Mitigating the Impacts of Climate Change on Rare Plants through Assisted Migration

• Author / Creator

  Pedersen, Jennine L.M.

• Given high levels of human disturbance and projected rates of climate change, many species will be unable to keep pace with their shifting climatic ranges and thus face increased risk of extinction. This research investigated the use of assisted migrations for two rare and range-restricted plant species in Alberta: Houstonia longifolia and Liatris ligulistylis. The reproductive ecology of the distylous species Houstonia longifolia was also investigated to better understand limitations in reproduction and to help develop more successful conservation strategies. Assisted migration trials for both Houstonia longifolia and Liatris ligulistylis involved the translocation of mature plants and seeds to replicate sites at each of four geographic locations along a north-south gradient in Alberta being both south (future warming) and north (future climatic habitat) of the species current range. Houstonia longifolia flower morph ratios were more pin biased in small populations with seed production varying by morph type and proportion of plants in the surrounding area with pin flower morphs. As the proportion of pins increased, seed production increased in thrums, while decreasing in pins. This demonstrates that Houstonia longifolia has a self-incompatibility system that requires the presence of opposite floral morphs for maximum seed production. The assisted migrations of Houstonia longifolia resulted in 6.2% of adult plant survival from mostly within its current range and no seed germination at any site. In contrast, Liatris ligulistylis adult plants and seed were able to grow and establish hundreds of kilometers outside of their current range. Results suggest that Liatris ligulistylis may be out of equilibrium with the climate in its current range with some measures of plant performance best 500 km north of its current range. The inclusion of soil from source locations also improved plant performance. Translocation of plants with source soil may therefore improve the success of these and future assisted migrations. It is hoped that through the continuation of these trials, assisted migrations will become a more recognized and utilized conservation strategy to prevent the loss of biodiversity.

• Subjects / Keywords

  • Assisted migration
  • Houstonia longifolia
  • Liatris ligulistylis
  • Flower morph ratio
  • Distylous
  • Seed production
  • Climate change

• Graduation date

  Fall 2015

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3W950T4M

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.