Zooplankton and Dead Zooplankton in Kharbeyskie Lakes of Bolshezemelskaya Tundra (Period From 2009 to 2012)

В июле–августе 2009, 2010, 2012 гг. исследован состав и структура зоопланктона в системе Харбейских озер Большеземельской тундры. Обнаружено 87 видов и форм, из которых более половины коловратки (Rotifera). Планктонная фауна обследованных озер обычна для южных тундр и представлена азональными таксонами. Зоопланктон оз. Большой Харбей и придаточных озер различался по составу и количественным показателям, которые соответствовали различным уровням трофности экосистем. Межгодовая динамика планктонных сообществ в озерах была связана с динамикой погодных условий. Доминантный комплекс зоопланктона по численности в оз. Большой Харбей состоял из четырех, по биомассе – из девяти видов, был представлен эвпланктонными видами как коловраток, так и ракообразных (Cladocera, Copepoda) и слабо изменялся по годам. В небольших придаточных озерах число доминирующих в планктоне видов было меньшим по сравнению с оз. Большой Харбей, в глубоководных – доминантный комплекс был сходен с таковым в Большом Харбее. Не было выявлено достоверных различий в количестве зоопланктона в литорали и профундали основного озера системы. Пространственное распределение видов соответствовало морфологическим особенностям водоемов. В 2012 г. в основном и придаточных Харбейских озерах наблюдалась депрессия планктонных Copepoda, проявлявшаяся в высокой доле мертвых особей этих ракообразных в численности рачкового планктона. Наблюдали поражение микропаразитами (вероятно, грибковое) доминирующего вида – Heterocope appendiculata (Copepoda)Zooplankton composition and structure in Kharbeyskie Lakes system of Bolshezemelskaya tundra were investigated in July, August of 2009, 2010 and 2012. In total, 87 species and forms were found and more than half of them belonged to rotifers (Rotifera). Plankton fauna of the studied lakes was typical for southern tundra and presented by azonal taxa. Composition and abundance of zooplankton of Bolshoy Kharbey Lake and adjacent lakes were different and correspond to trophic conditions in ecosystems. Inter-annual dynamics of plankton communities in the lakes was determined by weather conditions. In Bolshoy Kharbey Lake four euplanktonic species of rotifers and crustaceans (Cladocera and Copepoda) dominated in terms of abundance and nine species dominated in terms of biomass. Inter-annual changes in dominant species composition were insignificant. In Bolshoy Kharbey Lake the number of dominant species were more than in the adjacent lakes. Differences in the abundance of zooplankton between littoral and prophundal zones of the main lake were not significant. Spatial distribution of species was determined by the morphology of the lakes. Depression of plankton copepods in the main and adjacent Kharbeyskie Lakes was observed in 2012 and proportion of dead individuals in crustacean communities was high. Probably it was related with mass infection of dominant species Heterocope appendiculata (Copepoda) by microparasite

Biogeographic patterns of planktonic and meiobenthic fauna diversity in inland waters of the Russian Arctic

