Base de données de recherche des TNO

Régions: Gwich'in Settlement Area, Sahtu Settlement Area, Dehcho Region

étiquettes: physical sciences, climate change, greenhouse gases, environmental change, carbon, atmospheric pollution

Objectif(s): To map and assess changes in the distribution and composition of forest and peatland ecosystems due to climate changes, to estimates carbon storage (and variation) in boreal to arctic ecoregions of the Mackenzie valley and to assess interannual and seasonal variations and key processes controlling carbon dioxide and methane dynamics.

Description du projet: The objectives of this research project are to: 1. map and assess changes in the distribution and composition of forest and peatland ecosystems due to climate changes; 2. estimate carbon storage (and variation) in boreal to arctic ecoregions of the Mackenzie valley; and 3. assess interannual and seasonal variations and key processes controlling carbon dioxide (CO2) and methane (CH4) dynamics. Greenhouse gases such as CO2 and CH4 are produced in the soil and escape from the soil surface in the air, adding to global warming. Gas production from the bogs and forest soils are monitored through the year using a variety of methods. Surface emissions are being measured by collecting gas samples from the surface gas chambers, attached to a permanent base on the soil surface, at pre-determined time periods, such as 10, 20 and 40 minutes. This permits the calculation of how much gas was produced during this time from the soil. Depth of soil concentrations of greenhouse gases are being measured using metal tubes, inserted to depths of 10, 20, 30 and 50 cm in the soil; the gas, or soil water, is collected in syringes and analysed using infrared sensors to determine the amount of CH4 and CO2 in it. The system will also monitor the response of ecosystem (soil moisture, vegetation, chemistry) to changing external conditions such as precipitation, temperature extremes and permafrost thawing. Additional instruments may be installed at one or two of the new sites during the summer of 2011. These additional instruments will allow for continuous monitoring of the greenhouse gas exchange between CH4, and possibly CO2, on a location in the Deh Cho region. They will also allow for measurement of ground surface gas flux and ground water CH4 content to understand regional variation in CH4 production by bogs experiencing permafrost thaw. Through the collaboration with GNWT northern scientists technicians and students will be involved in the study. As well the communities that these regional offices interact with will be contacted and updated on the project activities. The research team has produced a small poster describing the study for distribution to local schools and community groups. A number of Government of Northwest Territories employees from regional offices have been directly involved in fieldwork to provide northern technical people with an opportunity to maintain and improve their terrestrial ecosystem ecological survey and study skills. Highlights of field and experimental work will be communicated to Northern communities through collaboration with the GNWT. Additional mechanisms for technology transfer to northern communities (through workshops, conferences, and seminars) will also be used as opportunities and needs arise. The researchers have coordinated with local schools to arrange for in class presentations and made an effort to organize site tours. The fieldwork for this study will be conducted from July 11, 2011 to September 16, 2011.