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Purpose. Investigate ecological conditions and determine fish productivity of ponds when growing young-of-the-year carp using a suspension of chlorella. Methodology. During the study, we used methods generally accepted in hydrochemistry, hydrobiology and fish farming. Findings. The article presents the results of the study on the use of chlorella suspension in the cultivation of carp. It was found that the use of chlorella suspension created favorable hydrochemical conditions resulting in intensive development of zooplankton, which had a positive effect on the growth of young-of-the-year carp and fish productivity of the pond. The development of the natural food supply was sufficient to meet the nutritional needs of juvenile carp. The average seasonal biomass of zooplankton in the experimental pond was 28.68 g/m3 that was 1.5 times higher than in the control. The share of cladocerans in the total biomass of zooplankton in the experimental pond was 76.6%, versus 36.8% in the control. The average biomass of zoobenthos for the growing season in the experimental was 1.3 times higher than in the control, and was formed by chironomid larvae, which are valuable in the food chain. Originality. The study investigated ecological conditions and fish productivity of growing ponds under conditions of the application of cattle manure and suspension of chlorella when growing carp in monoculture. Practical value. It was found that the use of chlorella suspension promotes the intensification of the development of zooplankton organisms in ponds. The obtained data can be used to develop practical recommendations for optimizing the conditions for growing carp seeds and increasing the biological productivity of ponds. Key words: nursery ponds, natural food supply, phytoplankton, zooplankton, zoobenthos, young-of-the-year carp, chlorella suspension, fish productivity.

Gut microbiota is closely related to the health of the host and its adaptation to environmental changes. Sinopotamon planum is a species of freshwater crab that lives in the water for three seasons and plays a key role in freshwater ecosystems as a benthic macroinvertebrate, an important indicator of aquatic ecological health. In this study, we sequenced 60 gut microbial samples of S. planum and nine microbial samples from the surrounding water in spring, summer, and autumn based on the 16S rRNA gene. The results showed that gut microbiota had the highest alpha diversity in summer, which may be related to increased adaptability in summer. Firmicutes, Proteobacteria, and Bacteroidota were the most dominant phyla of gut microbiota across three seasons, with Candidatus Hepatoplasma and Candidatus Bacilloplasma being the main genera. These main phyla and genera may be key to maintaining a stable function of the intestinal environment. Firmicutes was the phylum with the highest relative abundance, which is probably related to the carnivorous behaviour of S. planum. The abundant C. Hepatoplasma may be related to the starvation of S. planum in the wild. In both gut and water microbiota, beta diversity analyses showed significant differences across seasons. Comparative analysis of gut microbes and surrounding water microbes showed significant differences in microbial diversity and composition between gut and surrounding water. In conclusion, the structure of the gut microbial community of S. planum differed significantly between the studied seasons, but the water microbial community around S. planum was less variable and significantly different from the gut microbes. The seasonal differences in gut microbes are more likely the result of self-internal adaptation to changes in water temperature and food resources between seasons.

The goal of this investigation was to assess the role of a number of environmental variables on the traits of a peracarid population inhabiting turfs of Ellisolandia elongata in a Mediterranean disturbed location. Samples were collected from a vertical and a horizontal surface to assess the role of orientation, and several structural traits of the turf (number of fronds, their height and width, available phytal area for colonization, and dry weight) were measured. The samples were characterized by their species composition, relative abundance of constant species, total abundance of individuals, and α-diversity (species richness, Shannon index and Pielou’s evenness). Generalized linear models were used to relate environmental variables with ecological descriptors, whereas a cluster plot and a principal correspondence analysis, both based on the Bray-Curtis coefficient, were conducted to detect the presence of distinct assemblages. Results showed orientation to be a key factor governing the assemblages, since samples from vertical and horizontal surfaces formed definite groups based on Bray-Curtis similarities. Moreover, GLMs pointed out that orientation influenced relative abundance of the majority of constant species, as well as species richness and Shannon index. Phytal height had a positive effect on the relative abundances of Hexapleomera bultidactyla, Coxischyrocerus inexpectatus and Hyale stebbingi, and a negative one on Shannon index and evenness, whereas available phytal area influenced positively evenness and negatively the relative abundance of Elasmopus pocillimanus. Thus, it can be inferred that although species composition depended on surface orientation, the spatial structure of the turf was the main driver for assemblage complexity, Partial fnancial support was received from the Spanish Ministry of Science and Innovation [Research Project “Polychaeta VI: Palpata-Canalipalpata I (CGL2014-53332-C5-3-P)”]

Purpose. To investigate the peculiarities of the formation of hydrochemical, hydrobiological regimes and to determine the fish productivity of nursery ponds under a complex exposure to their ecosystem. Methodology. The work was conducted according to generally accepted hydrochemical, hydrobiological and aquaculture methods. Findings. The article presents the results of the study on the productivity of nursery ponds when using a complex of intensification measures (fertilization with traditional fertilizers, application of chlorella paste, polyculture, and fish feeding). It was found that the main hydrochemical parameters during the rearing of cyprinid fingerlings were within the standard normal values ​​and were favorable for the development of prey organisms and the cultivation of fish seeds. Positive trends were obtained after the use of chlorella paste when growing juveniles of cyprinids in polyculture with different ratios of common carp and Chinese carps. The use of the chlorella paste in combination with other intensification measures in the experimental ponds created favorable conditions for the development of natural food supplies, growth and survival of cyprinid fingerlings. At the same time, the total fish productivity in the experimental ponds was 22.0-28.0% higher, and the feed costs were 1.1-1.3 times lower than in the control ponds. Originality. The peculiarities of the formation of hydrochemical and hydrobiological regimes have been investigated and the fish productivity of nursery ponds has been determined using cattle humus and chlorella pasta when growing young-of-the-year carp in polyculture with silver and bighead carp hybrids. Practical value. The obtained data can be used for developing practical recommendations regarding the optimization of the conditions for growing cyprinid seeds in polyculture using the chlorella pasta, increasing the efficiency of managing the state of aquatic ecosystems and their biological productivity.

The paucity of data on non-indigenous marine species is a particular challenge for understanding the ecology of invasions and prioritising conservation and research efforts in marine ecosystems. Marenzelleria spp. are amongst the most successful non-native benthic species in the Baltic Sea during recent decades. We used stable isotope analysis (SIA) to test the hypothesis that the dominance of polychaete worm Marenzelleria arctia in the zoobenthos of the Neva Estuary after its invasion in the late 2000s is related to the position of this species in the benthic food webs. The trend towards a gradual decrease in the biomass of Marenzelleria worms was observed during 2014–2020, probably due to significant negative relationships between the biomass of oligochaetes and polychaetes, both of which, according to SIA, primarily use allochthonous organic carbon for their production. The biomass of benthic crustaceans practically did not change and remained very low. The SIA showed that, in contrast to the native crustacean Monoporeia affinis, polychates are practically not consumed either by the main invertebrate predator Saduria entomon, which preys on M. affinis, oligochaetes and larvae of chironomids or by benthivorous fish that prefer native benthic crustaceans. A hypothetical model for the position and functional role of M. arctia in the bottom food web is presented and discussed. According the model, the invasion of M. arctia has created an offshoot food chain in the Estuary food webs. The former dominant food webs, associated with native crustaceans, are now poorly developed. The lack of top-down control obviously contributes to the significant development of the Marenzelleria food chain, which, unlike native food chains, does not provide energy transfer from autochthonous and allochthonous organic matter to the upper trophic levels. The study showed that an alien species, without displacing native species, can significantly change the structure of food webs, creating blind offshoots of the food chain.

1. Growing bioeconomy is increasing the pressure to clear-cut drained peatland forests. Yet, the cumulative effects of peatland drainage and clear-cutting on the biodiversity of recipient freshwater ecosystems are largely unknown. 2. We studied the isolated and combined effects of peatland drainage and clear-cutting on stream macroinvertebrate communities. We further explored whether the impact of these forestry-driven catchment alterations to benthic invertebrates is related to stream size. We quantified the impact on invertebrate biodiversity by comparing communities in forestry-impacted streams to expected communities modelled with a multi-taxon niche model. 3. The impact of clear-cutting of drained peatland forests exceeded the sum of the independent effects of drainage and clear-cutting, indicating a synergistic interaction between the two disturbances in small streams. Peatland drainage reduced benthic biodiversity in both small and large streams, whereas clear-cutting did the same only in small streams. Small headwater streams were more sensitive to forestry impacts than the larger downstream sites. 4. We found 11 taxa (out of 25 modelled) to respond to forestry disturbances. These taxa were mainly different from those previously reported as sensitive to forestry-driven alterations, indicating the context dependence of taxonomic responses to forestry. In contrast, most of the functional traits previously identified as responsive to agricultural sedimentation also responded to forestry pressures. In particular, taxa that live temporarily in hyporheic habitats, move by crawling, disperse actively in water, live longer than 1 year, use eggs as resistance form and obtain their food by scraping became less abundant than expected, particularly in streams impacted by both drainage and clear-cutting. 5. Synthesis and applications. Drained peatland forests in boreal areas are reaching maturity and will soon be harvested. Clear-cutting of these forests incurs multiple environmental hazards but previous studies have focused on terrestrial ecosystems. Our results show that the combined impacts of peatland drainage and clear-cutting may extend across ecosystem boundaries and cause significant biodiversity loss in recipient freshwater ecosystems. This information supports a paradigm shift in boreal forest management, whereby continuous-cover forestry based on partial harvest may provide the most sustainable approach to peatland forestry.

