Rhizosphere microbial and enzyme assays as indicators of the extent of TNT phytoremediation in soil.
(S11-chekol751543-oral)
Authors:
T. Chekol* - Battelle Memorial Institute
Abstract:
The primary objective of this study was evaluation of the role of rhizosphere biological activity in phytoremediation of trinitrotoluene (TNT) contaminated soils. Two plant species, reed canarygrass (Phalaris arundinacea L.), switchgrass (Panicum variegatum L.), were used for the planted component of this study. The results of this experiment showed that more than 87% of the initial TNT was
recovered from the non-planted control soils, while only 32% or less was recovered from planted pots.
Presence of plants significantly increased the soil biological activity (microbial counts and rhizosphere dehydrogenase and TNT-nitroreductase activities) and this greater rhizosphere enzyme activity was closely related to a higher level of TNT transformation. Moreover, soil biological activity (microbial counts and rhizosphere TNT-nitroreductase and dehydrogenase activities) was higher in switchgrass planted soils compared to those planted with reed canarygrass. Soil TNT levels at the end of
experiment were 1-4% lower in switchgrass planted soils when compared to those in the reed
canarygrass planted soils. The data suggested that higher soil biological activity was responsible for the lower soil TNT levels in the planted soils compared to unplanted controls and switchgrass planted soil compared to reed canarygrass planted soils. These results showed that rhizosphere microbial and enzyme assays could be used as indicators of the extent of TNT phytoremediation in soil.
Speaker Information: Tesema Chekol, Battelle Memorial Institute, Battelle Eastern Science and Technology Center 12, Aberdeen, MD 21001-1228, MD 21001; Phone: 410-306-8641; E-mail:
Session Information: Tuesday, November 4, 2003, 1:25 PM-3:45 PM Presentation Start: 3:00 PM
Keywords: Rhizosphere microbes,; enzymes,; phytoremediation; TNT