SULPHUR AND BORON ISOTOPE VARIATIONS TO TRACK AIR POLLUTANT DEPOSITION IN THE CASTLE RIVER OF SOUTHERN ALBERTA, CANADA

摘要

Alberta is rich in fossil fuels. Oil and natural gas industries are major economic contributors to this province. However, as fossil fuel industries expand, gaseous emissions rapidly increase. Since these emissions often contain greenhouse gases like CO2 and amounts of poisonous and corrosive gases such as H2S, SO_x and NO_x, the emissions not only acidify precipitation and contaminate the environment, but could cause serious injury to human health. Thus, it is particularly important to study and understand the source of industrial emissions, the transformation of aerosols in atmosphere, and the deposition to the surrounding areas. The study area is located in southwestern Alberta and encompasses the headwaters of the Castle River watershed. This region is situated along the eastern slopes of the Rocky Mountains between the Crowsnest Pass and Waterton Lakes National Park. This area is characterized by strong prevailing southwest and westerly winds. The Castle River originates at the upper boundary of Waterton Lakes National Park, flows from south to north and eventually joins with the Oldman River as it is part of the Oldman River Basin (Figure 1). In order to successfully track the origin of pollution and understand aerosol deposition variations in the Castle River watershed, an effective tracing method employing stable isotope abundance data was applied.