火灾引起的侵蚀和千年规模的气候变化在北方的Pondorosa松树林
Jennifer L Pierce1, Grant A Meyer, A J Timothy Jull
1Department of Earth and Planetary Science, University of New Mexico, Albuquerque, New Mexico 87131, USA. jpierce@unm.edu
Nature
|November 5, 2004
概括
气候变化正在增加美国西部松树林中严重野火的风险. 历史数据显示,更热的时期与灾难性火灾相关,挑战恢复工作.
科学领域:
- 生态生态学 生态生态学
- 气候科学 气候科学
- 林业林业 林业 林业 林业
背景情况:
- 美国西部的松树林面临着严重的火灾和侵蚀,通常与过去的灭火和土地使用有关.
- 历史上的树环数据表明,在欧美定居点之前,频繁的,轻度的火灾保持了开放的立场.
- 定居前的时代 (公元1500-1900年左右) 较冷,这引发了关于气候在最近灾难性火灾中的作用的问题.
研究的目的:
- 在xeric ponderosa松树林中重建Holocene火灾历史.
- 检查过去的火灾制度与气候变化之间的联系.
- 评估在气候变暖的情况下恢复定居前火灾过程的可行性.
主要方法:
- 在爱达荷州中部的岩风扇中,与火灾相关的沉积物沉积物的约会.
- 在xeric ponderosa松生态系统中分析Holocene火灾历史.
- 将火灾事件与古气候数据相关联.
主要成果:
- 较冷的气候时期与频繁的,低严重度的火灾有关,这可能是由底层树木的生长驱动的.
- 温暖的气候时期出现了严重的干旱,导致置火灾和大量的碎片流.
- 这些温暖时期的事件与黄石国家公园的亚高山森林中类似的事件一致.
结论:
- 气候对 ponderosa 松树林的火灾严重程度和频率有很大的影响.
- 过去的火灾制度与气候变化密切相关,温暖的时期促进了严重的火灾和侵蚀.
- 在未来更温暖的气候中,恢复定居前的火灾过程可能具有挑战性,这有利于激烈的野火.
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