Impacts of road dust on Arctic lakes

Northern Canada is experiencing rapid environmental change as the climate warms and permafrost thaws. These changes are having an impact on terrestrial and aquatic ecosystems in the Northwest Territories. In addition to climate change, the development and maintenance of roadways is another stressor that is affecting northern ecosystems. Many northern highways are unpaved gravel roads which generate large amounts of dust and debris that end up in the surrounding soil and water. Recent studies show that road dust can change water quality in roadside lakes, but little research has been done to examine how these changes might influence aquatic food webs in Arctic lakes. For my thesis, I will study how climate change and development are affecting water quality and zooplankton communities found in small lakes adjacent to the Dempster and Inuvik-Tuktoyaktuk Highways, in the Northwest Territories. The main objectives of my thesis are to: 1) Determine the effects of road dust and road proximity on aquatic zooplankton communities; and (2) Determine if the type of roadside vegetation (boreal vs. tundra) mediates changes in water quality and zooplankton in roadside lakes. To achieve these objectives, I will collect physical, biological, and chemical data for forty lakes that are located at a range of distances from the roadway. Using the resulting dataset, I will examine patterns in major water quality variables in relation to road proximity and I will construct statistical models relating zooplankton communities to the physical and chemical properties of each lake. Finally, I will determine if the richness, diversity, and abundance of zooplankton is affected by road proximity using linear regression models. The results of my study will allow me to assess how road proximity affects zooplankton biodiversity in northern lakes and will be valuable for environmental managers who are responsible for evaluating the impacts of proposed roadway developments in Canada’s north.

Associated students: Natasha Hannan, Vivian Gao