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In order to build an evaluation criteria and standard of river ecosystem health for the sustainable development, the Benthic-Index of Biotic Integrity was applied to evaluate the health state of Xiaoqing River. From May 2014 to October 2015, 32 candidate metrics were selected from 58 zoobenthos investigated for 6 times from 7 typical sampling sites in Xiaoqing River. Then, after distribution range, discriminant ability and correlation analysis, five key metrics were detected and entered into the final B-IBI system. The B-IBI standard for health assessment of Xiaoqing River established by ratio method was that ＞3.70 represented excellent, （2.77, 3.70] represented good, (1.85, 2.77] represented fair, (0.92,1.85] represented poor and ≤0.92 represented very poor. The results show that Wujiabao sampling point is in the state of “health”, Wuliu Gate and Shicun Village sampling points are in the state of “subhealth”, Huangtai Bridge and Wulongtang sampling points are in the state of “general”, Liangfuzhuang and Chahe Hydrological Station sampling points are in the state of “poor”. The BIBI value is negatively correlated with total nitrogen and total phosphorus and positively correlated with Shannon Wiener diversity index. In summary, the evaluation criteria and standard of B-IBI have better applicability on Xiaoqing River’s health. [ABSTRACT FROM AUTHOR]

Free-living marine nematodes were employed in ecological studies and were proven to be suitable bioindicators of pollution-induced effects on the benthic domain. This study represents the first attempt to use nematode descriptors in order to assign ecological quality (EcoQ) status to areas along the Sarawak coasts, thus integrating the methods actually applied by the Department of Environment (DOE). Three nematode parameters, i.e. colonizer–persister percentage, maturity index (MI), and Shannon diversity index (Hˈ), were used, as they are recognized as the best descriptors of EcoQ status in coastal habitats. The thresholds applied to the nematode parameters for the Sarawak study sites showed predominantly moderate and bad EcoQ status, with the exception of the Similajau site, which being close to a national park was found to have good EcoQ. The sites with the worst EcoQ were characterized by low salinity values, suggesting riverine inflows as a primary source of pollution, likely from the discharge of untreated wastes. This was confirmed by both the Hˈ and MI indices, which showed a close positive relation with salinity. Results obtained for the Niah site may suggest that “traces” of pollution were left in the nematode assemblages that could not be detected from other parameters of the water column. This investigation shows that analysis of nematode descriptors could be effectively applied to ecological assessment criteria within environmental policies of rapid growth countries such as Malaysia. Furthermore, it certainly suggests the need for management and conservation actions in the Sarawak coasts aimed at more sustainable use of the marine resources to prevent the loss of biodiversity. [ABSTRACT FROM AUTHOR]

The study was performed in five fourth-order tributaries of the Bystrzyca Lubelska River (Eastern Poland, Lublin Upland), differing in the degree of river-bed transformation and level of pollution. Hydro-morphological methods (descriptive method by Ilnicki and Lewandowski - IL, and index method by Oglecki and Pawlat - OP) and biological indices based on the composition of zoobenthos (Diversity - D, and index based on proportions between the density of Oligochaeta and Chironomidae - O/Ch) permitted distinguishing of four classes, from II to V. The distinguishing of only two quality classes (III and IV) was possible by means of physical-chemical methods and by benthic index BMWP_PL. Those two methods seem to show the lowest sensitivity to the spatial variability of the environment quality. The BMWP_PL index was the least sensitive to year-to-year environmental changes, and O/Ch was the most sensitive. Relatively high conformity was obtained between hydro-morphological assessments performed by means of the OP and IL methods. Results obtained by means of these tools weakly corresponded with the physical-chemical assessments. The latter assessments were the most similar to those obtained by means of the BMWP_PL (degree of similarity = 57%) and D (47%) indices, and considerably less in the case of O/Ch (36%). The BMWP_PL and D indices better corresponded with the results of the hydro-morphological assessment performed by means of the IL method than with those performed by means of the OP method while D index showed a reverse pattern. The O/CH index proved useful for the assessment of the degree of organic pollution of the river's water, but not the sediments. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The biomass and the qualitative parameters of zoobenthos¹ of Lake Sevan (Armenia) were observed during the different strategies of water level management (1928-2016) where after 20 m water level drop (1933-2001) the water level increased on about 4 m (2002-2017). During this period the annual wet biomass varied between 3 and 37 G M-2. Changes in feeding structure of the benthic community: ratio between first level consumers: detritivores, herbivores and filter feeders, and between first and second (predators) levels consumers are less visible but sign about important qualitative changes followed by quantitative ones. This facilitates prediction of the abundance of the zoobenthos and its structure in future years. Further, changes in relative proportions of the zoobenthos comprised by feeding groups provide clear indices of progress toward rehabilitation of the lake. [ABSTRACT FROM AUTHOR]

