Benthic Responses to Nitrogen and Phosphorus Deposition on Alpine Ponds in Banff National Park: A Replicated Whole-Ecosystem Experiment

• Author / Creator

  Porter, Lisa, L.

• Nitrogen (N) and Phosphorous (P) deposition at high elevations has increased by 40% over the last fifteen years, causing concern for the 3000+ alpine ponds in Banff National Park. A novel whole-ecosystem experiment was used to test for the effects of elevated N and P deposition on benthic communities in 16 ponds using a two-factor (N × P) experimental design. The findings showed periphyton was N-limited, as total chlorophyll was significantly higher in N- and NP-amended ponds, reflecting the positive response by algal groups. Periphyton appeared co-limited by N and P towards the end of the experiment, with strong grazing pressure by abundant populations of fairy shrimp (Branchinecta paludosa). The benthic consumer community consisted mainly of small omnivores (family Chironomidae) and large algal grazers (family Limnephilidae). These findings highlight the strong potential for eutrophication in the pristine high-elevation environments of the Canadian Rockies.

• Subjects / Keywords

  • Phosphorous deposition
  • Ponds
  • Benthic
  • Alpine
  • Canadian Rockies
  • Periphyton
  • Whole-ecosytem
  • Nutrient limitation
  • Nitrogen deposition

• Graduation date

  Fall 2012

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3F71P

• 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.