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估计现场库存采样强度对森林景观模型性能的影响,以确定高严重性野火风险
Hagar Hecht1,2, Dan J Krofcheck3,4, Dennis Carril5
1Spatial Informatics Group Natural Assets Lab, Pleasanton, CA, USA. hechtit@gmail.com.
Scientific reports
|February 6, 2024
概括
在美国西南部优化森林管理需要准确的初始植被数据. 更详细的森林库存地块可以改善野火风险评估,并在模拟中揭示更高的碳吸收潜力.
科学领域:
- 森林生态 森林生态
- 野火管理管理 野火管理
- 适应气候变化 适应气候变化
背景情况:
- 美国西南部的森林历来依赖于火灾,但现在由于火灾排斥和气候变化而面临严重的野火.
- 森林管理采用稀释和处方燃烧来减轻高严重性火灾风险,但这些是昂贵和劳动密集的.
- 景观模拟模型有助于识别高风险区域和评估治疗方法,但模型的不确定性可能会阻碍决策.
研究的目的:
- 调查景观模拟模型的初始植被层中的不确定性.
- 评估库存地块的数量和分布如何影响森林生物质和火灾风险的建模.
- 了解初始植被数据对模拟生态系统碳动态的影响.
主要方法:
- 从圣塔菲火山小屋的前一项研究中获益.
- 利用来自111个森林种群的新库存地块数据来插入初始森林条件.
- 分析了不同数量的库存地块对模拟生物质分布和可变性的影响.
主要成果:
- 增加库存地块的数量改变了地理分布,扩大了模拟森林生物质的范围.
- 根据更新的植被数据,具有高严重火灾高概率的地区的空间分布发生了变化.
- 来自更多地块的生物质变异性更大,导致模拟显示生态系统碳吸收率增加.
结论:
- 最初的森林植被层是影响景观模型中火力学和碳循环的关键因素.
- 初始植被层的准确性和可靠性取决于所使用的库存地块数量及其对森林类型和生物质密度的代表性覆盖面.
- 通过更广泛的地块数据来改进初始森林状况的表征,提高了模拟模型对有效森林管理和碳动态评估的实用性.
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