Abstract |
The authors have evaluated atmospheric deposition related geochemical changes in New England and Quebec by means of (1) transect studies of soil chemistry parallel to pH and metal deposition gradients: and (2) chemical analysis of lake sediments with the following results: (a) Mn, Ca, Mg, K, Zn, Fe, and Pb concentrations and pH in organic litter of high altitude spruce-fir forests relate to the present pH gradients for precipitation and inferred gradients of heavy metal loading; atmospheric deposition of heavy metals (including Pb, Zn, and Cu) began increasing in the 19th century in New England and may be leveling out in the last 5-10 years. Results imply that increasing atmospheric deposition of acids and metals has strongly influenced forest soils, sediment, and surface water chemistry. |