Bio–Monitoring

When the West Central Airshed Zone was first established, stakeholders identified the effects of ambient air quality on vegetation as an important issue.  Two of the main air quality issues identified by the public in the West Central zone were soil acidification and vegetative changes to agricultural crops and forests.  To address the question of the vegetative effects of air quality a bio-monitoring program was developed to measure growth and yield, and to document visible symptoms of coincident air quality effects in representative indicator crops.

Alfalfa (Medicago sativa L.) and saskatoons (Amelanchier alnifolia) were selected as indicator species for growth and yield qualities.  Both are sensitive to air quality and are grown commercially in the WCAS zone.

The WCAS's bio-monitoring program is a joint venture partnership with the Canadian Forest Service (CFS) and was established in 1997.  Beginning in 2000 the program changed to a 5-year re-measurement period from a previous annual assessment.  This was in keeping with the schedule for the entire Acid Rain National Early Warning System of plots.  The Hightower and Steeper sites were visited in 1999 where the condition of trees had not changed since the plots were established.  The vast majority of trees were in a healthy condition with no evidence of air pollutant stress.