Broad-scale assessment of biodiversity is needed for detection of future changes across substantial regions of the Arctic. Presently, there are large data and information gaps in species composition and richness of the freshwater planktonic and meiobenthos communities of the Russian Arctic. Analysis of these data is very important for identifying the spatial distribution and temporal changes in species richness and diversity of rotifers, cladocerans, and copepods in the continental Russian Arctic. We investigated biogeographic patterns of freshwater plankton and meiobenthos fromc. 67 degrees to 73 degrees N by analysing data over the period 1960-2017. These data include information on the composition of rotifers, cladocerans, and copepods obtained from planktonic and meiobenthic samples, as well as from subfossil remains in bottom sediments of seven regions from the Kola Peninsula in the west, to the Indigirka River Basin (east Siberia) in the east. Total richness included 175 species comprised of 49 rotifer genera, 81 species from 40 cladoceran genera, and 101 species from 42 genera of calanoid, cyclopoid, and harpacticoid copepods. Longitudinal trends in rotifer and micro-crustacean diversity were revealed by change in species composition from Europe to eastern Siberia. The most common and widespread species were 19 ubiquitous taxa that includedKellicottia longispina(Rotifera),Chydorus sphaericuss. lat. (Cladocera),Heterocope borealis,Acanthocyclops vernalis, andMoraria duthiei(Copepoda). The highest number of rare species was recorded in the well-studied region of the Bolshezemelskaya tundra and in the Putorana Plateau. The total number of copepod and rotifer species in both Arctic lakes and ponds tended to increase with latitude. Relative species richness of copepods was positively associated with waterbody area, elevation, and precipitation, while relative species richness of cladocerans was positively related to temperature. This result is consistent with known thermophilic characteristics of cladocerans and the cold tolerance properties of copepods, with the former being dominant in shallow, warmer waterbodies of some western regions, and the latter being dominant in large cold lakes and waterbodies of eastern regions. Rotifers showed a negative association with these factors. Alpha- and beta-diversity of zooplankton in the Russian Arctic were strongly related to waterbody type. Lake zooplankton communities were more diverse than those in pond and pool systems. Moreover, the highest beta-diversity values were observed in regions that showed a greater breadth in latitude and highly heterogeneous environmental conditions and waterbody types (Bolshezemelskaya tundra and Putorana Plateau). Redistribution of freshwater micro-fauna caused by human activities occurred in the 1990s and 2000s. As a result of climate warming, a few cladoceran species appear to have extended their range northward. Nevertheless, the rotifer and micro-crustacean fauna composition and diversity of the majority of Arctic regions generally remain temporally conservative, and spatial differences in composition and species richness are chiefly associated with the differences between the warmer European and colder east Siberian climates.Peer reviewe

First circumpolar assessment of Arctic freshwater phytoplankton and zooplankton diversity : Spatial patterns and environmental factors

Arctic freshwaters are facing multiple environmental pressures, including rapid climate change and increasing land-use activities. Freshwater plankton assemblages are expected to reflect the effects of these stressors through shifts in species distributions and changes to biodiversity. These changes may occur rapidly due to the short generation times and high dispersal capabilities of both phyto- and zooplankton. Spatial patterns and contemporary trends in plankton diversity throughout the circumpolar region were assessed using data from more than 300 lakes in the U.S.A. (Alaska), Canada, Greenland, Iceland, the Faroe Islands, Norway, Sweden, Finland, and Russia. The main objectives of this study were: (1) to assess spatial patterns of plankton diversity focusing on pelagic communities; (2) to assess dominant component of beta diversity (turnover or nestedness); (3) to identify which environmental factors best explain diversity; and (4) to provide recommendations for future monitoring and assessment of freshwater plankton communities across the Arctic region. Phytoplankton and crustacean zooplankton diversity varied substantially across the Arctic and was positively related to summer air temperature. However, for zooplankton, the positive correlation between summer temperature and species numbers decreased with increasing latitude. Taxonomic richness was lower in the high Arctic compared to the sub- and low Arctic for zooplankton but this pattern was less clear for phytoplankton. Fennoscandia and inland regions of Russia represented hotspots for, respectively, phytoplankton and zooplankton diversity, whereas isolated regions had lower taxonomic richness. Ecoregions with high alpha diversity generally also had high beta diversity, and turnover was the most important component of beta diversity in all ecoregions. For both phytoplankton and zooplankton, climatic variables were the most important environmental factors influencing diversity patterns, consistent with previous studies that examined shorter temperature gradients. However, barriers to dispersal may have also played a role in limiting diversity on islands. A better understanding of how diversity patterns are determined by colonisation history, environmental variables, and biotic interactions requires more monitoring data with locations dispersed evenly across the circumpolar Arctic. Furthermore, the importance of turnover in regional diversity patterns indicates that more extensive sampling is required to fully characterise the species pool of Arctic lakes.Peer reviewe

Integrative Analysis of Harpacticoid Copepod Fauna (Harpacticoida, Copepoda) in the South of Krasnoyarsk Krai: in Several Ergaki Nature Park Waterbodies and the Yenisei River

