Do trade‐offs govern plant species’ responses to different global change treatments?

Abstract

Plants are subject to trade‐offs among growth strategies such that adaptations for optimal growth in one condition can preclude optimal growth in another. Thus, we predicted that a plant species that responds positively to one global change treatment would be less likely than average to respond positively to another treatment, particularly for pairs of treatments that favor distinct traits. We examined plant species’ abundances in 39 global change experiments manipulating two or more of the following: CO2, nitrogen, phosphorus, water, temperature, or disturbance. Overall, the directional response of a species to one treatment was 13% more likely than expected to oppose its response to a another single‐factor treatment. This tendency was detectable across the global data set, but held little predictive power for individual treatment combinations or within individual experiments. Although trade‐offs in the ability to respond to different global change treatments exert discernible global effects, other forces obscure their influence in local communities.

Number of simultaneously acting global change factors affects composition, diversity and productivity of grassland plant communities

“…These effects of co-acting GCFs are partly dependent on the identities of the co-acting GCFs, as indicated by increases in model fit (lower AIC values and higher log-likelihood values) when the GCF-identity models were compared to the null models (significant for biomass production of the transplanted-seedling communities and species composition and diversity of the sown communities; Tables 1 and 2 ). Yet, while individual effects of single-GCFs on plants can get weakened when combined with more and more other GCFs 47 , in contrast, overall effects of simultaneously acting GCFs might be especially pronounced at higher GCF numbers 25 , 43 . Therefore, to gain insight into general effects of GCF number, future studies should especially focus on higher numbers of combined factors.…”

“…However, clear unidirectional community shifts, as observed in response to individual factors [e.g., to drought; 45 ], may be less likely when different GCFs are acting simultaneously 46 . For example, while the exposure to an individual GCF will facilitate certain groups of species (e.g., deep-rooted species under dry conditions), trade-offs will likely limit a species’ ability to cope with multiple external stressors 47 . Therefore, as global change encompasses a wide range of factors differing in their properties 21 , it is unlikely that a large number of plant species can persist in ecosystems exposed to many GCFs.…”

Arbuscular mycorrhizal fungi enhance the drought resistance more significantly of the late‐successional psammophytes than that of the early ones

“…Early successional psammophytes are characterized by rapid settlement and adaptation to harsh habitats. However, late-successional psammophytes typically grow slower, allocate more resources to grow, and maintain nutrient structure to compete for more nutrient space for light and other resources (Langley et al 2022). Therefore, mycorrhizal promotion may be more needed by late-successional stages psammophytes.…”