Fertilizing and liming in a heather area of Norway

In a 6 years' field experiment in a podzolized heather area in Norway the effects of liming and P and Cu fertilization were tested versus changes in vegetation and soil chemistry. The vegetation altered slowly, particularly the woody species, but pronounced over years. Liming had a positive effect on all species except Deschampsia flexuosa and Vaccinium myrtillus, P tended to favour all except V. myrtillus, and Cu promoted all except Nardus stricta, V. oliginosum and V. myrtillus. Surface spreading of liming material and fertilizers caused distinct lime, phosphorus and copper effects and interactions in the soil litter layer. Liming markedly increased pH and Ca level and stimulated microbial activity, whilst the fertilizers increased P and Cu availability in soil. Cu fertilization counteracted a feared Cu deficiency when liming marginal soils. Gradually the changes penetrated into deeper soil layers. This strong chemical influence led the podzol into a cambisol cycle, characterized by retention of humus in the E layer, accompanied by a slight increase in pH, elevated levels of Kjeldahl-N, AL dissolved and exchangeable Ca, and in CEC and BS.