We hypothesize that enhanced acid deposition along an altitudinal gradient will unfavourably impact the lysimetric water chemistry and leach nutrients from old Calamagrostis villosa stands. A 3-year field experiment was conducted transferring soil blocks with old C. villosa swards into plastic containers modified to hold lysimeters at three different elevations (635, 940 and 1140 m a. s.l.) and characterized by different intensities of acid deposition. The chemistry of lysimetric water was mostly not significantly affected by site in individual parts of growing seasons. Nevertheless, the ANOVA revealed a significant effect of site on the concentration of Ca2+ and Al3+. Chemistry of percolates was significantly altered with time due to annual differences in acid deposition. Statistically significant positive correlations were found between nitrogen and sulphate inputs in wet depositions and acidity of lysimetric water, and the amounts of leached Ca2+ and nitrates at various parts of the growing season. Swards of C. villosa partly eliminate excess of nitrogen in soil, due to their large accumulation in plant biomass. They reduce negative processes associated with soil acidification. However, enhanced input of both nitrogen and sulphate loads can lead to increased leaching of both the nitrates and calcium, particularly at higher elevations.