Recent shifts in the occurrence, cause, and magnitude of animal mass mortality events
Recent shifts in the occurrence, cause, and magnitude of animal mass mortality events
复制标题
DOI：
10.1073/pnas.1414894112
复制
发表时间：
2015-01-27
影响因子：
11.1
通讯作者：
Carlson, Stephanie M.
中科院分区：
文献类型：
--
作者：
Fey, Samuel B.;Siepielski, Adam M.;Carlson, Stephanie M.
大规模死亡事件（MMEs）是迅速发生的灾难性人口统计事件，它打断了背景死亡率水平。单个MME的观测规模令人震惊：消除90%以上的人口，导致超过10亿人死亡，或在一次事件中产生7亿吨死亡生物质。尽管有大量关于个别MME的文献，但我们不了解MME发生和规模的主要特征，其原因或趋势。因此，在全球和区域对自然系统的持续扰动之后，没有一个框架可用于将中小微企业置于背景之中。在这里，我们对来自地球仪的727个已发表的MME进行了分析，影响了2，407个动物种群。我们发现，MMEs的幅度一直在加强鸟类，鱼类和海洋无脊椎动物;不变的哺乳动物;和减少爬行动物和两栖动物。当我们考虑到自1940年以来MME发生率的增加时，这些幅度的变化被证明是稳健的。然而，目前尚不清楚MME发生率的增加是否代表一种真实的模式或仅仅是一种感知的增加。无论如何，MME的增加似乎与疾病的出现，生物毒性和多种相互作用的压力源产生的事件的增加有关，但MME原因的时间趋势在不同的分类群之间存在差异，可能与检测能力增加有关。此外，具有最大幅度的MME是由多种压力源、饥饿和疾病引起的MME。这些结果推进了我们对罕见的人口过程及其与全球和区域自然系统扰动的关系的理解。
Mass mortality events (MMEs) are rapidly occurring catastrophic demographic events that punctuate background mortality levels. Individual MMEs are staggering in their observed magnitude: removing more than 90% of a population, resulting in the death of more than a billion individuals, or producing 700 million tons of dead biomass in a single event. Despite extensive documentation of individual MMEs, we have no understanding of the major features characterizing the occurrence and magnitude of MMEs, their causes, or trends through time. Thus, no framework exists for contextualizing MMEs in the wake of ongoing global and regional perturbations to natural systems. Here we present an analysis of 727 published MMEs from across the globe, affecting 2,407 animal populations. We show that the magnitude of MMEs has been intensifying for birds, fishes, and marine invertebrates; invariant for mammals; and decreasing for reptiles and amphibians. These shifts in magnitude proved robust when we accounted for an increase in the occurrence of MMEs since 1940. However, it remains unclear whether the increase in the occurrence of MMEs represents a true pattern or simply a perceived increase. Regardless, the increase in MMEs appears to be associated with a rise in disease emergence, biotoxicity, and events produced by multiple interacting stressors, yet temporal trends in MME causes varied among taxa and may be associated with increased detectability. In addition, MMEs with the largest magnitudes were those that resulted from multiple stressors, starvation, and disease. These results advance our understanding of rare demographic processes and their relationship to global and regional perturbations to natural systems.