A. N. Matveev¹, V. P. Samusenok¹, A. L. Yuriev¹, A. I. Vokin¹, E. A. Erbaeva¹, G. P. Safronov¹, N. A. Rozhkova², V. P. Semernoy³, T. Ya. Sitnikova², K. V. Tarakanova¹ 

¹ Irkutsk State University, Irkutsk, Russian Federation 

² Limnological Institute SB RAS, Irkutsk, Russian Federation 

³ P. G. Demidov Yaroslavl State University, Yaroslavl, Russian Federation

The aim of the work is to study the biodiversity and production characteristics of macrozoobenthos in the mountain lake Balan-Tamur in the upper reaches of the Barguzin River, a large tributary of Lake Baikal (Eastern Siberia). Lake Balan-Tamur is one of a series of glacial and thermokarst lakes in the intermountain Amut Depression. Essentially a lake-like extension of the Barguzin River, it covers an area of approximately 1 km² and has a maximum depth of 16.5 m. Quantitative sampling of macrozoobenthos was carried out using a Petersen sampler (small model) in the third ten-day period of June 2006 from 11 stations; in the first ten-day period of April 2008 from 5 stations from under the ice; in the second ten-day period of August 2008 from 12 stations. A total of 67 samples were collected in all depth zones. The lake has a very high taxonomic diversity of benthic invertebrates – 126 species and forms from 16 taxonomic groups. Chironomids dominate in species diversity in all study seasons at all depth ranges. This group in the lake is represented by 70 species and larval forms from 5 subfamilies, with the Chironominae and Orthocladiinae subfamilies dominating in the number of species (30 species in each). Subdominants include caddisflies (16 species), oligochaetes (7 species), gastropods (6 species) and bivalves (4 species). Caddis flies were observed only in the littoral and sublittoral zones down to depths of 5 m. Gastropods and megaloptera were also observed in this depth range. In the structure of macrozoobenthos, chironomids dominate at all deep horizons; at the horizon of 1–3 m, the proportion of oligochaetes and nematodes (by number) also stands out, and at the depth of 5–7 m, oligochaetes and caddisflies. Rheophilic amphibiotic insects (mayflies, stoneflies, and caddisflies) are significantly represented, although they are not part of the dominant complex. Average abundance and biomass of macrozoobenthos remain relatively high regardless of season: 5,500–11,100 ind/m² and 16–17 g/m². The highest production rates of macrozoobenthos are associated with maximum depths (10–14 m), which is due to the instability of the water level regime and its significant fluctuations, reaching an amplitude of 2–2.5 m. In this depth range, the average abundance in all studied seasons does not fall below 4967.3 ind/m², and the biomass is 16.819 g/m². Lake Balan-Tamur is characterized by the highest quantitative indicators of macrozoobenthos among similar studied flowing lakes in the Baikal basin

Matveev Arkadiy Nikolaevich, Doctor of Sciences (Biology), Professor, Head of Chair Irkutsk State University 1, K. Marx st., Irkutsk, 664003, Russian Federation e-mail: matvbaikal@mail.ru

Samusenok Vitaliy Petrovich, Candidate of Sciences (Biology), Associate Professor Irkutsk State University 1, K. Marx st., Irkutsk, 664003, Russian Federation e-mail: samusenk@mail.ru 

Yuriev Anatoliy Leonidovich, Candidate of Sciences (Biology), Associate Professor Irkutsk State University 1, K. Marx st., Irkutsk, 664003, Russian Federation e-mail: yuriev@bk.ru

Vokin Aleksey Innokentyevich, Candidate of Sciences (Biology), Associate Professor Irkutsk State University 1, K. Marx st., Irkutsk, 664003, Russian Federation e-mail: vokin@bk.ru

Erbaeva Engelsina Aleksandrovna, Candidate of Sciences (Biology) Irkutsk State University 1, K. Marx st., Irkutsk, 664003, Russian Federation

Safronov Gennadiy Petrovich, Candidate of Sciences (Biology) Irkutsk State University 1, K. Marx st., Irkutsk, 664003, Russian Federation e-mail: gsafro@bio.isu.runnet.ru

Rozhkova Natalya Anatolyevna, Candidate of Sciences (Biology), Senior Research Scientist Limnological Institute SB RAS 3, Ulan-Batorskaya st., Irkutsk, 664033, Russian Federation e-mail: rozhkova@lin.irk.ru

Semernoy Viktor Petrovich, Doctor of Sciences (Biology), Professor P. G. Demidov Yaroslavl State University 14, Sovetskaya st., Yaroslavl, 150000, Russian Federation e-mail: semernoy@bio.uniyar.ac.ru

