Effect of two applications of substrate on nitrification and pH of soils

A laboratory incubation experiment at 15 deg. C was carried out with two applications of substrate as ammonium sulfate on the measurement of ammonium disappearance, nitrate formation rates and measurement of pH of different soils at Glasgow University, Glasgow, United Kingdom during 1995. The ammonium disappearance and nitrate formation rates were not significantly different between the first and second application in neutral soils, however, a significant inhibitory effect was observed in ammonium disappearance and nitrate formation rates of second application of ammonium sulfate in an acidic soil. The application of ammonium sulfate decreased pH of soils. The ammonium disappearance and nitrate formation rates were low in the soils samples having low pH. (author)