A variable F-factor to explain changes in base cation concentrations as a function of strong acid deposition

Summary

The changes in base cation production due to changes in sulfate concentrations in lakes are a function of the initial concentrations of base cations. At low concentrations of base cations, F approaches 0 and it equals 1 for areas with thick, well-drained soils or with calcareous bedrock and soils. A variable F factor has been used to explain the dependence of F on base cation concentrations and is suggested for use in making predictions of changes in strong acid concentrations in lakes following changes in deposition. Because concentrations of base cations vary from site to site and region to region, estimates of F should be site-specific. Using the variable F-factor, predictions can be made of lake acidification and recovery that yield reasonable results.

Although the research described in this article has been funded in part by a U.S. Environmental Protection Agency through Cooperative Agreement CR-810652-0102 to DFB, it has not been subjected to the Agency's review and therefore does not necessarily reflect the views of the Agency, and no official endorsement should be inferred. We thank Marella Brakke for helpful comments on the manuscript.