Air Pollution and Forest Health Studies along a South-North Transect in Poland1

2 Professor of Natural Sciences, Physicist, Biologist, and Biologist, respectively, Institute for Ecology of Industrial Areas, Kossutha 6, 40-833 Katowice, Poland. Abstract Air pollution, bulk deposition and throughfall, soil characteristics, needle chemistry, and forest injury were studied on six permanent plots from the south (Brenna and Salmopol in the Beskidy Mountains) to the north (Gac, the Baltic Sea coastal area) in Poland. The concentrations of sulfur dioxide and nitrogen dioxide were the highest at the Katowice location and the lowest at Gac. Annual mean concentrations of sulfur dioxide at the Brenna, Salmopol, Katowice, and Puszczykowo sites, have exceeded the critical level of 20 μg m-3 proposed by United NationsEconomical Committee for Europe (UN-ECE) bodies, and the Polish national standard (32 μg m-3 for the whole country, and 11 μg m-3 for special protected areas, e.g. National Parks). Nitrogen dioxide concentration has neither exceeded the UN-ECE nor the Polish national standards for the whole country (30 and 50 μg m-3, respectively). Bulk deposition from all locations was acidic. The pH of throughfall in spruce stands was lower than the bulk deposition by about 0.5 of a unit. A larger decrease of pH has been found occasionally. Concentration of all elements measured was higher in throughfall as compared to bulk deposition. However, the differences in concentration of elements between bulk deposition and throughfall varied. The differences were from three to five times for sulfates, but for nitrogen compounds, such as nitrates and ammonium, differences were smaller or did not exist at all. The soil pH of all plots ranged from 2.9 to 3.6 (H2O) in the organic layer. The highest concentrations of lead and zinc were found in the organic layer of the sites in southern Poland. The greatest needle loss (crown transparency) was found at the highest elevation site (Salmopol) for Norway spruce (Picea abies) and in the most polluted site (Katowice) for Scots pine (Pinus sylvestris). The smallest crown transparency of spruce was found for the Gac location. Discoloration of needles was the highest at Gac, followed by Katowice and Salmopol. Insects contributed to the observed higher crown transparency on plots at Brenna and needle discoloration at Gac.