Madrigal-Gonzalez, J. | Search bioRxiv

bioRxiv2025

Indirect interactions driven by soil effects enable coexistence among competing plant species

Reciprocal effects between plants and soil have been proposed as mechanisms that promote coexistence. However, recent theoretical and empirical works have questioned their role in stabilizing coexistence within multispecies communities. In these systems, indirect interactions mediated by plant-soil feedback may play a pivotal but often overlooked role. We investigate these indirect interactions using an experimental system of two competing shrub species grown in soil conditioned by a third tree species. Tree-induced shifts in soil microbial communities, metabolites, and nutrients boost growth in the weak competitor species while reducing germination in the dominant competitor. Simulations demonstrate that these shifts in plant performance are sufficient to stabilize coexistence and to closely reproduce natural spatial distribution patterns. Our findings underscore the role of plant-soil feedback in driving indirect interactions that sustain coexistence in diverse plant communities, highlighting the importance of indirect but also positive and negative multitrophic interactions in maintaining biodiversity.

ecology↗

bioRxiv2023

Forest structural diversity determines tree growth synchrony in response to climate change

After centuries of deforestation, many industrialised countries are experiencing an increase in forest area and biomass due to changes in land- and forest-use since the mid-20th century. At the same time, the impacts of climate change on forests are aggravating, but the interplay between past land- and forest-use (i.e. land- and forest-use legacies) and climate change in forest functioning remains elusive. Here using network theory and linear mixed models, we quantified how land- and forest-use legacies modulate tree growth synchrony in response to climate change. We analysed tree growth data from European beech (Fagus sylvatica L.) stands with different histories of forest management at the species rear edge. We found that tree growth synchrony increased following heatwaves, late spring frosts, and reduced precipitation. Interestingly, the greatest tree growth synchrony occurred in recently-established forests, while stands containing large trees and heterogeneous tree sizes showed much lower growth synchrony. Our results highlight the importance of maintaining large trees and structurally heterogeneous forests to mitigate the negative effects of climate change on forest productivity, and thereby, increase forest resilience to future forest climate risks.

ecology↗