Biomass burning in eastern Europe during spring 2006 caused high deposition of ammonium in northern Fennoscandia

High air concentrations of ammonium were detected at low and high altitude sites in Sweden, Finland
and Norway during the spring 2006, coinciding with polluted air from biomass burning in eastern
Europe passing over central and northern Fennoscandia. Unusually high values for throughfall deposition
of ammonium were detected at one low altitude site and several high altitude sites in north
Sweden. The occurrence of the high ammonium in throughfall differed between the summer months
2006, most likely related to the timing of precipitation events. The ammonia dry deposition may have
contributed to unusual visible injuries on the tree vegetation in northern Fennoscandia that occurred
during 2006, in combination with high ozone concentrations. It is concluded that long-range transport
of ammonium from large-scale biomass burning may contribute substantially to the nitrogen load at
northern latitudes. Ammonium deposition,Biomass burning,Vegetation damage,Northern latitudes, Eastern Europe