Diversity of Trichoptera Fauna and its Correlation with Water Quality Parameters at Pasak Cholasit reservoir, Central Thailand

Abstract

The objectives of this study were to study the diversity of the Trichoptera fauna and the physicochemical parameters of water quality, as well as the correlation between physicochemical parameters and biodiversity of Trichoptera fauna for monitoring of water quality. The specimens were sampled monthly using portable black light traps from January to December 2010 at the inflow and outflow of Pasak Cholasit reservoir. A total of 20,380 adult caddis flies representing 7 families and 27 species were collected from the sampling sites in the present study. The family Hydropsychidae contained the greatest number of species (29%, 8 species), followed by Leptoceridae (26%, 7 species), Ecnomidae (19%, 5 species), Psychomyiidae (11%, 3 species), Philopotamidae (7%, 2 species), and Dipseudopsidae and Xiphocentronidae (4%, 1 species). Results of CCA ordination showed that eleven selected physicochemical water quality parameters (i.e., air and water temperature, pH of water, dissolved oxygen, total dissolved solids, electrical conductivity, ammonia-nitrogen, nitrate-nitrogen, orthophosphate, sulfate and turbidity of water) were the important physicochemical factors to affect distribution of Trichoptera assemblages. Results revealed that the order Trichoptera, identified to species can be potentially used to assess environmental water quality status in freshwater ecosystems.