COMPARISON OF SEVERAL BIOINDICATOR METHODS IN MONITORING THE EFFECTS ON FOREST OF A FERTILIZER PLANT AND A STRIP MINE

The fertilizer plant and strip mine are located at Siilinjarvi in central Finland. In the years 1985-1987, a study was made in their surroundings of the visible and ultrastructural injuries in needles of Norway spruce (Picea abies (L.) Karst.), of the visible and cellular injuries in epiphytic lichens growing on spruce branches, and of the element contents of the spruce needles and the lichen Hypogymnia physodes. Zones of severe and slight injury could be distinguished with regard to both the needles and lichens and these zones had expanded considerably since surveys made about 10 years earlier. In this study the zone of slight injury in the needles reached about 6 km from the factory and that of the lichens about 7 km. The highest sulphur concentrations were measured in the spruce needles (1 100-1 300-mu-g) and lichens (1 900-2 800-mu-g) in the vicinity of the factory, and these concentrations declined exponentially, reaching the background level 7-8 km and 8-9 km from the factory, respectively. The fluoride distribution had two peak areas, which were especially marked in the needle material, showing that both the factory and apatite strip mine are important sources of fluorides. The apatite dust also clearly elevated the Ca, P, K and Mg contents of lichens in the vicinity of the strip mine, but the increase was not so clear in the needles. In the ultrastructural analyses of spruce needles and lichens, types of injury could be found that were related to the effects of acidic pollutants and fluorides. The visual observations of the needles and lichens and the chemical analyses of the material provided consistent indications of the extent of the area affected by the industrial complex.