CAREER: The Legacy of Wildfire on Carbon Watershed Biogeochemistry

职业生涯：野火对碳流域生物地球化学的影响

• 批准号: 1942068
• 负责人: Rebecca Barnes
• 金额: $ 84.92万
• 依托单位: Colorado College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-05-01 至 2023-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1942068&HistoricalAwards=false
• 关键词: CAREER; Legacy; Wildfire; Carbon; Watershed

Wildfires occur more regularly and with greater severity throughout the western United States. In addition to threatening our safety, these fires also change ecosystems. Severe fires release large amounts of carbon into the atmosphere, contributing to climate change. Wildfires also change the way carbon and water move and are stored within ecosystems. This project aims to understand how severe fire alters the movement and fate of carbon from land to water over multiple timescales and forest types. Field observations, laboratory experiments, and computer models will quantify the size and fate of terrestrial and aquatic carbon pools. Results will improve our ability to understand the feedbacks between a changing climate, increasing wildfires, and forest carbon cycling. In addition, this project will create a partnership between Colorado College, a small liberal arts school, and two large research focused universities: University of Utah and Texas A&M University. This partnership will provide increased opportunities for undergraduates, providing research experiences both within and outside the classroom. The project will train more than 75 undergraduate students and two postdoctoral scholars. Results from this project will be shared with the Colorado Springs community through an outreach-oriented exhibit at the Fine Arts Center at Colorado College via a partnership with an artist. Severe fire results in large shifts in terrestrial ecosystem carbon (C) stocks and alters watershed hydrology, shifting flow paths and thus the sources and processing of organic matter to aquatic ecosystems. Currently, terrestrial ecosystem C models do not adequately incorporate inland waterways, resulting in a significant overestimate of net ecosystem production, i.e. the size of the terrestrial C sink. The overarching goal of this research is to better understand how disturbance alters C processing along flow paths within the terrestrial environment and the fate of C within aquatic ecosystems. The project will leverage field campaigns, seasonal and year-round precipitation and stream water collection, controlled laboratory experiments, and modeling efforts at four sites across Colorado that form a “natural experiment”. Project study sites include two subalpine sites and two montane sites, each consisting of one landscape with tree reestablishment and one with few to no established seedlings or saplings, almost 20 years post fire. C stocks and processes will be quantified and characterized across these gradients to better identify causal relationships that will help predict how ecosystems will respond to ongoing and future disturbance. Further, project results will have important implications for incorporating disturbance and aquatic systems into ecosystem C models, with the potential to inform paleoecological reconstructions of fire’s impact on ecological processes.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.

美国西部地区野火发生的频率更高、严重程度也更高。除了威胁我们的安全外，这些火灾还改变了生态系统。严重的火灾会向大气中释放大量碳，导致气候变化。野火还改变了生态系统中碳和水的移动和储存方式。该项目旨在了解严重火灾如何改变碳在多个时间尺度和森林类型中从陆地到水中的移动和命运。现场观察、实验室实验和计算机模型将量化陆地和水生碳库的大小和命运。结果将提高我们理解气候变化、野火增加和森林碳循环之间反馈的能力。此外，该项目还将在科罗拉多学院（一所小型文理学院）与两所大型研究型大学（犹他大学和德克萨斯农工大学）之间建立合作伙伴关系。这种伙伴关系将为本科生提供更多机会，在课堂内外提供研究经验。该项目将培养超过75名本科生和两名博士后学者。该项目的成果将与一位艺术家合作，通过在科罗拉多学院美术中心举办的外展展览与科罗拉多斯普林斯社区分享。严重火灾会导致陆地生态系统碳（C）储量发生巨大变化，并改变流域水文，改变水流路径，从而改变水生生态系统有机物的来源和加工过程。目前，陆地生态系统碳模型没有充分纳入内陆水道，导致净生态系统生产（即陆地碳汇的规模）显着高估。这项研究的首要目标是更好地了解干扰如何改变陆地环境中碳沿流动路径的处理以及水生生态系统中碳的命运。该项目将利用实地活动、季节性和全年降水和溪流收集、受控实验室实验以及科罗拉多州四个地点的建模工作，形成“自然实验”。项目研究地点包括两个亚高山地点和两个山地地点，每个地点都由一处树木重建的景观和一处几乎没有幼苗或树苗的景观组成，距火灾发生近 20 年。碳库和过程将在这些梯度上进行量化和表征，以更好地确定因果关系，这将有助于预测生态系统将如何应对当前和未来的干扰。此外，项目结果将对将干扰和水生系统纳入生态系统 C 模型产生重要影响，并有可能为火灾对生态过程影响的古生态重建提供信息。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。