Quantifying the insect and microbial diversity supported by native and introduced trees on a large urban university campus
department or school: Science, Faculty of
department or school: Botany, Department of
data provider: DSpace
degree campus: UBCV
creator: Grewal, Devlin Singh
issued: 2025-09-02T16:23:19Z
issued: 2025
related degree: Master of Science - MSc
degree grantor: University of British Columbia
description: Urban forests, the trees that are planted and managed within built-up areas, provide valuable services to humans and wildlife, including lowering air temperature, carbon sequestration, improved quality of life for humans, and habitat and resources for insect, birds, and other animals. However, tree species planted within these forests are often selected for aesthetics or their ability to tolerate urban stressors, and are dominated by introduced tree species. Whether the selected trees can support urban biodiversity has largely been ignored. Trees are host to important plant-dependent organisms such as leaf-feeding insects and epiphytic microbes. These organisms are important for nutrient cycling, pest control, and tree health. Limited previous research suggests that tree provenance (i.e. native or introduced) might affect the diversity of insects and microbes supported by specific trees. Native trees are hypothesized to be a more palatable resource for phytophagous insects (and hence support a higher diversity and abundance of insects) but evidence linking tree provenance to microbial diversity or community composition is mixed. This thesis tests the hypothesis that native and introduced trees support unique communities of insects and microbes. In 2023 we sampled insect communities throughout the growing season from 80 trees (16 tree species) on the University of British Columbia Vancouver campus. We also sampled the leaf bacterial community once from each tree. We found the same overall abundance of insects on native and introduced trees, but native trees supported higher insect richness. Functional diversity and insect community composition also differed between native and introduced trees. Tree provenance did not affect microbial richness or community composition. Insect and microbial community composition were also unique between the coniferous and deciduous hosts. Overall, our findings indicate that native trees support higher insect diversity than their introd…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/92173
note: QUANTIFYING THE INSECT AND MICROBIAL DIVERSITY SUPPORTED BY NATIVE AND INTRODUCED TREES ON A LARGE URBAN UNIVERSITY CAMPUS by Devlin Singh Grewal B.Sc., The University of Toronto, 2022 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE in THE FACULTY OF GRADUATE AND POSTDOCTORAL STUDIES (Botany) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) August 2025 © Devlin Singh Grewal, 2025 ii The following individuals certify that they have read, and recommend to the Faculty of Graduate and Postdoctoral Studies for acceptance, the thesis entitled: QUANTIFYING THE INSECT AND MICROBIAL DIVERSITY SUPPORTED BY NATIVE AND INTRODUCED TREES ON A LARGE URBAN UNIVERSITY CAMPUS submitted by Devlin Singh Grewal in partial fulfilment of the requirements for the degree of Master of Science in Botany Examining Committee: Dr. Michelle Tseng, Assistant Professor, Botany, UBC Co-supervisor Dr. Danielle Ignace, Associate Professor, Forest Resources, University of Minnesota Co-supervisor Dr. Matthew Mitchell, Assistant Professor, Forest Resources Management, UBC Additional Examiner Additional Supervisory Committee Members: Dr. Warren Cardinal-McTeague, Forest and Conservation Sciences, UBC Supervisory Committee Member Dr. Laura Parfrey, Associate Professor, Zoology, UBC , Supervisory Committee Member iii Abstract Urban forests, the trees that are planted and managed within built-up areas, provide valuable services to humans and wildlife, including lowering air temperature, carbon sequestration, improved quality of life for humans, and habitat and resources for insect, birds, and other animals. However, tree species planted within these forests are often selected for aesthetics or their ability to tolerate urban stressors, and are dominated by introduced tree species. Whether the selected trees can support urban biodiversity has largely been ignored. Trees are host to important plant-dependent organisms such as leaf-feeding insects and epiphytic mi…
has type: Thesis/Dissertation
date issued: 2025-11
is shown at: 10.14288/1.0449965
language: eng
degree discipline: Botany
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
contributor: Tseng, Michelle
contributor: Ignace, Danielle
type: Text
identifier URI: http://hdl.handle.net/2429/92173