RAPID: Post-Wildfire Runoff from Burned Urban Coastal Landscape

野火是一场多方面的灾难。2023年8月8日，西毛伊岛拉海纳发生了一场意想不到的野火，这在夏威夷是前所未有的。大火烧毁了无人管理的草原和城市景观，增加了火灾后径流影响的复杂性和不确定性。由此产生的灰烬和污染物对拉海纳的居民和生计都是有害的。环境被火山灰、过量的沉积物和污染物所覆盖。来自陆地的径流将流入三角洲和沿海地貌，影响海洋和河流的地球化学以及沿海生态系统。这一独特的前农业和城市景观的非线性和复杂属性使得如果不立即采样，记录和继续研究燃烧流域的演变，很难预测。当夏威夷进入雨季（从10月开始）时，预计会有暴风雨，这一点尤其正确，因为之前没有观测数据存在。可预见的风暴将导致燃烧地区的灰烬被冲走，沉积物被侵蚀到近岸地区，并破坏生物多样性和渔业。在这个RAPID项目中，PI寻求调查和安装仪器，以收集拉海纳野火后的暴雨径流和沉积物样本。通过及时记录和传播易腐和时间敏感的火灾后数据，本研究使受影响的居民能够根据他们的即时安全和长期环境福祉做出明智的决定。该RAPID项目旨在解决对夏威夷西毛伊岛拉海纳地区野火后影响数据取样的迫切需求。2023年8月8日，毁灭性的野火对这座历史悠久的沿海城市来说是一场意想不到的、前所未有的灾难，并为研究火灾后的径流动态、沉积和污染物在火山、陡峭和城市景观中的运输提供了机会。该项目采用实地和实验室方法收集有关水质、沉积物通量以及土壤和灰分样本的数据。将沿着卡霍马河收集离散的水样和浊度测量，并将在更广泛的拉海纳地区收集陆地土壤和灰烬样本。自动采样器将安装在Kahoma Stream中，以方便长期跟踪。使用自动采样器可以在多个风暴事件中连续收集样本，以代表燃烧景观中的河流沉积物通量。这些数据通过社区参与、已建立的科学渠道和网络地理信息系统门户网站传播，将增强我们对野火对沿海生态系统、珊瑚礁、生物多样性和渔业影响的认识。这项研究有助于新兴的环境科学对灾害恢复能力的研究。通过关注一场罕见的、靠近沿海地区的城市野火，该项目提供了一个独特的视角，通过它来理解野火、水文系统和生态反应之间复杂的相互作用。这项研究提高了我们对火灾后动力学的基础知识，并促进了由于气候变化而面临日益增加的野火风险的类似沿海地区的预测模型和缓解策略的发展。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Wildfire is a disaster in multiple facets. On Aug 8, 2023, the unexpected wildfire in Lahaina West Maui was unprecedented for Hawai‘i. The fire that burned across unmanaged grasslands and urban landscapes adds complexity and uncertainty to the impact of post-fire runoff. The resulting ash and contaminants are detrimental to residents and livelihood in Lahaina. The environment is covered in ash, excessive sediment, and contaminants. Runoff from the land will drain into deltaic and coastal geomorphology, affecting marine and riverine geochemistry and coastal ecosystems. The non-linear and complex attributes of this unique former agricultural and urban landscape make it challenging to predict without immediate sampling, documenting and continued studying of the evolvement of the burned watershed. This is particularly true when storms are anticipated as Hawai‘i is entering its rainy season (starting from October), for which no prior observational data exists. The foreseeable storms will cause undesirable ash wash-off from burned areas and sediment erosion to the near-shore and damage the biodiversity and fisheries. For this RAPID project, the PI seeks to survey and install instruments to collect storm runoff and sediment samples after the wildfires in Lahaina. By promptly documenting and disseminating perishable and time-sensitive post-fire data, this research empowers affected residents with the knowledge to make informed decisions regarding their immediate safety and long-term environmental well-being.This RAPID project proposes to address the pressing need to sample the data of post-wildfire impact in Lahaina West Maui, Hawai‘i. The devastating wildfire on August 8, 2023, was an unexpected and unprecedented disaster to this historical coastal city and presents an opportunity to investigate post-fire runoff dynamics, sedimentation, and contaminant transport in a volcanic, steep, and urban landscape. This project employs field and laboratory methods to collect data on water quality, sediment fluxes, and soil and ash samples. Discrete water samples and turbidity measurements will be collected along the Kahoma Stream and terrestrial soil and ash samples will be collected across the broader Lahaina region. Autosamplers will be installed within Kahoma Stream to facilitate long-term tracking. Using autosamplers allows for the collection of continuous samples over multiple storm events to represent fluvial sediment fluxes from the burned landscape. The data, disseminated through community engagement, established scientific channels, and a web-GIS portal, will enhance our knowledge of wildfire impacts on coastal ecosystems, coral reefs, biodiversity, and fisheries. This study contributes to the emerging environmental science on disaster resilience. By focusing on a rare, urban wildfire with proximity to a coastal area, this project offers a unique lens through which to understand the intricate interplay between wildfires, hydrological systems, and ecological responses. This research advances our fundamental knowledge of post-fire dynamics and facilitates the development of predictive models and mitigation strategies for similar coastal regions facing increasing wildfire risks due to climate change.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.