Research projects that have similar overall objectives to those sponsored by the Midwest HSRC are listed below.

PIs: M. K. Banks, J. A. Alleman, and A. P. Schwab
Funded by the Indiana Department of Transportation

View the detailed project abstract by clicking here.

Metal Removal Capabilities of Passive Bioreactor Systems: Effects of Organic Matter and Microbial Population Dynamics
For more inormation, visit the Rocky Mountain Regional HSRC at http://www.engr.colostate.edu/hsrc/.

Phytoremediation in Wetlands and Confined Disposal Facilities
For more inormation, visit the South and Southwest HSRC at
http://www.hsrc-ssw.org/sswphyto.html.

Ecolosystem Monitoring Via Genetic Diversity Surveys of Dandelions using VNTR Multilocus DNA Probes

Progress Report: October 11, 2001.
EPA Agreement Number: R826602-01-0.
Title: Ecolosystem Monitoring Via Genetic Diversity Surveys of Dandelions using VNTR Multilocus DNA Probes.
Investigators: Steven Rogstad and Brian Keane.
Institution: Department of Biological Sciences ML6, University of Cincinnati, Cincinnati, OH 45221-0006.
Research Category: Ecological Indicators.
Project Period: August, 1998 through July, 2002.

Excerpts from the October 11, 2001 progress report:

Objectives of the Research Project:

New methodologies in molecular genetics may provide novel types of ecological indicators for monitoring the integrity of natural ecosystems and the sustainability of ecosystems that are affected by anthropogenic influences. One type of ideal ecological indicator would be an organism that grows in a wide variety of habitats that could easily be used to monitor for the presence of mutagens or anthropogenic factors that alter normal population genetics processes. We are investigating dandelions (Taraxacum officinale Weber; Asteraceae) as a potential model ecological indicator organism because: 1) dandelions have an extremely wide ecological amplitude, growing almost worldwide from sea-level to alpine biomes, and from the tropics to north-temperate habitats; 2) dandelions grow rapidly, and populations can be easily manipulated and monitored; 3) it has been documented that a variety of pollutants can be sequestered in dandelion tissues; 4) dandelion seeds are produced asexually rendering the detection of mutations easy; and 5) we have generated preliminary data using variable-number-tandem-repeat (VNTR) DNA probes (used in DNA fingerprinting) that suggest that mutation rates and population genetic diversity parameters can be analyzed successfully with dandelions. The specific hypothesis to be tested is: dandelions can be used as a sensitive ecological indicator species through comparative analyses of VNTR genetic markers since differences in 1) mutation rates, and/or 2) population genetic structure, can be detected between pollution impacted versus non-impacted populations.

Research Conclusions to Date:

Excepting the data that are already published (see list below), the above is a preliminary description of our major results to date. If the above trends hold, we will conclude the following:

a) PM10 is a good indicator of the degree of soil contamination for the metals examined;

b) dandelions are not effective biomonitors in the sense that their tissues sequester metals in proportion to the concentration of metals in the soil, except perhaps for extremely polluted sites as described by previous authors;

c) dandelions may be good ecosystem biomonitors in the sense that they reflect metal bioavailability, that is, how the plant population at a site is interacting with the metals to sequester them;

d) there is abundant genetic diversity of clones of dandelions, with some very widespread, common clones, with other clones being perhaps less common and more limited in distribution;

e) seed dispersal is extremely effective in distributing the clones, with measures of diversity being essentially the same for small (600 m length), medium (30 km length), and large (330 km length) transects;

f) dandelions thus far appear to be good mutation stressor biomonitors, indicating that as the tissue exposure to four metals, or possibly other, related mutagen stressors, increases, mutation rates at a site increase;

e) while dandelion dispersal of clones appears to be very effective, the metals at a site (or related factors) can select for dandelions that differ in response to metal presence;

and f) there are costs associated with being dandelion clones that are either pollution intolerant or tolerant.