MAGIC (Model of Acidification of Groundwaters In Catchments) is a long
-term process-oriented model for soil and water acidification. The mod
el consists of a set of chemical equilibria between soil and soil solu
tion and an accounting of annual fluxes and pools of major anions and
cations in the ecosystem. MAGIC was applied to the dataset from the 10
5-year-old Norway spruce stand at Selling, central Germany. The primar
y aim was to evaluate the relative roles of forest management and acid
deposition on soil acidification as expressed by the pool of exchange
able base cations (base saturation). Future scenarios of management an
d deposition reduction were investigated, and the model indicated that
with a 75% reduction in deposition, soils would recover with respect
to present day values if the forest is left, or removed and converted
to grassland, but would continue to acidify if the forest was removed
and replanted.