Diversity of wetland non-biting midges (Diptera: Chironomidae) and their responses to environmental factors in Alberta

• Author / Creator

  Liu, Qi

• Wetlands provide a wide range of services, including improving water quality, providing habitats for wildlife, and storing floodwaters. In Alberta, wetlands cover about 21% of the landscape of the province. In Alberta, as elsewhere, wetlands have suffered from human activities and many have declined in water quality and value as habitat. Non-biting midges (Diptera: Chironomidae) often dominate aquatic macroinvertebrate assemblages, both in number and diversity. They have been successfully used as indicators to assess water quality and human disturbance in streams. In contrast, the ecology of chironomids and value as indicators in wetlands are less explored. In this thesis, I use samples and environmental data from the Alberta Biodiversity Monitoring Institute (ABMI) to first explore what taxa of chironomids are present in Albertan wetlands. I created an atlas of all 40 chironomid genera identified, including a detailed glossary describing taxonomically important features of chironomids and a description of morphological and ecological features of each genus. This will provide baseline information and a good taxonomic tool for future chironomid studies in Alberta. Then I use multi- and univariate statistical approaches to assess the relationships between various aspects of chironomid community (i.e. chironomid assemblage structure, Shannon–Wiener index, total genus-richness, total abundance, and abundance of each genus) and both their associated habitats and measures of ‘human footprint’ (i.e., land with altered natural cover by human activities). Although several environmental factors and human footprint were identified as significantly correlated with chironomid variables, the overall relationships were weak (i.e. low variance explained). The weak correlation between chironomids and environmental variables could be due to the lack of important but unmeasured environmental variables, insufficient taxonomic resolution (i.e., responses may be clearer at species level), and/or that chironomids capable of living in wetlands in Alberta being robust generalists that are more tolerant of environmental variation than are chironomids associated with flowing water.

• Subjects / Keywords

  • Human footprint
  • Taxonomy
  • Wetlands
  • Freshwater invertebrate
  • Chironomidae
  • Biomonitoring
  • Indicators
  • Water quality

• Graduation date

  Spring 2016

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3ZP3W550

• 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.