© 1986 Heron Publishing—Victoria, Canada
The electrical conductivity of Norway spruce needle diffusate as affected by certain air pollutants
Theodore Keller
Swiss Federal Institute of Forestry Research, Birmensdorf, Switzerland / Received November 25, 1985
Summary
Four-year-old potted Norway spruce (Picea abies (L.) Karst.) grafts established with scion material from three mature trees, were exposed to either long-term fumigation
with SO2, with and without water stress, or long-term ozone fumigation. The electrical conductivity of the needle diffusate was measured
after the needles had been washed with chloroform and then leached in distilled water. Although none of the treatments caused
visible symptoms of injury, SO2 fumigation and water stress both caused an increase in diffusate conductivity, but the effects were not synergistic. Ozone
fumigation lowered both conductivity and nutrient ion concentration in the leachate.
