THE SEASONAL-CHANGES OF KERATINOLYTIC FUNGI IN SEDIMENTS OF CATALONIAN RIVERS (SPAIN)

The Catalonian river sediments were found to be rich in keratinolytic fungi. The keratinolytic fungal populations showed clear seasonal chan ges in the river sediments. The main factors 'regulating' these popula tions in such habitat were temperature, dissolved oxygen concentration , pH, ammonium, nitrates, total fungal number, BOD5, water poisons (cy anides, detergents, phenols), salinity and, presumably, strong insolat ion associated with low water levels. The last was probably of special importance in the deterioration of the fungal populations in the spri ng/summer season. A toxic effect on keratinolytic fungi in sediments w as observed. Chrysosporium keratinophilum was found to be most resista nt to industrial contaminants and salinity. Therefore, this species co uld be used as an indicator of water pollution.