Project Type

URC Presentation

College or School


Class Year



Natural Resources and the Environment


Sustainable Agriculture

Faculty Research Advisor

Serita Frey


Global change effects carbon (C) cycling, but interactions between abiotic and biotic stressors may determine sizes of soil C pools. The invasive plant Alliaria petiolata (garlic mustard) can reduce soil C contents and suppress plant growth. Abiotic stressors might interact with this biotic invasion to diminish specific soil C pools, such as fine roots, a sizeable reservoir of C. We implemented a full factorial experimental A. petiolata invasion into a decadal soil warming (H) ´ nitrogen (N)-deposition experiment at the Harvard Forest Long Term Ecological Research Site (LTER). Soils were collected from replicate plots in June 2016, and fine roots were picked from both organic and mineral soil horizons. I hypothesized that plots invaded by A. petiolata would have lower fine root biomass and the effect would enhance across all abiotic treatments. In support for my hypothesis, I found that A. petiolata invasion reduced fine root biomass and interacted with simulated N-deposition to further diminish fine roots. In contrast, I did not observe this in H plots or plots where H and N interacted. Biotic invasion interacts with abiotic stressors with more complexity than formerly believed and will impact fine roots differently in a warmer, fertilized environment.