Limits to reproduction and seed size-number trade-offs that shape forest dominance and future recovery

Abstract

The relationships that control seed production in trees are fundamental to understanding the evolution of forest species and their capacity to recover from increasing losses to drought, fire, and harvest. A synthesis of fecundity data from 714 species worldwide allowed us to examine hypotheses that are central to quantifying reproduction, a foundation for assessing fitness in forest trees. Four major findings emerged. First, seed production is not constrained by a strict trade-off between seed size and numbers. Instead, seed numbers vary over ten orders of magnitude, with species that invest in large seeds producing more seeds than expected from the 1:1 trade-off. Second, gymnosperms have lower seed production than angiosperms, potentially due to their extra investments in protective woody cones. Third, nutrient-demanding species, indicated by high foliar phosphorus concentrations, have low seed production. Finally, sensitivity of individual species to soil fertility varies widely, limiting the response of community seed production to fertility gradients. In combination, these findings can inform models of forest response that need to incorporate reproductive potential.

Ecological Vulnerability in the Red Soil Erosion Area of Changting under Continuous Ecological Restoration: Spatiotemporal Dynamic Evolution and Prediction

“…It is one of southern China's red soil erosion zone's most typical water and soil loss areas. Soil restoration of degraded agricultural land [24], forest regeneration [25], the spatial distribution of forest aboveground biomass, and reasonable tree density [26] are of great significance to the control of water and soil loss and the protection and restoration of ecosystem functions in the red soil erosion area of Changting. Therefore, in our evaluation index system, soil erosion intensity, normalized difference vegetation index, and landscape diversity were selected to reflect the water and soil loss, spatial forest distribution, forest density, the number of landscape elements, and the proportion of each landscape element in the study area.…”

Mechanisms driving interspecific variation in regional synchrony of trees reproduction

“…The variation in the timing of the signal lacked a clear climatic pattern. Perhaps site characteristics, such as soil conditions, density or stand age, that affect reproductive investment (Journé et al, 2022; Pesendorfer et al, 2020; Qiu et al, 2022), would help to structure the variation in the timing of strongest weather cues among populations. We now know that spatiotemporal variation in weather cueing exists, and its extent is species‐specific and ecologically important, which opens new venues for future research.…”

Effects of biotic interactions on plant fecundity depend on spatial and functional structure of communities and time since disturbance

“…Functional traits, as proposed by Violle et al (2007), are traits that indirectly affect the fitness of a plant and underlie performance traits which directly measure different fitness components (growth, survival and reproduction). Functional traits of neighbours, therefore, describe species' life histories and rates of resource acquisition (Adler et al, 2014; Collins et al, 2016; Qiu et al, 2022; Rüger et al, 2018; Wright et al, 2004), as well as the resources they provide for mutual pollinators and seed predators (Gardarin et al, 2018; Lavorel et al, 2013). Hence, functional traits are also related to competition for resources and animal‐mediated interactions between plants (Funk & Wolf, 2016; Kraft et al, 2015; Kunstler et al, 2016; Morales‐Castilla et al, 2015; Nottebrock, Schmid, Mayer, et al, 2017; Nottebrock, Schmid, Treurnicht, et al, 2017).…”