Cadmium and zinc migration in Scots pine stands growing in contaminated areas from metallurgical plant emissions

The accumulation of cadmium and zinc in aboveground and belowground organs of Scots pine ( Pinus sylvestris L.) and the metal migration extents in the soil–plant system were analysed for the stands growing in contaminated areas from metallurgical plant emissions. The pine stands of the comparable age (38–45 years old), and a similar structure, selected for research, is grown in the sanitary protection zone of the city of Lipetsk (Lipetsk Region, Russia) in the vicinity of the metallurgical combine (Novolipetsk Steel). Using atomic absorption spectrometry determined cadmium and zinc content in the soil, fine (< 1 mm) roots, annual shoots, and needles. In the impact zone, the Novolipetsk Steel releases significant contamination of the soil’s surface layers with cadmium and zinc. The present investigation identifies the changes in cadmium and zinc content in the soil that correlated (moderately and strongly) with acidity and humus in the ground. The pine fine roots in the impact zone take in these metals sufficiently, with zinc being absorbed more intensively than cadmium. As against the fine roots, it has been indicated that one-year needles and shoots actively cumulate zinc. The biological accumulation and migration coefficient values show that zinc is actively stored in Scots pine annual needles and shoots.