© 1989 by Institute of Chartered Foresters
The Continuing Effects of Aluminium Smelter Emissions on Coniferous Forest Growth
Reid, Collins and Associates Limited 401 West Georgia Street, Vancouver, British Columbia, V6B 5A1 Canada
Industrial emissions have a detrimental effect on forests. The effects of an isolated aluminium smelter's emissions, particularly fluoride, upon the surrounding coniferous forest is suggested as the most likely cause for the measured decrease in growth.
Permanent sample plots were established in 1974 in three intensities of fume - inner, outer and surround and in a control area. They were remeasured in 1979 and 1984. Increment cores were collected from sample trees. Annual ring width and density were measured with an X-ray densitometer. Tree growth prior to establishment of the smelter in 1954 provided another control. The growth reduction was quantified per unit area, extended to estimate the total loss of growth for the whole forest and its value appraised. The estimated volumes lost were 2800 m3y–1 for the period 1954–73, 920m3y–1 1974–78 and 753m3y–1, 1979–83. The value of wood lost in the last period, 1979–83, was $13,750. At the lowest level of fumigation, the emissions appear to have a stimulating effect on forest growth.