ISSN 1995-4255, Contemporary Problems of Ecology, 2017, Vol. 10, No. 4, pp. 350–362. © Pleiades Publishing, Ltd., 2017. Chironomid Fauna of the Lakes from the Pechora River Basin (East of European part of Russian Arctic): Ecology and Reconstruction of Recent Ecological Changes in the Region1 L. B. Nazarovaa, b, c, *, A. E. Selfd, S. J. Brooksd, N. Solovievae, f, L. S. Syrykh c, g, **, and V. A. Dauvalterh aPotsdam University, Institute of Earth and Environmental Science, Potsdam-Golm, 2514476 Germany bAlfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Research Unit Potsdam, Potsdam, 14473 Germany cKazan Federal University, Kazan, 420008 Russia dThe Natural History Museum, London, UK eEnvironmental Change Research Centre, University College London, London WC1H 0AP, UK fHigher Colleges of Technology, Sharjah, UAE, PO BOX 7947 gHerzen State Pedagogical University of Russia, St. Petersburg, 191186 Russia hInstitute of the North Industrial Ecology Problems KSC RAS Apatity, Akademgorodok, 184209 Russia *e-mail: [email protected] **e-mail: [email protected] Received October 19, 2016; in final form, January 25, 2017 Abstract⎯We investigated chironomid fauna of surface sediments and a short sediment core (Bol’shoy Khar- bey Lake) from Pechora river basin, Northern Russia. Twenty three investigated lakes have thermokarst, gla- cial or floodplain origin and are characterised by low mineralization, mostly hydrocarbon-calcium type of water and low concentration of nutrients. Most of the lakes have circumneutral pH around ≤7 and only two lakes are slightly more acidic with pH ≤ 6. Ninety six chironomid taxa were identified in the surface sedi- ments. Distribution of chironomids in the studied region is driven by continentality, mean TJuly and рН. Chi- ronomid communities from the core of the B. Kharbei Lake demonstrate the highest similarity with the fauna of the deeper lakes of the glacial origin. The glacial lakes have the highest indices of continentality and the lowest winter temperatures within the investigated data set. The chironomid fauna of the glacial lakes is com- posed of the profundal, oligotrophic and cold-stenotherm taxa. The fauna of the floodplain and thermokarst lakes is more closely related to TJuly and is composed of littoral and phytophilic taxa of meso – or eutrophic waters and moderate temperature conditions. The fauna of the acidic thermokarst lakes considerably differs from the other lakes. Chironomid communities here are represented by tolerant to acidification taxa, and by the typically littoral and shallow water acid-tolerant taxa that apparently also can tolerate acidification. Stud- ied sediment record covers ca last 200 years. The reconstructed TJuly during the entire period remain slightly below the modern temperatures. From 1970 reconstructed TJuly shows steady increase to the modern level. The reconstructed water depths (WDs) of the lake are higher than today till 1980. The highest WDs are recon- structed for ca 1970. After that the WDs gradually decrease to the modern level. Changes of the WDs are most probably related to changes in the precipitation rate. Keywords: river Pechora basin, lakes, chironomids, temperature, depth, continentality, Russian Arctic DOI: 10.1134/S1995425517040059 INTRODUCTION entire spectrum of life strategies of the most important Arctic regions are sensitive to global climate change indicator group of benthic communities, which and the arctic waters are excellent indicators of the include heterotrophic chironomids, is essential for global temperature rise on the planet. The, arctic lake assessment of the ecological state of surface waters and communities are particularly vulnerable to intensive for exploration of natural successions under the influ- industrial development, which makes studies of Arctic ence of natural and anthropogenic factors (Zinchenko, lakes and their biota especially important (Frolova 2011; Kondrateva et al., 2014). et al., 2014). Long-term studies of aquatic communi- Studies of the lakes from Canadian Arctic, Scandi- ties may reveal dynamics of aquatic ecosystem navia and Fennoscandia showed that the changes in responses to global climate change. Knowledge of the their ecosystems are largely linked to global warming during the last 150–200 years (Smol et al., 2005). 