Фауна Harpacticoida Сибири изучена недостаточно. Впервые исследован состав фауны этих ракообразных нескольких водоемов на территории природного парка «Ергаки» и реки Енисей в черте города Красноярска, представлены данные по морфологии найденных видов и подвидов и их генетическим баркодам – нуклеотидным последовательностям фрагмента мтДНК СОI. В результате исследований в июле 2021 г. в природном парке «Ергаки» обнаружено шесть видов и подвидов ракообразных родов Pesceus, Bryocamptus, Maraenobiotus, Attheyella и Moraria; в Енисее найдены Maraenobiotus и Moraria, а также Harpacticella inopinata. Все таксоны обнаружены в пределах своих известных ареалов. Для пяти из них получены генетические баркоды, всего 25 последовательностей. Филогенетический анализ подтвердил генетическую близость H. inopinata и Attheyella nordenskioldii юга Красноярского края и озера Байкал (генетические дистанции 0,014–0,036), а также молекулярно-генетическую, но не морфологическую, однородность Maraenobiotus insignipes insignipes нескольких водоемов региона исследований (попарные генетические дистанции не превышали 0,008). Этот вид был наиболее распространенным на юге Красноярского края. Субэндемик озера Байкал H. inopinata был зарегистрирован только в Енисее. Полученные данные расширяют представления о фаунистическом, морфологическом и генетическом разнообразии Harpacticoida внутренних вод СибириThe crustacean fauna of Siberia, in particular the Harpacticoida, has not been studied sufficiently. For the first time, the composition of harpacticoid copepod fauna in several waterbodies in the Ergaki Nature Park and the Yenisei River near the city of Krasnoyarsk is examined, and the data on the morphology and genetic barcodes (nucleotide sequences of the mtDNA fragment COI) of the species and subspecies found are presented. In July 2021, six species and subspecies of harpacticoids of the Pesceus, Bryocamptus, Maraenobiotus, Attheyella and Moraria genera were found in the Ergaki Nature Park; Maraenobiotus, Moraria and Harpacticella inopinata were found in the Yenisei River. All taxa were found within the known distribution ranges. For five of them, genetic barcodes were obtained, a total of 25 sequences. A phylogenetic analysis confirmed the genetic closeness of H. inopinata and Attheyella nordenskioldii in the south of Krasnoyarsk Krai and Lake Baikal (genetic distances were 0.014–0.036), as well as molecular-genetic, but not morphological, homogeneity of Maraenobiotus insignipes insignipes from several waterbodies in the study site (pairwise genetic distances did not exceed 0.008). The latter species has been found the most common in the south of Krasnoyarsk Krai. H. inopinata, a subendemic of Lake Baikal, has been registered in the Yenisei River only. The data obtained broaden understanding of taxonomic, morphological and genetic diversity of the Harpacticoida fauna in Siberia’s inland water

Influence of the Water Level in the Yenisei River on the Ecosystem of its Anabranch within the City of Krasnoyarsk

