SULFUR GAS EMISSIONS IN THE BOREAL FOREST - THE WEST WHITECOURT CASE-STUDY .8. PINE TREE MINERAL-NUTRITION

Nutrient analyses of foliage from a naturally occurring hybrid of Pinus contorta Loud. and P. banksiana Lamb. (lodgepole pine × jack pine), were used to determine if chronic exposure to S gas emissions had affected the nutrient status of the trees. This study was part of a larger case study investigating the effects of 17 yr of exposure to S gas emissions from a S-recovery gas plant on a forest ecosystem in west central Alberta, Canada. Significant inverse, linear relationships were found between foliar sulphate-S levels and distance from the S source in all three age classes of pine foliage tested. Sulphate-S levels increased with increasing age of foliage at sites near the source while they decreased with increasing age of foliage at sites not frequently exposed to the S gas emissions. Soil pH was reduced in the top 5 cm of soil at sites near the source and elevated contents of total S in the soil were also found at those sites. Manganese concentrations in foliage from the sites near the source were significantly higher than in foliage from sites away from the source. The level of Mn also increased with increasing age of tissues. The elevated level of sulphate-S in foliage and lower soil pH at sites near the source indicated significant amounts of S from the source had been deposited at those sites. The lower soil pH most likely contributed to the increased availability of Mn that was found in the foliage. © 1990 Kluwer Academic Publishers.