1 The article is published in the original. However, there are only few recent studies which 350 CHIRONOMID FAUNA OF THE LAKES FROM THE PECHORA RIVER BASIN 351 30° 40° 50° 60° 70° 80° 1 F3-2 2 F3-3 3 F3-5 Yamal 70° 4 F3-6 Barents sea Penisula 5 F3-12 6 F4-2 7 F4-4 8 F4-5 9 F6-2 22 6–8 1–5 21 13 10 F7-3 14 Bol’shoy Kharbey L. 11 F7-4 17 19 10–12 12 F7-5 Usa R. 13 F8-2 20 15 16 14 F8-4 Pechora R. 18 15 TDRA_2 16 TDRC_2 9 17 TDRD_2 18 TDRE_1 19 TDRU11a Russia 20 TDRU_42a 21 Mitro 40° 50° 60° 0 150 300 450 km 22 Vanuk-ty Fig. 1. Location of the investigated lakes. investigated environmental changes in lakes from skaya tundra and surrounding areas of the River north-east of the European Russia (e.g. Solovieva Pechora basin; (2) to identify environmental factors et al., 2005, 2008; Nazarova et al., 2014; Palagushkina affecting distribution of chironomid taxa in the et al., 2014). region, and ecological features of the common chi- Chironomid larvae have many advantages as indi- ronomid taxa; (3) qualitative and quantitative recon- cator organisms. Quick development and generations struction of the environmental conditions in the change, wide range of ecological adaptations and high region during the last ca 200 years using chironomid sensitivity allows them rapidly respond to changing sediment record from the Bol’shoi Kharbey Lake, environment and make it possible to use them for eval- Bolshezemelskaya tundra; (4) validation of the uation and interpretation of environmental changes obtained quantitative reconstructions. with a high degree of confidence (Brooks et al., 2007). Chironomids are indicative of eutrophication, MATERIALS AND METHODS acidification, toxic pollution and other chemical and physical changes in the environment, and their head- Bol’shoi Kharbei Lake is located in the Pechora capsules are well-preserved in sediments remains of River basin (north-east of the European Russia, Fig. 1), their head capsules are widely used in paleoecology which flows through Bolshezemelskaya, Malozemel- (Brooks and Birks, 2000; Massaferro and Brooks, skaya tundras to the south of the Arctic Circle through 2002; Solovieva et al., 2005; Kienast et al., 2011). a coniferous taiga. The climate of the region is subarc- Chironomid larvae are the most widespread and tic with long and cold winters, which lasts up to large group of zoobenthos of freshwaters (Nazarova 8 months, and minimum temperatures going below et al., 2004; Epler, 2001). In the lakes of the eastern ‒50°C in January. Summer is short and cool. The part of European Russian Arctic chironomids consti- warmest month is July (New et al., 2002) with the tute up to 100% of the benthic communities (Kuz- mean temperatures ranging from 8 to 12°C (Mukhin mina, 2001; Loskutova, 2002; Baturina et al., 2012; et al., 1964). The average annual precipitation varies Kondrateva et al., 2014). At the same time, ecology of from 370 to 395 mm (Mukhin et al., 1964). chironomids in the region still remains poorly studied 22 lakes were sampled between 1998 and 2001 within and their application in palaeoclimatic studies is spo- the framework of interdisciplinary international Euro- radic (Solovieva et al., 2005; Nazarova et al., 2014). pean projects TUNDRA (TUNdra Degradation of The aim of our study is to reconstruct recent palae- Russian Arctic, 1998–2001, http://www.ib.komisc.ru/ oecological conditions in the Bolshezemelskaya tun- en/international-scientific-cooperation/1088-tundra) dra using chironomid-based statistical models and and SPICE (Solovieva et al., 2002, 2005). Samples data on the chironomid ecology in the region. In par- were selected along 4 transects crossing the major ticular, the research focused on the following: (1) to industrial centers of the region: Vorkuta (transect 1), study chironomid fauna of the lakes of Bolshezemel- Inta (transects 2 and 3) and Usinsk (transect 4). Some CONTEMPORARY PROBLEMS OF ECOLOGY Vol. 10 No. 4 2017 352 NAZAROVA et al. Table 1. Names of the lakes from Pechora basin, their main geographical and climatic parameters. ТJuly—mean July air temperature, °C, ТJanuary—mean January air temperature, °C, СI—Gorczynski continentaliy index. Temperatures and CI are calculated by New et al., (2002). Lake origin: g—glaciar, f—floodplain, t—thermokast Altitude Water Т Т Lakes Latitude, N Longitude, E S, ha СI Origin (m, asl) depth, m July, °C January, °C F3-2* 67.93 54.03 13 4.3 11 13.3 –19.1 39 f F3-3* 67.93 54.05 20 1.5 26 13.3 –19.1 39 t F3-5* 67.92 54.03 17 3.3 12 13.3 –19.1 39 f F3-6* 67.93 54.00 18 1.3 28 13.3 –19.1 39 t F3-12* 67.95 53.93 13 2.8 13 13.3 –19 39 f F4-2* 68.00 52.38 4.8 6 40 12.9 –18.3 37 f F4-4* 68.00 52.45 72 1.1 38 12.9 –18.3 37 t F4-5* 68.00 52.40 72 1.1 45 12.9 –18.3 37 g F6-2* 64.32 59.08 225 15 4 14.6 –22.4 49 g F7-3* 67.12 56.68 75 0.7 0.1 14 –20.4 43 t F7-4* 67.12 56.72 78 1 14 14 –20.4 43 t F7-5* 67.13 56.68 82 2.5 0.5 14 –20.4 43 f F8-2 67.87 59.72 23 3.5 0.2 12.9 –21.4 43 t F8-4* 67.88 59.67 15 6 0.1 12.9 –21.4 43 g TDRA 2* 65.98 60.02 59 6.6 36 14.6 –21.7 47 g TDRC 2* 66.10 60.25 50 1.7 135 14.6 –21.7 47 g TDRD 2* 67.12 59.57 110 5.2 42 13.2 –21.7 44 g TDRE 1* 65.25 59.67 514 17 6 11.6 –24.8 48 g TDRU11a 67.45 63.08 60 1.7 44 12.8 –23.8 47 g TDRU 42a* 65.97 57.27 116 8.7 43 15.5 –20.4 46 g Mitrofanovskoe 67.85 58.98 132 20 31 12.5 –21.5 42 g Vanuk-Ty 68.00 62.75 124 25 830 12.6 –23.3 45 g Bol’shoy Kharbey 67.53 62.88 100 18 2130 12.9 –23.6 46 g * Lakes do not have official names and in our article we use the field codes.