We achieved a long term (i.e., 1998 vs. 2010) large scale (i.e., whole Gulf of Lions) study of benthic macrofauna composition in the Gulf of Lions based on the resampling of 91 stations located along 21 inshore-offshore transects. Results show that the 3 main benthic communities identified in 1998 were still present in 2010 although their composition changed. Using only year and station of sampling we found a significant space-time interaction explaining changes in macrofaunal community composition, and, in this study, stations differ primarily in terms of depth and distance to the Rhône river mouth. Temporal changes in benthic macrofauna composition were clearly most important at shallow stations (i.e., in the Littoral Fine Sand community) than at deep ones (i.e., Terrigenous Coastal Mud community). These results are in good agreement with the current paradigm according to which climatic oscillations such as NAO (North Atlantic Oscillation) and WeMO (Western Mediterranean Oscillation) are indirectly (i.e., through changes in the frequency of occurrence and the intensity of storms) controlling benthic macrofauna composition in the Gulf of Lions. This hypothesis is further supported by a meta-analysis of changes in the average and maximal yearly abundances of the polychaete Ditrupa arietina . At last, the spatial modelling of 1998 and 2010 benthic macrofauna compositions both suggested a significant effect of Rhône River inputs on the spatial distribution of benthic macrofauna in the Gulf of Lions. [ABSTRACT FROM AUTHOR]

The effect of anthropogenic pollution on the structure of benthic animal communities in the Barnaulka R. (Ob tributary) has been studied. Statistical analysis was used to assess the effect of habitat factors on macrozoobenthos structure. The structure characteristics of benthic macroinvertebrate communities and the bioindication indices calculated from them are shown to depend on the hydrophysical and hydrochemical characteristics of water and bottom sediments. [ABSTRACT FROM AUTHOR]

Chironomid larvae are common members of benthic systems in freshwaters. Their diet consists mainly of detritus, which often leads to the passive ingestion of attached organisms. We hypothesized that larvae would have a strong trophic effect on protozoans and meiofauna. We investigated experimentally the direct effect of 2 densities (1 and 4 larvae/16 cm²) of Chironomus riparius, a nonselective macrofaunal deposit feeder, on a natural zoobenthic community. Larvae significantly reduced the abundance of total meiofauna (nematodes, rotifers, oligochaetes, and copepods) to 56 (1 larva) and 52% (4 larvae) of their initial abundance after 1 d. Protozoans were slightly reduced by 1 larva but their densities increased when 4 larvae were present. A strong decrease in copepod abundance led to a decrease in total meiofaunal biomass to 40 (1 larva) and 43% (4 larvae) of their initial biomass after 8 d. Organisms with body lengths between 0.125 and 1 mm were ingested preferentially. These results indicate that the presence and feeding behavior of chironomids can strongly shape meiobenthic communities and indirectly affect protozoans. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The production characteristics of zooplankton and zoobenthos communities have been studied in several lakes and reservoirs. Their relationship with the primary production of plankton and the biomass of the communities is shown. The P/B ratio in the zooplankton community is five times higher than the ratio in the benthic communities. The greatest number of stenobiont species in the zooplankton communities is recorded at a water transparency close to 4 m. [ABSTRACT FROM AUTHOR]

