Ecological communities face a variety of environmental and anthropogenic stressors acting simultaneously. Stressor impacts can combine additively or can interact, causing synergistic or antagonistic effects. Our knowledge of when and how interactions arise is limited, as most models and experiments only consider the effect of a small number of non-interacting stressors at one or few scales of ecological organization. This is concerning because it could lead to significant underestimations or overestimations of threats to biodiversity. Furthermore, stressors have been largely classified by their source rather than by the mechanisms and ecological scales at which they act (the target). Here, we argue, first, that a more nuanced classification of stressors by target and ecological scale can generate valuable new insights and hypotheses about stressor interactions. Second, that the predictability of multiple stressor effects, and consistent patterns in their impacts, can be evaluated by examining the distribution of stressor effects across targets and ecological scales. Third, that a variety of existing mechanistic and statistical modelling tools can play an important role in our framework and advance multiple stressor research.

生态群落面临着同时作用的各种环境和人为压力源。压力源的影响可以叠加或相互作用，导致协同或对抗效应。我们对相互作用何时以及如何发生的了解是有限的，因为大多数模型和实验只考虑少数非相互作用压力源在一个或几个生态组织尺度上的影响。这令人担忧，因为它可能导致对生物多样性威胁的严重低估或高估。此外，压力源在很大程度上是根据其来源分类的，而不是根据它们作用的机制和生态规模（目标）。在这里，我们首先争辩说，按目标和生态规模对压力源进行更细致的分类可以产生关于压力源相互作用的有价值的新见解和假设。其次，可以通过检查压力源效应在目标和生态尺度上的分布来评估多重压力源效应的可预测性及其影响的一致模式。第三，各种现有的机械和统计建模工具可以在我们的框架中发挥重要作用，并推进多重压力源研究。