Research on the variability of physico-chemical parameters characterising acid precipitation at the Jeziory Ecological Station in the Wielkopolski National Park (Poland)

Here the water quality of precipitation at the Adam Mickiewicz University E cological Station is presented for the period 1992-1997 to examine one of t he main factors causing the degradation of the natural environment of the W ielkopolski National Park. In the course of daily observations the amount o f rainfall, its electrical conductivity and pH were measured. As much as 61 % of the tested precipitation had a pH < 4.6, and 92% had a pH < 5.6: some very low pH values, even below 3.0, were occasionally observed. The annual volume-weighted average pH during the full period was 4.28 and the lowest y early average was 3.92 (1994). The chemical composition of precipitation sh owed the dominance of sulphate and calcium ions. Fluoride ions also contrib uted significantly to the anion charge. There were also small amounts of he avy metals and polycyclic aromatic hydrocarbons. A chemical analysis of thr oughfall showed a considerably increased concentration of some ions, in par ticular potassium. (C) 1999 Elsevier Science B.V. All rights reserved.