Effects of Ash Fertilization on Forest Berries

1991

23 S.

4 Abb., 8 Tab., 44 Lit. Ang.

Bandaufführung

37277

The effects of peat ash and wood ash on the elemental composition and weight of the berries of Vaccinium myrtillus, V. vitis-idaea, V. uliginosum and Rubus chamaemorus were examined. Soil samples taken from the same sites were also analysed. The material was collected from stands growing on mineral soils and peatlands is the vicinity of Oulu in late summer 1988. During the summer (1988) following fertilization wood ash (10 t/ha) the Mn, Ca and Mg concentrations in the berries of V. myrtillus and V. vitis-idaea decreased. The effect of peat ash (20 t/ha) was most clearly apparent as an increase in the Fe concentrations in the berries. During the same year when fertilized, wood ash increased the weight and yield of V. myrtillus berries on the mineral soil site. Peat ash appeared to somewhat reduce the yield of V. myrtillus berries both in 1988 and 2-8 years earlier fertilized mineral soil sites. The Cd concentration in the peat ash was 9 g/t, and 31 g/t in the wood ash. However, levels exceeding the maximum limits for human consumption were not found in berries. Natural variation between the berry species was considerable. The highest Cd concentrations occurred in the R. chamaemorus berries and the lowest in the V. myrtillus berries. Repeated fertilization in the same area should be avoided in order to prevent the excess accumulation of Cd in the soil.