Master of Science
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.
Kustec, Jordan, "Top-down and bottom-up effects on Collembola communities in soil food webs" (2018). Electronic Thesis and Dissertation Repository. 5906.