QuotePhytoextraction â€" Removing Toxins from the Soil using Plants
Lead from outdoor based paint can end up in your soil or sandbox. Is there a way to remove lead from soil? One way being investigated to fulfill this role is phytoextraction. Phytoextraction is the use of plants to clean-up contaminants from soils, sediments, or water.1
So, how does it work?
The plants absorb contaminants through the roots and carry them up into the stems or leaves; leaving less of the contaminants in the soil after the plant has been harvested2. If there are still some heavy metals in the soil after the first round, the cycle can be repeated until the levels are minimized. An interesting tidbit is that the impurities that wind up in the plant are concentrated into a much smaller volume in the plant than was in the soil initially3.
There are two types of phytoextraction that have been studied. The first is using plants that naturally accumulate impurities from the soil and the second consists of adding EDTA or another chelating agent to assist in absorbing the contaminants from the soil.
....
Scientific research supports the use of sunflowers as a way to remove lead from the soil19 20. In fact sunflower, Indian mustard, tobacco, rye, spinach, and corn have been studied for their ability to remove lead from water, with sunflower having the greatest ability. In one study, after only one hour of treatment, sunflowers reduced lead concentrations significantly21. In addition, a DaimlerChrysler factory used Sunflowers and mustard plants to clean up 10 years worth of lead accumulation in their soil. Within a year, 25% of the toxin had been removed using the phytoextraction, saving the company $1 million in clean up costs.
more:
http://www.bluedominoes.com/content/phytoextraction-%E2%80%93-removing-toxins-soil-using-plants
QuoteOne of the most striking tests took place in 1995 in a small pond within sight of the Chernobyl nuclear power plants in Ukraine, where sunflowers were grown on Styrofoam rafts with their roots dangling in the water. The pond, like everything for miles around, was contaminated with Strontium 90, Cesium 137 and other harmful radioactive substances released during the reactor fire in 1986. Within days, the sunflowers, which have dense mops of roots, accumulated levels of cesium and strontium that were several thousand times as high as the concentrations in the water." Phytoremediation has grown mostly in the heavy metal department; one great success in this department was in Detroit in 2000. Edenspace, a phytoremediation company cleaned-up a lead contaminated area in a Daimler Chrysler building complex. The site was treated with sunflowers and Indian mustard, and lead concentrations were brought down to forty-three percent, within legal limit, for 900,000 dollars. This is about one million dollars cheaper than the traditional method of moving the soil to a hazardous waste landfill.
http://ourgreenhope.com/Current%20Projects%20and%20News.html
If a person were to plant flowers now, by the time the EPA gets its new testing procedure figured out, and the city gets around to testing, the lead may be reduced to acceptable levels.
sheclown................go for it! If you guys wait until the City does their testing and EPA figures out what and how they need to do their part..................hell will have frozen over so just do it!
Stephen, you know a great deal about Photoextraction. Your enthusiasm for bioremediation ... is contagious.
Quote(Bioremediation can be defined as any process that uses microorganisms, fungi, green plants or their enzymes to return the natural environment altered by contaminants to its original condition.)
http://en.wikipedia.org/wiki/Bioremediation
Deadgirls, you've been looking into this...what are your ideas?
QuoteAnyone Can Grow Sunflowers!
By Brenda Hyde
Sunflowers are easy, and inexpensive to grow, and yes, everyone can do it! The days of sunflowers being contained to the vegetable garden are over. There are now varieties that can be grown in large pots and containers, as well as corners of your yard or garden. Children of all ages love sunflowers and can participate in choosing the variety, planting and harvesting.
The Basics
These are the basic technical tips you need to know about Sunflowers, or Helianthus Annus (their official name).
*Plant in full sun, where they will not shade other plants.
*Be sure to plant after the last frost in your area.
*The seeds
should be 1 inch deep and 6 inches apart when planted.
*When the seedlings pop up, thin them to 1 1/2 foot apart or one foot for the dwarf varieties. (In containers you can squeeze them closer) We planted seeds in our porch box of the drawf varieties and thinned to 8 plants in a 3 foot long planter.
*Water well after planting and keep fairly moist until the seeds sprout.
more: http://oldfashionedliving.com/sunflowers.html
http://www.americanmeadows.com/FlowerSeedPackets/SpecialOccasionMiniPackets/SunflowerMini_packets.aspx?gclid=COf5v_uWxaECFQ0hnAodSFYW-A
Wikipedia's list of hyperaccumulators: http://en.wikipedia.org/wiki/List_of_hyperaccumulators
I'm going to order some sunflower seeds. If anyone else is interested in ordering, PM me and let me know. It will save on shipping and handling costs if we do this together.
Plants are amazing things, aren't they? :)
This is exactly what I use in my saltwater aquariums to filter the water: nutrient export. Mangroves, macroalgaes and even algae itself are all great for removing additives, nitrates and chemicals from water.
In case anyone that's reading this is interested in having a saltwater tank, and thought they couldn't afford it because of all the equipment... well, that's the secret to doing it cheap. And green :)
I look forward to seeing Sunflowers being planted all over the place! ;)
Sunflowers are magnificent -- so kind to us humans.
I've ordered sunflower seeds -- I will be handing out free seeds with the purchase of an item at the thrift store! I'll let you know when they arrive.
Question about sunflowers and photo extraction. What happens to the pollutant once it has been absorbed by the plant? Is the plant now contaminated? Does it need to be properly disposed of after its life cycle?
My sunflowers at the Springfield Community Garden are HUGE (taller than me!) and getting ready to flower!
Thanks for the info. This seems very important. Well meaning folks might improperly dispose of contaminated plants and unknowingly spread the problem rather than remediate it. I would suggest those that are going to use sunflowers or other plants to clean their properties of contaminants be fully aware of how to properly dispose of the dead plants...
oh great now another problem....i just rip my up and mow over them when they are dead....guess that defeats the purpose.
Thanks Stephen, and we need to be aware not only when we are "harvesting" the sunflowers, but the realities of dealing with our soil in general. Always wear gloves, put on one of those darling gardening smocks (have something that would work at the thrift store, btw), use something as a kneeler, and wash your hands when you are done. It might even be a good idea to adopt the Japanese practice of shoe removal upon entering your home (especially if you have crawling children).
I know a thing or two about lead -- I had my lead abatement and lead inspection license from EPA once upon a time.
On a side note, pets can be contaminated as well. In fact, back in 1990 when the EPA was trying to get lead legislation passed, (passed in 1992 Title X) Bush's dog got sick with lead poisoning. It made passage of the legislation easier.
Keep the gardening clothes and equipment outside of your home. Be clean, and be careful especially with raw and dusty dirt.