Ammonium (NH4) (Positive Ions) in Precipitation: A Presentation of Data from the European Air Chemistry Network

摘要

The ammonium content of monthly precipitation samples collected in the European Air Chemistry Network (EACN) was evaluated for the period 1955 to 1979. A median two way table statistical analysis found a seasonal variation of the ammonium concentration with high concentration in November through February and low concentration in June through August. A slight increase in concentration, corresponding to an annual increase of about 1% per year. Transformations may have occurred more often during the early part of the operation of the network when higher pH values were more common than they are now. It is observed that biological growth is more frequent in samples with a high pH.