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Life‐history strategies emerge from eco‐evolutionary constraints, where organisms allocate limited resources to growth, survival, and reproduction, resulting in trade‐offs such as the growth–survival trade‐off. There is still a limited understanding of whether and how disturbance regimes and successional stages might mediate such trade‐offs, with potential consequences for species population dynamics and community assembly. Here, we investigate how disturbances shape the growth–survival trade‐off by comparing early and late‐successional forest stands across the eastern United States. Using large‐scale sampling to capture the realised niche of 68 temperate species, we estimated species‐specific mortality probabilities under zero growth (a proxy for resource‐poor environments) applying a Bayesian multilevel modelling framework. We tested trade‐offs between these estimates and species' maximum growth capacity (a proxy for resource‐rich environments), within and across early and late‐successional stands. Overall, we found a weak growth–survival trade‐off among temperate tree species. No clear evidence of this trade‐off was found in early successional stands , while late‐successional stands showed a relatively stronger—though still weak—positive association between species' maximum growth and mortality under zero growth conditions. Disturbances therefore seem to mediate a filtering of tree life‐history strategies. Consequently, an increase in disturbance rates or changes in their regime could disrupt the growth–survival trade‐off in temperate forests. Life‐history strategies arise from eco‐evolutionary constraints and can lead to trade‐offs like tree growth and survival. While temperate tree species in late‐successional or low‐disturbance‐frequency forests do show a growth–survival trade‐off, this trade‐off is weak and was not found in early successional or high‐disturbance‐frequency stands, nor across all stages combined. Our findings highlight a role of disturbances in filtering life‐history strategies and their potential impact on forest dynamics and global carbon cycling but also a need to better understand the mediating processes of tree demographic trade‐offs.
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The pace of life for forest trees
Tree growth and longevity trade-offs fundamentally shape the terrestrial carbon balance. Yet, we lack a unified understanding of how such trade-offs vary across the world’s forests. By mapping life history traits for a wide range of species across the Americas, we reveal considerable variation in life expectancies from 10 centimeters in diameter (ranging from 1.3 to 3195 years) and show that the pace of life for trees can be accurately classified into four demographic functional types. We found emergent patterns in the strength of trade-offs between growth and longevity across a temperature gradient. Furthermore, we show that the diversity of life history traits varies predictably across forest biomes, giving rise to a positive relationship between trait diversity and productivity. Our pan-latitudinal assessment provides new insights into the demographic mechanisms that govern the carbon turnover rate across forest biomes.
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- Award ID(s):
- 2020424
- PAR ID:
- 10567628
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Science
- Date Published:
- Journal Name:
- Science
- Volume:
- 386
- Issue:
- 6717
- ISSN:
- 0036-8075
- Page Range / eLocation ID:
- 92 to 98
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1126/science.adk9616
