Permanent grassland (with lysimeters) and arable land for maize sowing were fertilized with acidified and non-acidified cattle slurry with different doses of N. The content of minerals (C, N, P, K Mg, Ca, SH) and pH in soil samples from arable fields and lysimeters were detd. The acidified slurry did not cause any significant changes in soil pH, but it increased the yield and protein content in both grass and maize.