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Date of Award

Summer 2023

Document Type

Masters Thesis

Department or Program Affiliation


Degree Name

Master of Science (MS)



First Advisor

Zinkgraf, Matthew

Second Advisor

Miner, Benjamin G., 1972-

Third Advisor

Williams, Michael P.


In response to anthropogenic climate change, alpine floras in particular have been forecasted to shift their ranges upslope and north, yet recent analyses have shown otherwise. While a handful of floras have been found to track the trajectory of predictive models, most floristic elements have remained in their historical ranges despite a changing climate. Therefore, to improve the accuracy of models predicting range shifts, I address the following questions: (1) are mountain floras spatially structured through time; and (2) how are range dynamics of mountain floras changing through time. To address these questions, this study analyzed the herbarium records of 46 endemic alpine flora found in the Sierra Nevada Ranges of California. A permutational multivariate analysis of variance (PERMANOVA) was used to test the association between spatial similarities and similarities in collection time and/or elevation. The effect size of time and each environmental parameter (latitude, longitude, and elevation) were used to assess how range dynamics of alpine floras have changed over the past century. While the occurrence of some floras were found to be spatially structured and were considered to have been distributed latitudinally, longitudinally, and/or elevationally in relation to time, a majority of floras (89%) were found remaining in their historical ranges. Our results were found to be similar to recent analyses, suggesting the ranges of alpine floras have not tracked climate change as forecasted. If the rate of climate change is to follow the proposed trajectory, then species distribution models need to include the current distribution of species to accurately reflect future distributions and ultimately influence conservation decisions.




alpine plants, biodiversity, biogeography, california, climate change, endemism, historical records, macroecology, range dynamics, species distribution


Western Washington University

OCLC Number


Subject – LCSH

Alpine garden plants--Sierra Nevada (Calif. and Nev.); Biogeography--Sierra Nevada (Calif. and Nev.); Climatic changes--Sierra Nevada (Calif. and Nev.); Endemic plants--Sierra Nevada (Calif. and Nev.); Biodiversity

Geographic Coverage

Sierra Nevada (Calif. and Nev.)




masters theses




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