EFFECTS OF ACID IRRIGATION AND LIMING ON THE PRODUCTION OF FRUIT BODIES BY ECTOMYCORRHIZAL FUNGI

The aim of this work was to examine the effects of an increase in acid rain upon community diversity and productivity of the ectomycorrhizal fungi in a Norway spruce stand and the possible amelioratory effects of liming. No obvious adverse effects on either the diversity or produ ctivity were found. Acid irrigation appeared to enhance the fruiting o f Russula ochroleuca, as did irrigation with 'normal' rain. A combinat ion of acid irrigation and liming resulted in a large increase in the fruiting of Hygrophorus pustulatus. Thirty times more fruit bodies wer e recorded from this treatment than from the control. A principal comp onent analysis of the fruit body data suggested that soil organic hori zon pH may be an important determinant of ectomycorrhizal community st ructure within the spruce stand.