Synergistic fire and floodplain solutions

协同火灾和洪泛区解决方案

• 批准号: NE/V021443/1
• 负责人: Richard Field
• 金额: $ 6.67万
• 依托单位: University of Nottingham
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FV021443%2F1
• 关键词: Synergistic; fire; floodplain; solutions

Wildfires, already a major concern in all continents, are forecast to increase in frequency and intensity, impacting parts of the world not previously affected (including the UK under future climate change). Indeed, 2020 was a record year for wildfires globally, and they are estimated to have cost $13 billion in the USA alone (Reuters December 15, 2020). Poor river management practices have contributed to the increased threat of wildfires by drying floodplains, creating a tinderbox effect. For centuries, humans have modified rivers, typically converting multi-channelled rivers into single, deeper channels. This drains and disconnects floodplains, lowers water tables, increases downstream flood risk, and reduces biodiversity by reducing the variety of riverine environments. Changing our approach to river management can therefore have multiple benefits: reduce fires, reduce flooding and increase biodiversity and ecosystem services.Since 2010, floodplain restoration theory has begun to move towards reinstating multiple river channels and increasing wetted area to slow flow velocities and encourage groundwater recharge. This has become known as 'Stage 0' restoration because it aims to return rivers to their natural (pre-human intervention) state. Several sites have been set up to test the effectiveness of the approach, notably the South Fork McKenzie River restoration project in Oregon, USA, which started in 2017. One third of the floodplain has been restored to date. A $1.2 million data collection programme was established, running for 3 years so far, which includes monitoring of wildlife and vegetation, on the land and in the water, to assess the effectiveness of the restoration, relative to unrestored parts of the floodplain. The project's success has recently led to similar floodplain restoration trials in the UK, notably on National Trust land in Porlock Vale, Somerset.Stage 0 restoration has many potential benefits, but until now it has not even been considered in terms of wildfire. However, this changed dramatically in Sept-Nov 2020, when a major wildfire (the 'Holiday Farm Fire') swept through the South Fork McKenzie area, at its peak burning >60,000 ha in 36 hours. The fire only ceased in late Nov 2020, but limited access to the site has recently been granted to the project team. Initial observations strongly suggest that while other parts of the landscape suffered a severe, uniform burn, the restored areas of the floodplain resulted in a diverse fire mosaic, with many parts suffering little or no fire damage. As well as reduced overall burn severity, the more diverse fire intensity in the restored area may actually have biodiversity benefits and build further ecological resilience, according to recent hypotheses in wildfire ecology. The Holiday Farm Fire therefore provides a unique and time-limited opportunity to investigate the ecological and environmental effects of the interaction between wildfire and Stage 0 floodplain restoration. The project site, with 33% of the floodplain restored and the rest as yet unimproved, combined with the detailed baseline data available and a large, very recent fire event, effectively presents us with a natural landscape-scale experiment. We intend to use this amazing opportunity to test the two hypotheses, and to develop both important new understanding of freshwater and terrestrial biodiversity on floodplains, and practical solutions for managing floodplains under both climate change and increasing wildfire risk.

野火已经成为各大洲的一个主要问题，预计其频率和强度将增加，影响世界上以前未受影响的部分地区（包括未来气候变化下的英国）。事实上，2020 年是全球山火创纪录的一年，估计仅在美国就造成了 130 亿美元的损失（路透社，2020 年 12 月 15 日）。河流管理不当导致洪泛区干燥，造成火药桶效应，从而增加了野火的威胁。几个世纪以来，人类一直在改造河流，通常是将多渠道的河流转变为单一的、更深的渠道。这会排干和切断洪泛区，降低地下水位，增加下游洪水风险，并通过减少河流环境的多样性来减少生物多样性。因此，改变我们的河流管理方法可以带来多重好处：减少火灾、减少洪水、增加生物多样性和生态系统服务。自 2010 年以来，洪泛区恢复理论已开始转向恢复多个河道和增加湿润面积，以减缓流速并鼓励地下水充电。这被称为“第 0 阶段”恢复，因为它的目的是使河流恢复到自然（人类干预前）状态。已经设立了多个地点来测试该方法的有效性，特别是 2017 年启动的美国俄勒冈州南福克麦肯齐河修复项目。迄今为止，三分之一的洪泛区已得到修复。建立了一项耗资 120 万美元的数据收集计划，迄今已运行 3 年，其中包括监测陆地和水中的野生动物和植被，以评估相对于未恢复的洪泛区部分的恢复效果。该项目的成功最近在英国进行了类似的洪泛区恢复试验，特别是在萨默塞特郡波洛克谷的国家信托土地上。0 阶段恢复有许多潜在的好处，但到目前为止，它甚至还没有被考虑到野火方面。然而，这种情况在 2020 年 9 月至 11 月发生了巨大变化，当时一场重大野火（“假日农场火灾”）席卷了南福克麦肯齐地区，最高峰时 36 小时内燃烧面积超过 60,000 公顷。大火于 2020 年 11 月下旬才停止，但项目团队最近获得了有限的进入现场的许可。初步观察强烈表明，虽然景观的其他部分遭受了严重、均匀的烧毁，但洪泛区的恢复区域却形成了多样化的火灾马赛克，许多部分几乎没有遭受火灾损坏。根据野火生态学的最新假设，除了总体烧伤严重程度降低外，恢复区域更加多样化的火灾强度实际上可能具有生物多样性效益，并进一步增强生态恢复能力。因此，假日农场火灾提供了一个独特且限时的机会来调查野火与第 0 阶段洪泛区恢复之间相互作用的生态和环境影响。该项目现场 33% 的洪泛区已得到恢复，其余部分尚未得到改善，结合现有的详细基线数据和最近发生的一次大型火灾事件，有效地向我们展示了一次自然景观规模的实验。我们打算利用这个绝佳的机会来检验这两个假设，并发展对洪泛区淡水和陆地生物多样性的重要新认识，以及在气候变化和不断增加的野火风险下管理洪泛区的实用解决方案。

项目成果

A possible role for river restoration enhancing biodiversity through interaction with wildfire

河流恢复通过与野火相互作用增强生物多样性的可能作用

• DOI: http://dx.10.1111/geb.13555
• 发表时间: 2022
• 期刊: Global Ecology and Biogeography
• 影响因子: 6.4
• 作者: Pugh B