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Summary Rapid changes in climate and disturbance regimes, including droughts and hurricanes, are likely to influence tropical forests, but our understanding of the compound effects of disturbances on forest ecosystems is extremely limited. Filling this knowledge gap is necessary to elucidate the future of these ecosystems under a changing climate.We examined the relationship between hurricane response (damage, mortality, and resilience) and four hydraulic traits of 13 dominant woody species in a wet tropical forest subject to periodic hurricanes.Species with high resistance to embolisms (lowP50values) and higher safety margins () were more resistant to immediate hurricane mortality and breakage, whereas species with higher hurricane resilience (rapid post‐hurricane growth) had high capacitance andP50values and low . During 26 yr of post‐hurricane recovery, we found a decrease in community‐weighted mean values for traits associated with greater drought resistance (leaf turgor loss point,P50, ) and an increase in capacitance, which has been linked with lower drought resistance.Hurricane damage favors slow‐growing, drought‐tolerant species, whereas post‐hurricane high resource conditions favor acquisitive, fast‐growing but drought‐vulnerable species, increasing forest productivity at the expense of drought tolerance and leading to higher overall forest vulnerability to drought.
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Tree height and leaf drought tolerance traits shape growth responses across droughts in a temperate broadleaf forest
Summary As climate change drives increased drought in many forested regions, mechanistic understanding of the factors conferring drought tolerance in trees is increasingly important. The dendrochronological record provides a window through which we can understand how tree size and traits shape growth responses to droughts.We analyzed tree‐ring records for 12 species in a broadleaf deciduous forest in Virginia (USA) to test hypotheses for how tree height, microenvironment characteristics, and species’ traits shaped drought responses across the three strongest regional droughts over a 60‐yr period.Drought tolerance (resistance, recovery, and resilience) decreased with tree height, which was strongly correlated with exposure to higher solar radiation and evaporative demand. The potentially greater rooting volume of larger trees did not confer a resistance advantage, but marginally increased recovery and resilience, in sites with low topographic wetness index. Drought tolerance was greater among species whose leaves lost turgor (wilted) at more negative water potentials and experienced less shrinkage upon desiccation.The tree‐ring record reveals that tree height and leaf drought tolerance traits influenced growth responses during and after significant droughts in the meteorological record. As climate change‐induced droughts intensify, tall trees with drought‐sensitive leaves will be most vulnerable to immediate and longer‐term growth reductions.
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- PAR ID:
- 10451020
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 231
- Issue:
- 2
- ISSN:
- 0028-646X
- Format(s):
- Medium: X Size: p. 601-616
- Size(s):
- p. 601-616
- Sponsoring Org:
- National Science Foundation
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