Purpose. Creation of a thematic bibliographic list of publications on the use of classical and modern methods for studying the biota of water bodies - bacterio-, phyto-, zooplankton, zoobenthos, higher aquatic plants. Methods. The complete and selective methods were applied in the process of the systematic search. The bibliographic core have been formed with the publications exclusively in Ukrainian and Russian from the fund of scientific library of the Institute of Fisheries NAAS of Ukraine. Results. A thematic list of publications with a total quantity of 150 sources covering the time interval from 1949 to 2017, and devoted to the development and application of methods for studying aquatic biocenoses, their individual components and productive characteristics has been composed. The literary sources are arranged in alphabetical order by author or title, and described according to DSTU 8302:2015 “Information and documentation. Bibliographic reference. General principles and rules of composition”, with the amendments (code UKND 01.140.40), as well as in accordance with the requirements of APA style — international standard of references. Practical value. The list may be useful for scientists, practitioners, students, whose area of interests covers the questions of hydrobiology, hydroecology, zoology and aquaculture.

The rate at which biological diversity is altered on both land and in the sea, makes temporal community development a critical and fundamental part of understanding global change. With advancements in trait‐based approaches, the focus on the impact of temporal change has shifted towards its potential effects on the functioning of the ecosystems. Our mechanistic understanding of and ability to predict community change is still impeded by the lack of knowledge in long‐term functional dynamics that span several trophic levels. To address this, we assessed species richness and multiple dimensions of functional diversity and dynamics of two interacting key organism groups in the marine food web: fish and zoobenthos. We utilized unique time series‐data spanning four decades, from three environmentally distinct coastal areas in the Baltic Sea, and assembled trait information on six traits per organism group covering aspects of feeding, living habit, reproduction and life history. We identified gradual long‐term trends, rather than abrupt changes in functional diversity (trait richness, evenness, dispersion) trait turnover, and overall multi‐trait community composition. The linkage between fish and zoobenthic functional community change, in terms of correlation in long‐term trends, was weak, with timing of changes being area and trophic group specific. Developments of fish and zoobenthos traits, particularly size (increase in small size for both groups) and feeding habits (e.g. increase in generalist feeding for fish and scavenging or predation for zoobenthos), suggest changes in trophic pathways. We summarize our findings by highlighting three key aspects for understanding functional change across trophic groups: (a) decoupling of species from trait richness, (b) decoupling of richness from density and (c) determining of turnover and multi‐trait dynamics. We therefore argue for quantifying change in multiple functional measures to help assessments of biodiversity change move beyond taxonomy and single trophic groups., In this study, we identified gradual long‐term trends in functional diversity, trait turnover, and overall multi‐trait community composition spanning a period of 40 years and two key trophic groups: fish and zoobenthos, in three coastal marine areas. The study highlights the need for multiple measures and cross‐trophic level assessments to understand empirical functional (trait) change and serves as a baseline for functional change in the Baltic Sea region and other coastal and estuarine ecosystems worldwide. The findings contribute to the general understanding of biodiversity change and can be useful for developing predictions and models of community change.

Understanding the impact of the environment on temporal trends in the composition and abundance of deep-sea species is essential for forecasting evolution of the community in the context of climate change. The recent development of deep-sea observatories enables multidisciplinary studies of long duration and high temporal resolution. We used a platform at the Ocean Networks Canada NEPTUNE Observatory located in the axis of Barkley Canyon between June 2012 and January 2015 to: (1) characterize the megabenthic community and the environmental conditions in the canyon; (2) investigate temporal patterns in the faunal community; and (3) determine the influence of environmental conditions on the observed patterns. The megafaunal epibenthic community, which included commercially important species, was composed of species known to be able to adapt to low oxygen conditions. A strong seasonal pattern characterized wind speed and direction, wave height, temperature, and chlorophyll concentration at the sea surface. The megafaunal epibenthic community exhibited seasonal patterns which were influenced by in-situ benthic boundary layer currents and temperature, weather conditions and chlorophyll concentration at the sea surface. At inter-annual scales, the surface temperature anomaly event observed in 2013 in the region could potentially impact the community structure with significant changes in species’ densities, highlighting the need for long-term monitoring in the region.

Studies of the benthos in nearshore water areas within Protected Areas along the Black Sea are an important ecological task. In this connection, protected habitats can be recognised as intact natural areas, where the entire natural complex is preserved with its typical taxonomic structure and biodiversity features. This study is based on the obtained quantitative data on the biodiversity of benthic assemblages in coastal Protected Areas. It aims to study the structure of polychaete communities as inhabitants of fouling areas at sublittoral (depth 0–3 m) rocky/boulder substrates in four Protected Areas along the Black Sea (Cape Martyan State Nature Reserve, Karadag State Nature Reserve, Opukskiy State Nature Reserve, and Utrish State Nature Reserve). The studied sites differ in their geographic location, orographic shape of the coastal strip, features of underwater substrates, the pattern of spatial coverage and species composition of macroalgae foulings and other environmental parameters. The purpose of this study was also to make a prognostic estimation of the expected species richness (Sexp) and comparative analysis of the structural organisation of polychaete complexes on rocky substrates in the selected coastal Protected Areas. The prognostic modelling of polychaete species richness was based on the known extrapolation algorithms (estimators Chao-2, Jackknife-2, and bootstrap). The results show that the expected level of species richness (Sexp) exceeds the actually detected (Sobs) number of species in each of the four Protected Areas by 20–95%, depending on the estimator and total number of collected samples. In all sublittoral water areas, it was found that with an increase in the number of samples the accumulation curves do not reach a horizontal asymptote. This indicates an underestimated species richness of polychaetes. At the rocky sublittoral zone of the Cape Martyan State Nature Reserve, the fastest increase in Sexp values was revealed with an increase in the number of samples taken. This relationship can be determined by heterogeneity of microhabitats in this area, where the increased number of polychaete species is also formed. Considering the other Protected Areas, the extrapolative curves of species richness have a flatter mode and a smaller expected number of species (Sexp), despite the larger number of samples analysed. According to the results of the clustering and ordination analyses, based on the species composition and abundance of polychaetes, almost all samples taken were grouped into separate clusters corresponding to each of the four studied Protected Areas. The reliability of structural differences between polychaete complexes was statistically confirmed by pairwise comparison of three areas (Utrish, Karadag, and Martyan). The comparison of sites conditionally named Utrish and Opukskiy demonstrated that structural differences between polychaete complexes were statistically insignificant probably due to the affinity of the geomorphologic pattern of hard-bottoms and composition of fouling vegetation in sublittoral zones of both Protected Areas. The specific polychaete complexes have been formed on rocky/boulder substrates within each of the investigated Protected Areas, being different in their taxonomic structure and quantitative characteristics of the certain species. For each polychaete complex, the most significant species were identified, which determine both the intracomplex taxonomic structure (indicating species) and structural differences between the complexes (discriminating species). In the polychaete complex of the rocky sublittoral in the Karadag State Nature Reserve such indicating species were Nereis zonata, Platynereis dumerilii, and Syllis gracilis. In the Cape Martyan State Nature Reserve and Utrish State Nature Reserve, the indicating taxa were Polyophthalmus pictus, Nereis sp., and Pholoe inornata. Finally, in the Opukskiy State Nature Reserve, Notomastus latericeus and Pholoe inornata were recognised as indicating species. Most of these species may also be considered as discriminating species. Parameters of their quantitative development reflect the structural features of polychaete complexes formed under the influence of specific environmental factors in the sublittoral zone of each of the four studied coastal Protected Areas. The obtained results of the structural-faunistic analysis of polychaete complexes can be applied for comparative assessment of the biodiversity features of benthic communities during the comprehensive ecological monitoring of the coastal Protected Areas.

Background. The study of the fish feed base of the Khatanga River is necessary due to the fact that the river is used for commercial fishing of valuable fish species. The last description of the communities of zooplankton and zoobenthos of the Khatanga River was carried out according to the data of 1946, respectively, there is no more up-to-date information about the state of hydrobiological communities. The aim of this work is to establish the taxonomic composition and quantitative characteristics of zooplankton and zoobenthos communities, as well as to assess the trophic status of the Khatanga River. Materials and methods. Studies of the river were conducted at 5 stations: in 2014-in the areas of the settlements of Novorybnoye and Kresty, in 2015-at 25 km, 45 km and 67 km from the mouth of the river, in 2018-2020-in the area of the settlement of Khatanga. Samples of zooplankton and zoobenthos were collected and processed according to the methods generally accepted in Russian hydrobiology. All samples were taken in three repetitions. Results, conclusions. During the 2014–2015 and 2018– 2020 studies, 33 taxa were identified in zooplankton, and 37 in zoobenthos. The average values of zooplankton abundance and biomass ranged from 57±57 to 477±441 ind./m3 and from 0.52±0.52 to 3.12±0.64 mg/m3, respectively, and zoobenthos – from 260 to 2642 ind./m2 and from 0.65 to 4.04 g/m2, respectively. Rotifers were dominant in the zooplankton community in terms of quantitative parameters, while chironomids, oligochaetes, and mollusks were dominant in the zoobenthos. According to the development of zooplankton and zoobenthos, the river belongs to the "low-feed" fishing facilities. The trophic category of the Khatanga River is defined as "ultra – oligotrophic" by zooplankton, and "α-mesotrophic" by zoobenthos.

