Herbivory by non-native species can create strong direct and indirect effects on plant and arthropods communities that can potentially cross ecosystem boundaries. Yet, the cross-ecosystems impacts of non-native species are poorly understood. We took advantage of ongoing invasions by non-native ungulates in Patagonia, Argentina, to examine their cross-ecosystem impacts on water parameters, littoral vegetation and aquatic macroinvertebrate assemblages in wetlands. We found a gradient of invasion by non-native ungulates from intact (non-invaded) to highly invaded wetlands. These highly invaded wetlands had ~ 24% less vegetation cover, which was 72% shorter in height than vegetation in intact wetlands. As a result, the abundance of predatory macroinvertebrates such as Odonata (dragonflies) was reduced by ~ 90%; while Diptera were ~ 170% more abundant, and Oligochaeta were recorded mostly at invaded sites. In contrast, we did not find evidence that non-native ungulates altered water parameters. Understanding the indirect consequences of invasive non-native species is crucial for quantifying the real impacts of global change. Our results show strong cross-ecosystem impacts of non-native ungulates on macroinvertebrate wetland communities, highlighting the importance of indirect interactions beyond ecosystem boundaries.

非本地物种的食草可以对植物和节肢动物群落产生强大的直接和间接影响，这有可能跨越生态系统的边界。然而，人们对非本地物种对生态系统的影响知之甚少。我们利用了阿根廷巴塔哥尼亚的非原生有蹄类动物不断入侵的优势，研究了它们的跨生态系统对湿地中水参数，沿海植被和水生大型无脊椎动物种群的影响。我们发现非原生有蹄类动物从完整（未入侵）到高度入侵的湿地的入侵梯度。这些高度入侵的湿地的植被覆盖度减少了约24％，比完整湿地的植被高度缩短了72％。结果，捕食性大型无脊椎动物，如Odonata（蜻蜓）的丰度降低了约90％。而Diptera的丰富度约为170％，和Oligochaeta大多记录在入侵地点。相比之下，我们没有找到非原生有蹄类动物改变水参数的证据。了解外来入侵物种的间接后果对于量化全球变化的实际影响至关重要。我们的结果表明，非原生有蹄类动物对大型无脊椎动物湿地社区具有强大的跨生态系统影响，突显了生态系统边界以外的间接相互作用的重要性。