Effects of ash fertilization and prescribed burning on macronutrient, heavy metal, sulphur and Cs-137 concentrations in lingonberries (Vaccinium vitis-idaea)

The effects of ash fertilization and prescribed burning on the P, K, Ca, Mg , Mn, S, Fe, Al, Cu, Zn, Cd, Cr, Ni and Cs-137 concentrations in lingonberr y (Vaccinium vitis-idaea L.) berries were investigated in a 100-year-old Sc ots pine (Pinus sylvestris L.) stand growing on a dry site in central Finla nd. The treatments were control, prescribed burning and three ash-fertilize r doses of 1000, 2500 and 5000 kg ha(-1). The size of the plots was 30 x 30 m, and there were four replications per treatment. Lingonberries were coll ected two (1991) and seven (1996) growing seasons after the treatments. Ash fertilization had no effect on the heavy metal concentrations in the berri es. Potassium was the only macronutrient whose concentration in the berries significantly increased after ash fertilization (5000 kg ha(-1)). Prescrib ed burning increased the berry Cd concentrations, which, however, remained low even after prescribed burning, The berry Cs-137 concentrations decrease d as a result of ash fertilization and prescribed burning. The reduction in Cs-137 concentrations caused by ash fertilization may be an important find ing especially for areas where the picking and consumption of berries has t o be restricted as a result of radioactive fallout. (C) 2000 Elsevier Scien ce B.V. All rights reserved.