Lichens as Bioindicators of Urban Airborne Pollutants

Overview

Topic status: We're looking for students to study this topic.

This project will study the distribution and concentrations of metals and human-derived semi-volatile organic compounds in lichens to assess their potential as bio-indicators of air quality in the Brisbane region. Lichens are symbiotic communities betwa fungus and algae commonly found on well-lit surfaces in the environment on trees androcks. They are long-lived and have been used previously to assess levels of airborne pollutants as they are presumed to concentrate such pollutants in cell materials during growth and metabolism. In this study, we will identify sites harbouring identical or similichen communities at increasing distances from the Brisbane Central Business District (CBD). Quantitative samples of each lichen will be analysed for a suite of metals and synthetic semi-volatile organic compounds. Results will be compared with regards to pollutants concentrations and distributions, concentration factors estimated from existing EPA air monitoring data, and an assessment made whether lichens act as suitable bioindicators of metal and/or semi-volatile pollutants in this subtropical coastal environment.

Aims:

  • Determine concentrations of metals and semi-volatiles in selected lichen communities surrounding Brisbane at increasing distances from urban development
  • Assess whether data from above indicate lichens as effective bio-indicators of urban-derived airborne pollution and estimate concentration factors.

In consultation with Brisbane botanic garden lichenologist, select two lichen thallus types widely distributed on substrates in the Brisbane area. Field sampling sites will be selected using a combination of abundance and increasing distance using GIS-coordinates. Samples will be taken at each site during two sampling events determined from prevailing wind direction (generally Oct-May, June-Sept.) Samples will be digested for metals and analysed using ICP-OES, semi-volatiles will be extracted and samples analysusing GC-MS. Results will be reported on a dry-weight basis and mapped. A correlation analysis between data routinely collected by QLD EPA Air Science will be performed to estimate concentration factors and evaluate the suitability of lichens as bioindicators of airborne metals and semi-volatiles in this environment.

References:

  1. Conti, M.E. and Cecchetti, G. 2001. Biological monitoring: lichens as bioindicators of air pollution assessment-a review. Environ Pollut 114:471-492.
  2. Szczepaniak, K. and Biziuk, M. 2003. Aspects of the biomonitoring studies using mosses and lichens as indicators of metal pollution. Envron. Res. 93:221-230.
Study level
Honours
Supervisors
QUT
Organisational unit

Science and Engineering Faculty

Research area

Biogeoscience

Contact

Please contact the supervisor.