Sitnikova Tatiana Yakovlevna, Doctor of Sciences (Biology), Leading Research Scientist Limnological Institute SB RAS 3, Ulan-Batorskaya st., Irkutsk, 664033, Russian Federation e-mail: nina@lin.irk.ru

Tarakanova Ksenia Valeryevna, Engineer Irkutsk State University 1, K. Marx st., Irkutsk, 664003, Russian Federation e-mail: tarakanova_kv@mail.ru

1. Matveev A.N., Samusenok V.P., Yuriev A.L., Vokin A.I., Bondarenko N.A., Rozhkova N.A., Sitnikova T.Ya., Erbaeva E.A., Misharina E.A., Arov I.V., Tarakanova K.V., Alekseev S.S. Bioraznoobrazie i struktura bioty ozera Frolikha (Severnyi Baikal, Vostochnaya Sibir) [Biodiversity and Biotic Structure of Lake Frolikha (Northern Baikal Region, East Siberia). Bul. Irkutsk St. Univ. Ser. Biol. Ekol., 2019, vol. 30, pp. 58-92. (in Russian) https://doi.org/10.26516/2073-3372.2019.30.58 
2. Matveev A.N., Samusenok V.P., Rozhkova N.A., Bondarenko N.A., Kravtsova L.S., Sheveleva N.G., Slugina Z.V., Yur'ev A.L. Biota Vitimskogo zapovednika: struktura bioty vodnykh ekosistem [Biota of Vitim Reserve: structure of biota of hydrosystems]. Novosibirsk, Geo Publ., 2006, 255 p. (in Russian) 
3. Vdovina O.N., Bezmaternykh D.M. Factors of macrozoobenthos formation in low-mountain lakes of the Russian Altai. Proc. Zool. Inst. RAS, 2024, vol. 328, no. 2, pp. 268-284. (in Russian). https://doi.org/10.31610/trudyzin/2024.328.2.268 
4. Voronov A.G. Biogeografiya [Biogeography]. Moscow, Moscow St. Univ. Publ., 1963, 339 p. (in Russian) Vyrkin V. B. Morfometriya i nekotorye osobennosti prirody ozer Amutskoi kotloviny [Morphometry and some natural features of the lakes of the Amut Basin]. Ozera Barguzinskoi doliny [Lakes of Barguzin depression]. Bogdanov V.T. (ed.). Novosibirsk, Nauka Publ., 1986, pp. 43-46. (in Russian) 
5. Vyrkin V. B. Sovremennoe ekzogennoe relefoobrazovanie kotlovin baikal'skogo tipa. Irkutsk : Izd-vo IG SO RAN, 1998. 175 p. (in Russian) 
6. Matveev A.N., Samusenok V.P., Yuriev A.L., Andreev R.S., Pomazkova G.I., Bondarenko N.A., Rozhkova N.A., Slugina Z.V. Gidrobiologicheskaya i ikhtiologicheskaya kharakteristika Verkhnekicherskikh ozer (bassein oz. Baikal) [Hydrobiological and ichthyological characteristics of lake group in upper reaches of Kichera River (Baikal basin)]. Bull. Irkutsk St. Univ. Ser. Biol. Ekol., 2010, vol. 3, no. 2, pp. 36-53. (in Russian) 
7. Evstigneeva T.D., Lazareva V.I. Zoobentos ozer Barguzinskoi kotloviny [Zoobenthos of lakes of Barguzin depressiob]. Ozera Barguzinskoi doliny [Lakes of Barguzin depression]. Bogdanov V.T. (ed.). Novosibirsk, Nauka Publ., 1986, pp. 114-120. (in Russian) 
8. Zhadin V.I. Mollyuski presnykh i solonovatykh vod SSSR [Molluscs of fresh and brackish waters of USSR]. Series: Keys to fauna of USSR, vol. 46. Moscow-St.-Petersb., AS USSR Publ., 1952. 376 p. (in Russian) 
9. Zhadin V.I. Metody gidrobiologicheskogo issledovaniya [Methods of hydrobiological investigations]. Moscow, Vysshaya Shkola Publ., 1960, 189 p. (in Russian) 
10. Zhil'tsova L.A. Vesnyanki (Plecoptera). Gruppa Euholognata [Stoneflies (Plecoptera). Group Euholognata]. Fauna Rossii i sopredel'nykh stran [Fauna of Russia and adjacent countries]. St.- Petersb., Nauka Publ., 2003, no. 15, 538 p. (in Russian) 
11. Kozhov M.M. Presnye vody Vostochnoi Sibiri [Fresh waters of East Siberia]. Irkutsk, Irkutsk St. Publ., 1950. 367 p. (in Russian) 
