Fungal species richness in Western Ghat streams (southern India): Is it related to pH, temperature or altitude?

Foam and leaf samples from ten streams in the Western Ghat region (south-west India) were examined for aquatic hyphomycetes. A total of 47 conidial forms were distinguished, 15 of them unknown. Cluster and principal component analysis suggested that stream category (defined primarily by distance from source) was the primary factor connected with the composition of fungal communities. Data from the current and earlier studies in the same region showed a negative correlation between species number and pH of streams (r = 0.3, p = 0.18). The correlation was stronger (r = 0.4, p = 0.051), when one stream with an unusually high number of species was excluded. A resampling test suggested that fungal species richness differed among stream categories, with the highest numbers occurring in mid-altitude streams.