Ja. Entry et al., Influence of organic amendments on the accumulation of Cs-137 and Sr-90 from contaminated soil by three grass species, WATER A S P, 126(3-4), 2001, pp. 385-398
Bahia grass (Paspalum notatum), johnson grass (Sorghum halpense) and switch
grass (Panicum virginatum) were compared for their ability to accumulate Cs
-137 and Sr-90 from three different contaminated soils in the presence and
absence of either sphagnum peat or poultry litter amendments. Above-ground
plant biomass did not differ between plants that were not exposed to these
radionuclides and those that were exposed to soil containing Cs-137 or Sr-9
0. After three harvests, bahia, johnson and switchgrass plants accumulated
from 17.2 to 67.3% of the Cs-137 and from 25.1 to 61.7% of the Sr-90 added
to the soil. Poultry litter and peat moss amendments increased aboveground
plant biomass, activity of Cs-137 or (9)0Sr in plant tissue, % accumulation
of Cs-137 or Sr-90 from soil and the plant bioconcentration ratio at each
harvest compared to the control (no amendment) treatment. The greatest incr
eases in plant biomass, and radionuclide accumulation were observed with po
ultry litter for each of the three grass species. Johnson grass had greater
aboveground plant biomass, activity of Cs-137 and Sr-90 in plant tissue, %
accumulation of Cs-137 or Sr-90 from soil and bioconcentration ratio in ea
ch soil amendment, at each harvest compared to bahia and switchgrass. The g
reatest accumulation of Cs-137 and Sr-90 was measured in johnson grass grow
n in soil that was amended with poultry litter. These results suggest that
plant species selection and agronomic practices may need to be considered t
o maximize phytoremediation of radionuclide contaminated soils.