IONIC STABILITY OF PRECIPITATION SAMPLES

Event and weekly precipitation sampled with three types of collectors was stored under five different conditions and analyzed throughout a six-week time period to monitor changes in ionic composition. Ca++, Mg++, Na+, K+, H+, NH4+, SO42-, NO3- and Cl- were the constituents under observation. Dramatic variations in the concentrations of some species are attributable to the sample particulate loading. Although cooling retarded changes in ionic composition, immediate filtering after wet-only collection was the most effective means of retaining sample integrity and preventing adsorption-desorption reactions. © 1978.