The influence of industry on the tree-ring width of pines [Pinus sylvestris L.] living in the Olkusz region

Tree−ring analysis of pine stands living under the influence of industry in south−eastern part of Silesia−Krakow Upland was performed for the last years. Now the new transect was added in the Olkusz region. Previous studies showed the distinct relationship between number of trees with observed reductions and distance from main source of pollution it this region. On the sites localised nearest to zinc−works "Bolesław" the value and the duration of reduction periods were the biggest. On the sites of new transect (OL VI) situated to the north from site OL 15, the influence of zinc−works is rather uncertain. Because of the time of occurrence and the distance form zinc−work, the reductions observed here seem to be the reaction to the other factor – perhaps the local source of pollution. To explain this matter further studies in this region should be done