It is clear that ecosystems are devastated after a volcanic eruption coats the landscape with a layer of ash; however, the ecological recovery of mammalian communities after eruptions is poorly understood. Volcanic eruptions vary with magnitude and type and only a fraction of them have been analysed for effects on mammalian communities. To better understand mammalian community recovery, I investigated how species richness, evenness, and similarity change across volcanic boundaries in the 1980 Mount Saint Helens (MSH), Washington, and 1914–1917 Mount Lassen, California, eruptions. I compared these eruptions to Mount Rainier, Washington and Mount Shasta, California as controls for regional changes in the fauna. Richness and evenness remain relatively unchanged in Lassen. MSH saw an immediate drop in richness, followed by an increase over 5 years to pre-eruptive levels. Chord distance analysis suggests no long-term change in the Lassen fauna. The pre- and post-MSH fauna are different from one another. The post-eruptive fauna was more similar to neighbouring regions. It is clear from my results that larger eruptions tend to have a greater impact on mammalian community recovery than smaller eruptions, but ultimately, mammalian populations are robust and the presence of neighbouring communities is important for recolonizing devastated areas.

中文翻译：

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哺乳动物社区对历史性火山爆发的反应

很明显，在火山喷发后，生态系统被摧毁了一层灰烬。然而，人们对火山爆发后哺乳动物群落的生态恢复知之甚少。火山喷发因规模和类型而异，仅分析了其中一小部分对哺乳动物群落的影响。为了更好地了解哺乳动物群落的恢复，我调查了 1980 年华盛顿圣海伦山 (MSH) 和 1914-1917 年加利福尼亚州拉森火山喷发中物种丰富度、均匀度和相似性跨越火山边界的变化。我将这些火山喷发与华盛顿州雷尼尔山和加利福尼亚州沙斯塔山进行了比较，作为动物群区域变化的对照。拉森的丰富度和均匀度保持相对不变。MSH 的丰富度立即下降，然后在 5 年内增加到喷发前的水平。弦距离分析表明拉森动物群没有长期变化。MSH 之前和之后的动物群彼此不同。喷发后的动物群与邻近地区更相似。从我的结果中可以清楚地看出，较大的火山喷发往往比较小的火山喷发对哺乳动物群落的恢复产生更大的影响，但最终，哺乳动物种群是强大的，相邻群落的存在对于重新殖民受灾地区很重要。