Featured Research

from universities, journals, and other organizations

Using Plants To Clean Up Soil

Date:
January 29, 2007
Source:
USDA/Agricultural Research Service
Summary:
Raising soil acidity to a pH level of 5.8 to 6 to help alpine pennycress absorb heavy metals from soil doesn't harm beneficial soil microbes, according to a recent study by Agricultural Research Service (ARS) scientists and cooperators.

Alpine pennycress doesn't just thrive on soils contaminated with zinc and cadmium--it cleans them up by removing the excess metals.
Credit: Photo by Keith Weller

Raising soil acidity to a pH level of 5.8 to 6 to help alpine pennycress absorb heavy metals from soil doesn't harm beneficial soil microbes, according to a recent study by Agricultural Research Service (ARS) scientists and cooperators.

Related Articles


The researchers have been conducting ongoing studies on using alpine pennycress (Thlaspi caerulescens) to remove cadmium and other heavy metals as part of a soil remediation process known as phytoextraction. Previously, they found that lowering the pH helped the plant remove toxic metals, but they were concerned that increasing soil acidity too much could harm beneficial soil microbes.

ARS agronomist Rufus Chaney, with the Environmental Management and Byproduct Utilization Laboratory, Beltsville, Md., has been a leader in using metal-accumulating plants to clean contaminated soil. He and others have shown that T. caerulescens can concentrate up to about 8,000 parts per million of toxic cadmium in its leaves.

Harvesting the aboveground vegetation annually makes it possible to reduce the concentration of cadmium in soil to safe levels in three to 10 years. Phytoextraction costs about $250 to $1,000 per acre per year, while the alternative clean-up method--removal and replacement with clean soil--costs about $1 million per acre.

The University of Maryland filed a patent on the use of T. caerulescens for the phytoextraction of cadmium in 2000, with Chaney as a cooperator. A patent for the process was granted in 2006 in the United States and Australia. No other similar technologies currently exist for remediation of cadmium-contaminated soils using plants.

To measure how pH affects soil microbes, Chaney and University of Maryland colleagues Shengchun Wang and Scott Angle adjusted two smelter-contaminated, high-metals soils to a range of pH levels, grew T. caerulescens in them for six months, and then analyzed soil microbe populations and activity. Then they adjusted the soils back to normal pH levels and incubated them for six months, to see if previously observed reductions in microbes persisted under normal soil management.

The scientists found that if the soil pH was adjusted no lower than that needed to maximize annual cadmium removal--a pH of about 5.8 to 6--there was no lasting adverse effect on soil microbes. And in both test soils, T. caerulescens tended to protect the soil microbes, compared to unplanted soils at the same pH levels.

ARS is the U.S. Department of Agriculture's chief scientific research agency.


Story Source:

The above story is based on materials provided by USDA/Agricultural Research Service. Note: Materials may be edited for content and length.


Cite This Page:

USDA/Agricultural Research Service. "Using Plants To Clean Up Soil." ScienceDaily. ScienceDaily, 29 January 2007. <www.sciencedaily.com/releases/2007/01/070125114121.htm>.
USDA/Agricultural Research Service. (2007, January 29). Using Plants To Clean Up Soil. ScienceDaily. Retrieved October 25, 2014 from www.sciencedaily.com/releases/2007/01/070125114121.htm
USDA/Agricultural Research Service. "Using Plants To Clean Up Soil." ScienceDaily. www.sciencedaily.com/releases/2007/01/070125114121.htm (accessed October 25, 2014).

Share This



More Plants & Animals News

Saturday, October 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Reuters - Innovations Video Online (Oct. 24, 2014) Miniature deep sea animals discovered off the Australian coast almost three decades ago are puzzling scientists, who say the organisms have proved impossible to categorise. Academics at the Natural History of Denmark have appealed to the world scientific community for help, saying that further information on Dendrogramma enigmatica and Dendrogramma discoides could answer key evolutionary questions. Jim Drury has more. Video provided by Reuters
Powered by NewsLook.com
Black Bear Cub Goes Sunday Shopping

Black Bear Cub Goes Sunday Shopping

Reuters - Light News Video Online (Oct. 23, 2014) Price check on honey? Bear cub startles Oregon drugstore shoppers. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Dances With Wolves in China's Wild West

Dances With Wolves in China's Wild West

AFP (Oct. 23, 2014) One man is on a mission to boost the population of wolves in China's violence-wracked far west. The animal - symbol of the Uighur minority there - is under threat with a massive human resettlement program in the region. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
Breakfast Debate: To Eat Or Not To Eat?

Breakfast Debate: To Eat Or Not To Eat?

Newsy (Oct. 23, 2014) Conflicting studies published in the same week re-ignited the debate over whether we should be eating breakfast. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins