Žaltauskaitė, J. and Juknys, R. 2007. Atmospheric Deposition and Canopy Interactions in Urban Scots Pine Forest.  Baltic Forestry 13 (1): 68-73

The investigations of atmospheric deposition were carried out in 2002 in urban Scots pine (Pinus sylvestris L.) stand in second biggest Lithuanian city - Kaunas. The main aim of this study was to investigate atmospheric deposition and Scots pine canopy interactions at urban site and get more insight in dependency of precipitation chemistry on canopy closure. It was established that throughfall enrichment by anions was caused mainly by wash-off of dry deposited material, although there was a slight canopy exchange of chloride. By contrast, cations, and especially potassium enrichment came mainly from canopy leaching (p<0.05). Concentration of investigated ions in throughfall demonstrated a linear relationship with canopy closure. Twofold increase in canopy closure (40-80 %) led to an increase in the Cl¨ ions concentration in throughfall by factor 3 and the concentrations of SO4²¨, NO3¨ increased more than twice. The potassium concentration in throughfall grew by factor 2.4 along with twofold increase in canopy closure.

Key words: bulk deposition, canopy closure, canopy interaction, Scots pine, net throughfall, throughfall