Augustaitis, A. 2011. Impact of Meteorological Parameters on Responses of Pine Crown Condition to Acid Deposition at Aukštaitija National Park. Baltic Forestry 2011(2): 205-214

Climate changes may affect sustainable forest development, its adaptation to unfavourable environmental conditions and first of all to air concentration of acidifying species. However, it is still unclear whether local meteorological conditions reduce or enhance air pollution effects on forest health. To reduce these uncertainties data set of crown defoliation of 20 Scot pine stands located in north-eastern part of Lithuania and obtained since 1994 was used. The findings revealed that meteorological parameters being less significant in relationships with pine crown condition than acidifying species resulted in their deposition variation. Increase in precipitation amount over the dormant period and decrease over vegetation enhance negative effect of the acidifying species on pine crown condition. However, if climate changes follow the long term tendencies, reduction of the negative effect of air concentrations of acidifying species and their deposition can be expected, despite the rise in negative effect of new threat for forest ecosystem – the increase in deposition of the ammonia compounds.

 Key words: climate change, acidifying species, interaction, pine defoliation.