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基于森林火灾在峡谷风场传播的数值模拟的灭火危险的定量评估方法
Ao Wang1, Chenghu Wang1,2, Guiyun Gao1,2
1National Institute of Natural Hazards, Ministry of Emergency Management, Beijing, China.
PloS one
|July 24, 2025
概括
森林消防在山区的地形上是复杂的. 这项研究使用建模来评估火灾行为和风险,发现草原构成最高危险.
科学领域:
- 环境科学 环境科学
- 林业 林业 林业 林业 林业
- 地理空间分析是什么
背景情况:
- 山区和峡谷地区具有复杂的地形和可变的风,增加森林火灾风险.
- 穆利森林大火 (2020年3月28日) 强调了需要在这些地区进行先进的风险评估.
研究的目的:
- 用专门的建模软件模拟风场并评估森林火灾行为.
- 开发和应用一个全面的森林防火风险评估模型.
- 分析不同地形和植被类型的风险变化.
主要方法:
- 使用WindNinja软件进行山谷风场模拟.
- 采用FARSITE软件来建模火灾传播速度,火线强度和火焰长度.
- 开发了一个风险评估模型,包括火灾行为,燃料类型,地形和脆弱性指数,使用分析层次过程进行索引权重.
主要成果:
- 16%和54%的研究区域分别显示高和危险的火灾传播率.
- 在5.9%的地区和0.14%的地区发现了高和极其危险的火线强度.
- 草原的平均灭火危险指数最高 (11),其次是叶大叶 (10.3) 和常青针叶树林 (7.4).
- 该地区16.5%和21.4%的地区分别面临高和极高的灭火危险水平.
结论:
- 草原是消防预防和伤亡减轻的关键区域,因为它具有最高的危险指数.
- 开发的风险评估模型有效地确定了针对性灭火战略的高风险区域.
- 了解不同地形和植被的火灾行为和风险变化对于有效的森林火灾管理至关重要.
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