Fungal Descomposer Diversity in Andean Streams Across a Land-Use Gradient

Abstract

Abstract: In the Tropical Andes, land-use change has caused severe alterations in hydrological patterns, water quality, ecosystem functions and biodiversity in the streams. In these ecosystems, aquatic fungi play a relevant role, particularly in the nutrient cycle. However, their diversity has been poorly studied. Given the increasing pressure on Andean streams, it is critical to know fungal diversity and better understand the impacts of land-use change on aquatic fungi. We analyzed the effects of land use and leaf-litter type on the richness and composition of aquatic fungi in 12 Andean streams in southern Ecuador, in addition to the influence of the environmental stressors related to land use. Fungal richness decreased along the land-use gradient, while no significant differences were found between leaf-litter types. However, the fungal taxonomic composition was significantly different between land uses and between leaf litter types. The determining environmental stressors for aquatic fungi were pH and conductivity. Andean streams are a container of high fungal richness, and their communities are influenced by land use, its associated degradation of the environmental features and litter type.