12. Levanidov V.Ya. Biomassa i struktura donnykh biotsenozov reki Kedrovaya [Biomass and structure of bottom biocenoses of Kedrovaya River]. Presnovodnaya fauna zapovednika «Kedrovaya pad'» [Freshwater fauna of Kedrovaya pad' Reserve]. Vladivostok, Far East SC AS USSR Publ., 1977, vol. 45 (148), pp. 126-159. (in Russian) 
13. Lepneva S.G. Rucheiniki. Lichinki i kukolki podotryada tsel'noshchupikovykh (Integripalpia) [Trichoptera. Larvae and pupae of suborder Integripalpia]. Fauna SSSR [Fauna of USSR]. Moscow - St.-Petersb., AS USSR Publ., 1964, vol. 2, is. 1, 560 p. (in Russian) 
14. Lepneva S.G. Rucheiniki. Lichinki i kukolki podotryada kol'chatoshchupikovykh (Annulipalpia) [Trichoptera. Larvae and pupae of suborder Annulipalpia]. Fauna SSSR [Fauna of USSR]. Moscow, St.-Petersb., AS USSR Publ., 1966, vol. 2, is. 2, 560 p. (in Russian) 
15. Makarchenko E.A. Khironomidy Dal'nego Vostoka SSSR podsemeistv Podominae, Diamesinae i Prodiamesinae (Diptera, Chironomidae) [Chironomids of Russian Far East. Subfamilies Podominae, Diamesinae and Prodiamesinae (Diptera, Chironomidae)]. Vladivostok, Far East SC AS USSR Publ., 1985, 195 p. (in Russian) 
16. Ozera Barguzinskoi doliny [Lakes of Barguzin depression]. Bogdanov V.T. (ed.). Novosibirsk, Nauka Publ., 1986, 165 p. (in Russian) 
17. Opredelitel' nasekomykh Dal'nego Vostoka Rossii T. V. Rucheiniki i cheshuekrylye. Ch. 1. [Key to insects oo Russian Far East. Vol. V. Trichopterans and lepidopterans. Part 1]. Vladivostok, Dalnauka Publ., 1997, 540 p. (in Russian) 
18. Opredelitel' presnovodnykh bespozvonochnykh Rossii i sopredel'nykh territorii. T. 3. Paukoobraznye. Nizshie nasekomye [Key to freshwater invertebrates of Russia and adjacent territories. Vol. 3. Arachnids. Paleoptera]. S. Ya. Tsalolikhin (ed.). St.-Petersb., Nauka Publ., 1997. 439 p. (in Russian) 
19. Opredelitel presnovodnykh bespozvonochnykh Rossii i sopredel'nykh territorii. T. 4. Vysshie nasekomye. Dvukrylye [Key to freshwater invertebrates of Russia and adjacent territories. Vol. 4. Higher insects. Dipterans]. S.Ya. Tsalolikhin (ed.). St.-Petersb., Nauka Publ., 1999, 998 p. (in Russian) 
20. Opredelitel' presnovodnykh bespozvonochnykh Rossii i sopredel'nykh territorii. T. 5. Vysshie nasekomye [Key to freshwater invertebrates of Russia and adjacent territories. Vol. 5. Higher insects (Neoptera)]. S. Ya. Tsalolikhin (ed.). St.-Petersb., Nauka Publ., 2001, 836 p. (in Russian) 
21. Pankratova P.Ya. Lichinki i kukolki komarov podsemeistva Orthocladiinae fauny SSSR (Diptera, Chironomidae = Tendipedidae) [Larvae and pupae of Orthocladiinae subfamily in fauna of USSR (Diptera, Chironomidae = Tendipedidae)]. St.-Petersb., Nauka Publ., 1970, 344 p. (in Russian) 
22. Pankratova P.Ya. Lichinki i kukolki komarov podsem. Chironominae fauny SSSR (Diptera, Chironomidae = Tendipedidae) [Larvae and pupae of Chironominae subfamily in fauna of USSR (Diptera, Chironomidae = Tendipedidae)]. St.-Petersb., Nauka Publ., 1983, 295 p. (in Russian) 
23. Rukovodstvo po gidrobiologicheskomu monitoringu presnovodnykh ekosistem [Guidelines for hydrobiological monitoring of freshwater ecosystems]. St.-Petersb., Gidrometeoizdat Publ., 1992. 319 p. (in Russian) 
24. Tarakanova K.V., Matveev A.N., Samusenok V.P., Yur'ev A.L., Vokin A.I. Struktura zoobentosa nebol'shikh vysokogornykh ozer v verkhnem techenii r. Svetlaya (bassein Verkhnei Angary) [Structure of zoobenthos in small high-mountain lakes in the upper reaches of the Svetlaya River (Upper Angara basin)]. Raznoobrazie pochv i bioty Severnoi i Tsentral'noi Azii [Diversity of soils and biota of Northern and Central Asia: Proc. IV Allrus. Sci. Conf. Ulan-Ude, Russia]. Ulan-Ude : BuryatSC SB RAS Publ., 2021, pp. 457-459. (in Russian) 
