Soil Nutrient Additions Shift Orthopteran Herbivory and Invertebrate Community Composition

Simple item page
dc.contributor.advisorHallett, Lauren
dc.contributor.authorAltmire, Gabriella
dc.date.accessioned2022-10-26T19:16:55Z
dc.date.issued2022-10-26
dc.description.abstractAnthropogenic alterations to global pools of nitrogen and phosphorus are driving declines in plant diversity across grasslands. As such, concern over biodiversity loss has precipitated a host of studies investigating how vertebrate herbivores affect the functioning of these nutrient enriched plant communities. However, there remains a dearth of empirical work cataloging (1) how invertebrate herbivores affect these communities, and (2) how invertebrate trophic structure responds to such communities. Here, I asked how long-term nitrogen (N) and phosphorus (P) enrichment affects Orthopteran herbivory and invertebrate community composition in a mountain meadow. First, I measured herbivory of two focal species—Bromus carinatus, a grass, and Lupinus latifolius, a legume—belonging to functional groups I hypothesized would increase and decrease, respectively, with nutrient enrichment. Then, I investigated whether nutrient induced changes in plant functional groups and habitat volume would change invertebrate trophic group abundances, including pollen/nectar-feeding herbivores, leaf-chewing herbivores, and parasitoids. I found that with both N and P additions, herbivory of B. carinatus increased, while herbivory of L. latifolius decreased, but only with N addition. Despite N quite drastically altering the plant community, it only changed one invertebrate trophic group surveyed, increasing nectar/pollen-feeding herbivore abundance. By increasing grass abundance, P increased both (non-Orthopteran) leaf-chewing herbivore and parasitoid abundances. These findings suggest that (1) in systems with an abundant grasshopper community, plant community response(s) to soil nutrient enrichment is likely influenced by its herbivory, and (2) in diverse, natural systems, invertebrate community response to global change is complex because trophic groups may respond differently to plant community change.en_US
dc.description.embargo2024-10-17
dc.identifier.urihttps://hdl.handle.net/1794/27794
dc.language.isoen_US
dc.publisherUniversity of Oregon
dc.rightsAll Rights Reserved.
dc.subjectHerbivoryen_US
dc.subjectInsecten_US
dc.subjectNitrogenen_US
dc.subjectPhosphorusen_US
dc.subjectPlanten_US
dc.titleSoil Nutrient Additions Shift Orthopteran Herbivory and Invertebrate Community Composition
dc.typeElectronic Thesis or Dissertation
thesis.degree.disciplineEnvironmental Studies Program
thesis.degree.grantorUniversity of Oregon
thesis.degree.levelmasters
thesis.degree.nameM.S.

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
Altmire_oregon_0171N_13463.pdf
Size:
2.37 MB
Format:
Adobe Portable Document Format
Download

Collections

Theses and Dissertations
Environmental Studies Theses and Dissertations