В рамках данной работы рассматриваются результаты мониторинговых исследований, проводимых специалистами ООО «Азово-Черноморский научный центр рыбохозяйственных исследований» в период января-декабря 2020 г. по изучению видового состава и численности организмов зообентоса на периодически затапливаемых участках акватории Краснодарского края в пределах ст-цы Старокорсунская Краснодарского края В результате исследований изучено видовое разнообразие, получены сезонные и годовые показатели численности и биомассы организмов зообентоса на периодически затапливаемых участках акватории Краснодарского водохранилища. Проведена сравнительная характеристика данных характеристик с показателями, характерными для постоянно обводненных участков акватории Краснодарского водохранилища., Within the framework of this work, the results of monitoring studies carried out by specialists of the Azov-Chernomorsk Scientific Center for Fisheries Research in the period January-December 2020 to study the species composition and number of zoobenthos organisms in periodically flooded areas of the Krasnodar Territory water area within the Starokorsunskaya station are considered. Krasnodar Territory. As a result of the research, the species diversity was studied, seasonal and annual indicators of the abundance and biomass of zoobenthos organisms were obtained in periodically flooded areas of the Krasnodar reservoir. A comparative characteristic of these characteristics with the indicators typical for constantly watered areas of the Krasnodar reservoir is carried out.

High-elevation tropical lakes are excellent sentinels of global change impacts, such as climate warming, land-use change, and atmospheric deposition. These effects are often correlated with temporal and spatial beta diversity patterns, with some local communities contributing more than others, a phenomenon known as local contribution to beta diversity (LCBD) or ecological uniqueness. Microorganisms, such as diatoms, are considered whole-ecosystem indicators, but little is known about their sensitivity and specificity in beta diversity studies mostly because of the lack of large spatial and temporal datasets. To fill this gap, we used a tropical South American diatom database comprising modern (144 lakes) and paleolimnological (6 sediment cores) observations to quantify drivers of spatial and temporal beta diversity and evaluated implications for environmental change and regional biodiversity. We used methods of beta diversity partitioning (replacement and richness components) by determining contributions of local sites to these components (LCBDrepl and LCBDrich), and studied how they are related to environmental, geological, and historical human variables using Generalized Additive Models (GAM). Beta replacement time series were also analyzed with GAM to test whether there is widespread biotic homogenization across the tropical Andes. Modern lake ecological uniqueness was jointly explained by limnological (pH), climatic (mean annual precipitation), and historical human density. Local lake (conductivity) and regional geodiversity variables (terrain ruggedness, soil variability) were inversely correlated to replacement and richness components of LCBD, suggesting that not all lakes contributing to broad-scale diversity are targets for conservation actions. Over millennial time scales, decomposing temporal trends of beta diversity components showed different trajectories of lake diatom diversity as response of environmental change: i) increased hydroclimatic variability (as inferred by decreased temperature seasonality) mediating higher contribution of richness to local beta diversity patterns ca. 1000 years ago in Ecuador Andean lakes and ii) lake-specific temporal beta diversity trends for the last ca. 200 years, indicating that biotic homogenization is not widespread across the tropical Andes. Our approach for unifying diatom ecology, metacommunity, and paleolimnology can facilitate the understanding of future responses of tropical Andean lakes to global change impacts.

Concentration of neurotoxin Hg (mercury) was determined monthly form 01.2012 to 05.2013 (total and suspended) in the surface microlayer and the surface water as well as in: phytoplankton, zooplankton, epilithon, epifithon, phytobenthos (macroalgae and angiosperms), zoobenthos, and in the sediment. The study was conducted in the coastal zone of the Puck Lagoon (Osłonino and Chałupy) and the Gulf of Gdańsk (Gdynia). Mercury data were compiled with the abundance and biomass of individual species of: phytoplankton, phytobentos, zoobenthos; abundance of individual species of zooplankton; water temperature; salinity; pH; suspended particulate matter concentration; concentration of particulate organic carbon and nitrogen (in the surface microlayer and the surface water); δ13C and δ15N in the suspended matter; sediment parameters like: moisture, fine sediment fraction, LOI and redox condition. Results indicate influence of warming of cold season (from late autumn to early spring) on Hg concentration in biotic and abiotic components of marine coastal zone. Increase annual average mercury concentration in trophic web of gulf.

The results of long-term complex hydrobiological studies of the cooling pond of the South Ukrainian Nuclear Power Plant (SU NPP) are presented. The abundance of zoo- and phytoplankton increased until 1984–1985, and then in the summer of 1986, against a background of extremely high temperatures in the reservoir, there was a significant (32-fold) drop in the mean biomass of phytoplankton, coinciding with the minimum abundance of zooplankton. In subsequent years, the abundance of these groups recovered, but has not reached previous levels. At present, the zooplankton contains a considerable amount of thermophilic species. Research in recent years indicates that the zooperiphyton is dominated by the invasive gastropods Melanoides tuberculata (Müller, 1774) and Terebia granifera (Lamarck, 1822). In the epiliton, the number of LDT (lowest determined taxa) and groups of invertebrate was more than double that in the epiphyton (17 and 7, respectively). At the first stages of the development of the pond ecosystem, the periphyton communities were dominated by zebra mussel Dreissena polymorpha Pall. These communities were eliminated as temperature increased, and after the commissioning of the NPP, the second and third power units were not completely restored in the environment of a constantly high thermal load. Over years, with the formation of bottom biotopes, the abundance of zoobenthos increased, and with an increase in the technogenic load, it decreased. At the present stage, the zoobenthos is impoverished (9 taxa) and is dominated by mainly juvenile tubificids.

В статье представлены результаты изучения влияния антропогенных факторов городской агломерации на жизнь зообентоса озер Белое, Сайсары, Теплое, Талое, Хатынг-Юрях, Сергелях и Атласовские Якутска. Показано, что городские озера различаются между собой по видовому разнообразию. Максимальное число видов с численностью 184 экз/м2 и биомассой 40,24 г/м2 определено в озере Белое. Основными систематическими группами в исследуемых озерах были пиявки, бокоплавы и хирономиды (67 %), которые относятся к организмам умеренно-загрязненных и грязных вод. Результаты исследования зообентоса озера Хатын — Юрях, расположенный на северо-восточной части Якутска, определили как с бедной бентофауной, всего тремя систематическими группами организмов — пиявки, бокоплавы и личинки двукрылых. Массовыми по численности оказались бокоплавы (236 экз/м2), а по биомассе пиявки (22,08 г/м2). При этом большинство организмов относились к трем классам качества вод, а состояние озер оценили как — «чрезвычайно грязное». Нами определенный анализ состояния зообентоса городских озер указывает об устойчивом антропогенном воздействии города Якутска на экосистемы всего бассейна в целом., The article presents the results of teaching the studies of the impacts of anthropogenic factors of agglomeration on the life of the zoobenthos of the lakes Beloe, Saisary, Teploe, Taloe, Khatyng-Yuryakh, Sergelyakh and Atlasovskie in Yakutsk. It is shown that these urban lakes differ in their types of diversity. The maximum number of species with a number of 184 ind./m2 and a biomass of 40.24 g/m2 was found in Lake Beloe. The main systematic groups in the studied lakes were polluted leeches, amphipods and chironomids (67 %), which belong to the organisms of moderately polluted and dirty waters. The results of the study of the zoobenthos of Lake Khatyn — Yuryakh, located in the northeastern part of the city of Yakutsk, were identified as having a poor benthic fauna: only 3 systematic groups of organisms, i.e. leeches, amphipods and dipteran larvae. Amphipods (236 ind./m2) turned out to be massive in terms of numbers, and leeches in terms of biomass (22.08 g/m2). Moreover, most of the organisms belonged to three classes of water quality, and the state of the lakes was assessed as “extremely dirty”. We have determined that the analysis of the state of the zoobenthos in urban lakes indicates a stable anthropogenic impact of the city of Yakutsk on the ecosystems of the entire basin as a whole.

Представлен обзор опубликованных материалов о влиянии вселенца Dreissena polymorpha Pallas на экосистему Нарочанских озер (Беларусь). Показана динамика развития популяции моллюска-вселенца в озерную экосистему, его роль в составе малакофауны и значимость как средообразующего фактора. Оценен вклад дрейссены в круговорот взвешенных, органических и биогенных веществ и влияние моллюска на ранний диагенез донных отложений.

The life cycle parameters of the benthic invertebrate Chironomus riparius make it a relevant organism for use in multi-generation chronic ecotoxicology tests. Since studies on chronic exposures with fullerene carbon nanoparticles have revealed adverse effects at lower concentration ranges, it is crucial to gain understanding of the consequences in following generations. The aims of this study were to investigate whether sediment-associated fullereneC 60 impacts on C. riparius emergence and breeding, thus affecting the growth of the second generation. Larvae were exposed to fullerene-spiked sediment at concentrations of 0.5, 10 and 40 mg/kg sediment dw. Total emergence and breeding success were monitored after the first generation and the newly hatched larvae from the first generation exposure were transferred either to continuous exposure or to pristine sediment without fullerene. Findings indicate that the presence of fullerenes has major impacts on the first generation, mainly shown as delayed emergence time of females. Increased larval growth was observed in the second generation, and we conclude that the C. riparius response to fullerene exposure indicated significant signs of recovery in second-generation larval growth. The result shows the effects to be important for population dynamics, revealing delayed female emergence time, which leads to situation where adults’ breeding is impaired.

