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Biology subjects

Almeida, B. K.

Publications and source records attributed to Almeida, B. K..

3 recordsLinked to original sources

The microbial landscape: soil microbiome properties predict plant species distributions

Plant species distributions are shaped by interactions with the abiotic and biotic environment. Despite the known importance of soil microbiomes in shaping plant diversity and function, no study has explicitly determined the ability of the soil microbiome to predict plant species distributions at large scales. We employed paired above- and belowground surveys of plant occurrence and soil microbial taxa and functions across habitat patches (n = 676), applying machine-learning-based distribution modeling to identify the relative influence of the soil microbiome and environmental attributes in predicting plant species (n = 50) distributions across the landscape. We discovered that while abiotic gradients of known importance in this ecosystem were the strongest predictors of many plant species distributions, microbial predictors could have similar or greater influence. Microbiome predictors were collectively more important than abiotic environmental variables for 38% of plant species in this study and explained >70% of the predicted distribution for one species. We identified four microbiome attributes of landscape-scale importance for predicting plant species distributions including prokaryotic richness, fungal richness, the abundance of fungal pathogens, and the abundance of prokaryotic phosphate transport genes in soil. Our findings reveal a previously underappreciated role of the soil microbiome in shaping plant species distributions at a landscape scale, with implications for plant community structure in the context of both ecosystem restoration and future global change.

ecology↗

Phyllosphere fungal diversity generates pervasive non-additive effects on plant performance

O_LIAll plants naturally harbor diverse microbiomes that can dramatically impact their health and productivity. However, it remains unclear how microbiome diversity, especially in the phyllosphere, impacts intermicrobial interactions and consequent non-additive effects on plant productivity. C_LIO_LICombining manipulative experiments, field collections, culturing, microbiome sequencing, and synthetic consortia, we experimentally tested for the first time how foliar fungal community diversity impacts plant productivity. We inoculated morning glories with 32 synthetic phyllosphere communities of either low or high diversity or with single fungal taxa, and measured effects on plant productivity and allocation. C_LIO_LIWe found 1) non-additive effects were pervasive with 56% of microbial communities interacting synergistically or antagonistically to impact plant productivity, including some consortia capable of generating acute synergism (e.g., >1000% increase in productivity above the additive expectation), 2) interactions among commensal fungi were responsible for this non-additivity in diverse communities, 3) synergistic interactions were ~4 times stronger than antagonistic effects, 4) fungal diversity affected the magnitude but not frequency or direction of non-additivity, and 5) diversity affected plant performance nonlinearly with highest performance in low microbial diversity treatments. C_LIO_LIThese findings highlight the importance of interpreting plant-microbial interactions under a framework that incorporates intermicrobial interactions and non-additive outcomes to understand natural complexity. C_LI

ecology↗

Multidimensional specialization and generalization are pervasive in soil prokaryotes with generalists dominating communities and specialists more central in networks

Habitat specialization underpins biological processes from species distributions to speciation. However, organisms are often described as specialists or generalists based on a single niche axis, despite facing complex, multidimensional environments. Here, we analyzed 236 prokaryotic communities across the United States demonstrating for the first time that 90% of >1,200 prokaryotes followed one of two trajectories: specialization on all niche axes (multidimensional specialization) or generalization on all axes (multidimensional generalization). We then documented that this pervasive multidimensional specialization/generalization had a wide range of ecological and evolutionary consequences. First, multidimensional specialization and generalization are highly conserved with very few transitions between these two trajectories. Second, multidimensional generalists dominated communities because they were 73 times more abundant than specialists. Lastly, multidimensional specialists played important roles in community structure with [~]220% more connections in microbiome networks. These results indicate that multidimensional generalization and specialization are evolutionarily stable with multidimensional generalists supporting larger populations and multidimensional specialists playing important roles within communities likely stemming from their overrepresentation among pollutant detoxifiers and nutrient cyclers. Taken together, we demonstrate that the vast majority of soil prokaryotes are restricted to one of two multidimensional niche trajectories, multidimensional specialization or multidimensional generalization, which then has far-reaching consequences for evolutionary transitions, microbial dominance, and community roles. One-Sentence SummaryPervasive multidimensional specialization and generalization impacts evolutionary trajectories, microbial dominance, and community roles.

microbiology↗