| Abstrakt: |
Foliage from each of four hardwood species—white birch (Betula papyriferaMarsh.), red oak (Quercus rubraL.), red maple (Acer rubrumL.), and trembling aspen (Populus tremuloidesMichx.)—growing on sites severely and moderately damaged by fumes and dustfall and on control sites near Sudbury, Ontario, and soil from beneath the trees were sampled and analyzed for various chemical constituents. Results indicated that on sites damaged by fumes and dustfall, soils were impoverished with respect to organic matter content, exchangeable bases (particularly Ca and Mg), and trace elements (particularly Mn and Zn). Levels of S, Fe, Cu, and Ni were also increased. Foliage analysis provided additional support for the proposition that soils contained near toxic to toxic levels of Ni and Cu. If conditions improve, however, with respect to suppression of Ni or Cu supply, tree growth could be limited by the availability of Ca, Mg, or Mn, or even of N or P. |
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