Experimental heatwaves and warming cause distinctive community responses through their interactions with a novel species
Experimental heatwaves and warming cause distinctive community responses through their interactions with a novel species
复制标题
DOI：
10.1101/2023.03.24.534073
复制
发表时间：
2023-03
期刊：
影响因子：
--
通讯作者：
Jinlin Chen;O. Lewis
中科院分区：
文献类型：
--
作者：
Jinlin Chen;O. Lewis
随着平均气温的升高和热浪的频繁发生，物种正在扩大它们的分布范围，以殖民新的栖息地。由此产生的新的物种相互作用将同时塑造温度驱动的居民社区重组。气候变化和气候变化促进的入侵的相互作用影响很少在多营养群落中进行研究，并且可能因气候驱动因素的性质（即极端气候或持续变暖）而有所不同。我们在实验室条件下重建了一个典型的高海拔热带雨林网站在澳大利亚昆士兰州，包括四个果蝇种和两个相关的寄生蜂群落。我们使这些社区遭受热浪或持续变暖形式的气候变化，并结合涉及来自低海拔栖息地的新型宿主物种的入侵处理。这两种寄生虫物种都很敏感的变暖和热浪，而果蝇物种的人口反应是高度特异性的，反映了热耐受性，寄生，竞争和促进的综合影响。经过多代，热浪（但不是持续变暖）促进了低海拔物种在高地社区的建立。这种入侵物种的引入与其中一种寄生虫的丰度呈负相关，从而对其宿主及其竞争对手产生级联效应。因此，我们的研究揭示了极端温度和持续变暖对群落组成的不同影响，有时甚至是对比。它还强调了在一个双营养群落网络中，扩大范围的物种如何进一步改变气候影响的规模和方向。
As mean temperatures increase and heatwaves become more frequent, species are expanding their distributions to colonise new habitats. The resulting novel species interactions will simultaneously shape the temperature-driven reorganization of resident communities. The interactive effects of climate change and climate change-facilitated invasion have rarely been studied in multi-trophic communities, and are likely to differ depending on the nature of the climatic driver (i.e. climate extremes or constant warming). We recreated under laboratory conditions a host-parasitoid community typical of high-elevation rainforest sites in Queensland, Australia, comprising four Drosophila species and two associated parasitoid species. We subjected these communities to climate change in the form of either heatwaves or constant warming, in combination with an invasion treatment involving a novel host species from lower-elevation habitats. The two parasitoid species were sensitive to both warming and heatwaves, while the demographic responses of Drosophila species were highly idiosyncratic, reflecting the combined effects of thermal tolerance, parasitism, competition, and facilitation. After multiple generations, heatwaves (but not constant warming) promoted the establishment of low-elevation species in upland communities. The introduction of this invading species correlated negatively with the abundance of one of the parasitoid species, leading to cascading effects on its hosts and their competitors. Our study, therefore, reveals differing, sometimes contrasting, impacts of extreme temperatures and constant warming on community composition. It also highlights how the scale and direction of climate impacts could be further modified by range-expanding species within a bi-trophic community network.