NWT RESEARCH DATABASE

Regions: Inuvialuit Settlement Region, Gwich'in Settlement Area

Tags: physical sciences, climate change, ecosystem changes, plant productivity, tundra ecosystems

Objective(s): To investigate the differences in shrub productivity traits between undisturbed and disturbed tundra sites to better understand the impact of shrub expansion and disturbance on ecosystem function; and, To investigate the impact of shrub productivity trait differences on decomposition rates to improve our understanding of carbon and nutrient cycling after disturbance.

Project Description: This licence has been issued for the scientific research application No.5567. This project has two primary objectives: 1) To investigate the differences in shrub productivity traits between undisturbed and disturbed tundra sites to better understand the impact of shrub expansion and disturbance on ecosystem function. 2) To investigate the impact of shrub productivity trait differences on decomposition rates to improve our understanding of carbon and nutrient cycling after disturbance. For objective 1 methods are as follows: Sampling locations will be established at sites that have experienced disturbance (i.e., fire, thaw slumps, or polygonal terrain development) and adjacent sites that have not been disturbed. At these locations, individual shrubs will be selected from focal species (alder, birch, and willow) to measure photosynthetic rates (net CO2 exchange) and collect leaf and wood samples for later processing. Individual shrub stems will be sampled to estimate growth rates. Small soil samples will be collected (10cm diameter shallow cores) to determine soil moisture and organic layer thickness. Temperature loggers and nutrient probes will also be deployed to assess the environmental conditions of each site. Leaf and wood samples will be sent to Wilfrid Laurier University where they will be analyzed to measure relevant productivity traits such as nutrient content, wood density, and growth rate. Soils will be weighed to calculate soil moisture and analyzed for nutrient content. For objective 2 the methods are as follows: Additional soil and leaf samples will be collected from the sites established for objective 1. These materials will be transported to Wilfrid Laurier University where the soils will be used to isolate the microbial community responsible for decomposition (inoculum). Once isolated, inoculum will be applied to leaf litter from disturbed and undisturbed sites, placed in temperature-controlled growth chambers, and used to calculate rates of decomposition of litter from disturbed and undisturbed sites. The communication plan involves two key components: 1. Involvement of community members in research: Community involvement with members is the aim, as part of the research teams through collaboration with local guardian programs such as the Imaryuk monitors whenever possible. Opportunities will be provided for these individuals to be as involved in all stages of the research as they would like to be. Local wildlife monitors will be hired while conducting work on the Inuvik-Tuktoyaktuk Highway. 2. Communication of progress and results back to communities and NWT stakeholders: Data and findings will be conveyed to the community through a variety of plain language materials. Examples of this include, but are not limited to infographics, digital stories, and reports. Planned outreach also includes presentations at schools intended to engage youth in the research happening in their communities. All data will be made openly available and accessible to the public to ensure access by NWT stakeholders, communities, or future research teams. Data and publications will also be shared directly with interested ISR organizations. The fieldwork for this study will be conducted from: June 28 - September 15, 2023