RAPID: Investigation of Immediate Post-fire Hydro-geochemical Coupling and Contaminant Flux in an Urban-fringe Watershed in Southern California

RAPID：对南加州城市边缘流域火灾后立即水文地球化学耦合和污染物通量的调查

• 批准号: 0965236
• 负责人: Terri Hogue
• 金额: $ 6万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-04-15 至 2011-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0965236&HistoricalAwards=false
• 关键词: RAPID; Investigation; Immediate; Post; fire

The Station fire is currently noted as the largest fire in Los Angeles County history as well as the 10th largest fire in California history. The burned region is located immediately adjacent to dense urban areas on the east side of the Los Angeles basin. These urban-wildland regions, located in the San Gabriel Mountains, will now be impacted by increased flooding, debris and sediment-laden flows, and significant water quality issues. The San Gabriel Mountains are known to receive high loads of atmospheric pollutants (dry and wet)originating from the Los Angeles metropolitan region. Runoff from these mountains normally supplies significant runoff into downstream urban water ways, which is then directed to infiltration ponds or zones for aquifer recharge, or into conveyance channels that route water through dense urban areas to coastal bays. Postfire runoff in these urban-fringe watersheds may now contribute significant, and potentially toxic, chemical loads into downstream urban systems, affecting regional water supplies, biota and ecosystem function. Funds from this RAPID grant will allow an immediate and extensive investigation of storm-driven contaminant flux (including nutrients, metals, PAHs, sediments, and other ancillary parameters) in an urban fringe watershed affected by significant atmospheric deposition and that was burned in its entirety. Previously collected pre-fire data on the study watershed will allow a unique and comprehensive comparison to pre-burn behavior,advance knowledge on post-burn hydro-geochemical coupling and alterations in basin mass loading, and provide critical data to improve geochemical and hydrologic modeling in post-burn systems. The overarching goal of the proposed research is to better understand the mechanisms controlling alterations in the chemical and physical response of urban fringe watersheds after a catastrophic wildfire. Specifically, we propose to address the following science questions: 1) How does post-fire hydro-geochemical coupling (behavior) alter from pre-fire conditions? 2) How does storm variability influence post-fire runoff behavior and coupled contaminant flux? 3) What is the effect of burn on riparian nitrate soil storage and streamwater export? and 4) What is the impact of a catastrophic burn on seasonal pollutant loading to downstream urban systems?

目前，该车站大火是洛杉矶县历史上最大的大火，也是加利福尼亚历史上第10大火灾。被烧毁的地区位于洛杉矶盆地东侧茂密的城市地区附近。这些位于圣加布里埃尔山脉的城市wildland地区现在将受到洪水，碎屑和沉积物的增加以及重大水质问题的影响。众所周知，圣加布里埃尔山（San Gabriel Mountains）接收来自洛杉矶大都会地区的大气污染物（干和湿）。这些山脉的径流通常为下游的城市水路提供大量的径流，然后将其定向到浸润池塘或含水层补给的区域，或者进入将通过密集的城市区域供水到沿海湾的运输渠道。现在，这些城市呼声的流域发生后径流现在可能会造成大量且潜在的有毒化学负载，从而影响下游的城市系统，从而影响区域供水，生物群和生态系统功能。这项快速赠款的资金将允许对风暴驱动的污染物通量（包括营养，金属，PAH，沉积物和其他辅助参数）进行直接和广泛的研究，并受到大气层大气层影响的城市边缘流域的影响，并全部燃烧。先前收集的有关研究流域的火前数据将允许与燃烧前的行为进行独特而全面的比较，提高燃烧后水力化学耦合的知识以及盆地质量负荷的改变，并提供关键数据，以改善燃烧后系统中的地球化学和水平模型。拟议的研究的总体目标是更好地了解控制灾难性野火后城市边缘流域化学和物理反应改变的机制。具体来说，我们建议解决以下科学问题：1）后火力 - 地球化学耦合（行为）如何从发生前的条件中改变？ 2）风暴的变异如何影响发生后径流行为和耦合污染物助焊剂？ 3）燃烧对河堤硝酸盐土壤储存和溪流出口的影响是什么？ 4）灾难性燃烧对季节性污染物对下游城市系统的负载有什么影响？