Darwin Sodhi
Doctor of Philosophy in Forestry (PhD)
Research Topic
The role of pathogens in structuring forest communities in British Columbia
Elizabeth Wolkovich
Associate Professor
Research Classification
Research Interests
biodiversity
climate change
Conservation science
Global change
Plant communities
Plant invasions
Population and ecosystem ecology
Temporal ecology
Winegrapes
Relevant Thesis-Based Degree Programs
Affiliations to Research Centres, Institutes & Clusters
Graduate Student Supervision
Doctoral Student Supervision
Dissertations completed in 2010 or later are listed below. Please note that there is a 6-12 month delay to add the latest dissertations.
The importance of phylogeny and environment in shaping species phenologies (2024)
Climate change is having a considerable impact on the timing of species life history events (phenology). Most species phenologies are advancing, while other species phenologies are either not changing or occurring later in the year. Phenological shifts can alter the environment under which species grow and potentially produce asynchrony in species interactions. Accurate predictions of phenological change are essential to understanding how climate change will impact species and community dynamics. But as of yet, we lack consistent knowledge of what causes the observed high species variability, both across the tree of life and at the community-level. In my thesis, I performed a meta-analysis in which I combined phenological time-series for over 1200 species with data on their life history traits, evolutionary history, and geography. My findings illustrate the importance of accounting for species evolutionary history, but contrast the results of previous studies, as I failed to find strong trophic-level differences or geographic trends. To better understand the community-level drivers of phenological variation, I performed a controlled environment experiment using spring budburst in North American woody plants as a case study. Again I found strong phylogenetic structuring of species budburst, but little variation in environmental cues across populations. Despite accounting for the effects of the three primary cues of budburst, I found a considerable amount of unexplained variation across species, which suggests additional traits or environmental cues contribute to species budburst timing. In my final chapter I identify traits that could be driving this pattern. Combining six trait measurements with my experiment results, I tested whether phenology correlated with gradients in other traits and the growth strategies they infer. Only a subset of traits correlated with photoperiod, and none with temperature, suggesting that gradients in phenology do not align well with our current understanding of trait variability. The results of my thesis illustrate the high species-level variation in phenologies in response to climate, as well as the relative importance of phylogenetic structuring of phenology in improving our understanding of the mechanisms driving phenological variation.
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Master's Student Supervision
Theses completed in 2010 or later are listed below. Please note that there is a 6-12 month delay to add the latest theses.
Duration of interphenophases in winegrapes (2022)
Shifts in phenological events due to climate change have been widely studied. Yet, few studies have looked at interphenophases, the duration between two phenological events, and how they have been affected by climate change. This gap presents an opportunity to better understand both fundamental plant development and how climate change could impact it. Using hierarchical Bayesian modeling and a diverse dataset of winegrape varieties collected at Domaine de Vassal in the south of France, we determine how phenological events and interphenophases have changed since 1980. Overall event date advanced for budburst, flowering, veraison, and maturity as temperatures increased. Despite these advances, we found that most interphenophases lengthened: across all varieties budburst to flowering, veraison to maturity, and budburst to maturity lengthened while flowering to veraison remained the same. Among ripening classifications, we found no difference in change over time for budburst to flowering, veraison to maturity, or budburst to maturity, but found that for flowering to veraison, change in days per decade increased as ripening occurred later in the season. When looking at the growing degree days (GDD) of interphenophases, GDD increased for all phenological events and interphenophases. These results suggest that winegrape development may be limited by factors other than temperature, such as sugar accumulation during ripening. Moreover, we found high diversity in interphenophase rates of change among variety. While the diversity of winegrape varieties represents an important resource as vineyards prepare for changing climates, more work needs to be done to understand what characteristics are driving variety differences. Additionally, our GDD shifts indicate a need to revise GDD calculations to reflect how grapevines experience high temperatures.
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News Releases
This list shows a selection of news releases by UBC Media Relations over the last 5 years.
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UBC experts on heat and wildfires (29 Jul 2021)
Current Students & Alumni
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