Aquatic insects as indicators of water quality: the case of Khersan River, Iran

Aquatic insects may serve as reliable indicators of freshwater ecosystem quality and health. This study aimed to assess the diversity of aquatic insects in relation to water quality parameters along the Khersan River in southwestern Iran. Aquatic insects were sampled at five sites during four seasons in ۲۰۲۲. Physicochemical water parameters and riparian vegetation were examined at the study sites. A total of ۲,۰۵۷ insect specimens, representing ۳۶ genera and ۷ orders, were identified. The highest diversity was observed at Site ۴ (Shannon index: ۳.۰۴۵; Evenness: ۰.۸۷۹). The presence of sensitive taxa (e.g., Ephemeroptera and Trichoptera) recorded in most sites indicated good water quality, despite local disturbances affecting some areas. This study highlights the ecological significance of the Khersan River in its watershed basin ecosystem and underscores the importance of integrating biological and chemical monitoring approaches to promote public health.