Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Tumbleweeds good for uranium clean-up

05.11.2004


The lowly, ill-regarded tumbleweed might be good for something after all.



A preliminary study reveals that tumbleweeds, a.k.a. Russian thistle, and some other weeds common to dry Western lands have a knack for soaking up depleted uranium from contaminated soils at weapons testing grounds and battlefields. "There is some use to what we consider noxious weeds," said geologist Dana Ulmer-Scholle of the New Mexico Institute of Mining and Technology in Socorro.

Depleted uranium (DU) is used in armor-piercing munitions. Although it produces only a low level of radiation, the metal poses a hazard in soils because it – like some other heavy metals – is toxic if ingested. Other plants have been known to draw out DU from soils in wetter climes "but no one wanted to try doing it in arid regions," said Ulmer-Scholle.


Ulmer-Scholle’s work is underwritten by the US Department of Defense, which is looking for innovative, cost-effective, and efficient ways of cleaning up soils at weapons testing areas and battlefields where DU has been used. Ulmer-Scholle will be presenting the promising results of tumbleweeds and other weeds in arid lands on 10 November at the annual meeting of the Geological Society of America in Denver.

In her study, Ulmer-Scholle and her colleagues Bonnie Frey, Terry Thomas, and Michael Blaylock first sought out DU contaminated soils at an inactive munitions testing ground in New Mexico. Then they planted selected native and non-native plants in a test garden and in pots to see how much DU the plants absorbed from the soil.

Among the plants that sucked up lots of DU was Indian mustard (Brassica juncea), she reports. But that plant it is not well suited to deserts and needed irrigation. Better adapted to the dry environs, she said, were Russian thistle (Salsola tragus), the grain crop quinoa (Chenopodium quinoa) and purple amaranth (Amaranthus blitum). "Our goal is to use plants with the least amount of water and the minimum amount of care," said Ulmer-Scholle. They also found that sprinkling the ground with citric acid enhanced the plants’ ability to absorb DU.

Russian thistle is a non-native plant to North America and is considered a nuisance in most parts of the western US. It springs up almost anywhere soils have been disturbed and each plant scatters its hundreds of seeds by detaching from its roots and tumbling along the ground in the wind.

Using tumbleweeds and other unpopular plants for DU clean-up needn’t spread noxious weeds either, Ulmer-Scholle explained. It turns out that the plants tested do their best DU absorbing before they flower and long before they set seeds. So part of the trick to using weeds to clean up DU is to harvest the plants before they flower, she said.

The fact that plants absorb uranium is not news, since old uranium prospectors used to use Geiger counters on junipers to find buried uranium lodes. But finding a plant that grows fast on little water and can be easily harvested to carry away the depleted uranium – that’s another story. "We tried it here (in Southern New Mexico) and also in a natural uranium mine site in northern New Mexico," she said. The weeds picked up even more uranium in more contaminated soils. "So we got more where there was more in the soils."

As for why some plants absorb uranium, that’s still a mystery, says Ulmer-Scholle. It could be that the plants use the metal to create pigments. One way she hopes to test that possibility is to grow native plants used for dyes, she said.

Phytoremediation of Depleted Uranium in an Arid Environment
Environmental Geosciences, Poster Session II
Wednesday, 10 November, 1:30 -5:30 p.m., CCC
Exhibit Hall

Ann Cairns | EurekAlert!
Further information:
http://www.geosociety.org

More articles from Earth Sciences:

nachricht NASA examines Peru's deadly rainfall
24.03.2017 | NASA/Goddard Space Flight Center

nachricht Steep rise of the Bernese Alps
24.03.2017 | Universität Bern

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Argon is not the 'dope' for metallic hydrogen

24.03.2017 | Materials Sciences

Astronomers find unexpected, dust-obscured star formation in distant galaxy

24.03.2017 | Physics and Astronomy

Gravitational wave kicks monster black hole out of galactic core

24.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>