25. Tomilov A.A. Materialy po gidrobiologii nekotorykh glubokovodnykh ozer Olekmo-Vitimskoi gornoi strany [Materials to hydrobiology of deep-water lakes of Olyokma-Vitim mountain area]. Trudy Irkutskogo gos. un-ta. Ser. biol. [Bul. Irkutsk St. Univ. Ser. Biol.]. 1954, vol. 11, pp. 1-86. (in Russian) 
26. Tarakanova K.V., Vokin A.I., Samusenok V.P., Yur'ev A.L., Matveev A.N. Kharakteristika makrozoobentosa oz. Amut (bassein r. Barguzin, Severnoe Zabaikal'e) [Characteristics of the macrozoobenthos of Lake Amut (Barguzin River basin, Northern Transbaikalia)]. Sovremennye problemy ekologii, gidrobiologii i baikalovedeniya [Modern problems of ecology, hydrobiology and Baikal studies: Proc. Int. Sci. Conf. Irkutsk, Russia]. Irkutsk, Irkutsk St. Univ. Publ., 2025, pp. 294-296. (in Russian) 
27. Tarakanova K.V. Raznoobrazie i struktura zoobentosa oz. Yakondykon (Amutskaya kotlovina, Severnoe Zabaikal'e) [Diversity and structure of zoobenthos of Lake Yakondykon (Amut Basin, Northern Transbaikalia)]. Sotsial'no-ekologicheskie problemy Baikalskogo regiona i sopredel'nykh territorii [Social and environmental problems of the Baikal region and adjacent territories: Proc. VI Allrus. Sci. Conf., Irkutsk, Russia]. Irkutsk, Irkutsk St. Univ. Publ., 2023, pp. 67-69. (in Russian) 
28. Khassan A.I. Kainozoiskie kompleksy osadochnykh otlozhenii v osevykh Barguzinskoi i Tunkinskoi dolinakh Baikal'skoi riftovoi sistemy [Cenozoic sedimentary complexes in the axial Barguzin and Tunka valleys of the Baikal rift system: Candidate in Geology dissertation]. Irkutsk, 2022, 207 p. (in Russian) 
29. Alimov A.F. Structural and Functional Characteristics of Aquatic Animal Communities. Hydrobiologia, 1991, vol. 76, is. 2, pp. 169-182. https://doi.org/10.1002/iroh.19910760203
30. Lindegaard C. The role of zoobenthos in energy flow in two shallow lakes. Hydrobiologia, 1994, vol. 275, pp. 313-322. https://doi.org/10.1007/BF00026722
31. Bailey R., Norris R., Reynoldson T. Bioassessment of Freshwater Ecosystems. Using the Reference Condition Approach. Kluwer Acad. Publ., 2004, 171 p. https://doi.org/10.1007/978-1-4419-8885-0
32. Handler A.M., Weber M., Dumelle M., Jansen L.S., Carleton J.N., Schaeffer B.A., Paulsen S.G., Barnum Th., Rea A.W., Neale A., Compton J.E. Ecological condition of mountain lakes in the conterminous United States and vulnerability to human development. Ecol. Indic., 2025, vol. 173, 113402. https://doi.org/10.1016/j.ecolind.2025.113402 
33. Bondarenko N.A., Sheveleva N.G., Rozhkova N.A., Matveev A.N., Samusenok V.P., Vokin A.I., Yuriev A.L. Remote mountain lakes of Eastern Siberia: a pattern of ecologically pure non-industrialised water-bodies. Environ. Earth Sci., 2017, vol. 76, 378. https://doi.org/10.1007/s12665-017-6708-4 
34. Machate O., Schmeller D. S., Schulze T., Brack W. Review: mountain lakes as freshwater resources at risk from chemical pollution. Environ. Sci. Eur., 2023, vol. 35, no. 3. https://doi.org/10.1186/s12302-022-00710-3 
35. Rieradevall M., Jimenez M., Prat N. The zoobenthos of six remote high mountain lakes in Spain and Portugal. Verh. Internal. Verein. Limnol., 1998, vol. 26, no. 4, pp. 2132-2136. https://doi.org/10.1080/03680770.1995.11901120 
36. Simčič T. The role of plankton, zoobenthos, and sediment in organic matter degradation in oligotrophic and eutrophic mountain lakes. Hydrobiologia, 2005, vol. 532, pp. 69-79. https://doi.org/10.1007/s10750-004-9015-5