Расположенная в черте города Красноярска в 35 км ниже Красноярской ГЭС Абаканская протока р. Енисей является, с одной стороны, важным рекреационным водоемом, а с другой стороны, подвержена нескольким типам антропогенного воздействия (зарегулирование дамбой, поступление ливневых и теплых вод, наличие садкового рыбоводного хозяйства), ухудшающего ее рекреационные свойства из-за чрезмерного зарастания макрофитами и скоплений метафитона нитчатой водоросли рода Spirogyra, ухудшения органолептических и микробиологических показателей воды. Природные климатические факторы способны существенно модифицировать влияние антропогенных факторов, что представляет интерес в плане прогнозирования и принятия решений по ликвидации негативных явлений. Целью работы является оценка влияния режима уровня воды р. Енисей в весенне-летний период на экосистему протоки через сравнение данных в многоводный (2021) и средневодный (2020) годы. Гидрофизические, гидрохимические и гидробиологические измерения проводили с мая по август 2020 и 2021 гг. сверху вниз на станциях левобережья: 1 – выше дамбы (фон), 2 – ниже дамбы, 3 – напротив выпуска теплых вод ТЭЦ, 4 – пляж, ниже рыбоводных садков. В 2021 г. вода в протоку поступала только снизу (к ст. 4 и 3), так как водопропускные трубы в теле плотины были засыпаны. В 2021 г., по сравнению с 2020 г., на зарегулированном участке протоки значительно увеличились численность и биомасса фито- и зоопланктона, возросла первичная продукция планктона, а аналогичные показатели фитоперифитона и зообентоса, напротив, снизились по причине их формирования на свежезалитых грунтах. Метафитон отсутствовал, но в августе спирогира стала доминировать в биомассе фитоперифитона. Концентрации нитрит-иона в воде увеличились в зарегулированной части протоки, а нитрат-иона и общего фосфора – на всех станциях протоки, в том числе и на фоновой, получающей воды из Красноярского водохранилища. Наблюдаемая в 2021 г. «вспышка трофии» в планктоне ст. 3 и 4 обусловлена длительным (полтора месяца) удержанием высокого уровня воды в протоке, позволившим использовать биоте вымываемые из затопленных берегов органические вещества и биогены, и аналогична таковой в экотонных зонах выклинивания подпора водохранилищ. Ежегодное увеличение концентраций минеральных форм азота и общего фосфора на нижних станциях, по сравнению с другими станциями, вероятно, обусловлено эвтрофирующим влиянием садкового рыбоводного хозяйстваLocated within the city of Krasnoyarsk, 35 km downstream of the Krasnoyarsk Hydropower Plant, the Abakanskaya anabranch of the Yenisei River, on the one hand, is an important recreational water body and, on the other hand, is subject to several types of anthropogenic impact (regulation by a dam, inflow of storm and warm waters, fish farming). These impacts worsen its recreational properties due to excessive growth of macrophytes and metaphytic filamentous algae of the genus Spirogyra, causing deterioration of organoleptic and microbiological parameters of water. Natural climatic factors can significantly modify the influence of anthropogenic factors, which is of interest in terms of forecasting and decision-making about the elimination of negative factors. The aim of the present work is to assess the influence of the water level regime of the Yenisei River in the spring–summer period on the anabranch ecosystem by comparing the data for the high-water (2021) and medium-water (2020) years. Hydrophysical, hydrochemical, and hydrobiological measurements were carried out from May to August 2020 and 2021 at locations on the left bank: 1 – upstream of the dam (reference), 2 – downstream of the dam, 3 – opposite the outlet of warm water, 4 – at the beach, downstream of the fish farm. In 2021, water entered the anabranch only from downstream (to locations 4 and 3), since the culverts in the dam body were filled up. In 2021, compared to 2020, the abundance and biomass of phyto- and zooplankton in the regulated section of the anabranch significantly increased, the primary production of plankton increased, but the corresponding parameters of phytoperiphyton and zoobenthos, on the contrary, decreased due to their formation on freshly flooded soils. Metaphyton was absent, but in August, Spirogyra began to dominate in the phytoperiphyton biomass. Nitrite ion concentrations in the water increased in the regulated part of the anabranch, and the nitrate ion and total phosphorus concentrations increased at all locations, including the reference location, receiving water from the Krasnoyarsk Reservoir. The plankton “abundance outbreak” observed in 2021 at locations 3 and 4 was caused by the water level in the anabranch remaining high over a long period (one and a half months), which made it possible for the biota to use organic matter and nutrients washed out from the flooded banks; the outbreak was similar to those occurring in the ecotone zones of inputs to the upper parts of reservoirs. The annual increase in the concentrations of mineral forms of nitrogen and total phosphorus at the lower locations compared with other locations was probably due to the eutrophic influence of fish farmin

Evaluation of Possible Causes of Non-Predatory Mortality of Crustacean Zooplankton in a Small Siberian Reservoir

Non-predatory specific mortality (NPSM) of dominant zooplankton species, Daphnia (longispina group) and Cyclops vicinus, was estimated during 1997-2000 sampling seasons on the basis of a new direct method: live/dead sorting and sediment trap measurements. Simultaneously measured ecological factors, such as water temperature, pH, dissolved oxygen, biomass of cyanobacteria, diatoms, greens and euglens, levels of polyunsaturated fatty acids of ω3 family, α-linolenic (ALA) and eicosapentaenoic (EPA), were considered as possible causes of the mortality using multivariant canonical correlation analysis. Toxicity was discarded on the basis of another set of study of the reservoir. As found, the best predictor of Daphnia mortality was EPA level, negatively correlated with NPSM value. Nevertheless, large part of variance of Daphnia mortality and practically all variance of Cyclops NPSM remain unexplained and need future investigation

