粗略分辨率的烧毁区域数据集严重低估了与火灾相关的森林损失
Amin Khairoun1, Florent Mouillot2, Wentao Chen2
1Universidad de Alcalá, Environmental Remote Sensing Research Group, Department of Geology, Geography and the Environment, Colegios 2, 28801 Alcalá de Henares, Spain.
The Science of the total environment
|February 3, 2024
概括
中等分辨率的烧毁面积 (BA) 数据显示,撒哈拉以南非洲地区的森林损失超过46%是由火灾造成的,是之前估计的两倍多. 小火,特别是在碎片化的热带森林中,显著推动了随后的树木覆盖损失.
科学领域:
- 林业林业 林业 林业 林业
- 遥感 遥感 遥感 遥感
- 生态生态学 生态生态学
背景情况:
- 全球燃烧面积 (BA) 产品通常使用粗略的分辨率 (≥250 m),可能低估了小型火灾 (<100 公).
- 这种低估可能导致对火灾对森林损失的影响进行不准确的评估,特别是在热带地区.
研究的目的:
- 在撒哈拉以南非洲 (SSA) 分析与火灾相关的森林覆盖面损失,使用高分辨率的Sentinel-2 BA数据 (20 m).
- 为了比较来自中分辨率BA的火灾影响估计,与来自粗分辨率产品的火灾影响估计.
- 调查火灾特征和景观碎片化对森林丧失的影响.
主要方法:
- 在2016年和2019年为SSA使用了来自Sentinel-2卫星数据 (20米分辨率) 的BA产品.
- 将遗漏错误与现有的粗分辨率BA产品进行比较.
- 分析了被烧毁的地区,随后的森林损失,火灾规模,火灾季节和景观碎片化之间的关系.
主要成果:
- 火灾导致SSA森林总损失的46%以上,超过粗分辨率BA产品估计的两倍多.
- 与未燃烧的森林相比,被烧毁的森林面积的后续损失可能性是两倍以上.
- 小火,特别是在森林边缘附近的碎片化景观中,是火灾后森林损失的主要驱动因素.
结论:
- 中等分辨率的BA产品对于准确评估森林生态系统的火灾影响至关重要,特别是在热带地区.
- 火灾的大小,季节和景观碎片化是决定森林覆盖面在燃烧后命运的关键因素.
- 由于粗放度BA数据的局限性,以前估计的与火灾相关的森林损失可能被低估了.
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