Effectiveness of Ailanthus altissima as a bioindicator of ozone pollution
Open Access
- Author:
- Seiler, Lauren Katherine
- Graduate Program:
- Ecology
- Degree:
- Master of Science
- Document Type:
- Master Thesis
- Date of Defense:
- May 30, 2012
- Committee Members:
- Dennis R Decoteau, Thesis Advisor/Co-Advisor
- Keywords:
- Ailanthus altissima
ozone
bioindicator
air pollution - Abstract:
- Ground-level ozone is one of the most significant air pollutants in the US; it is harmful to human health, vegetation, and ecosystems. Concurrently, Ailanthus altissima (tree-of-heaven, Ailanthus) is one of the most invasive plant species in the US. A series of exposure experiments and field surveys were conducted during 2010 and 2011 to evaluate the effectiveness of Ailanthus as a bioindicator of ozone pollution. To explore the uniformity of Ailanthus’ reaction to ozone, Ailanthus seedlings from 6 locations (Reno, NV; Corvallis, OR; Bloomington, IN; Mineral, VA; State College, PA; and Far Rockaway, NY) were exposed to ozone using continuously stirred tank reactor chambers within a greenhouse. Seedlings from the Corvallis, OR seed source were planted in the field and monitored for ambient ozone-induced foliar injury along with staghorn sumac, black cherry, common milkweed, and dogbane to evaluate Ailanthus’ performance compared to other ozone bioindicators. Potted Ailanthus seedlings were exposed in a greenhouse to 5 different ozone concentrations to determine if a relationship existed between concentration of ozone exposure and foliar injury. Plants from Corvallis, OR were significantly more susceptible to ozone exposure than were other seed sources (P < 0.0152). Ambient ozone levels in Pennsylvania during the growing season were sufficient to induce foliar symptoms on all surveyed flora species, including Ailanthus, in the field, and Ailanthus preformed comparably to the other bioindicators. Also, a positive linear relationship existed between ozone exposure concentration and foliar injury on Ailanthus plants (R2= 0.8543). We conclude that, aside from the variability in the germplasm, Ailanthus is an effective bioindicator of ground-level ozone pollution.