Purpose. To investigate the effect of the bacterial fertilizer "Phosphobacterin" on the formation of the hydrochemical regime, development of the natural food supply and fish productivity in the growing ponds. Methodology. The work was conducted according to generally accepted hydrochemical,, microbiological, hydrobiological and fish farming methods. Findings The article presents the results of a study of the productivity of growing ponds with different methods of the application of the bacterial fertilizer "Phosphobacterin". It was found that the hydrochemical regime of the experimental ponds was formed under the effect of the source of water supply and measures aimed at intensifying the development of the natural food supply and was favorable for the development of feed organisms and the cultivation of fish seeds. Application of the bacterial fertilizer at the beginning of the growing season along the water pond surface proved to be little effective for increasing the productivity of the pond ecosystem as a whole. A more effective method of increasing biological productivity, including fish productivity of growing ponds, was the application of "Phosphobacterin" during the growing season both on the bed and on the water surface in combination with the organic fertilizer - cattle humus. In the experimental pond under complex fertilization, the average phytoplankton biomass during the growing season was 1.5 times, bacterioplankton 1.1 times, zoobenthos 2.6 times higher, and the obtained total fish productivity was 1.2 times higher than in the control pond (when applying only cattle humus). Originality. The peculiarities of formation of hydrochemical and hydrobiological (phyto-, bacterio-, zooplankton, zoobenthos) regimes of growing ponds and the fishery indices are studied, both for bacterial fertilizer "Phosphobacterin" independently and together with the traditional organic fertilizer - cattle humus. Practical value. Based on the obtained results, we developed temporary recommendations for using the bacterial fertilizer "Phosphobacterin" to increase the productivity of growing ponds.

By studying 14 travertine-depositing springs all over Austria, we hypothesized the existence of (1) key elements of the physical and chemical template ultimately defining the structure of macroinvertebrate taxa composition and (2) a specific, travertine-associated macrozoobenthic taxa community in an environment shaped by ongoing deposition of calcium carbonate and the ever-changing limestone structures thereby created. For testing these hypotheses, we measured 29 geological and limnochemical parameters and collected benthic macroinvertebrates on travertine, coarse and fine particular organic matter microhabitats in a spring and autumn sampling run. The results identified four parameters significantly shaping taxa composition: sinter coverage, total phosphorous, oxygen concentration and the Langelier saturation index. The macroinvertebrate community was predominantly composed of stygobiontic taxa from groundwater refugia and of immigrated generalists that prefer the stable conditions offered in spring habitats. We found only few species and specialists separating study sites, the majority being well-known spring- and headwater-dwelling species without adaptation to high carbonate precipitation or association with travertine. Nonetheless, carbonate precipitation leads to higher structural heterogeneity and provides a range of new niches, which contribute to broader ranges of taxonomic diversity.

Species composition and abundance of zooplankton and zoobenthos of large Norilsk Lakes (Lama, Sobach’e) and Kutaramakan Lake in the western part of the Putorana plateau were studied in August-September of 2013–2014 after a long gap. Senecella calanoides Juday (Copepoda: Calanoida) in zooplankton and 5 species of water mites (Acalyptonotus violaceus Walter, Hygrobates (Hygrobates) foreli (Lebert), Lebertia (Mixolebertia) densa Koenike, Lebertia (Pilolebertia) porosa Thor, Oxus (Gnaphiscus) setosus (Koenike) (Hydrachnidia)) in zoobenthos were recorded for the first time in the investigated lakes. A total of 64 taxa of benthic invertebrates were found, of which 42 taxa were Chironomidae. Zooplankton species composition of Lama and Cobach’e lakes was similar and differed from that of Kutaramakan lake by presence of Senecella calanoides and Limnocalanus macrurus Sars (Copepoda: Calanoida). In zoobenthos of Kutaramakan lake amphipods were not found. Lama and Kutaramakan lakes can be classified as ultraoligotrophic water bodies based on biomass of zooplankton and zoobenthos. Among the studied lakes, Cobach’e lake has the greatest biomass, and based on the biomass of zooplankton in some zones of > 0.5 g/m3, it is an oligotrophic water body, and based on an average biomass of zoobenthos 3.85 g/m2 an α-mesotrophic one

WOS: 000401585900014, The invasive alien mytilid species, Brachidontes pharaonis, forms a biogenic habitat in the mediolittoral and upper-infralittoral zones of the Levantine Sea, hosting a number of alien and native species. Examinations of samples taken from dense, continuous mussel beds at seven stations along the coast of northern Levantine Sea yielded 187 macro-benthic invertebrate species belonging to 11 taxonomic groups. Polychaeta accounted for 46% and 37% of the total number of species and individuals, respectively. The top three dominant species in the mussel beds were Stenothoe gallensis, Spirobranchus kraussi and Mytilaster minimus. The species with the highest frequency values on the mussel beds were Pseudonereis anomala, Phascolosoma stephensoni and Elasmopus pocillimanus. The highest density and biomass of the associated fauna were estimated as 42,550 ind m(-2) and 1503 wwt g m(-2), respectively. The species number in samples varied between 14 and 47 species. The environmental variables best explaining variations in zoobenthic community structures were salinity, dissolved oxygen and total inorganic nitrogen in the water column. The biotic indices, TUBI and ALEX, classified the ecological status of one or two stations as moderate or poor, based on the relative abundances of ecological and zoogeographic groups, respectively. A total of 21 alien species were found to be associated with the mussel bed, of which Syllis ergeni is being newly considered as a new established alien species for the Mediterranean Sea. The maximum density of associated alien species was calculated as 30,300 ind m(-2). The alien species assemblages were greatly affected by salinity and total inorganic nitrogen., TUBITAK [104Y065], This work was financially supported by TUBITAK (Project Number: 104Y065).

Purpose. To study food resources, feeding conditions and trophic relationships of the brown trout (Salmo trutta morpha fario), rainbow trout (Oncorhynchus mykiss), and European grayling (Thymallus thymallus) in a Transcarpatioan river. Methodology. The material on the food resources and feeding of the brown trout, rainbow trout, and European grayling was collected in summer period of 2012 on the Shypit river. The study was performed on two different sites of the river: the first one was located on the middle pre-mountain reach of the river (upstream of the Hydroelectric power plant), the second one – on the mountain reach of the river (near tourist base) on typical biotopes: I – with boulders and riffles with fast current; II – with medium size stones and low riffles with moderate current; III – with small stones, sand and slow current. The material was collected and processed according to standard and unified hydrological, ichthyological, and trophological methods. Findings. We studied the level of macrozoobenthos development and obtained data on feeding and trophic relationships among brown trout, rainbow trout, and European grayling on different biotopes on pre-mountain and mountain reaches of the Shypit river. The number of “soft” macrozoobenthos on different biotopes varied from 972 to 2576 ind./m2 with biomasses from 6.3 to 121.8 g/m2. Total diet overlap index (DOI) between brown trout and rainbow trout on the biotope with boulders and fast current in the pre-mountain reach was 32.4% by number and 20.3% by biomass, while that on the mountain reach was 49.6% and 52.9%, respectively. On the biotope with medium size stones and moderate current, the diet overlap index between rainbow trout and European grayling in the pre-mountain reach was 19.0% by number and 27.9% by biomass. Originality. First study of the diet and tropic relationships of the brown trout, rainbow trout, and еuropean grayling on different reached of the Shypit river. Practical value. The results of this work can be used when calculating the amounts of brown trout, rainbow trout, and European grayling to be stocked into rivers of the Transcarpathian region.

Structural and functional characteristics of zoobenthos in two lakes with different trophic status and the level of human impact were investigated in spring, summer and autumn 2013 and 2014. Species composition, degree of dominance, trophic structure, production and a role in the decomposition of organic matter were studied in zoobenthos of the two lakes. Seasonal dynamics of the quantitative characteristics of zoobenthos in lakes with varying anthropogenic impact showed an asynchronous response of the communities on dynamics of natural factors

During a long-term study (2003-2007) of the chironomids in Vaya Lake 27 taxons were established. There were determined 18 species belonged to 11 genera. These results were compared to the only ones so far provided by Zashev and Angelov 1958. There is a complete change in the species composition of the Chironomidae compared with the results obtained in the period 1953-1957, which is mainly related to the increased anthropogenic impact on the lake and the changed connection with the Black Sea.

Título del Pre Print: "Annelid assemblages on artificial hard substrata differ from those on natural rocky shores after decades for colonization: A case study on a century old seawall in Western Mediterranean", Although strong differences have been observed between the assemblages on artificial substrata and on natural hard-bottom habitats, little is known about the mechanisms that cause them. The purpose of this study was to examine the differences in Mediterranean low shore annelid assemblages dwelling on an old artificial, vertical hard substratum and a natural, horizontal one. The structure of the Ellisolandia elongata turfs covering the two habitats showed little divergence in terms of length and number of thalli, as well as in available space for epibionts. In this respect, colonization duration might explain the lack of significant dissimilarities in the phytal canopy. In spite of this, statistical analyses showed that the specific composition of the two annelid assemblages differed in a significant manner. Although they shared a set of constant species, their relative abundances were dissimilar and this was especially evident for several species belonging to families Syllidae and Enchytraeidae. Abundance and species richness were significantly higher on natural structures, as expected, but Shannon diversity and equitability indexes were lower. Apparently, the sciophilous condition of vertical surfaces, which do not occur naturally in the area, is the main driver of the differences in species composition and its capital importance remains after colonization processes have occurred, This work was partially funded by the project “Polychaeta VI: Palpata-Canalipalpata I (CGL2014-53332-C5-3-P)” provided by Comisión Interministerial de Ciencia y Tecnología

Macroinvertebrates of stygobiotic origin contributing to benthic assemblages in springs of the two regions of West Transcaucasia were investigated. The regions concerned, basins of the Khosta­Kudeps­ ta Rivers (Krasnodarskiy krai) and Myussera Upland (Abkhazia), are well­studied and drastically different in a number of features. Frequency of occurrence, abundance and the position of stygobiotic species in the structure of crenal assemblages are given. Stygobionts dominated in 50% of cases, more often in helocrenes with variable runoff than in rheocrenes stably connected with watercourses. Stygo­ and crenobiotic primary aquatic invertebrates (crustaceans and mollusks) demonstrate pronounced local endemism at the species level. Under certain circumstances spring assemblages can be considered as island ones.