Abstract Brazilian floodplains have suffered great changes in their natural characteristics in recent decades, mainly in the flood pulse. The Upper Paraná River floodplain is one of the few places where are found remained areas in which such peculiar characteristics keep reflecting on its high biodiversity. Ephemeroptera nymphs are one of the higher density groups among benthic community, occurring in many water bodies like large rivers and secondary channels. We sought to understand which factors are needed for the species establishment and how much important is the species colonization, especially in environments with anthropogenic changes. The marginal areas, which are more structured with presence of macrophytes, showed the highest density and richness even in the Paraná River that has great human impact. We verified dominance of Americabaetis alphus, Tricorythopsis araponga, Tricorythopsis artigas on the Parana River, correlated with transparency, depth and electric conductivity, while the dominance of Traverella sp. was correlated with water temperature, especially in marginal areas. Consequently, the increasing transparency and electric conductivity due to the Porto Primavera dam in Parana River can be favoring those Ephemeroptera species. We demonstrated the importance of preserving the wetlands of Ivinhema River State Park mainly for Guajirolus sp., which was only registered in this region. Therefore, our study provides support for understanding gaps from previously studies using artificial substrates in three large rivers which are of great importance to the upper Paraná River floodplain.

Aim. The assessment of the ecological status of watercourses of Delta of the Volga River on the structure of benthic communities. The main objective of our researches was the assess the ecological status of watercourses of Delta of the Volga River on the basis of the analyzes of the structural-functional characteristics of benthic communities.Location. Delta of the Volga River was the area of researches.Methods. Processing samples of zoobenthos of the studied watercourses of Delta of the Volga River was produced according to standard techniques. (Zhadan V.I.,1960, Vinberg G.G., 1984, Abakumov V.A., 1992). Altogether were selected and processed 516 samples of zoobenthos. Species identification was done using the "Atlas of invertebrates of the Caspian Sea" (Birshtein A.Ya., 1968)and “The determinant to freshwater invertebrates…” (Kutikova L.A., 1977). Next, based on the obtained data, we determined the abundance and biomass of species per m2 surface area of the bottom. To the assessment of the ecological status of watercourses of Delta of the Volga River by the structure of microzoobenthos we used the following indicators: number of species, abundance (N, specimens/m2), biomass (B, g/m2), percentage of principal taxonomic groups, oligogenic index of Parele (D1) (Parele E. A., 1974), biotic index of Wudiwiss in the modification of Nasibulina (B) (Nasibulina B. M., 1995), the index of species diversity of Shannon-Uiver (H, bit/copy) (Shitikov V. K., 2003).Results. The obtained results of the assessment of the ecological status of watercourses in the Delta of the Volga River by the structure of benthic communities show that the same species having in different water bodies their different representation and structural-functional characteristics were the kernel of bottom fauna. According to the values of the modified biotic index of Wudiwiss and oligochaetae index of Parele calculated for the whole period of studies, the water quality in the Volga River (from Barbasi to water-post, Astrakhan), and the sleeves Buzan and Akhtuba was characterized as "slightly contaminated"with the dominance of β-mesosaprobic organisms. n the sleeveless Bushma, Kizan', Bakhtemir characterised as "polluted" with a predominance of β-α-mesosaprobic. The picture of the distribution of quantitative indicators of zoobenthos in the Delta of the Volga River in average perennial aspect had uneven character, with the manifestation of a clear trend to decreasing their values from the Eastern part of the Delta (the Volga River) to the West (the sleeve Bakhtemir).Main conclusions. Thereby, on the basis of qualitative and quantitative characteristics of zoobenthos and calculated biological indices it was noted that the water quality of watercourses in the Delta of the Volga River can be characterized as "Slightly contaminated and "Polluted". In the average perennial aspect in the watercourses of Delta of the Volga River was observed uneven distribution of quantitative indicators of zoobenthos with the manifestation of a clear trend to decreasing their values from the Eastern part of the Delta to the West.

