Base de données de recherche des TNO

étiquettes: environmental impact, landscape disturbance, hydrology, slumping, risk assessment, cumulative effects, permafrost thaw, anthropogenic impacts, disturbance mapping

Objectif(s): To inventory and track broad scale changes in landscape disturbances; to determine the impacts of natural and anthropogenic disturbances on the physical and chemical characteristics and ecology of streams and rivers; to determine disturbance thresholds relevant to the health of streams and fish; and to compile geospatial disturbance layers and portray this information on a watershed basis as a platform for evaluating risk and cumulative impacts to aquatic systems.

Description du projet: This is a multidisciplinary project involving communities, governments and academic researchers. The goals are to: 1) inventory and track broad scale changes in landscape disturbances; 2) determine the impacts of natural and anthropogenic disturbances on the physical and chemical characteristics and ecology of streams and rivers; 3) determine disturbance thresholds relevant to the health of streams and fish; and 4) compile geospatial disturbance layers and portray this information on a watershed basis as a platform for evaluating risk and cumulative impacts to aquatic systems. Objective 1: Inventory and track the distribution and activity of thaw slumps. The purpose of this component of the project is to determine patterns of thaw slump distribution and assess if the current distribution, number and size of slumps (and mega-slumps) has increased since the 1940s (first year of available air photographs). The temporal patterns of slump growth will also be investigated with respect to climatic parameters including temperature and precipitation. Mapping the distribution of slumps will also help to identify geological or environmental controls that can be used to produce sensitivity maps that will inform infrastructure planning and decision making. Disturbance maps will also allow us to estimate the magnitude of thermokarst impact on regional hydrological networks. A series of thematic maps will be produced for the community, the Department of Fisheries and Oceans, the Department Of Transportation and published at the NWT Geoscience office in geospatial format. Objective 2: Determine the impacts of natural and anthropogenic disturbances on the physical and chemical characteristics. This objective involves investigation of the impacts of mega-slumps and other smaller disturbances on the hydrological regime, sediment load and geochemistry of local fish bearing streams in the Peel Plateau. This objective will be accomplished by monitoring flow and turbidity and analyzing water quality in undisturbed streams, and in those impacted by mega- and smaller slumps of varying intensities as well as streams flowing over stabilized slumps. The research team will monitor flow and analyze water quality (major and trace cations, anions, stable O-H-C isotopes) and nutrients (DO, phosphate, nitrogen) of runoff from varying sources (surface and subsurface flow from disturbances of varying type and age) and geochemical tracers will be utilized to determine the relative impacts of different disturbance types (Cumulative impacts) on stream water quality. The research team will identify geochemical tracers (indicators) that can be used to track and quantify the relative contribution of slump runoff in the respective watersheds and in the Peel River utilizing geochemical hydrograph separation techniques. Long-term geochemical trends will also be investigated through statistical analysis of the 40-year Peel River water chemistry data set and causes of changes to water quality will be explored. The Gwich’in Tribal Council and the Tetlit Gwich’in Renewable Resource Council are partners on the project. Institutional support from these organizations enables staffing several community members as research partners on the project team. Based on community and forum feedback, the following communication plan will be implemented for the 2012/2013 year: 1. Develop a plain language pamphlet aimed at the community audience, highlighting research results from 2012 – This will be distributed at the Regional Renewable Resource Committee and Gwich’in Renewable Resource Board meetings. 2. Targeting reporting activities towards existing forum which bring together land and resource managers and community decision makers. Project team members will attend and communicate relevant results and indicate where project information can be obtained at the following NWT venues: The NWT Board forum training workshop(s), the NWT Board Forum, Gwich’in Renewable Resource Board meetings, Gwich’in Renewable Resource Council regional meeting, NWT Community Planning workshop and the 2013 NWT Geoscience Forum. 3. A summary of project program activities and data on disturbances, water quality and permafrost conditions exists in draft format and will be published as an open file report through the NWT Geoscience Office. The report and data will be publically accessible. Mapping products including watershed maps, disturbance, and terrain sensitivity maps will be published as open files at the NWT Geoscience office. 4. Results are being disseminated to the scientific community. Project results have already been presented at several national and international science conferences. Peer reviewed publications are in review and in preparation. The fieldwork for this study will be conducted from June 27, 2013 to October 31, 2013.