Increasing environmental pressures and human impacts are reshaping community structures and species interactions throughout all trophic levels. The morphological and behavioural characteristics of species communities contain key ecological information on why prey species appear attractive to predators but are rarely applied when exploring predator-prey (PP) relationships. Expanding our knowledge on how changing prey communities can alter the food resource suitability (RS) for predators is vital for understanding PP dynamics in changing ecosystems. Detailed predator diet data are commonly restricted to commercially important species and often not available over long temporal scales. To find out whether structural changes of prey communities impact the food RS for predator communities over space and time, we apply a novel framework to describe and interpret changes in predator diet-suitability based on predation-relevant traits of prey. We use information on described feeding links from the literature to compile the prey spectrum for each predator and subsequently translate the prey-species into a prey-trait spectrum. For each predator, we then calculate a frequency-based prey-trait affinity score and relate it to the available food resource pool, the community weighted means of prey traits, resulting in a prey-suitability measure. We aim to reveal whether a described multi-decadal change in the community structure of zoobenthos had an impact on the food suitability for the benthic-feeding fish in a coastal system of the Baltic Sea. We assess the direction of change in resource quality from the perspective of benthic-feeding fish and describe predator-specific responses to examine which species are likely to profit or be disadvantaged by changes in their prey spectrum. Furthermore, we test the relationship between functional diversity of prey communities and food suitability for predators, and whether predation linkage-structures are affected through prey community-changes. Our results show that changes in zoobenthic communities had a positive effect on the food suitability for most benthic-feeding fish, implying more suitable food resources. Species-specific responses of predators suggest varying plasticity to cope with prey assemblages of different trait compositions. Additionally, the functional diversity of zoobenthos had a positive effect on the food suitability for predator fish. The changing trait compositions of prey influenced the PP linkage-structure, indicating varying specialisation of benthic feeding fish towards available food resources. Our findings suggest that changing morphological characteristics of prey can impact food RS features for its predators. This approach enables long-term evaluation of prey quality characteristics where no detailed diet data is available and allows for cross-system comparison as it is not relying on taxonomic identities per se.

The lagoon of El Bibane (Tunisia) is a Mediterranean coastal area that is affected by an increasing human impact. Thus, an estimation of its biodiversity and an ecological quality assessment are very urgent. This study investigates the meiofaunal and nematode communities of the El Bibane lagoon both from a taxonomic and a functional point of view. Nematodes were the dominant group as is common in brackish water systems. The nematode community was made up of 62 genera in 22 families. Xyalidae, Chromadoridae and Cyatholaimidae were the richest and most abundant families. The taxonomic composition and biodiversity of nematodes were comparable to those found in other European and Mediterranean transitional areas. Both meiofauna and nematodes showed a clear subdivision between marginal and central areas. The central stations, represented by fine sediments and higher amounts of organic carbon, seemed to be characterized by low meiofaunal densities, nematode diversity and a strong dominance of 1B and 2B trophic guilds. These trends could be related not only to the grain size and organic load, but also to a possible influence of tidal currents that can transport pollutants in the central area of the lagoon coming from the adjacent coastal areas. Shannon diversity and life strategies are not always in agreement in defining the ecological quality, but an overall worse ecological quality was detected especially at S6. The results of this study are an important starting point for the future monitoring of the potential and actual human impact on the El Bibane area over time.

A large silver deposit Mangazeyskoe at the headwaters of the Yana River basin in North-East Yakutia has a considerable impact on vulnerable ecosystems of Alpine tundra. In the case of inadequate environmental protection measures, adverse environmental consequences may occur. The particular interest is the hydrobiological status of the rivers affected by the mining production waste water. In this regard, quantitative and qualitative baselines for water pollution indicators were studied. For the first time, preliminary data on the species composition of algae in the phytoplankton, phytoperiphyton, and zoobenthos of the watercourses at the Mangazeyskoe deposit. In the algal flora of reservoirs in the area of the Mangazeyskoe deposit, 230 identified species have been as represented by 260 intraspecific taxa, including those represented by a nomenclature type from 8 divisions. In the zoobenthos of the area under study, 28 species and forms belonging to three types have been found: annelids, arthropods and mollusks. It has been determined that the main part of the species of zoobenthos belongs to amphibiotic insects, which accounts for more than 70%. It has been noted that the current studied background condition of algae and zoobenthos in the area of the deposit consists mainly of cryophilic species.

Deep-sea sponge aggregations are widely recognised as features of conservation interest and vulnerable marine ecosystems that may particularly require protection from the impact of commercial bottom trawl fishing. In 2011 we revisited deep-sea sponge aggregations in the Porcupine Seabight (NE Atlantic, c. 1200 m water depth) originally described by Rice, Thurston and New (1990, Prog. Oceanogr. 24: 179-196) from surveys in 1983/4. Using an off-bottom towed camera system, broadly comparable to the bottom-towed system originally employed, we resurveyed four key transects detailed in that publication. In the intervening years, there has been a substantial increase in deep-water fishing activity; our primary objectives were therefore to establish the continued presence of Pheronema carpenteri (Hexactinellida, Pheronematidae), the current status of the sponge population, and whether there was any evidence of bottom trawl fishing impact on the sponges and their associated fauna. We noted a very substantial reduction in the standing stock of sponges: in Rice et al.'s (loc. cit.) peak abundance depth range (1210 – 1250 m) numerical density declined from 1.09 to 0.03 ind m-2, and biomass density from 246 to 4 gwwt m-2, between the surveys. Our assessment of available vessel monitoring data suggested that commercial bottom trawling had been occurring in the area, with some indication of focussed effort in the sponge's bathymetric range. We also recorded the presence of multiple apparent seafloor trawl marks on two of the transects. Despite the potential disturbance, the presence of sponge aggregations continued to exert a statistically significant positive influence on the diversity of the local megafaunal assemblage. Similarly, faunal composition also exhibited a statistically significant trend with P. carpenteri numerical density. Megafaunal numerical density, particularly that of ascideans, appeared to be enhanced in the core of Rice et al.'s (loc. cit.) peak abundance depth range potentially reflecting the residual effect of sponge spicule mats. Our observations were suggestive of a substantive impact by bottom trawl fishing; however, a definitive assessment of cause and effect was not possible, being hampered by a lack of temporal studies in the intervening period. Other causes and interpretations were plausible and suggested the need for: (i) a precautionary approach to management, (ii) an improved understanding of sponge natural history, and (iii) temporal monitoring (e.g. seafloor sponge habitat cover).

In late July 2018, we studied the chemical composition of the water and benthic communities in two hydrogen sulfide springs in the catchment of the Iska-Shor Creek (lefthand tributary of the Usa River), as well as zoobenthos and plankton in the Usa River around the creek’s mouth. Compared to the reference site, water in the springs contained manyfold higher concentrations of chlorine, sodium, calcium, sulfate ions, and differed in the content of organic matter, heavy metals, and several micro elements. Water temperature did not exceed +6 °С. Zoobenthos abundance and biomass was low, comprising31 taxa of invertebrates. Chironomid larvae and harpacticoids prevailed. Chironomids were the most diverse group in the creek – 20 taxa, of which 17 were found directly in the springs. Tanytarsus verralli Goetghebuer, 1928 was the most numerous species. Apart from chironomids, we found nematodes, ostracods, cladocerans, first instar larvae of mayflies, stoneflies and caddisflies, and others Dipteran families. The diversityof planktic and benthic invertebrates, and the set of dominant species showed little variation among the sites surveyed in the Usa River. The dominants in terms of abundance in the river’s benthic fauna were chironomid species from the subfamily Chironomini: Tanytarsus verralli, Cladotanytarsus (Cladotanytarsus) mancus (Walker, 1856), and Polypedilum (Pentapedilum) exsectum (Kieffer 1916). The share of roundworms decreased and the share of cyclops and water mites increased in the zoobenthos of the river downstream from the mouth of the creek. Among zooplankton dominants, the abundance of Euchlanis dilatata Ehrenberg, 1832 decreased and the share of Cladocera from the genus Bosmina increased downstream the river. Inside the area directly affected bythe mineral water springs, we found a high abundance of euplanktic rotifers Asplanchna priodonta Gosse, 1850 and copepods Mesocyclops leuckarti (Claus, 1857), as well asan increased abundance of juvenile Cyclopoida. The studies have expanded our knowledge of the adaptive capabilities of invertebrates, and the ecology of aquatic communities forming in this extreme environment.

