THE EFFECT OF COAL-MINE EFFLUENT ON FUNGAL ASSEMBLAGES AND LEAF BREAKDOWN

Although fungi play an important role in the functioning of many freshwater systems, information on their response to pollutants is scarce. The aim of this study was to investigate the effect of coal-mine effluent on the structure and functioning of fungal assemblages. Fungi present above and below the effluent outfall of a disused coal mine surveyed. In the upstream site there were more species (23 compared with 20) and, possibly more importantly, twice as many aquatic Deuteromycotina. It is this group of fungi, which includes the aquatic Hyphomycetes, that has been implicated in leaf litter breakdown, and litter-bag experiments confirmed that decomposition rates were reduced below the effluent outfall. In addition, leaves incubated at the downstream site had higher C:N ratios. Results from this study suggest that the mine effluent was having an effect on: the fungi present, the rate of leaf breakdown and the biochemical composition of decomposing leaves. The implications of these effects for invertebrate shredders are considered.