Cellulose-acetate filter disks were found convenient for the cultivation of lichen mycobionts and artificial re-synthesis of lichens, and using this method of culture we tested the effects of acidification on Cladonia cristatella Tuck. Mycobionts subjected to short-term strongly acidic conditions showed decreased formazan production compared to colonies grown at optimal pH 5.0. Disk-supported synthetic lichens grown at pH 3.0 or 5.0 exhibited no significant differences in pigment chemistry or photosynthetic efficiency compared to those at pH 7.0, but all of these parameters changed at pH 1.5. Chlorophyll a integrity significantly decreased under all treatments involving acidified water, with the highest amount of degradation at pH 1.5. At pH 1.5, significantly decreased concentrations of both β-carotene and total carotenoids were observed. A significant decrease in chlorophyll a fluorescence was also shown at pH 1.5.