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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.more » « less
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Abstract Background and AimsUnderstanding shifts in the demographic and functional composition of forests after major natural disturbances has become increasingly relevant given the accelerating rates of climate change and elevated frequency of natural disturbances. Although plant demographic strategies are often described across a slow–fast continuum, severe and frequent disturbance events influencing demographic processes may alter the demographic trade-offs and the functional composition of forests. We examined demographic trade-offs and the shifts in functional traits in a hurricane-disturbed forest using long-term data from the Luquillo Forest Dynamics Plot (LFPD) in Puerto Rico. MethodsWe analysed information on growth, survival, seed rain and seedling recruitment for 30 woody species in the LFDP. In addition, we compiled data on leaf, seed and wood functional traits that capture the main ecological strategies for plants. We used this information to identify the main axes of demographic variation for this forest community and evaluate shifts in community-weighted means for traits from 2000 to 2016. Key ResultsThe previously identified growth–survival trade-off was not observed. Instead, we identified a fecundity–growth trade-off and an axis representing seedling-to-adult survival. Both axes formed dimensions independent of resprouting ability. Also, changes in tree species composition during the post-hurricane period reflected a directional shift from seedling and tree communities dominated by acquisitive towards conservative leaf economics traits and large seed mass. Wood specific gravity, however, did not show significant directional changes over time. ConclusionsOur study demonstrates that tree demographic strategies coping with frequent storms and hurricane disturbances deviate from strategies typically observed in undisturbed forests, yet the shifts in functional composition still conform to the expected changes from acquisitive to conservative resource-uptake strategies expected over succession. In the face of increased rates of natural and anthropogenic disturbance in tropical regions, our results anticipate shifts in species demographic trade-offs and different functional dimensions.more » « less
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