How do soil organisms affect plant species interactions and coexistence?

We’ve been conducting a series of experiments aimed at understanding the complex interactions between plants and the soil ecosystems in which they are rooted.   We use a combination of greenhouse experiments, field experiments, common garden experiments, sequencing technologies, ecological theory, and statistical modeling.

Recent work led by Jeremy Collings, Macy Patel and Austyn Tavernier has explored how rhizobia, mycorrhizal fungi and drought interact to influence plant performance, species interactions and coexistence.

Key references:

• Collings, J. A., Cook, E. J., Delevich, C. A., & Diez, J. M. (2024). Soil mycobiome dissimilarity, independent of fungal guild, is associated with increased probability of plant coexistence. Journal of Ecology, 00, 1–12. https://doi.org/10.1111/1365-2745.14396

Previous work led by Courtney Collins in the White Mountains of California (beautiful!) explored how plant-soil feedback legacies impact plant community dynamics in the alpine.

Key references:

• Collins, C., Spasojevic, M., Alados, C., Aronson, E., Benavides, J., Cannone, N., Caviezel, C., Grau, O., Guo, H., Kudo, G., Kuhn, N., Müllerová, J., Phillips, M., Pombubpa, N., Reverchon, F., Shulman, H., Stajich, J., Stokes, A., Weber, S., Diez, J. (2020) Belowground Impacts of Alpine Woody Encroachment are determined by Plant Traits, Local Climate and Soil Conditions. Global Change Biology
• Collins, C*., Bohner, T.* & Diez, J. (2019). Plant-soil feedbacks and facilitation influence the demography of herbaceous alpine species in response to woody plant range expansion. Frontiers in Ecology and Evolution, 7, 417.
• Collins, C.G*., Stajich, J.E., Weber, S.E., Pombubpa, N. & Diez, J.M. (2018). Shrub range expansion alters diversity and distribution of soil fungal communities across an alpine elevation gradient. Molecular Ecology, 27, 2461–2476.
• Collins, C.G., Spasojevic, M.J., Pombubpa, N. et al. Legacy effects post removal of a range-expanding shrub influence soil fungal communities and create negative plant-soil feedbacks for conspecific seedlings. Plant Soil 485, 143–165 (2023). https://doi.org/10.1007/s11104-023-05896-w