Precipitation chemistry in a forested study area of the Chojnów Forest District in the years 2004-2007

Abstract

Analyses of precipitation in the forest environment were conducted in the years 2004– 2007 in a premanent observation plot established in a pine forest stand growing in a mixed fresh coniferous forest habitat in the Chojnow Forest District. The amount and chemistry of atmospheric precipitation in the open field and under canopies were analysed. Electrical conductivity, pH, and concentrations of Ca, Mg, Cl, NO3, SO4, Na, K, Fe, Mn, Al, NH4, PO4, Zn, Cd, Cu and Pb were determined in collected samples. Mean annual precipitation in the open field for the years 2004–2007 was 443 mm. Mean pH (volume weighted) in this period equalled 4.8 and electrical conductivity – 47 μS·cm –1 . Mean precipitation under trees crowns (411 mm·y –1 ) was lower than bulk precipitation. Throughfall was characterised by lower pH (mean 4.2) and higher conductivity (62 μS·cm –1 ). Throughfall was enriched, mostly in hydrogen ions, Mn, K, Al, Mg, and Ca ions with respective enrichment factors of: 67, 20, 9, 5, 4 and 2.