚀模型仍在开发中。拟议的项目将通过涉及海峡群岛加州州立大学（CSUCI）的本科生来整合研究和教育。这些学生将继续他们的顶点本科课程，同时协助现场数据收集和分析的PI。其中两名学生是CSUCI校园内西班牙裔服务机构ACCESO（通过STEM机会实现合作大学教育）研究助理计划的参与者。这些学生将获得宝贵的研究经验，包括使用尖端技术的培训。

This RAPID project focuses on production and delivery of dry ravel, a characteristic and immediate post-fire response on steep slopes in the western USA. Dry ravel arises from a dry-season transport process whereby gravel sediment moving down hillslopes by gravity becomes trapped by vegetation. This material provides a significant sediment source into river channels after wildfire in chaparral environments. The investigators will quantify the volume of dry ravel sediment deposited along channel margins as a result of the Springs Fire that burned Big Sycamore Canyon in southern California during May 2013. Terrestrial laser scanning before and after the rainy season (which typically begins around October 1) will capture initial changes in landscape topography. These data will be augmented by field surveys. Data collected during the first post-fire year are important for developing models of the dynamics of dry ravel. The investigators have geomorphic data spanning over 25 years for Big Sycamore Canyon and two comparable basins nearby with different fire histories--a tributary to north fork Matilija Creek that burned completely during the July 1985 Wheeler Fire-- and a tributary to Malibu Creek that has remained unburned. Comparing dry ravel processes at these three sites will enable a direct comparison of both short- and long-term sediment dynamics following wildfire in chaparral environments. Developing a predictive understanding of both short- and long-term effects of wildfire is critical, especially in an era of changing climate that has increased frequencies and magnitudes of wildfires. Yet, accurately predicting post-fire effects remains elusive, and physically-based models of post-fire runoff and erosion are still being developed. The proposed project will integrate research and education by involving undergraduate students from California State University, Channel Islands (CSUCI). These students will pursue their capstone undergraduate coursework while assisting the PIs with field data collection and analysis. Two of these students are participants of the Hispanic-Serving Institutes ACCESO (Achieving a Cooperative College Education Through STEM Opportunities) Research Assistant Program on the CSUCI campus. These students will receive valuable research experiences including training in use of cutting-edge technologies.