Climate Change Effects on Interacting Disturbances in Forest Ecosystems

Drought, wildfire, wind, insects, and pathogens can interact across space and time to shape forest ecosystems. Although subdisciplines in ecology have long studied individual disturbances, their interactions remain poorly understood, particularly under climate change. Further, inconsistent terminology used to describe these interactions compounds this gap. To address this challenge, we first develop a unifying framework and then review the literature to synthesize climate change effects on the seven classes of forest disturbance interactions. Climate change alters the impacts of disturbance interactions by shifting (a) the characteristics of disturbances and (b) the effects of interactions when they occur. Many studies document amplifying effects of climate change, and disturbance interactions governed by nonlinearities and positive feedbacks can be particularly transformative in forest ecosystems. In some cases, however, climate change can dampen outcomes of disturbance interactions, which may buffer forests from disturbance impacts. Critically, climate change is expected to increase the frequency of ecosystem transitions worldwide by amplifying the outcomes of complex interactions, particularly coupled feedbacks and network effects. Although there is strong evidence that climate change is modifying some disturbance interactions, they remain an important, yet understudied frontier in ecology.