Fungi and cellulolytic activity associated with decomposition of Bauhinia purpurea leaf litter in a polluted and unpolluted Hong Kong waterway

A survey of fungal succession on decomposing Bauhinia purpurea leaves in the unpolluted Tai Po Kau Forest Stream (TPKFS) and the animal waste polluted Lam Tsuen River (LTR) was carried out. Most of the 28 aquatic hyphomycete species found were cosmopolitan or frequently reported in temperate regions. Clavariopsis aquatica, Lunulospora cymbiformis and Flagellospora penicillioides were the dominant species at both sites. Among the 49 geofungi species recorded, lymaphilic species were commonly observed in the polluted LTR eg Geotrichum candidum, Fusarium oxysporum, Mucor racemosus and lymaxenes in the TPKFS (eg Humicola spp., Trichoderma spp. and Gliocladium roseum). Species richness of aquatic hyphomycetes was higher in the TPKFS (27 species) than in the polluted LTR (14 species), whereas for the associated geofungi, it was higher in the LTR (35 species) than in the TPKFS (28 species). Conidial production was also higher in the TPKFS. Aquatic hyphomycetes and geofungi showed a complementary sequence of dominance in winter and summer, respectively, in the clean TPKFS. Higher cellulolytic activity occurred in winter than summer leaf litter. (See also 93L/01297) -from Authors