Degree
Master of Science
Program
Biology
Supervisor
Zoë Lindo
Abstract
Anthropogenic changes are causing shifts within soil food web communities, which may alter ecosystem processes such as nutrient cycling, carbon storage and decomposition. I quantified ecological stressor effects on the abundance, richness, community composition and body size of a soil-dwelling microarthropod (Collembola: Hexapoda). I quantified the effects of warming and nitrogen deposition in two separate field studies and demonstrated that warming shifts Collembola community structure and decreases community body size. I quantified the interactive effects of top-down and bottom-up forces mediated by warming as ecological stressors in Collembola communities. I found that bottom-up effects of nutrient addition did not affect Collembola abundance, richness or community composition, while warming and predator addition interactively reduced abundance and shifted community composition. I demonstrate that top-down and warming effects independently and interactively reduce Collembola density and homogenize community structure. These findings suggest that top-down effects and warming can affect communities in soil food webs and may impact soil ecosystem processes.
Recommended Citation
Kustec, Jordan, "Top-down and bottom-up effects on Collembola communities in soil food webs" (2018). Electronic Thesis and Dissertation Repository. 5906.
https://ir.lib.uwo.ca/etd/5906