Extreme heat changes post-heat wave community reassembly
Extreme heat changes post-heat wave community reassembly
复制标题
热浪后的极端高温变化社区重组
DOI：
10.1002/ece3.1490
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发表时间：
2015
影响因子：
2.6
通讯作者：
Weithoff
中科院分区：
文献类型：
--
作者：
Seifert;Weithoff
气候预报预测极端高温事件将进一步增加。这些对生物多样性构成威胁，因为它们促使种群减少和当地物种灭绝。这意味着生态社区将需要更强烈地依赖恢复过程，例如从Meta社区环境中恢复。人们对极端事件强度的差异如何改变随后群落重组的结果以及这些极端事件是否以阻止消失物种成功重建的方式改变生物环境知之甚少。我们研究了由藻类和草食性轮虫组成的复制水生群落，该设计涉及控制和两种不同的热浪强度处理（29°C和39°C）。随后在两种处理中的每一种中，以相同的时间和密度重新引入遭受热诱导灭绝的动物物种。39°C的处理导致所有重复中的群落关闭，这意味着先前成功的食草动物物种无法在加热后的波群落中重新建立自己。相比之下，在29°C事件之后从未发生过这种闭合。热浪强度决定了食草动物的数量，并强烈影响藻类的相对丰度。因此，重新引入的食草动物物种面临着显著不同的食物环境。热浪强度产生的这种生态遗产导致了食草动物物种重新引入的失败或成功的差异。在极端热浪之后，重组的变化更大，因此更难预测，而在温和的热浪之后，重组的变化更大。我们的研究结果适用于相对简单的社区，但它们表明，极端高温事件带来的生态遗产可能会改变随后的生态恢复，甚至阻止丢失物种的成功重建。了解促进和阻止生态恢复的过程对于物种重新引入计划的成功以及我们恢复被极端环境破坏的生态系统的能力至关重要。
Climate forecasts project further increases in extremely high‐temperature events. These present threats to biodiversity, as they promote population declines and local species extinctions. This implies that ecological communities will need to rely more strongly on recovery processes, such as recolonization from a meta‐community context. It is poorly understood how differences in extreme event intensity change the outcome of subsequent community reassembly and if such extremes modify the biotic environment in ways that would prevent the successful re‐establishment of lost species. We studied replicated aquatic communities consisting of algae and herbivorous rotifers in a design that involved a control and two different heat wave intensity treatments (29°C and 39°C). Animal species that suffered heat‐induced extinction were subsequently re‐introduced at the same time and density, in each of the two treatments. The 39°C treatment led to community closure in all replicates, meaning that a previously successful herbivore species could not re‐establish itself in the postheat wave community. In contrast, such closure never occurred after a 29°C event. Heat wave intensity determined the number of herbivore extinctions and strongly affected algal relative abundances. Re‐introduced herbivore species were thus confronted with significantly different food environments. This ecological legacy generated by heat wave intensity led to differences in the failure or success of herbivore species re‐introductions. Reassembly was significantly more variable, and hence less predictable, after an extreme heat wave, and was more canalized after a moderate one. Our results pertain to relatively simple communities, but they suggest that ecological legacies introduced by extremely high‐temperature events may change subsequent ecological recovery and even prevent the successful re‐establishment of lost species. Knowing the processes promoting and preventing ecological recovery is crucial to the success of species re‐introduction programs and to our ability to restore ecosystems damaged by environmental extremes.