NWT RESEARCH DATABASE

Tags: physical sciences, geology, climatology, greenhouse gases, atmospheric sciences, carbon fluxes, tundra ecosystems

Objective(s): The objectives of this research are 1) to measure how important greenhouse gases, carbon dioxide and methane, are exchanged between tundra surfaces and the atmosphere; 2) relate them to environmental variables such as soil properties and weather.

Project Description: This licence is being issued for the scientific research application no. 947. The objectives of this research are 1) to measure how important greenhouse gases, carbon dioxide and methane, are exchanged between tundra surfaces and the atmosphere; 2) relate them to environmental variables such as soil properties and weather. This is all in hopes of understanding more about how future climate change will impact the land surface and how these impacts might influence the climate itself. This research is part of a long-term study of tundra-atmosphere interactions at Daring Lake. The primary platform for measuring the CO2 exchange is eddy covariance towers, which the researchers have established for the past several summers at an upland tundra site and in a wet sedge fen, and occasionally at a shrub site. The tower equipment runs automatically and is visited a few times a week for data retrieval and maintenance. Daily (or weekly) measurements to vegetation growth and active layer depth are made around the sites. There is no disturbance of the surrounding tundra. As well, the researchers measure CO2 from small (0.5 x 0.5 m) plots on various tundra communities using a manual chamber system. These measurements help them to understand how the small-scale heterogeneity of the tundra vegetation influences the tower measurements. The researchers will also be measuring methane (CH4) exchange at various sites using the chamber technique, and new for 2009, will be the addition of equipment to the fen eddy flux tower to measure ecosystem-scale CH4 fluxes. The additional equipment will not introduce any new disturbance to the tundra. Some vegetation sampling is required at the experimental plots. Plots (5 per location) are manipulated by clipping the vegetation in order to measure the soil only component of the flux and to measure total biomass and leaf area index. These measurements are conducted weekly and confined to small patches of tundra not far from the towers. The measurements will take place between May and September, encompassing the summer growing period. Previous measurements indicate that various tundras at Daring Lake are a net sink for CO2 during the growing season and a loss of CH4. Measurements in 2009 and coming years will establish the variability in the size of this sink and help us to determine if it will persist as climate change occurs. Daring Lake Research Station hosts an annual 'Science Camp' for high school kids from NWT. Each year the research group assists the camp by giving demonstrations of the research and tours of the sites. Two of the members were involved with this activity in 2008 and will continue to participate in the future. Copies of any papers that result from the research will be forwarded to the Aurora Research Institute and interested communities. The fieldwork for this study will be conducted at Daring Lake Terrestrial Ecological Research Station from March 31 to September 30, 2009.