Phytoremediation of pyrene in a Cecil soil under field conditions.
We evaluated the effects of annual ryegrass (Lolium multiflorum Lam.) and phosphorus (P) availability on the dissipation of pyrene added at a concentration of approximately 600 mg kg-1 dry soil in the top 7.5 cm of a Cecil loamy sand (fine, kaolinitic, thermic Typic Kanhapludults) in a 10-month experiment under field conditions in Clemson, South Carolina. Plastic canopies were installed to prevent flooding of plots and raindrop dispersion of pyrene. Treatment factors were pyrene, vegetation, and available P levels. Each of the eight treatments had four replicates. The soil was adjusted to low and high P concentrations (an average of 41 and 66 kg extractable P ha-1, respectively). After a 175-d lag period for all treatments, the rate of pyrene removal followed first-order kinetics. The first-order rate constant was significantly higher in nonvegetated (0.098 d-1) than vegetated treatments (0.034 d-1). These data suggest that the presence of easily biodegradable organic matter from plant roots slowed the removal rate of pyrene. The levels of available P did not affect the rate of pyrene dissipation. Pyrene decreased below the detection limit of 6.25 mg kg-1 dry soil in all treatments after 301 d.
Lalande
T L
TL
Department of Crop & Soil Environmental Science, Clemson University, Clemson, SC 29634, USA.
Skipper
H D
HD
Wolf
D C
DC
Reynolds
C M
CM
Freedman
D L
DL
Pinkerton
B W
BW
Hartel
P G
PG
Grimes
L W
LW
D001673:Biodegradation, Environmental / Q000187:drug effects; D008129:Lolium / Q000187:drug effects / Q000378:metabolism*; D010758:Phosphorus / Q000494:pharmacology; D011084:Polycyclic Aromatic Hydrocarbons / Q000378:metabolism; D011721:Pyrenes / Q000378:metabolism*; D012987:Soil / Q000032:analysis; D012989:Soil Pollutants / Q000378:metabolism*
D011084:Polycyclic Aromatic Hydrocarbons; D011721:Pyrenes; D012987:Soil; D012989:Soil Pollutants; D010758:Phosphorus; C030984:pyrene