Soil degradation: Microbial inoculation strategies to restore the skin of the earth
Roxanne Márquez, B.S. Biology & Dr. Jennifer Rudgers
Department of Biology UNM 2024
setting up experiment
biocrust sample
greenhouse experiment setup: biocrusts in heat chambers
What are biological soil crusts (biocrusts) and why do I study them?
Biocrusts are microbial communities that live on the soil surface and can be comprised of cyanobacteria, lichens, mosses, and fungi, among other microbes.
Biocrusts are important for:
carbon sequestration
fixing atmospheric nitrogen
nutrient and water retention
preventing erosion by stabilizing the soil
The microbial communities found in biocrusts contribute to the overall soil health of drylands, yet these soils are susceptible to degradation from trampling disturbances and progressing heat stress due to climate change.
With this project, I investigate how inoculating biocrusts with native cyanobacteria and fungi can possibly help restore soils from past degradation and help resist heat stress.
Microcoleus steenstrupii cyanobacteria
Microcoleus vaginatus cyanobacteria in culture
Septate hyphae (fungi) in liquid agar culture
How did I conduct the experiment?
Top-soils with a legacy of degradation or no degradation (control soils) were collected from the Sevilleta National Wildlife Refuge on the Biocrust Degradation Experiment plots.
Half of each legacy treatment were subjected to 25°C or 35 °C in greenhouse heat chambers
Soils were inoculated with combinations of native cyanobacteria and fungi
These microbial treatments involved 2 species of cyanobacteria, some inoculations were single species and some were both species combined. These inoculations also involved the presence or absence of fungi culture addition as well; this was to test whether the addition of fungi positively or negatively affects soil health in combination with these cyanobacteria inoculations.
Contact me if you want to learn more about this project or discuss the results!