THE CONTRIBUTION OF OZONE TO FOREST DECLINE

More than 10 years of intensive research into forest decline in German y has ascertained that the full extent of the visible damage cannot be explained by just one of the current hypotheses on forest decline. On e of the prominent hypotheses is that chronic exposure of forest trees to ozone is probably one of the primary causes of forest decline. The aim of this paper is the critical review of a number of recent result s dealing with the ozone hypothesis from a plant physiological point o f view. The synopsis focusses on the effects of ozone on conifers beca use the most extensive data are available for coniferous trees, especi ally for spruce (Picea sp.) and pine (Pinus sp.) trees.