Abstract. Aim. Industrialization of Caspian oil and gas supplies requires a serious approach to the problem of protecting and preserving the region’s unique environment that, in fact, represents a property of international commons. The article studies into the impact of the Caspian modified waters on the benthos faunistic composition.Methods. Zooplancton and zoobenthos hydrobiology material was collected in the Central Caspian survey loop. Samples were collected in spring and summer in 2002 – 2007 in the western part of the Caspian Sea (Dagestan offshore location of the Caspian Sea from Smirnovsky Midstream Sandbank and Pearl Bank till Derbent latitude) on “Tsada” vessel. They were collected from 25 stations located on ten standard parallel latitude logs with depth scope of 8–100 m from 0, 10, 25, 100 m horizons. These samples were used as a material for characterizing phyto- and zooplankton.Results. The benthic can be considered the most stable communities of the marine environment as they are the most resilient to quantity and modifications. Heterogeneous and variable ecosystem (biotope) is typical of the areas with strong currents as the organic quality, quantity and physic-chemical properties are marked by variability.Location. The Caspian zoobenthos state as well as the features of the Caspian Sea benthos communities characterize the ecology of the Caspian Sea and give a true view of the situation in the drilling sites. This will help predict and avert negative effect of hydrocarbon production on the Caspian Sea ecosystem. Main conclusions. Water modification must be intensive, long-lasting and frequent for it to have an impact on benthos.

Kharbeyskie Lakes situated on the North-East of the European Russia were sampled. The aim of the present work was to evaluate the changes in the lakes ecosystems which took place during more than 40 years since the first sampling in 1960’s. Faunal richness of aquatic communities changed insignificantly under warming climate and low anthropogenic impacts. Nevertheless, the following changes in zooplankton community of the lakes can be considered as the signs of their oligotrophication: the abundance of species indicating oligotrophic water has increased, the abundance of species indicating eutrophy has decreased, the crustacean role comparing the role of rotifers in zooplankton in quantitative terms has grown, faunal coefficients of trophy (E, E/O) have reduced. According to the structural characteristics of zooplankton the large Kharbeyskie lakes are oligotrophic at present. Zoobenthos is more inert community than zooplankton under influence of environmental changes. According to the data on zoobenthic abundance, biomass, composition and structure, the Kharbeyskie Lakes are mesotrophic ecosystems as well as they were in 1968 and 1969. Some dynamic features of the studied aquatic communities indicate a warming influence on the ecosystem of the Kharbeyskie Lakes in the 2000s. These include increasing of abundance and biomass of zooplankton, zoobenthos and some plankton and benthos taxa and the appearance of thermophilic and eutrofication indicating species in zooplankton

Purpose. Investigation of the effect of higher aquatic vegetation growing on shallow water areas of the Kyiv reservoir on conditions of spawning of commercial fish species and growth of their juveniles. Methodology. Materials for the study were higher aquatic plants, the number of which was counted with the aid of a 1 x 1 m frame. Bottom deposits for determination of the biomass of benthic organisms were collected using dredges of different constructions. Fish juveniles were caught using beach seine. Dissolved oxygen content was measured with the aid of the thermooximeter AZhA-101M. Findings. It was found that during last years, shallow water areas of the Kyiv reservoirs are characterized by rapid colonization with higher aquatic vegetation. The most abundant among them is water chestnut, the number of which reaches 75 %. Its number on some areas of the upper part of the reservoir reaches 75 plants per 1 m2. During summer, with water temperature of 25 – 27 0С, a reduction of dissolved oxygen content to 0,5 – 0,7 mg/L was observed that resulted to fish kills. A dependence of the number of benthic organisms from vegetation type, which grows on these areas, was found. It was found that fish juveniles are absent on areas, where water chestnut predominated. Originality. Every year, areas covered by water chestnut considerably expand that result in deterioration of hydrological regime of the reservoir. Significant siltation of bays due to slowdown of water current is observed. Reduction of oxygen content in water leads to decrease of both benthic organisms and fish juveniles. Practical Value. It is recommended to conduct a complex enhancement of shallow water areas of the Kiev reservoir but due to the fact that water chestnut is listed in the Red Book of Ukraine as a protected species, it is prohibited to conduct such enhancement works aimed at reducing areas covered by this species.

