Die Bodenkultur - Journal for Land Management, Food and Environment

P. Hartmann, H. Fleige, R. Horn:

Proof of fly ash deposition in forest soils and the effects on soil physical properties


In this paper, we present soils of forest regions in Saxony and Saxony-Anhalt (Germany), which had been influenced by industrial emissions for decades, in particular by lignite fly ashes. The enrichment of mineral fly ash particles could be proven directly by the soil horizon designation, by texture analyses and by scanning electron microscopy and indirectly by changed soil physical properties. In both study areas, the effects of fly ash enrichment were similar. Close to the emission sources (where there was an accumulation of sandy fly ash), particle density, air capacity, and saturated hydraulic conductivity were increased, whereas the water available to plants and water repellency was decreased. Coarse pores (air capacity) and saturated hydraulic conductivity were comparatively reduced with increasing distance from the emission source of the fly ash, corresponding with less accumulation of ash of decreasing size, whereas plant available water and soil water repellency increased. The investigated properties are partially highly correlated with each other and indicate that the enrichment of fly ash changed the total functionality of forest floor horizons. Key words: Forest floor horizon, fly ash, scanning electron microscopy, soil physical properties.