Marine ecosystems worldwide are affected by both natural variation and human activities; to disentangle and understand their individual role in influencing the macrobenthic community composition is challenging. The relationship between interannual variability in atmospheric circulation, dictated by the climatic oscillation indices, and the benthic macrofauna composition was assessed at four sampling sites located in the Bay of Banyuls‐sur‐Mer (NW Mediterranean Sea). Between 2004 and 2013, these sites were sampled annually during autumn/winter and analyzed for sediment grain‐size and benthic macrofauna composition (species richness, abundance, and biomass). Temporal changes in these descriptors were correlated with two climatic indices (NAO and WeMO indices) and a set of environmental parameters integrated over three different time periods (i.e., whole year, springtime, and wintertime). Our results confirm the occurrence of major temporal changes in the composition of macrobenthic communities within the Gulf of Lions. More specifically, the results indicate that (a) the WeMO appears to be more closely related to benthic macrofauna composition in the Bay of Banyuls‐sur‐Mer than the NAO, (b) winter is a better integration period than spring or the whole year as a proxy for community composition changes, and (c) Rhône River water flow is likely involved in the control of benthic macrofauna composition in the whole Gulf of Lions. The present study highlights the importance of WeMO as a regional proxy, which can be used to evaluate changes in benthic macrofauna linked to climatic variability., This study is the first which establishes a relationship between a recent and regional climatic oscillation (WeMO) and benthic macrofauna communities. The results show responses to climate changes in all ecological levels (individual species to community level) based on 10‐year series.

Представлены результаты исследования видового состава зообентоса некоторых озер Виштынецкой группы. Произведена оценка экологического состояния озер с использованием индивидуальных индексов сапробности донных организмов, биотического индекса Вудивисса и индекса сапробности Пантле Букка., The results of the investigation of the species composition of the zoobenthos of some lakes of the Vishtynets group are presented. The ecological state of the lakes was assessed using individual saprobity indices of benthic organisms, the Woodivis biotic index and the Pantle-Bucc saprobity index.

Летом 2015-2016 гг. исследованы термическая структура и кислородный режим 11-ти водохранилищ Волго-Камского каскада. Проанализированы изменения состава и структуры зоопланктона и зообентоса в условиях дефицита растворенного кислорода. Установлено, что прогрев поверхности воды чаще всего превышал норму на 1.5-6°С, во всех водохранилищах особенно сильно вода прогревалась летом 2016 г. Кислородный режим в июне был благоприятным для гидробионтов по всей Волге, в августе на Средней и Нижней Волге, а также в Каме ниже плотины Воткинской ГЭС. Опасно низкое для животных содержание О2 (200 км русла Волги и Камы были заморными. Гибель беспозвоночных и рыбы в Камских водохранилищах регистрировали визуально во время экспедиционных работ. Многолетние (с 2011 г.) наблюдения на водоемах Верхней Волги указывают на увеличение частоты встреч летнего (июль-август) придонного дефицита кислорода, периода его проявления и мощности слоя над дном с недостатком кислорода. Выявлено, что формированию дефицита кислорода способствует повышенный прогрев (>20°С) глубоких слоев воды. В условиях недостатка кислорода снижается видовое богатство и обилие донных и планктонных ракообразных (Cladocera, Calanoida, Amphipoda), нарушается процесс размножения и уменьшается численность двустворчатых моллюсков сем. Dreissenidae, изменяется вертикальное распределение зоопланктона, уменьшается доля фильтраторов в планктоне и бентосе. Фильтраторы зоопланктона исчезают из состава доминантов при мощности слоя с О2, In summer 2015-2016, the thermal structure and oxygen regime were studied in 11 reservoirs of the VolgaKama cascade. Changes in the composition and structure of zooplankton and zoobenthos have been analyzed under conditions of dissolved oxygen deficiency. It has been found that water heating more often exceeded the norm by 1.5-6°С; in all reservoirs warming up of water was especially strong in summer 2016. In June, the oxygen regime was favorable for all hydrobionts over the entire Volga, and in August it was favorable in the Middle and Lower Volga and in the Kama River downstream the dam of the Votkinsk hydroelectric power station. Concentrations of oxygen (200 km in the Volga and Kama channels. Mortality of invertebrates and fish was registered visually during field surveys. Long-term (from 2011) studies in waterbodies of the Upper Volga indicate the increase in the frequency of summer (July-August) oxygen deficiency occurrence in the near-bottom layer, the period of its duration and the thickness of the above-bottom oxygen-deficient layer. It is found that strong water warming (>20°С) causes the formation of oxygen deficiency in deep water layers. The conditions of oxygen deficiency cause the decrease in the species richness and abundance of benthos and plankton crustaceans (Cladocera, Cal-anoida, Amphipoda), disruption of the reproduction process, decrease in the abundance of bivalve mollusks of the family Dreissenidae, changes in the vertical distribution of zooplankton, and decrease in the portion of filterers in plankton and benthos. Zooplankton filterers disappear from the composition of dominant species at the thickness of the layer with О2

Alterations to ecosystem function due to reductions in species richness are predicted to increase as humans continue to affect the marine environment, especially in coastal areas, which serve as the interface between land and sea. The potential functional consequences due to reductions in species diversity have attracted considerable attention recently but little is known about the consequence of such loss in natural communities. We examined how the potential for function is affected by natural reductions in taxon richness using empirical (non-simulated) coastal marine benthic macrofaunal data from the Skagerrak-Baltic Sea region (N. Europe), where taxon richness decreases 25-fold, from 151 to 6 taxa. To estimate functional changes we defined multiple traits (10 traits and 51 categories) on which trait category richness, functional diversity (FD) and number of taxa per trait category were calculated. Our results show that decrease in taxon richness leads to an overall reduction in function but functional richness remains comparatively high even at the lowest level of taxon richness. Although the taxonomic reduction was sharp, up to 96% of total taxon richness, we identified both potential thresholds in functioning and subtler changes where function was maintained along the gradient. The functional changes were not only caused by reductions in taxa per trait category, some categories were maintained or even increased. Primarily, the reduction in species richness altered trait categories related to feeding, living and movement and thus potentially could have an effect on various ecosystem processes. This highlights the importance of recognising ecosystem multifunctionality, especially at low taxonomic richness. We also found that in this system rare species (singletons) did not stand for the functional complexities and changes. Our findings were consistent with theoretical and experimental predictions and suggest that a large proportion of the information about alterations of function is found in measures such as functional diversity and number of taxa per trait category.

В работе обосновывается выделение особого направления гидробиологии гидробиология болот, как науки о биологических процессах в разнотипных водных объектах болот и их связи со средой. Основной целью гидробиологии болот признается изучение закономерностей формирования биологического разнообразия, структурно-функциональной организации, сезонной, межгодовой и многолетней динамики биоценозов болотных водоёмов и водотоков. В качестве объекта исследования выступают все живые организмы, обитающие в болотных водоёмах и водотоках, а предметом исследования является структура и экологическая роль сообществ гидробионтов в функционировании экосистем болотных водоёмов и водотоков. Постулируется, что тип болотного водного объекта (включая его происхождение, положение в пределах болотного массива, морфометрию) определяет структурно-функциональную организацию его экосистемы. Данные утверждения проверяются и иллюстрируются авторскими данными, полученными в результате многолетних исследований Шиченгского болота (Вологодская область). Описываются особенности таксономического, экологического состава и структурно-функциональной организации гидробиоценозов разнотипных болотных водных объектов данного болота, включая такие подсистемы как растительность, бактерио-, фито-, зоопланктон, макрозообентос; роль сфагновых мхов как ключевого таксона, особенности ценогенеза различных компонентов гидробиоценозов болот., The paper outlines and substantiates mire hydrobiology, a special area in hydrobiology, devoted to biological processes in different-type water objects of mires and the ways they are related to their environment. The main aim of mire hydrobiology is to study the regularities determining biodiversity, structural-functional organization, as well as seasonal, interannual, and long-term dynamics of communities in mire water bodies and water courses. All living organisms inhabiting mire water bodies and water courses may be considered as the object of study. The main issue is the structure and ecological role of aquatic communities in the functioning of ecosystems in mire water bodies and water courses. It is stated that the type of mire water object (including its genesis, location within the mire massif, morphometric features) determines the structural-functional organization of its ecosystem. The statement is verified and illustrated by the author's original data obtained in long-term studies of the Shichengskoe mire (Vologda Region). The distinguishing features of taxonomic and ecological composition and structural-functional organization of aquatic communities in different-type water objects of mires are described and analyzed, including such subsystems as the vegetation, bacterioplankton, phytoplankton, zooplankton and macrozoobenthos. The role of sphagnum mosses as a key taxonomic group and the coenogenetic traits of various components of mire aquatic communities are considered.

Non-native species exert considerable pressure on aquatic ecosystems; accordingly, they are treated as biopollutants. The Vistula Lagoon, one of the largest brackish water bodies in the Baltic, has become a part of the central corridor for hydrobionts migrating in the direction of western Europe and species expanding in inshore waters. Ten non-indigenous species of benthic invertebrates from five different biogeographical regions have been found in the western part of the Lagoon. Their considerable abundance relative to the numbers and abundance of native species testifies to the high level of biopollution there. The integrated biological contamination index (IBC) calculated for the macrobenthos in the western Vistula Lagoon was 4 and corresponds to the Lagoon’s poor ecological status.

