Climate Change Biology Research Group, State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, No 2, Yuanmingyuan West Road, Haidian District, Beijing, 100193, China.
Glob Chang Biol. 2015 May;21(5):1794-808. doi: 10.1111/gcb.12654. Epub 2014 Aug 4.
The frequency and magnitude of extreme events are predicted to increase under future climate change. Despite recent advancements, we still lack a detailed understanding of how changes in the frequency and amplitude of extreme climate events are linked to the temporal and spatial structure of natural communities. To answer this question, we used a combination of laboratory experiments, field experiments, and analysis of multi-year field observations to reveal the effects of extreme high temperature events on the demographic rates and relative dominance of three co-occurrence aphid species which differ in their transmission efficiency of different agricultural pathogens. We then linked the geographical shift in their relative dominance to frequent extreme high temperatures through a meta-analysis. We found that both frequency and amplitude of extreme high temperatures altered demographic rates of species. However, these effects were species-specific. Increasing the frequency and amplitude of extreme temperature events altered which species had the highest fitness. Importantly, this change in relative fitness of species was consistent with significant changes in the relative dominance of species in natural communities in a 1 year long field heating experiment and 6 year long field survey of natural populations. Finally, at a global spatial scale, we found the same relationship between relative abundance of species and frequency of extreme temperatures. Together, our results indicate that changes in frequency and amplitude of extreme high temperatures can alter the temporal and spatial structure of natural communities, and that these changes are driven by asymmetric effects of high temperatures on the demographic rates and fitness of species. They also highlight the importance of understanding how extreme events affect the life-history of species for predicting the impacts of climate change at the individual and community level, and emphasize the importance of using a broad range of approaches when studying climate change.
未来气候变化预计会增加极端事件的频率和强度。尽管最近取得了一些进展，但我们仍然缺乏对极端气候事件的频率和幅度变化如何与自然群落的时间和空间结构联系起来的详细了解。为了回答这个问题，我们结合实验室实验、野外实验和多年野外观测分析，揭示了极端高温事件对三种共存蚜虫物种的种群动态速率和相对优势的影响，这三种蚜虫在传播不同农业病原体方面的效率不同。然后，我们通过荟萃分析将它们相对优势的地理分布与频繁的极端高温联系起来。我们发现，极端高温的频率和幅度都改变了物种的种群动态速率。然而，这些影响是物种特异性的。增加极端温度事件的频率和幅度改变了哪些物种具有最高的适应性。重要的是，这种物种相对适应性的变化与自然群落中物种相对优势的显著变化一致，这种变化是在长达 1 年的野外加热实验和长达 6 年的自然种群野外调查中观察到的。最后，在全球空间尺度上，我们发现物种相对丰度与极端温度频率之间存在相同的关系。总之，我们的研究结果表明，极端高温的频率和幅度的变化可以改变自然群落的时间和空间结构，而这种变化是由高温对物种种群动态速率和适应性的不对称影响驱动的。它们还强调了了解极端事件如何影响物种的生活史对于预测气候变化对个体和群落层面的影响的重要性，并强调在研究气候变化时使用广泛的方法的重要性。
