Deposition is measured in twelve plots of intensive monitoring of the ICP Forests Programme. Deposition of acidifying and eutrophying substances, basic cations, fluorine, and chlorine in forest and forest soil is monitored in open plot in the near vicinity of the monitoring plot (bulk), and in the stand (throughfall). In the beech stands also stemflow is measured, which contributes significantly to deposition of substances in the stand.
To quantify atmospheric deposition, the concentration of individual substances in the rain and snow precipitations is stated. Total deposition is calculated as a product of substance concentration in precipitation water and total precipitation amount in given month.
In summer period, three polyethylene gutters 0.2 m wide and 2 m long, are used as measuring equipment for throughfall deposition. In winter they are replaced by four cylindrical snowmeters of the diameter of 23.3 cm. In the beech stands also equipment for measuring of the stemflow is installed in selected trees.
In open plot, in summer months, two cylindrical catching vessels, 23.3 cm in diameter, are installed, and in winter two snow-meters of the same diameter.
In summer, precipitation water is conducted from the catching vessels to storing containers, placed under the soil surface, to keep stabile temperature and to prevent allae growth in the sunshine.
Samples of precipitation water are taken in ten day intervals. Samples are frozen and transported regularly to the FGMRI laboratory. Before analyzing, mixed monthly samples are prepared, according to the amount measured, and treated according to the method as given in the ICP Forests manual. Following parameters are stated: pH, alkalinity, conductivity in 25°C, S-SO42-, N-NO3-, N-NH4+, Ca-, F-, Al, Ca, Cu, Fe, K, Mg, Mn, Na, P-PO43- , Zn, TN and DOC.