Зоогеографический анализ видового состава макробеспозвоночных изученных в 1996-2011 гг. озерных систем юга Обь-Иртышского междуречья показал, что преобладают широко распространенные в Палеарктике и в западной части Палеарктики виды, а также виды, распространенные в Голарктике. Всего фауна водных макробеспозвоночных включает 11 типов распространения. Данные по зоогеографии изученных нами озер указывают на их принадлежность к западной части Палеарктики, что согласуется с известными системами зоогеографического районирования. Сравнительный анализ фауны выявленных гомотопных и гетеротопных видов выявил, что самые обширные ареалы (всесветные, голарктически-ориентально-неотропические и голарктически-эфиопско-неотропические) встречаются только среди гомотопных первичноводных архаичных таксонов. При этом восточно-палеарктические виды выявлены только среди гетеротопных видов амфибиотических насекомых. Также эти экологические группы отличаются доминирующими зоогеографическими ареалами: для гомотопов это западно-палеарктические, а для гетеротопов транспалеарктические., Zoogeographical analysis of species composition of macroinvertebrates of lake systems of the southern Ob-Irtysh interfluve in the 1996-2011 period showed the majority of species widespread in the Palaearctic and Western Palaearctic, as well as the ones, widespread in the Holarctic. Total fauna of water macroinvertebrates includes 11 types of distribution. The zoogeographical data of lakes studied indicate their belonging to the Western part of the Palaearctic that agrees well with the known systems of zoogeographical zoning. Comparative analysis of fauna of identified homotopic and heterotopic species revealed that the most extensive areas (worldwide, Holarctic-Oriental-Neotropical and Holarctic-Ethiopian-Neotropical) are found only among homotopic protoaquatic archaic taxa. However, the East-Palaearctic species were found only among heterotopic species, i.e. amphibiotic insects. These ecological groups are distinct in dominant zoogeographical areas: West-Palearctic area is for homotopic species, while Transpalaearctic is for heterotopic ones.

This work analyzed the qualitative and quantitative characteristics of zoobenthos communities of coastal shallow zone at Cheboksary reservoir during the vegetation period of 2014. In this regard, three sampling stations were provided, differing by soil, biotic and abiotic environmental conditions. Each station consists of two sections of reservoir shallow coastal area, where the research was performed: directly in the water line area, as well as at various depths of shallow water. The species composition of macrozoobenthos, the number and biomass indicators, the leading groups and organism taxa were specified. 41 taxa of aquatic invertebrates were revealed, 17 of which (41.5% of the total amount) occurred in the water line area and in littoral zone. The observed taxa belong to Mollusca, Arthropoda, Plathelminthes, Annelida types. The greatest species diversity was observed among insects (mainly Diptera representatives), as well as among mollusks. The high amount and biomass indices were observed among gastropods and bivalves, the invasive species Lithoglyphus naticoides (Pfeiffer, 1828), Dreissena polymorpha (Pallas, 1771), which play an important role in the communities of zoobenthos of the Volga-Kama reservoir system. High biomass indices were observed among gastropods, especially Viviparus viviparus (L., 1758). The water edge zone with high levels of biomass had a large amount of pond snails Lymnaea auricularia (L., 1758) and L. stagnalis (L., 1758) and the shallow water zone had a large amount of Unio longirostris (Rossmaessler, 1836) bivalves.

International audience; The macrozoobenthos living around two offshore gas platforms, Barbara NW (pB) and Calipso (pC) located in the northwestern Adriatic Sea were investigated for three years after their construction to detect eventual effects due to the platforms. The sampling stations were spaced at increasing distance from the platforms up to 1000 m. Both multivariate and univariate analysis showed an initial defaunation (short-term effect) at pB and within a 120 m radius at pC. A general recovery in terms of abundance, species richness and diversity was observed for the benthic communities after one year. During the third monitoring year a mussel mound developed at both the platforms (longer-term effect) extending up to 30 m from pC, whereas similar soft-bottom communities were found at all the other distances. The geographical position play an important role in the "timing" of the above effects. Moreover, despite the different environmental features, a 3-year monitoring plan can be effective to evaluate the potential impact on benthic communities of offshore gas platforms in the north-central Adriatic Sea.

The cohesive strength of intertidal soft sediments depends on a large range of physicochemical parameters, but the production of exopolymers by the inhabiting organisms is increasingly recognized as a major stabilizing factor. It is likely that the vast majority of these polymers are produced by microorganisms but very few studies have addressed the impact of benthic meiofauna on this microbial production. The major aim of this study was thus to estimate the impact of nematodes (often the main contributor to meiofauna abundance and biomass in temperate intertidal habitats) on the EPS (extracellular polymeric substances) production of marine sediments. Bacterivorous nematodes Diplolaimelloides meyli Timm, 1961 and D. oschei Meyl, 1954, bacteria and diatoms were grown in laboratory experiments both separately and together to estimate their respective influence. Our experiment revealed a positive impact of bacterivorous nematodes on microbial density and EPS production. Surprisingly, the biofilm structure (in terms of microbial abundance/biomass and EPS content) was better explained by the complexity (i.e. the number of trophic levels) of the assemblages rather than by any specific types of organisms involved in the experiment.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:43:37Z No. of bitstreams: 1 S1679-62252009000400020.pdf: 200941 bytes, checksum: 7f9d08fda5a7f1dc27351bfe976f41c3 (MD5) Made available in DSpace on 2013-08-22T18:43:37Z (GMT). No. of bitstreams: 1 S1679-62252009000400020.pdf: 200941 bytes, checksum: 7f9d08fda5a7f1dc27351bfe976f41c3 (MD5) Previous issue date: 2009-01-01 Made available in DSpace on 2013-09-30T18:39:49Z (GMT). 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No. of bitstreams: 2 S1679-62252009000400020.pdf: 200941 bytes, checksum: 7f9d08fda5a7f1dc27351bfe976f41c3 (MD5) S1679-62252009000400020.pdf.txt: 42413 bytes, checksum: afae0fec74f21eb76a1a8a622504e8d7 (MD5) Previous issue date: 2009-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Brazilian Nature Conservancy (TNC) Neste estudo foi avaliada a dieta das espécies de peixes do reservatório de Nova Avanhandava, baixo rio Tietê, Estado de São Paulo, Brasil. Os peixes foram coletados em dois trechos do reservatório: trecho Santa Bárbara (14 coletas) e trecho Bonito (duas coletas) entre setembro de 2002 e março de 2004, utilizando-se de redes de espera e arrasto. Os resultados das análisesde conteúdo estomacal foram expressos em frequência de ocorrência e método gravimétrico, combinados no Índice Alimentar (IAi). As 20 espécies analisadas consumiram um total de 52 itens, agrupados em 10 categorias alimentares: insetos aquáticos, insetos terrestres, crustáceos, peixes, macroinvertebrados, microcrustáceos, algas, material vegetal, detrito/sedimento e escamas. Os insetos aquáticos (principalmente Chironomidae, Odonata e Ephemeroptera) foram o recurso alimentar mais comum na dieta, consumido por 18 espécies. A análise da dieta da comunidade (espécies agrupadas) revelou que a categoria alimentar dominante foi insetos aquáticos (IAi = 77.6%), seguida pelos crustáceos (IAi = 7.1%). Quatro guildas tróficas foram identificadas pela análise de agrupamento (distância de Pearson): insetívoros (10 espécies), onívoros (4 espécies), detritívoros (3 espécies) e piscívoros/carcinófagos (3 espécies). Além do maior número de espécies, os insetívoros também foram responsáveis por mais de 80% das capturas em número de exemplares e biomassa (CPUEn e CPUEb). Os baixos valores de amplitude de nicho trófico apresentados por todas as espécies, juntamente com os baixos valores de sobreposição alimentar demonstram uma ampla partilha de recursos alimentares entre as espécies. Apesar de ser o principal recurso alimentar dos peixes insetívoros, os insetos aquáticos também foram um recurso complementar na dieta de outras espécies, o que demonstra a importância destes para a comunidade de peixes, sustentando uma alta diversidade, abundância e biomassa de peixes neste reservatório We evaluated the feeding of fish species of the Nova Avanhandava Reservoir, low Tietê River, São Paulo State, Brazil. Fishes were collected in two stretches of the reservoir: Santa Bárbara (14 samples) and Bonito (two samples) between September 2002 and March 2004, using gill and seining nets. The results of stomach contents analysis were expressed with the frequency of occurrence and gravimetric method, combined in the Alimentary Index (AI). The 20 species studied consumed 52 food items, grouped in 10 food categories: aquatic insects, terrestrial insects, crustaceans, fish, macroinvertebrates, microcrustaceans, algae, vegetal matter, detritus/sediment and scales. The aquatic insects (mainly Chironomidae, Odonata and Ephemeroptera) were the most common food resources, consumed by 18 species. The diet composition of the community (species grouped) indicated that the dominant food category in the diet of fishes was aquatic insects (AI = 77.6%), followed by crustaceans (AI = 7.1%). Four trophic guilds were identified according a cluster analysis (Pearson distance): insectivorous (10 species), omnivorous (4 species), detritivorous (3 species) and piscivorous/carcinophagous (3 species). Despite the highest number of species, the insectivorous guild was responsible for more than 80% in captures in number and biomass (CPUEn and CPUEb). The low values of niche breadth presented by all species, along with the low values of diet overlap between species pairs indicate a high degree of food resources partitioning among species. The aquatic insects, despite being the main food resource of insectivorous fishes, also complemented the diet of other species, which demonstrate the importance of this food resource for the fish community, sustaining a high diversity, abundance and biomass of fishes. Universidade Estadual Paulista Instituto de Biociências de Botucatu Departamento de Morfologia Universidade Estadual Paulista Instituto de Biociências de Botucatu Departamento de Morfologia FAPESP: 02/11113-6

