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维持东方树林:火灾和地形对植被和燃料的协同效应
Todd F Hutchinson1, Bryce T Adams1, Matthew B Dickinson1
1Northern Research Station, US Forest Service, Delaware, Ohio, USA.
概括
在美国东部的树林中,在过去的20年里,规定的火灾和机械稀释逆转了森林中化. 处理促进了树的再生和地面层的多样性,但增加了大型木质燃料,可能会增加野火风险.
科学领域:
- 森林生态森林生态学
- 火灾生态学 火灾生态学
- 保护生物学 保护生物学
背景情况:
- 美国东部的树森林面临着因增加的耐阴影物种而导致的化,抑制了树的再生.
- 从历史上看,人为的火灾促进了树的主导地位; 现在使用规定的火来逆转 mesophication.
研究的目的:
- 评估对美国东部树林的约20年的规定火灾 (Fire),机械部分收获 (Mech) 和联合处理 (Mech + Fire) 的影响.
- 评估处理对介质植物竞争者的影响,木再生,地面层植物和燃料床.
- 检查处理和地形对森林结构和燃料的交互影响.
主要方法:
- 在2000年建立了俄俄山火灾和火灾替代品 (FFS) 研究,使用了火灾,机械和机械+火灾治疗.
- 监测了大约20年的植被结构,树木再生,地面层多样性和燃料负载.
- 分析了对地形湿度和能量梯度的处理效应.
主要成果:
- 火和Mech + 火处理逆转了美索菲化;只有Mech没有.
- 火灾减少了中生植物树密度,增加了大树和树的再生,特别是在干燥/中间地点.
- 火灾促进了地面层的多样性,但增加了大型木质燃料,可能会在干旱期间增加野火风险.
- 处理效应由地形调节,在干燥的地点增加火灾严重性.
结论:
- 二十年的重复火灾,有或没有机械稀释,显著改变了森林轨迹,在大多数地点逆转了中层化.
- 定期的火灾制度可以维持东部树林并增强植物多样性,但影响受到地形的影响.
- 增加的大型木质燃料需要谨慎管理,以减轻潜在的高严重性野火风险.
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