摘要
Aquatic ecosystems are tightly linked to terrestrial ecosystems by exchanges of resources, which influence species interactions, community dynamics and functioning in both ecosystem types. However, our understanding of how this coupling responds to climate warming is restricted to temperate, boreal and arctic regions, with limited knowledge from tropical ecosystems. We investigated how warming aquatic ecosystems impact cross-ecosystem exchanges in the tropics, through the export of aquatic resources into the terrestrial environment and the breakdown of terrestrial resources within the aquatic environment. We experimentally heated 50 naturally assembled aquatic communities, contained within different-sized tank-bromeliads, to a 23.5–32°C gradient of mean water temperatures. The biomass, abundance and richness of aquatic insects emerging into the terrestrial environment all declined with rising temperatures over a 45-day experiment. Structural equation and linear mixed effects modelling suggested that these impacts were driven by deleterious effects of warming on insect development and survival, rather than being mediated by aquatic predation, nutrient availability or reduced body size. Decomposition was primarily driven by microbial activity. However, total decomposition by both microbes and macroinvertebrates increased with temperature in all but the largest ecosystems, where it decreased. Thus, warming decoupled aquatic and terrestrial ecosystems, by reducing the flux of aquatic resources to terrestrial ecosystems but variably enhancing or reducing terrestrial resource breakdown in aquatic ecosystems. In contrast with increased emergence observed in warmed temperate ecosystems, future climate change is likely to reduce connectivity between tropical terrestrial and aquatic habitats, potentially impacting consumers in both ecosystem types. As tropical ectotherms live closer to their thermal tolerance limits compared to temperate species, warming can disrupt cross-ecosystem dynamics in an interconnected tropical landscape and should be considered when investigating ecosystem-level consequences of climate change.
摘要译文
水生生态系统通过资源交换与地面生态系统紧密相关，影响物种相互作用，社区动态和在两种生态系统类型中的运作。然而，我们了解该耦合如何应对气候变暖的响应被限制为温带，北极和北极地区，具有来自热带生态系统的知识有限。我们调查了温暖的水生生态系统如何影响热带地区的交叉生态系统交流，通过出口水生进入地面环境以及水生环境中的陆地资源分解。我们通过实验在不同尺寸的坦克 - 溴eliads内加热50个天然组装的水生群落，达到23.5-32°C的平均水温梯度。水生昆虫的生物质，丰富和丰富性涌入陆地环境，均涉及45天的温度升高。结构方程和线性混合效果建模表明，这些影响是通过对昆虫发育和生存的热化影响而导致的，而不是通过水生捕食，营养可用性或体积减少介导。分解主要由微生物活性驱动。然而，Microbes和Macroinvertebrets的总分解随着最大的生态系统的温度而增加，它减少了最大的生态系统。因此，通过减少水生资源的助焊对地面生态系统的助焊剂来变暖的水生和陆地生态系统，而是可变地增强或减少水生生态系统中的陆地资源崩溃。相反，随着温暖的温带生态系统中观察到的增加，未来的气候变化可能会降低热带陆地和水生栖息地之间的连通性，可能影响两种生态系统类型的消费者。随着热带异位与温带物种相比更接近其热耐受限制，温暖可以破坏互连的热带景观中的交叉生态系统动态，并在调查气候变化的生态系统级后果时应考虑。
Liam N. Nash[1];Pablo A. P. Antiqueira[2];Gustavo Q. Romero[2];Paula M. de Omena[3];Pavel Kratina[1]. Warming of aquatic ecosystems disrupts aquatic–terrestrial linkages in the tropics[J]. Journal of Animal Ecology, 2021,90(7): 1623-1634