Collaborative Research: RAPID: Do large recent wildfires in the Yukon River Delta alter the delivery of black carbon to the Arctic Ocean?

合作研究：RAPID：育空河三角洲最近发生的大规模野火是否会改变黑碳向北冰洋的输送？

• 批准号: 2300040
• 负责人: Robert Spencer
• 金额: $ 2.23万
• 依托单位: Florida State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-02-15 至 2025-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2300040&HistoricalAwards=false
• 关键词: Collaborative; Research; RAPID; Do; large

Wildfires produce charcoal, also termed black carbon, which is resistant to breakdown and is environmentally long-lived. A portion of this charred material is dissolved upon interaction with water and is carried away from soils to rivers as dissolved black carbon (DBC). A warmer and drier climate has led to increased wildfire activity in Arctic regions and it is unknown how these changes will affect the amount of DBC in rivers and its fate in the coastal environment. In the summer of 2022, the Apoon Pass and East Fork Fires burned 255,000 acres in the Yukon River Delta (Alaska, USA), part of a trend towards larger and more frequent wildfires in the Delta in recent years. The main goal of this project is to determine whether recent wildfire activity in the Delta leads to increased amounts of DBC along the Yukon River and estuary to the coastal Arctic Ocean. Results of this work will lay the groundwork for future, large-scale studies on fire-derived carbon in vulnerable Arctic watersheds. This project will support collaboration among two early career researchers and one graduate student with guidance from an experienced Arctic investigator.Pan-Arctic watersheds are experiencing increased fire activity as a result of climate change. The cumulative effects of wildfire (charcoal production, soil destabilization, change in hydrologic flow paths) on carbon export in major Arctic rivers is currently unknown. This project will determine whether large, recent wildfires within the Yukon River Delta have changed the distribution, composition, and total export of DBC along the Yukon River-to-Arctic Ocean continuum. To achieve this goal, new samples will be collected during the 2023 spring freshet and results compared to those obtained from archived 2019 freshet samples. We will employ a combination of molecular marker, stable carbon isotope, and ultrahigh resolution mass spectral techniques to evaluate wildfire-DBC relationships in the Yukon River Delta between low-fire (2019; ~10,000 acres burned) and high-fire (2023; 255,000 acres burned) years. This work builds upon other efforts to predict the effects of climate change on carbon cycling in Arctic-boreal landscapes and will assist in answering broad research questions regarding the behavior of DBC in intermediate reservoirs and fate of terrestrial organic matter in the coastal ocean.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.

野火产生木炭，也称为黑碳，它不易分解且对环境寿命长。这种烧焦的物质的一部分在与水相互作用时溶解，并以溶解黑碳 (DBC) 的形式从土壤带到河流中。气候变暖和干燥导致北极地区野火活动增加，目前尚不清楚这些变化将如何影响河流中 DBC 的数量及其在沿海环境中的命运。 2022 年夏季，阿彭山口和东福克大火烧毁了育空河三角洲（美国阿拉斯加州）255,000 英亩的土地，这是近年来三角洲地区野火规模更大、更频繁的趋势的一部分。该项目的主要目标是确定三角洲最近的野火活动是否导致育空河沿岸和北冰洋沿岸河口的 DBC 数量增加。这项工作的结果将为未来对脆弱的北极流域火源碳进行大规模研究奠定基础。该项目将支持两名早期职业研究人员和一名研究生在经验丰富的北极调查员的指导下进行合作。由于气候变化，泛北极流域的火灾活动正在增加。野火（木炭生产、土壤不稳定、水文流路变化）对北极主要河流碳输出的累积影响目前尚不清楚。该项目将确定育空河三角洲最近发生的大规模野火是否改变了育空河至北冰洋连续体沿线 DBC 的分布、组成和出口总量。为了实现这一目标，我们将在 2023 年春季新鲜采集期间收集新样本，并将结果与​​从存档的 2019 年新鲜样本中获得的结果进行比较。我们将结合使用分子标记、稳定碳同位素和超高分辨率质谱技术来评估育空河三角洲低火（2019 年；约 10,000 英亩被烧毁）和高火（2023 年；255,000 英亩）之间的野火与 DBC 关系。烧毁的英亩数）年。这项工作建立在预测气候变化对北极-寒带景观碳循环影响的其他努力的基础上，并将有助于回答有关中间储层中 DBC 行为以及沿海海洋中陆地有机物命运的广泛研究问题。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。