In this study, the composition, specific richness and abundance of benthic macroinvertebrates (

The objectives of the present study were to describe the species composition, diversity and distribution of the zoobenthic assemblages, to estimate the abundance and biomass of the dominant species, and to identify the main environmental factors determining the distribution patterns of the invertebrates from a freshwater to an estuarine zone in a temperate estuary of South America. The Río de la Plata estuary is a microtidal system characterized by a high concentration of suspended solids. Fifty-three taxa of meso- and macro-invertebrates were identified in the samples collected during November and December 2001. Molluscs, annelids, crustaceans and nematodes were found at 90% of the sampling sites. Molluscs comprised up to about 90% of the total zoobenthos biomass: the remaining percentage corresponded mainly to annelids and less to nematodes and crustaceans. An ecocline along the salinity gradient could be observed for the benthic assemblages from the freshwater to the estuarine zone in Rio de la Plata. A Canonical Correspondence Analysis shows that results from sampling sites in the outer zone were strongly related to salinity, depth and pH and less to oxygen and percentage of clay. The results from stations in the inner zone, and part of the middle zone, were mainly related to the occurrence of sand and contents of NH4+–N, NO3−–N, and PO43−–P. Fil: Cortelezzi, Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología ; Argentina Fil: Rodrigues Capitulo, Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología ; Argentina Fil: Boccardi, Lucía. Universidad de la República. Facultad de Ciencias; Uruguay Fil: Arocena, Rafael. Universidad de la República. Facultad de Ciencias; Uruguay

Annually in Russia there not less than 3,5 billions tones of wastes are produced, from which only a quarter is processed, the rest is burned or removed to special landfills. Most of landfills is situated directly nearby built-up and natural areas. The objective of investigation in this work is revelation of parameters for impact assessment of Samosyrovsk landfill in Kazan on water bodies on the example of the river Krutovka. The main tasks of investigation are: gathering and analyzing data about Samosyrovsk landfill in Kazan; hydrochemical analysis of water samples of the river Krutovka and waste waters of the Samosyrovsk landfill on chemical elements content in it; hydrobiological investigation of the river Krutovka; separation of the most important parameters for further monitoring. Analyses were made on the basis of the international laboratory of the urban explorations of the Institute of social investigations on modernization of society and department of nature development and water use of KFU. It has been analyzed the existing monitoring system of landfills. The ecological state of the river Krutovka on hydrochemical and hydrobiological parameters has been assessed. It has been revealed chloride, copper, magnesium, calcium pollution of the stream. It has been shown parameters of zoobenthos allowing to more precisely assess the state of the water body. Such indicators are: aspectual content, ratio of quantity and biomasses of the basic groups of organisms, calculation of Shannon and Simpson indices, account of presence chironomidae organisms in assays.

Zusammenfassung: Die Studie befasst sich mit den biologischen Verànderungen an Karstquellen im alpinen Raum, hervorgerufen durch langzeitigen Einfluss aus Aimund Forstwirtschaft. Die Auswirkungen werden anhand der aquatischen Fauna und der Habi- tatausstattung der Quellbereiche dokumen- tiert. Die Ergebnisse zeichnen das deutliche Bild einer weitreichenden Veránderung und Verarmung der Quellhabitate bei starker Re- duktion der gewàssertypischen Biozônose. Wàhrend sich die Lebensgemeinschaft eines unbeeintráchtigten Quellaustrittes zu mehr als 70 % aus typischen Faunenelementen der Quellregion zusammensetzt, ist diese Fauna in Quellen die bereits seit vielen Jahrzehnten in einer gerodeten Almweide liegen nahezu vôllig erloschen (der Anteil an der Gesamt- zoozonose betrágt nur mehr etwa 5 %). Stark verándert ist die Besiedlung auch jener Quellen, die inmitten eines Fichtenforstes liegen (der Anteil liegt bei rund 25 %) oder sich seit wenigen Jahren in einem forstlichen Kahl- schlag befinden (rund 15 %). An die Stelle der naturgemàfien Biozónose treten vor allem Arten mit geringeren Lebensraumanspriichen (Ubiquisten) und weiter geographischer Verbreitung (Kosmopoliten). Es handelt sich hierbei vorwiegend um Faunenelemente der Gebirgsbàche und um Schlammbewohner sommerwarmer Stillgewàsser. Eine naturbe- lassene Biozönose von Waldquellen steht in elementarer Beziehung mit der umgebenden terrestrischen Vegetation (ausgeglichenes Lichtklima, Wassertemperatur, Wachstum der Quellmoose, Eintrag von Falllaub und Totholz u.a.)., The study deals with the ecological consequences on springs in alpine regions, caused by long-term influences of cattle breeding and forestry, respectively deforestation. Biotopes and community patterns of macrozoobenthos were observed to find out about biotic reactions to environmental changes. The results show an enormous shift in habitat composition as well as a dramatic reduction of habitat specific invertebrate species. Inaffected springs show community patterns with more than 70% of typical cre- nal invertebrate species, whereas springs that are situated in spruce forests show just 25%, those in deforestated areas only 15 %, and springs in alpine pastures are those with the smallest share of crenal invertebrates with an amount of only 5 %. Instead of species that are adapted to clear, cold water with high concentrations of oxygen, we find more and more cosmopolitans or differently adapted invertebrates in affected sources, such as species that normally can be found in upper course of streams or even in ponds. A natural forest stand is extremely important to a source and its inhabitants, providing it with nutrients and microhabitats such as fallen leaves or branches, and finally creating an equilibrium of light and shadow., Résumé : Evaluation hydro-écologique des effets du pastoralisme et de la sylviculture sur les sources karstiques dans le Parc national des Kalkalpen (Autriche). Cette étude analyse les changements biologiques des sources karstiques dans l'espace alpin occasionnés par le pastoralisme et la sylviculture. La faune aquatique ainsi que les habitats des sources sont des indicateurs de ces effets. Les résultats sont significatifs : un vaste changement et l'appauvrissement des habitats accompagnent la réduction des biocénoses aquatiques types. Les biocénoses d'une émergence naturelle sont normalement composées de plus de 70 % d'éléments faunistiques typiques des sources. La faune des sources subissant depuis des décennies les effets d'un pacage sur des zones défrichées a presque disparu (le pourcentage de la zoocénose n'est plus que de 5 %). Le peuplement de ces sources se situant dans des forêts d'épicéa (pourcentage aux alentours de 25 %) ou bien se trouvant sur des surfaces où des coupes à blanc ont été pratiquées (environ 15%) s'est largement modifié. A la place des biocénoses naturelles se développent des espèces peu exigeantes (Ubiquistes) et de répartition géographique large (Cosmopolites). Il s'agit principalement d'une faune peuplant les torrents, les dépôts limoneux des eaux stagnantes chaudes. Une biocénose naturelle de sources forestières est en relation étroite avec la végétation terrestre voisine (lumières équilibrées, température de l'eau, croissance des mousses des sources, feuilles mortes et bois mort et al)., Weigand Erich, Pelikan Ulrich, Ratschan Clemens, Scheder Christian. Gewässerökologische Bewertung des Einflusses von Alm- und Forstwirtschaft auf Karstquellen im Nationalpark Kalkalpen (Osterreich) / Evaluation hydro-écologique des effets du pastoralisme et de la sylviculture sur les sources karstiques dans le Parc national des Kalkalpen (Autriche). In: Revue de géographie alpine, tome 90, n°2, 2002. pp. 103-115.

© 2014, Pleiades Publishing, Ltd. An assessment of the ecological state of the small Shava River (Kstovskii raion, Nizhnii Novgorod oblast) subjected to oil pollution as a result of a pipeline accident in 2007 is presented. On the basis of physical and chemical characteristics of water quality and the results of a study of hydrobiont communities, the degree of the river pollution has been determined and a conclusion about the rehabilitation of communities as a result of the complex effect of recultivation measures and self-purification processes has been made. Criteria for recultivation activity completion have been defined according to hydrobiological indicators (phytoplankton, zooplankton, and zoobenthos).

Охарактеризован видовой состав, а также уровень развития макрозообентоса водохранилища на р. Черновой Уроп. Выявлены доминирующие таксоны донных беспозвоночных. Дана оценка качества воды водохранилища методами биоиндикации по составу и структуре макрозообентоса., The species composition and the development of macrozoobenthos in reservoir on Chernovoy Urop river are characterized. The dominant taxa of benthic invertebrates are identified. The estimation of reservoir water quality using the bioindication methods on macrozoobenthos composition and structure.

Gammaridean amphipods appear ubiquitous in the shelf communities of the eastern Weddell Sea where more than 230 species have been recorded. Comparison of catches of the 40 most common species taken by different gears and ethological observations in the aquarium allowed us to distinguish 6 groups: endobenthic, epibenthic, hyperbenthic (or suprabenthic), benthopelagic, pelagic and cryopelagic. Only epibenthic species, which form the bulk of the fauna, are dealtwith in the present paper. Aquarium observations indicated three different epibenthic strata occupied by amphipods: the sediment surface, and a lower and upper level on the substrata formed by sessile suspension feeders. In addition, four symbiotic microhabitats were detected in or on sponges, ascidians, hydrozoans and gorgonians.