DECREASED TRANSPIRATION IN POLAR TREES EXPOSED TO 2,4,6-TRINITROTOLUENE

This article discusses the effects of various concentrations of the ex plosive 2,4,6-trinitrotoluene (TNT) on the transpiration of hybrid pop lar trees growing in hydroponic media. Transpiration was measured dail y by gravimetric means. The rapid removal of TNT from hydroponic solut ions was a result of plant uptake and required a daily dosage of TNT i o ensure a relatively constant exposure over lime. Transpiration decre ased with increasing TNT concentrations greater than or equal to 5 mg/ L. Decreases in transpiration were accompanied by leaf chlorosis and a bscission. A comparison between a laboratory study and a pilot-scale e xperiment showed good scale-up potential.