|Our high elevation mixed conifer site|
|A natal site for blue grama in the middle of monsoon season|
|Ponderosa Pine growing at its|
To address these issues my research uses common gardens across an elevation gradient with several unique soils. We are focusing on two important plant species in the southwest, Bouteloua gracilis (Blue grama) and Pinus ponderosa (Ponderosa Pine). We grow plants in the following soil and soil organism combinations 1) natal soil with home team soil organism, 2) natal soil with away team soil organism, 3) novel soil with home team soil organisms, and 4) novel soil with away team soil organisms. Each one of these treatment combinations is then planted at the plants home site and then two sites of lower elevation to simulate warming and two sites at higher elevation to simulate cooling, a phenomena a plant may experience in assisted migration or rapid natural migration. One generalized hypothesis is that plants will be dependent on their home team soil organisms when adapting to novel environments, especially when the novel environment is stressful. Thus we expect to find that soil organisms from the plant's home site help alleviate limitations in plant growth when plants are moved to higher or lower elevations and when plants are grown in novel soil environments.
In the past, we have conducted smaller projects to address the following questions:
- Can soil organisms from a dry environment facilitate plant adaptation to drought?
- Does cheatgrass change soil organism communities in a way that has a lasting negative legacy on the native blue grama?
We also found that soil organisms communities that had bee manipulated by cheatgrass inhibiting growth of blue grama, even relative to sterile controls. This is likely due to the combined effects of reduced mycorrhizal fungi abundance and the presence of soil pathogens.
Both these findings support the idea that in both adaptive management and ecological restoration, pairing plants with their home team soil organisms enhance plant growth relative to pairing plants with the soil organisms present in their novel environment. These studies show the role soil organisms play in facilitating plant adaptation to novel environments created in climate change and plant migration scenarios or those created by the invasion of exotic plant species.
|A low elevation desert grassland site being used in our experimental garden|