Biodiversity, spatial distribution and seasonality of heterotrophic straminipiles and true zoosporic fungi in two water bodies exposed to different effluents at Assiut (Upper Egypt).

Abstract

Patterns of frequency, biodiversity and seasonality of fungi-like organisms and true zoosporic fungi in relationship with some abiotic factors of two water bodies exposed to various effluents at Assiut Governorate (Upper Egypt) were investigated. Thirty-four species related to ten genera were isolated from the El-Zinnar irrigation canal and the El-Ibrahimia canal, which receive treated sewage water and the industrial effluents of a factory for oils and detergents, respectively, using the baiting technique during four seasons (from winter 2017 to autumn 2018). The highest fungal diversity was recorded during winter, followed by autumn and spring, whereas summer was the lowest in species diversity. Achlya, Dictyuchus, Allomyces and Pythium were the prevalent genera, whereas Brevilegnia and Pythiopsis were the least frequent ones. Some fungal taxa were present throughout the year while others were highly restricted, occurring in only one season. The species composition and community structure of the heterotrophic straminipiles and true zoosporic fungi varied in spatial distribution and exhibited seasonal variations, probably influenced by particular abiotic water characteristics, sampling site and season. Sites which directly receive either treated sewage water or industrial effluents were the poorest in straminipiles and true zoosporic fungi, and can be regarded as stressful environments where some abiotic parameters were excessive. Seasonality and biodiversity of the surveyed organisms are mainly dependent on water temperature, conductivity, most of the determined cations and anions, but pH did not exhibit any considerable impact. It is assumed that the existence of some fungal taxa at polluted sites may have a potential source of fungi beneficial for bioremediation and xenobiotic transformation.