Using Organisms to Clean up Contaminated Soil and Groundwater
|An article in The New York Times tells how plants can be used to treat metal and organic contaminants, radioactive elements, and sewage. The article notes: "In the United States alone, the cost of decontaminating tens of thousands of toxic sites on factory grounds, farms, and military installations is expected to eventually surpass $700 billion. The main approach so far is costly and disruptive, often requiring fleets of trucks, forests of mechanical wells, and other equipment. But, after a decade of field and greenhouse tests, a variety of techniques harnessing the absorptive power of plants' roots (bioremediation) appear poised for a much expanded role."
The concept of Bioremediation is not new. For years, "Bioneers" - biological pioneers - have been installing inexpensive low-maintenance systems in countries all over the world using microbes, flowers, snails, clams, crayfish, and fishes to gobble up all manner of waste products. At last year's 1lth Bioneers Conference, Paul Stamets explained how mushrooms are among nature's creations, which can help clean up the messes we humans leave:
"I call mushroom mycelia 'Earth's natural internet.' A mushroom mycelium can have a mile of cells in a cubic inch of topsoil. These root systems digest nutrients externally. They produce acids and enzymes to de-molecularize large organic complexes such as plant fibers and animal tissue. Throughout the world, on every landmass, there are mosaics of overlapping mycelial mats coursing underfoot. The complexity of these mycelial mats is the basis of our food chain. Unless fungi recycle these nutrients, all ecological systems in the world will collapse."
In one example of the effectiveness of mycelial mats, "Because the mushroom mycelium produces enzymes that sever hydrogen-carbon bonds, I was approached by a bio-remediation company about decomposing diesel oil. The mycelium absorbs the oil and breaks down hydrocarbons, the basis of all pesticides - PCBs, PCPs, dioxins."
"In a contest in Bellingham, Washington, we were one of six companies competing to see who could break down diesel-contaminated soil. We mixed up the mushroom mycelium into the sixth pile of contaminated soil. One month later we went from pile to pile and the first five piles were dead, smelly, ugly, lifeless. We pulled the tarp away from the sixth pile, and there were oyster mushrooms, some up to 12 inches in diameter. But something even more remarkable occurred. After eight weeks, the mushrooms started to rot and they produced spores. The spores attracted insects. The flies laid eggs in the mushrooms; larvae were produced. Birds came in to eat the larvae. They brought in seeds, which began the process of phytoremediation, i.e., plants growing.
"We think we have found a keystone mechanism, based primarily on organisms which can live on dead or decaying matter that causes a domino effect which leads to repair of the ecosystem. We create the greatest debris trails of any organism on the planet and these things are running behind us trying to help, trying to repair the environment. I do think that we face an impending ecological collapse. Fifty percent of the mycorrhizal mushrooms in Europe have become extinct in the past 30 to 40 years. This is bad news because fungi can help repair the planet.
|Comments: Has widespread applicability and it actually works. It addresses the urgent need to halt ecological collapse, especially in Europe.
|Extent of Action:||National|
|Source:||Timeline #58,July/August 2001|
|Paul Stamets www.fungi.com, Bioneers http://www.bioneers.org/|
|Prepared By:||sl 11/3/01|