Tadashi Fukami, Doctoral (Program)
- Ontogenetic antagonism-mutualism coupling: perspectives on resilience of stage-structured communities OIKOS 2018; 127 (3): 353–63
- Statistical recipe for quantifying microbial functional diversity from EcoPlate metabolic profiling ECOLOGICAL RESEARCH 2018; 33 (1): 249–60
Species coexistence through simultaneous fluctuation-dependent mechanisms.
Proceedings of the National Academy of Sciences of the United States of America
Understanding the origins and maintenance of biodiversity remains one of biology's grand challenges. From theory and observational evidence, we know that variability in environmental conditions through time is likely critical to the coexistence of competing species. Nevertheless, experimental tests of fluctuation-driven coexistence are rare and have typically focused on just one of two potential mechanisms, the temporal storage effect, to the neglect of the theoretically equally plausible mechanism known as relative nonlinearity of competition. We combined experiments and simulations in a system of nectar yeasts to quantify the relative contribution of the two mechanisms to coexistence. Resource competition models parameterized from single-species assays predicted the outcomes of mixed-culture competition experiments with 83% accuracy. Model simulations revealed that both mechanisms have measurable effects on coexistence and that relative nonlinearity can be equal or greater in magnitude to the temporal storage effect. In addition, we show that their effect on coexistence can be both antagonistic and complementary. These results falsify the common assumption that relative nonlinearity is of negligible importance, and in doing so reveal the importance of testing coexistence mechanisms in combination.
View details for DOI 10.1073/pnas.1801846115
View details for PubMedID 29895689
- Linking modern coexistence theory and contemporary niche theory ECOLOGICAL MONOGRAPHS 2017; 87 (2): 161-177
The soil microbial community predicts the importance of plant traits in plant-soil feedback
2015; 206 (1): 329-341
Reciprocal interaction between plant and soil (plant-soil feedback, PSF) can determine plant community structure. Understanding which traits control interspecific variation of PSF strength is crucial for plant ecology. Studies have highlighted either plant-mediated nutrient cycling (litter-mediated PSF) or plant-microbe interaction (microbial-mediated PSF) as important PSF mechanisms, each attributing PSF variation to different traits. However, this separation neglects the complex indirect interactions between the two mechanisms. We developed a model coupling litter- and microbial-mediated PSFs to identify the relative importance of traits in controlling PSF strength, and its dependency on the composition of root-associated microbes (i.e. pathogens and/or mycorrhizal fungi). Results showed that although plant carbon: nitrogen (C : N) ratio and microbial nutrient acquisition traits were consistently important, the importance of litter decomposability varied. Litter decomposability was not a major PSF determinant when pathogens are present. However, its importance increased with the relative abundance of mycorrhizal fungi as nutrient released from the mycorrhizal-enhanced litter production to the nutrient-depleted soils result in synergistic increase of soil nutrient and mycorrhizal abundance. Data compiled from empirical studies also supported our predictions. We propose that the importance of litter decomposability depends on the composition of root-associated microbes. Our results provide new perspectives in plant invasion and trait-based ecology.
View details for DOI 10.1111/nph.13215
View details for Web of Science ID 000350347500033
View details for PubMedID 25521190
- Incorporating the soil environment and microbial community into plant competition theory. Frontiers in microbiology 2015; 6: 1066-?