Fire, Flood, and Fury – Forest Ecophysiological Response to Extreme Events

Heat waves, droughts, wind, ice-storms, fires, flooding, and insect or pathogen outbreaks can have dramatic impacts on tree and forest ecosystem function, and the frequency of such events are projected to increase in the future. These abrupt disturbance events can cause damage to hydraulic pathways, phloem or cambial tissues, roots and photosynthetic performance, or induce premature branch or leaf loss without retranslocation of nutrients. All these forms of damage can have profound impacts on plant carbon balance, carbon partitioning, nutrient status and soil biogeochemical cycling that can continue long after the extreme event ends. Extreme disturbance events can even lead to complete loss of a plant population, resulting in dramatic shifts in ecosystem composition and, potentially, function. While above and belowground trait assemblages have adapted to localized periodic stressors, extreme events may intensify selection pressures on traits related to plant growth and survival. Variation in plant physiological traits implies differential damage thresholds to external drivers which, if known, could be used to predict ecosystem response to future events. However, we have little knowledge of the physiological mechanisms underlying forest response to extreme events in their environment. Consequently, current state-of-the-art models perform poorly in simulating ecological impacts of extreme events, as they either neglect or over-simplify these impacts, leading to poor projections of ecosystem function both during and after the event. Assessing the impact of extreme events on forest ecophysiology thus poses a major challenge to the community because of the very nature of such events: they are often unanticipated, and their effects can be out of proportion to the duration of the stress. Here, we bring together a collection of exciting ecophysiological research on extreme events, to both promote visibility of this growing problem, and to facilitate improved understanding of both chronic and acute stress in forest ecosystems.

We invite manuscripts that address topics related to Forest Ecophysiological Response to Extreme Events based on vigorous, objective observational studies, well-designed experiments or manipulations, meta-analyses, reviews or modeling exercises. We especially hope to attract manuscripts that test hypotheses and describe results through novel insights into ecophysiological processes, or new modeling frameworks.