Potential remediation of 137Cs and 90Sr contaminated soil by accumulation in Alamo switchgrass

Entry, James A. and Watrud, Lidia S. (1998) Potential remediation of 137Cs and 90Sr contaminated soil by accumulation in Alamo switchgrass. Water, Air, and Soil Pollution. 104:339-352.

PDF 986.pdf Download (567kB)

Abstract

Cesium-137 ( 137Cs) and Strontium-90 ( 90Sr) are radionuclides characteristic of nuclear
fallout from nuclear weapons testing and nuclear reactor accidents. Alamo switchgrass (Panicum
virginatum L.) is a perennial C4 species native to central North America that produces exceptionally
high biomass yields in short periods of time. In three separate experiments, Alamo switchgrass plants
were tested for their ability to accumulate 137 Cs and 90 Sr from a contaminated growth medium.
Plants in experiment I were grown in 33 x 20 x 7 cm plastic pans containing 2.5 kg sand. Plants
in experiments 2 and 3 were grown in 30 x 3 cm diameter test tubes containing 0.3 kg growth
medium. After 3 months of plant growth, either 102 Bq 137 Cs or 73 Bq 90Sr g-1 soil were added
to the growth medium. Plants in all three experiments were grown within a greenhouse that was
maintained at 22 ± 2 °C with a photosynthetic active radiation of 400-700 umol m-2 s-1 and
a 14-16 h photoperiod. Above-ground plant biomass did not differ between plants that were not
exposed to these radionuclides (controls) and those that were exposed to growth medium containing
137Cs or 90Sr over the course of the experiment. Plants accumulated 44 and 36% of the total amount
of 90Sr and 137CS added to growth medium after the first 5 harvests. After the first two harvests, the
concentration of 137CS and 90Sr in plant tissue and the amount of 137Cs or 90Sr removed from growth
medium declined with each successive harvest. Duration of exposure correlated curvilinearly with
accumulation of both 90Sr and 137CS by plants (r2 = 0.95 and 0.78, respectively). As concentration of
both 137Cs and 90Sr in growth medium increased, plant accumulation of both radionuclides increased
and correlated curvilinearly in seedlings (r2 = 0.83 and 0.89 respectively).

Item Type:	Article
NWISRL Publication Number:	0986
Subjects:	Irrigated crops > Grass forage Mass Import - autoclassified (may be erroneous)
Depositing User:	Dan Stieneke
Date Deposited:	20 Nov 2010 21:54
Last Modified:	17 Nov 2016 16:00
Item ID:	712
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/712