Deposition Monitoring & Mapping
To better understand the nature and quantity of the compounds deposited on the regional landscape, the WBEA operates a network of air quality and deposition monitoring sites in remote locations across the Wood Buffalo region. Various technologies are employed in the network:
- Passive air sampling uses a permeative or diffusive membrane, allowing for the physical uptake of gas or vapour sample. Chemical species monitored by passive methods include ammonia (NH3), nitric acid (HNO3), nitrogen dioxide (NO2), ozone (O3), and sulphur dioxide (SO2). Data obtained from passive air sampling is used to model deposition trends across the region.
- Active air sampling uses a pump to provide a known volume of air to a continuous analyzer or sample media. In remote areas, absent from grid-supplied power, active sampling is achieved using solar powered systems. Ammonia (NH3), nitric acid (HNO3), and particulate matter (PM2.5) are monitored year-round by active sampling with filter media. Ground-level ozone (O3) is monitored April through October by active sampling with continuous analyzers.
- Passive deposition sampling is achieved through ion exchange resin technology. A column of resin beads is affixed to precipitation collectors to capture charged chemical species (ions) in precipitation water. Chemical species monitored by ion exchange resin include ammonium (NH4+), nitrate (NO3-), phosphate (PO43-), sulfate (SO42-), and base cations (Ca+, K+, Mg+, Na+).
Instrumented towers provide continuous measurements of regional meteorological conditions at six TEEM Forest Health Monitoring sites. These data are necessary for proper interpretation of air quality and ecological monitoring data and can be downloaded on each Monitoring Station page.
Conditional Time Averaged Gradient:
Conditional time averaged gradient (CoTAG) technique has been used to measure deposition velocities of compounds containing nitrogen and sulphur. Results are used to calibrate deposition models and estimate dry deposition.
Stable isotope signatures have been used to determine whether a link between specific natural and anthropogenic emission sources and deposition at TEEM sites can be made. Stable isotopes can also be used to trace the fate of these emissions in the terrestrial environment.