作者：Paquette, C., Di Girolamo, D., Pham, J.  et al.

Climate change is reshaping freshwater ecosystems worldwide, yet the extent to which its effects differ across trophic levels remains poorly understood. Despite growing evidence of community restructuring, few studies have jointly examined how multiple trophic levels respond to climate forcing within a functional and network-based framework. Herein, we assessed how fish and zooplankton communities respond to contemporary and projected end-of-century climate conditions using different shared socioeconomic pathways (SSP1-2.6, SSP3-7.0, and SSP5-8.5). By means of joint species distribution models and ecological network analyses, we examined fish-zooplankton co-responses to environmental gradients, quantified trait-environment relationships, and evaluated potential species interactions. We found that fish and zooplankton displayed distinct community and functional responses to current and projected climate gradients. Although both trophic levels were primarily influenced by climatic variables, fish exhibited stronger trait-climate relationships, including declining body size and increasing thermal tolerance with warming. Through ecological network analyses, we then demonstrated that freshwater communities tended to become more homogenized by 2100 under future climate change. Together, these results suggest contrasting climate sensitivities across trophic levels, potentially leading to trophic decoupling and functional reorganization of freshwater food webs at the regional scale. Our study highlights the value of combining trait-based and network approaches to better anticipate community-level responses to climate change.

气候变化正在重塑全球淡水生态系统，但其影响在不同营养级之间的差异程度仍知之甚少。尽管关于群落结构重组的证据日益增多，但在功能与网络框架下联合考察多个营养级如何响应气候胁迫的研究仍然很少。研究基于不同的共享社会经济路径情景（SSP1-2.6、SSP3-7.0 和 SSP5-8.5），评估了鱼类与浮游动物群落对当前及世纪末预估气候条件的响应。借助联合物种分布模型（JSDM）与生态网络分析，考察了鱼—浮游动物对环境梯度的协同响应，量化了性状—环境关系，并评估了潜在的物种间相互作用。研究发现，鱼类与浮游动物对当前及预估气候梯度表现出明显不同的群落与功能响应。尽管两个营养级均主要受气候变量影响，但鱼类的性状—气候关系更强，具体表现为随变暖体型减小、热耐受性提高。通过生态网络分析，我们进一步表明，在未来气候变化下，淡水群落到2100年趋于更加同质化。综合来看，这些结果提示不同营养级对气候的敏感性存在差异，可能在区域尺度上导致营养级脱耦与淡水食物网的功能重组。研究凸显了性状分析与网络方法相结合对于更好预判群落水平气候响应的价值。

（来源：Global Change Biology 2026 Issue 4  DOI: 10.1111/gcb.70845）