What drives European beech (Fagus sylvatica L.) mortality after forest fires of varying severity?

Abstract

Predicting the timing and the amount of tree mortality after a forest fire is of paramount importance for forest management decisions related to post-fire measures. Such knowledge is particularly needed in mountainous regions where forest stands often serve as protection against natural hazards. In this paper, we focus on drivers and temporal trends in mortality processes of fire-injured beeches (Fagus sylvatica L.). We studied beech forests in the Southern European Alps, which burnt between 1970 and 2012. The results show that beech trees-which obviously lack fire-resistance traits-experience increased mortality within the first two decades post-fire after fires of moderate and high burn severity. Beech mortality was ubiquitous in high severity sites, whereas taller beeches had a higher survivability after fires of moderate severity, representing a crucial ecological legacy for natural beech regeneration. In contrast, mortality remains low and at a level similar to unburnt beech forests for low burn severity sites. Among mortality drivers, fungal infestation and the presence of fungal sporulation in particular was found to be most significant. Interestingly, fungi initiating post-fire tree mortality appeared to differ from fungi occurring after mechanical injury. From a practical point of view, insight gained regarding post-fire mortality is of great help in planning post-fire silvicultural measures. We confirm that this work is original and has not been published elsewhere, nor is it currently under consideration for publication elsewhere. The article has been read and approved by all authors.In this paper, we report on the timing and drivers of beech mortality after forest fires of varying severity. This is of importance with regards to forest management decisions related to post-fire measures. Such knowledge is particularly needed in mountainous regions where forest stands often serve as protection against natural hazards.We believe this topic is appropriate for publication by Forest Ecology and Management because it links fire-ecological processes with forest management decisions, and makes further contributions to a broader understanding of beech fire ecology. A parallel study focusing on post-fire regeneration processes after a mast year has recently been published in the journal of Forest Ecology and Management (doi:10.1016/j.foreco.2015.05.031).We have no conflicts of interest to disclose. If you find that the manuscript is appropriate for your journal, we suggest the following reviewers: Predicting the timing and the amount of tree mortality after a forest fire is of 22 paramount importance for forest management decisions related to post-fire measures. 23Such knowledge is particularly needed in mountainous regions where forest stands 24 often serve as protection against natural hazards. In this paper, we focus on drivers 25 and temporal trends in mortality processes of fire-injured beeches (Fagus sylvatica 26 L.). We studied beech forests in the Southern European Alps, which burnt between 27 ...

Aridity and competition drive fire resistance trait covariation in mountain trees

“…, Maringer et al. ). These correlative observations in mountain forests suggest that both BT and CBR reflect a strategy to resist fire by heat tolerance and flame avoidance, respectively, whereas TH relative to diameter (stem elongation) reflects a strategy to compete for light.…”

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