Getting to the Root of the Problem: Below-ground Drivers of Grassland Plant Community Resilience Under Increasing Drought
Climate predictions suggest greater drought intensity and duration, and greater soil water limitation in grasslands worldwide. Determining how plant traits mediate vegetation responses to climate change is essential to predicting future grassland plant population and community dynamics.
Our previous and on-going research shows that rhizosheaths, mycorrhizas, and root architecture co-vary among and within plant species in grassland communities, and soil moisture is a key driver of trait expression. However, relative to aboveground plant traits, we know little about the significance of belowground trait variation as a predictor of plant community resilience to altered precipitation regimes. Elucidation of these alternative and potentially complementary plant traits will be invaluable to grassland conservation and restoration; absence of this knowledge will constrain our ability to predict and maintain plant community diversity, ecosystem services, and associated human livelihoods in a changing world.
The overall objective of this RaMP research integrates complementary field and greenhouse experiments, linking belowground traits to individual grassland plant, population, and community responses to drought, improving predictions of grassland sensitivity or resilience under increasing aridity. Our central hypothesis is belowground traits vary with local climate and soil conditions, with plant communities composed of species utilizing multiple belowground strategies being relatively species rich, diverse and stable.
Research questions to aid conservation, management, and restoration of grasslands might include the following:
- How do belowground traits of individual plant species vary across edaphic and resource gradients?
- How do root traits (rhizosheaths, mycorrhizas, and root system architecture) of individual plants influence grassland community assemblages across precipitation gradients?
- Does soil texture or drought severity/frequency influence how rhizosheaths, mycorrhizas, and root system architecture interact and co-vary in response to soil moisture limitations?
Based on the fellow’s interests, experience can be gained in field, laboratory, and greenhouse studies, learning tools including plant survey methods, experimental design, grassland plant identification, microscopy, molecular analysis for soil microbiomes, etc.
Network Mentor: Dr. Gail Wilson