Temperate conifer forests, like those in western North America, are important for storing carbon and helping reduce climate change. But severe drought and more frequent, intense wildfires are threatening these forests’ ability to store carbon, provide homes for animals, and supply wood for building.
A forest’s recovery from fire and drought depends on how its trees and soil microbes respond to stress. Scientists know that extreme drought and fire conditions affect how trees take in carbon, use water, and distribute nutrients. They also know these events change how microbes in the soil function. However, they don’t fully understand how trees and microbes work together to deal with these stresses.
EMBER uses lab, greenhouse, field, and modeling experiments to reveal how tree and microbe communities respond to drought and fire, and how those stressors shape interactions between trees and microbes. EMBER examines these questions at multiple levels, from the microscopic scale (such as inside cells) all the way up to how entire forests function. This six-year research project (2024-2030) will enhance predictions of how forests will cope with future droughts and fires, and help to better protect and manage these valuable ecosystems.
EMBER field work takes place in the University of Idaho Experimental Forest. The study includes two types of pine trees that are common in western forests (ponderosa pine and Douglas fir) and three types of microbes found in the soil (Methylobacterium extorquens, Edaphobacter flagellatus, and Bacillus pumilus).
Specific goals
- Examine how drought and fire influence conifer seedling survival and physiological responses.
- Uncover how stressors alter gene expression, growth, and survival of the three microorganisms in laboratory tests, and extend these results to natural soils.
- Experimentally evolve each model microorganism in the presence of individual and combined stressors to determine the pace and targets of rapid adaptation.
- Explore how stressors affect microbial community assembly and function.
- Investigate seedling-microbe interactions by testing how individual microoganisms, synthetic communities, or natural communities impact the establishment, growth, and survival of ponderosa pine and Douglas fir seedlings.
- Test the hypothesis that mature tree microbiome communities employ the same stress-response strategies as seedlings. This part of the project will exclude precipitation to amplify natural drought and ignite controlled fires on 24 mature trees in the study area.
- Use models to understand how forests may reorganize in the future when microbiome processes and their interactions with trees are represented.
By addressing these questions, EMBER will generate the fundamental knowledge and modeling required to predict whether a particular tree, or forest, will survive a fire or drought event, and how compounding stressors will impact forest function and carbon storage. Furthermore, EMBER provides the level of experimental-model integration needed to make critical science-based recommendations for carbon offset markets.