Evaluation of Possible Causes of Non-Predatory Mortality of Crustacean Zooplankton in a Small Siberian Reservoir

Non-predatory specific mortality (NPSM) of dominant zooplankton species, Daphnia (longispina group) and Cyclops vicinus, was estimated during 1997-2000 sampling seasons on the basis of a new direct method: live/dead sorting and sediment trap measurements. Simultaneously measured ecological factors, such as water temperature, pH, dissolved oxygen, biomass of cyanobacteria, diatoms, greens and euglens, levels of polyunsaturated fatty acids of ω3 family, α-linolenic (ALA) and eicosapentaenoic (EPA), were considered as possible causes of the mortality using multivariant canonical correlation analysis. Toxicity was discarded on the basis of another set of study of the reservoir. As found, the best predictor of Daphnia mortality was EPA level, negatively correlated with NPSM value. Nevertheless, large part of variance of Daphnia mortality and practically all variance of Cyclops NPSM remain unexplained and need future investigation

Evaluation of Abundance of Dead Crustacean Zooplankton in a Water Body Using Staining of the Samples by Aniline Blue Technique: Methodological Aspects

Для проверки предположения, что по мере переработки тканей мертвой особи микроорганизмами-гетеротрофами интенсивность окрашивания трупов планктонных ракообразных анилиновым голубым уменьшается, провели три длительных эксперимента по определению скорости разложения трупов и изменению окраски по мере их разложения с убитыми нагреванием копеподитами циклопов (Cyclops vicinus, Mesocyclops leuckarti, эксперименты 1, 2), циклопами и дафниями разного размера и стадий (C. vicinus, Daphnia группы longispina, эксперимент 3). Кроме того, была проведена методическая работа по окрашиванию живых рачков, только что травмированных механически, для имитации возможных механических повреждений зоопланктеров при отборе проб и выявления характера их окрашивания. Эксперименты показали, что чем сильнее зеселен труп микрогетеротрофами, тем менее интенсивно он окрашивается. В зависимости от температуры окружающей воды и морфологических особенностей кладоцер и копепод (открытые створки и относительно тонкая кутикула у дафний, более прочный и замкнутый панцирь у циклопов) «возраст» трупа рачка, когда он перестает окрашиваться из-за сильной переработки своих тканей микрогетеротрофами, определяется как 1-4 суток от момента гибели. Напротив, полностью и интенсивно окрашивается мертвая особь, умершая в интервале 1 час – 1-3 суток до отбора и окрашивания пробы. Механически травмированные живые особи окрашиваются не полностью: либо только по месту травмы, либо больше, но обычно не более 1/2 или 2/3 всего тела. Для повышения точности учета мертвых особей в пробах из водоема с использованием метода окраски анилиновым голубым даны соответствующие методические рекомендации.Three long special experiments with killed by heating copepodites of Cyclops vicinus, Mesocyclops leuckarti (experiments 1 and 2), of Cyclops vicinus and Daphnia longispina group of different sizes and stages (experiment 3) were carried out to test an assumption that in proportion as decomposition and losses internal tissues of dead plankton crustaceans (by microorganisms-heterotrophs consumption), ability of dead tissues to take up stain Aniline blue and the intensity of their coloration are reduced. Besides, the methodical work on staining mechanically traumatized alive crustaceans was carried out to imitation of possible consequences of body injuries during zooplankton sampling and study of characteristics of their staining. The experiments have shown the more heterothrophes inside the dead carcasses, the less intensity of its staining. Depending on water temperature and morphological features of cladocerans and copepods, an “age” of dead crustaceans when it stops successfully stain is 1-4 days from death time. On the contrary carcasses of crustaceans, which dead during time interval “one hour – 1-3 days” are stained intensity and entirely. Mechanically traumatized alive crustaceans are stained not entirely, just spot of injury or more, but no more than one half or 2/3 of body. To increase accuracy of count of dead zooplankton in nature samples using Aniline blue staining method, suitable (proper) methodological recommendation are given