This research work was carried out to determine the effects of water contamination on the fatty acid (FA) profile of periphyton, zoobenthos, two Chinese carps and a common carp (Hypophthalmichthys molitrix, Ctenopharygodon idella and Cyprinus carpio), captured from highly polluted (HP), less polluted (LP), and non-polluted (NP) sites of the Indus river. We found that the concentration of heavy metals in the river water from the polluted locations exceeded the permissible limits suggested by the World Health Organization (WHO) and the US Environmental Protection Agency (EPA). Fatty acid profiles in periphyton, zoobenthos, H. molitrix, C. idella, and C. carpio in the food web of river ecosystems with different pollution levels were assessed. Lauric acid and arachidic acids were not detected in the biomass of periphyton and zoobenthos from HP and LP sites compared to NP sites. Alpha-linolenic acid (ALA), eicosadienoic acid and docosapentaenoic acid were not recorded in the biomass samples of periphyton and zoobenthos in both HP and LP sites. Caprylic acid, lauric acid, and arachidic acid were not found in H. molitrix, C. idella, and C. carpio captured from HP. In this study, 6 and 9 omega series FAs were identified in the muscle samples of H. molitrix, C. idella and C. carpio captured from HP and LP sites compared to NP sites, respectively. Less polyunsaturated fatty acids were observed in the muscle samples of H. molitrix, C. idella, and C. carpio collected from HP than from LP. The heavy metals showed significant negative correlations with the total FAs in periphyton, zoobenthos, and fish samples.

Purpose. To investigate the effect of brewer᾽s grains on formation of hydrochemical regime, development of natural forage base, and fish productivity in nursery ponds. Methodology. Generally accepted methods for hydrochemistry, hydrobiology and fish farming have been used. For general (full) chemical analysis, water samples were taken 2 times a season (at the beginning and end of the growing season), a short chemical analysis of water was conducted twice a month. Hydrobiological samples (phytoplankton, zooplankton, zoobenthos) were collected before and after the application of organic fertilizers and throughout the growing season 2-3 times a month. Findings. The article summarizes the results of studies conducted during 2007-2009 devoted to the use of different doses and schemes of application of brewer’s grains in nursery ponds. Effects of brewers’ grains of hydrochemical regime, development of natural food base (phyto-, zooplankton, zoobenthos) and fish productivity in nursery ponds have been studied. It was found that the brewer᾽s grains stimulates the development of natural forage base for juvenile fish and can be an alternative to traditional organic fertilizers ― humus. Adding of brewers’ grains (dry matter content of 29,4 %) to the nursery ponds at the rate of 2,0 t/ha (once or twice during the growing season) ensured the development of phytoplankton to 33,52 dm3, zooplankton ― up to 37,97 g/m3, benthos ― up to 3,43 g/m2. Fish productivity in nursery ponds production reached 736,3 – 754,6 kg/ha. Originality. Peculiarities of formation of hydrochemical regime and development of phyto-, zooplankton, and zoobenthos have been studied for the first time when using wastes of the brewery industry – brewer’s grains for fertilization of nursery ponds. It was found that brewer᾽s grains contribute to an increase of the development of natural forage base and fish productivity in ponds. Practical Value. Based on these results, it was proposed to put into practice the use of pond fish brewer᾽s grain, as non-traditional organic fertilizers, to stimulate the development of natural forage base nursery in ponds to enhance their fish productivity.

