Petrozhitskaya L.V. 2018. [Influence of mining works on the structure of blackfly communities in the mountain river of north-eastern Tuva] // Euroasian Entomological Journal. Vol.17. No.5: 328–336 [in Russian, with English summary].
Institute of Systematics and Ecology of Animals, Russian Academy of Sciences, Frunze Str. 11, Novosibirsk 630091 Russia.
Absract. Influence of mining on the communities of blackflies (Diptera, Simuliidae) as a component of macrozoobenthos was analysed in the basin of mountain river Ak-Khem in the north-eastern Tuva. A total of 8 species of blackflies were identified: Gymnopais andrei Vorobets, 1984, G. trifistulatus Rubtsov, 1955, Helodon alpestris (Dorogostaisky, Rubtsov & Vlasenko, 1935), Prosimulium intercalare Rubtsov, 1956, P. kolymense Patrusheva, 1975, P. tridentatum Rubtsov, 1940, Metacnephia amsheevi Usova & Bazarova, 1990, M. kirjanovae (Rubtsov, 1956), which accounted for about 30% of species richness in the Bolshoy Yenisei River basin. The species Gymnopais andrei was registered in Tuva and the Altai-Sayan mountain system for the first time. The blackflies and mayflies accounted for 28 and 33% of the collected material. The species richness of Ephemeroptera, Plecoptera, Trichoptera in the Ak-Khem river basin included 44 taxons. Mining leads to a decrease in water quality by chemical characteristics, especially heavy metals and sediments. The insects of amphibiotic complex completely disappeared in the zone of immediate proximity to the contamination site, the biotic index EPT fell up from 11 to 0 in the mainstream of the river. As water arrives from the tributaries, the habitat is improved and communities are gradually restored in the lower sections of the river (EPT = 15). The use of blackflies as bioindicators is suggested, the biotic indices EPS (the total number of species of Ephemeroptera, Plecoptera, Simuliidae, is within 7–14 ), along with the EPT, will improve the effectiveness of assessing the state of the aquatic environment and in particular the increasing volumes of bottom sediments. The long-term mining of polymetallic ores in the east of Tuva carries the risk of contamination by solid sediments with heavy metals not only the Ak-Khem River, but also the Bolshoy Yenisei — the largest clean river of Tuva. Monitoring of the Ak-Khem River with help of bioindicators, including not only stoneflies, mayflies, caddis flies, but also blackflies will increase the effectiveness of assessing the increasing solid flow of the river.
KEY WORDS: blackflies, Simuliidae, macrozoobenthos, species richness, community structure, watercourses, mining, bioindicator, heavy metals, bottom sediments.