Evaluation of Abundance of Dead Crustacean Zooplankton in a Water Body Using Staining of the Samples by Aniline Blue Technique: Methodological Aspects

Для проверки предположения, что по мере переработки тканей мертвой особи микроорганизмами-гетеротрофами интенсивность окрашивания трупов планктонных ракообразных анилиновым голубым уменьшается, провели три длительных эксперимента по определению скорости разложения трупов и изменению окраски по мере их разложения с убитыми нагреванием копеподитами циклопов (Cyclops vicinus, Mesocyclops leuckarti, эксперименты 1, 2), циклопами и дафниями разного размера и стадий (C. vicinus, Daphnia группы longispina, эксперимент 3). Кроме того, была проведена методическая работа по окрашиванию живых рачков, только что травмированных механически, для имитации возможных механических повреждений зоопланктеров при отборе проб и выявления характера их окрашивания. Эксперименты показали, что чем сильнее зеселен труп микрогетеротрофами, тем менее интенсивно он окрашивается. В зависимости от температуры окружающей воды и морфологических особенностей кладоцер и копепод (открытые створки и относительно тонкая кутикула у дафний, более прочный и замкнутый панцирь у циклопов) «возраст» трупа рачка, когда он перестает окрашиваться из-за сильной переработки своих тканей микрогетеротрофами, определяется как 1-4 суток от момента гибели. Напротив, полностью и интенсивно окрашивается мертвая особь, умершая в интервале 1 час – 1-3 суток до отбора и окрашивания пробы. Механически травмированные живые особи окрашиваются не полностью: либо только по месту травмы, либо больше, но обычно не более 1/2 или 2/3 всего тела. Для повышения точности учета мертвых особей в пробах из водоема с использованием метода окраски анилиновым голубым даны соответствующие методические рекомендации.Three long special experiments with killed by heating copepodites of Cyclops vicinus, Mesocyclops leuckarti (experiments 1 and 2), of Cyclops vicinus and Daphnia longispina group of different sizes and stages (experiment 3) were carried out to test an assumption that in proportion as decomposition and losses internal tissues of dead plankton crustaceans (by microorganisms-heterotrophs consumption), ability of dead tissues to take up stain Aniline blue and the intensity of their coloration are reduced. Besides, the methodical work on staining mechanically traumatized alive crustaceans was carried out to imitation of possible consequences of body injuries during zooplankton sampling and study of characteristics of their staining. The experiments have shown the more heterothrophes inside the dead carcasses, the less intensity of its staining. Depending on water temperature and morphological features of cladocerans and copepods, an “age” of dead crustaceans when it stops successfully stain is 1-4 days from death time. On the contrary carcasses of crustaceans, which dead during time interval “one hour – 1-3 days” are stained intensity and entirely. Mechanically traumatized alive crustaceans are stained not entirely, just spot of injury or more, but no more than one half or 2/3 of body. To increase accuracy of count of dead zooplankton in nature samples using Aniline blue staining method, suitable (proper) methodological recommendation are given

Data on taxa composition of freshwater zooplankton and meiobenthos across Arctic regions of Russia

We present the presence/absence species list (Table 1) of rotifer, cladoceran, and copepod (Calanoida, Harpacticoida, and Cyclopoida) fauna from seven Arctic regions of Russia (the Kola Peninsula, the Pechora River Delta, the Bolshezemelskaya tundra, the Polar Ural, the Putorana Plateau, the Lena River Delta, and the Indigirka River Basin) based on our own and literature data. Our own records were obtained by analyzing samples of zooplankton, meiobenthos, and two cores of bottom sediments (from the Kola Peninsula and the Bolshezemelskaya tundra lakes) that we collected once in July or August in 1992, 1995–2017. To supplement the list, we used relevant literature with periods of research from the 1960s to the 2010s. The list is almost identical to “Dataset 2: Zooplankton and Meiofauna across Arctic Regions of Russia”, which was analyzed but not published in [1]. The detailed analysis of this list revealed the specific composition of the aquatic fauna associated with the climatic and geographical factors [1]. The data provide information on the current state of biodiversity and species richness in Arctic fresh waters and can serve as the basis for monitoring these environments and predicting how they are likely to change in the future