NWT RESEARCH DATABASE

Regions: Sahtu Settlement Area

Tags: aquatic ecosystems, climate change, permafrost thaw, Ts'ude Niline Tu'eyeta, Wildfire Effects, cumulative impacts

Objective(s): to evaluate responses of aquatic ecosystems to permafrost thaw, lake drying, and wildfire, as well as their cumulative impacts.

Project Description: This licence has been issued for the scientific research application No. 5646. This project proposes to evaluate responses of aquatic ecosystems to permafrost thaw, lake drying, and wildfire, as well as their cumulative impacts. The researchers will characterize lake chemistry and biological diversity (microbes and invertebrates) in water (current environmental change) and in sediments (historical change), focusing on a set of lakes that vary in expected degree of change. Specifically, four objectives have been identified to be addressed through a combination of short-term, directed research studies and longer term monitoring efforts: 1- Characterize changes in water chemistry (including metals and contaminants) and biological diversity (bacteria and invertebrates) over a wide range of aquatic ecosystems in the vicinity of Fort Good Hope (FGH) and Ts'ude Niline Tuyeta, 2- Characterize changes in these ecosystem measures over longer time periods by investigating lake sediments, 3- Compare patterns in water chemistry and aquatic diversity to other locations in the NWT to consider implications at a broader spatial scale, and 4-Evaluate influences of stressors on surface water quantity and quality to assess the vulnerability of lakes to serve as drinking water source. To identify how aquatic ecosystems respond to environmental stressors such as permafrost thaw and wildfire, separately and in combination, the study will focus on wetlands within the protected area and near FGH. Wetlands are commonly seen as sentinels of changes occurring in the surrounding landscape. Whereas some of these ecosystems in the area have already been impacted by a wide range of human activities, including development of oil and gas and associated infrastructure, others such as Ts'ude Niline Tu'eyeta have been protected from anthropogenic disturbance. Similarly, the region lies in discontinuous permafrost, which suggests that some aquatic ecosystems directly impacted by thawing permafrost (lakes are drying) while others do not. For both areas, surface water will be sampled and analyzed for water chemistry (e.g. DOM, nutrients and metals) at Taiga laboratories in Yellowknife, bacteria and invertebrates’ diversity across both gradients. Invertebrates identification will be performed by students from FGH school as initiated and supervised by Gurney in past studies. Diversity of bacteria will be performed at INRS. What remains unknown is if these waterbodies have experienced comparable perturbation in the past. To this end, sediment cores will be collected at each sites. The structure of the cores will be analyzed at INRS and the bacterial diversity will also be analysed at INRS. Environmental stressors can affect surface waters used as drinking water source for the community. Variability of source water quality can affect water treatment ability to meet territorial requirements in term of drinking water quality. Therefore a vulnerability analysis will be conducted by Dr. Guilherme around water sources. This analysis will identify threats, such as activities or natural or anthropogenic events that can affect the quality or quantity of source water and potentially drinking water. These threats can be sources of water contamination or potential hazardous events impacting source integrity. Permafrost data will be collected and analyzed by Dr. Rudy, Northwest Territories Geological Survey. During a visit in Fort Good Hope in January 2023, the project lead met in person and discussed this proposal with the K’asho Gotine Foundation president (Mr. Daniel Masuzumi) and his team, the president of Fort Good Hope Renewable Resource Council (Mr. Daniel Jackson) and his team, the Executive Director of the Sahtu´ Land and Water Board (Mr. Paul Dixon). The goal of the meeting was to assess the interest and level of support from the community for the project and the support was extremely strong as the health of aquatic ecosystems is of great concern in the community. The collaboration and support from the community members and agencies of Fort Good Hope is critical for this project. To maintain this good relationship, we collaboratively built a research plan, and continue to work together through regular meetings and written communications. Our engagement is driven by community voices and preferences ensuring equal opportunity for all. Engagement activities may include but are not limited to: community meals, site visits, instrumental measurements, regular results sharing meetings (usually during winter time), and other methods as agreed on by community and research team members. The community’s partnership will be acknowledged in all communications and results will be shared with the communities through meetings and plain language reports. Data will be made available through the Mackenzie DataStream. The fieldwork for this study will be conducted from: June 05 - December 31, 2023