Date of Award

2026-05-01

Degree Name

Doctor of Philosophy

Department

Biological Sciences

Advisor(s)

Jennie McLaren

Abstract

Herbivores are essential drivers of above and belowground processes in ecosystems across the globe. Through their effects on ecosystem processes, herbivores represent a critical force shaping ecosystems undergoing rapid environmental changes, such as the Arctic. However, there are critical gaps in our knowledge of herbivores as drivers of Arctic ecosystem processes, especially concerning the role of small mammal herbivores. While previous research has made significant strides in identifying the role of small mammal herbivores as both top down and bottom up forces in Arctic ecosystems, we still lack an understanding that explicitly connects plant and soil responses to herbivory, especially across decadal time scales. Additionally, the conclusions of previous research have been constrained by focusing on the presence and absence of herbivory rather than the duration and intensity of herbivory. To understand the direct and indirect effects of small mammal herbivory on Arctic ecosystem processes, I first investigate plant community nutrient and soil biogeochemical responses to 60 + years of small mammal herbivore exclusion in the tundra near Utqiaġvik, Alaska in Chapter 2. In Chapter 3, I explore the role of small mammal structures (e.g. hay piles, runways, latrines, etc.) in changing the inherent links between plants and soils near Utqiaġvik, Alaska. Lastly, I investigate how the duration and intensity of herbivory affect individual plant chemistry in Chapter 4 and the rates of nutrient release and mass loss during litter decomposition in Chapter 5. Together, this dissertation provides a holistic view of the role of small mammal herbivores in driving Arctic ecosystem processes that explicitly links aboveground and belowground responses.

Language

en

Provenance

Received from ProQuest

File Size

173 p.

File Format

application/pdf

Rights Holder

Andrew Uccello

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