ECO-CBET: Collaborative Research: Effect of surface-fuel attributes and forest-thinning patterns on wildfire, carbon storage, and advancing forest restoration

ECO-CBET：合作研究：地表燃料属性和森林间伐模式对野火、碳储存和推进森林恢复的影响

• 批准号: 2318718
• 负责人: Tirtha Banerjee
• 金额: $ 51.84万
• 依托单位: University of California-Irvine
• 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: 2023-08-01 至 2027-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2318718&HistoricalAwards=false
• 关键词: ECO; CBET; Collaborative; Research; Effect

2318717 (Cobian). In recent years, high-severity wildfires have severely damaged forested mountain watersheds that store carbon, supply western-states’ water, and provide many co-benefits. While periodic low- to medium-severity wildfires are a natural part of western U.S. forests, too much of the area is burning at high severity owing to excessive fuel loads and a warming climate. Therefore, a critical goal of forest management is often the introduction of practices designed to reduce the risk of high severity fires. These practices, known collectively as forest restoration, involve thinning and removing or masticating the less-fire-resistant, smaller trees, while leaving larger, more widely spaced trees. A common restoration approach is applying mechanical thinning followed by mastication which changes the forest-canopy structure and surface-fuel loading and characteristics. While it is known that changing the arrangement and density of trees and other vegetation through mastication affects fire behavior, there is a lack a quantitative understanding of how attributes of masticated fuels affect subsequent fire severity. The goal of this project is to develop metrics of the impact of fuel treatments on fire behavior across a range of spatial and temporal scales. This project will contribute to improved understanding of how surface-fuel attributes, resulting from management decisions, influence fire behavior and severity and thus forest biomass carbon storage.Mechanical thinning followed by mastication changes the forest-canopy structure and surface-fuel loading and characteristics. While these changes can impact fire behavior significantly, their sensitivities to the type and degree of mastication are not well understood. The three main goals of the study are: (1) To establish the importance of heterogeneous and multiscale surface-fuel loadings and attributes, following mechanical fuel treatments, on the temperature, flame length, and spread of fire as these fuels burn; (2) To develop and assess predictive tools for wildfire severity and spread in the forest given these different fuel attributes, under contrasting micro-meteorological conditions; and (3) To demonstrate carbon-storage and related benefits from different fuel treatments designed to reduce the occurrence and impacts of high-severity wildfires. The study will use bench-scale combustion experiments, field measurements involving controlled burns in thinned and masticated stands in a mixed-conifer forest, and modeling of wildland fire and carbon storage. Results from experiments, modeling, and assessment of field-scale control burns will be used to identify key drivers of fire severity in ground fuels following thinning. Primary contributions of the study will be improved understanding of how surface-fuel attributes, resulting from management decisions, influence fire behavior and severity and thus forest biomass carbon storage. Results will improve modeling of flame length, fire spread and carbon balance and storage in the litter, mineral soil, and deeper regolith. This research will engage decision maker and stakeholder partnerships with organizations that are advancing landscape restoration, providing much-needed improvements in projection of how their investments may affect wildfire severity.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.

2318717(科比安)。近年来，严重的野火严重破坏了森林覆盖的山区分水岭，这些分水岭储存碳，供应西部各州的水，并提供许多共同利益。虽然周期性的低到中等严重程度的野火是美国西部森林的自然组成部分，但由于过度的燃料负荷和气候变暖，该地区太多地区正在以高度严重的方式燃烧。因此，森林管理的一个关键目标往往是采用旨在减少严重火灾风险的做法。这些做法统称为森林恢复，包括间伐和移除或咀嚼耐火性较差的较小树木，同时保留较大的、分布较广的树木。一种常见的恢复方法是机械间伐，然后进行咀嚼，这会改变森林冠层结构和地表可燃物负荷和特征。虽然已知通过咀嚼改变树木和其他植物的排列和密度会影响火灾行为，但对于咀嚼燃料的属性如何影响随后的火灾严重程度缺乏定量的了解。该项目的目标是在一系列空间和时间尺度上制定燃料处理对火灾行为的影响的衡量标准。该项目将有助于更好地理解管理决策产生的地表燃料属性如何影响火灾行为和严重程度，从而影响森林生物质碳储存。机械间伐和咀嚼作用改变了森林冠层结构和地表燃料负荷和特征。虽然这些变化会显著影响火灾行为，但它们对咀嚼类型和程度的敏感性尚不清楚。这项研究的三个主要目标是：(1)确定机械燃料处理后不同和多尺度的地面燃料负荷和属性对这些燃料燃烧时的温度、火焰长度和火蔓延的重要性；(2)在不同的微气象条件下，考虑到这些不同的燃料属性，开发和评估野火严重程度和在森林中蔓延的预测工具；(3)展示旨在减少高度严重野火的发生和影响的不同燃料处理的碳储存和相关好处。这项研究将使用实验室规模的燃烧实验、涉及针叶混交林稀疏和咀嚼林中受控燃烧的现场测量，以及荒地火灾和碳储存的建模。来自现场范围控制燃烧的实验、建模和评估的结果将被用来确定稀薄后地面燃料火灾严重程度的关键驱动因素。这项研究的主要贡献将是更好地理解管理决策产生的地表燃料属性如何影响火灾行为和严重程度，从而影响森林生物质碳储存。结果将改进对火焰长度、火蔓延以及凋落物、矿物土壤和更深的风土层中碳平衡和储存的模拟。这项研究将使决策者和利益相关者与正在推进景观恢复的组织建立合作伙伴关系，在预测他们的投资可能如何影响野火严重程度方面提供亟需的改进。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。