Spatial, seasonal, and inter-annual variation in zoobenthos was examined in Lake Winnipeg which has experienced accelerated nutrient loading and multiple environmental stressors over the last several decades leading to increased overall productivity. Qualitative zoobenthos data (1928–29) and quantitative data (1969–2013), revealed two prevailing patterns: (1) a substantial increase in density, mainly Oligochaeta (Tubificinae), Mollusca (Sphaeriidae), and Diptera (Chironomidae) in the North basin, but a less consistent pattern of increase in density overall and of Ephemeroptera (Ephemeridae) and Trichoptera (Leptoceridae) in the South basin, and (2) disappearance of Amphipoda ( Diporeia ) from the South basin and a decline in Diporeia as a dominant taxon in the North basin, although it remained prevalent in the Narrows where higher total organic carbon (TOC) concentrations have persisted. Permutational analysis of variance (PERMANOVA) revealed that over time, inter-basin variation overwhelmed the seasonal component of variation in zoobenthos abundance. The benthic environment has changed (e.g. food resources, sediment particle sizes and nutrients) over the decades, contributing to the substantial changes in zoobenthos abundance and community composition that may constitute a regime change in the lake. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The Neva Estuary situated in the eastern part of the Gulf of Finland is one of the largest estuaries of the Baltic Sea. At present, heavy nutrient and organic matter loading, mainly from the Neva River and point sources in the upper estuary are the most serious environmental problem for the Neva Estuary and adjacent parts of the eastern Gulf of Finland. Long-term studies of mid-summer primary production and mineralization of organic matter were conducted in upper and middle parts of the Neva Estuary. A considerable increase of production and biomass of phytoplankton was observed in the middle part of the estuary during the last decades mainly due to an increase in biomass of cyanobacteria. However, they are mostly concentrated in the upper water layers and only a small part of them reached the near bottom water layers and may be used as a food by zoobenthos. The mineralization of organic matter in the water column was twice higher than primary production that indicates the importance of allochthonous organic matter in the carbon budget of the both parts of the estuary. The carbon isotope signature of seston and most of the zoobenthic species in the upper part of the estuary was close to the signature of allochthonous carbon leaking from watershed (− 27‰). Higher values of δ 13 C of seston in the upper mix layer of the Middle estuary indicate intensive primary production in mid-summer. The carbon isotopic signature of zoobenthos in this part of the estuary was also in general lower than in the Neva Bay reflected higher importance of autochthonous organic matter in food webs of the estuary. [ABSTRACT FROM AUTHOR]

On the example of Lake Sevan (Armenia), on the basis of long-term data, the predator (fish) - victim (zoobenthos and zooplankton) relationship was analyzed in conditions of changes in the trophic status of the large freshwater high-altitude water body. [ABSTRACT FROM AUTHOR]

In order to reveal the differentiated responses of plankton and zoobenthos to water quality on both annual and seasonal time scales, an ecological study on plankton and zoobenthos community was conducted during 2011 to 2015 in Nansi Lake in northern China. Different dynamics were found among phytoplankton, zooplankton, and zoobenthos in terms of density, biomass, and biodiversity. On an annual time scale and with deterioration of water quality, density and biomass of plankton and zoobenthos showed different variations, while phytoplankton (density, biomass, and biodiversity) changed significantly when water quality improved. On a seasonal time scale, density and biomass of phytoplankton showed significant differences between spring and summer. Results of Pearson's correlation analysis revealed that phytoplankton, zooplankton, and zoobenthos were significantly affected by different environmental factors. Our study demonstrated that phytoplankton was more sensitive to water quality changes than zooplankton and zoobenthos. These results suggest that density and biomass of phytoplankton could rapidly reflect water quality, whereas biodiversity of phytoplankton could indicate long-term status of water quality combined with the physico-chemical parameters of water. The results could contribute to predicting the dynamics of plankton and zoobenthos in freshwater lakes and to selecting effective bio-indicators for ecosystem health assessment of freshwater lakes. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM PUBLISHER]

The seasonal dynamics of feeding spectra and diet of Arctic graying in a stretch of the middle reaches of the Yenisei River (from the dam of the Krasnoyarsk HPP to the mouth of the Kan River) was studied in 2009-2013. Its connection with the food-supply state and fish growth has been traced. It has been shown that the intensity of fish feeding is relatively stable throughout the year, despite significant fluctuations in zoobenthos biomass. The contribution of groups dominating in diet (amphipods and larvae of caddisflies) changes depending on the month. Amphipods prevail in the diet of fish during the period from June to October and caddisflies prevail in the winter and spring months. Among caddisflies, selective feeding on a small species, Apatania crymophila, has been revealed. The change of the primary diet component during the summer period corresponds to a sharp increase in the coefficients of relative condition factors with a peak in August-September. It has been assumed that changes in the ratio of weight and linear sizes of fish are associated not only with an increase in the water temperature, but also with the grayling switching to the consumption of amphipods with a higher nutrition value. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study measured the elemental and species concentrations of arsenic (As) in the water, sediments and food webs of two shallow Chinese freshwater lakes. Organic As species were widely detected in various organisms from the two lakes (60%-100% of the total). Among these organisms, dimethylarsinic acid (DMA) was predominant in most of the samples. The average concentrations and corresponding proportions were 0.59 mg/kg, 81% in fish; 3.24 mg/kg, 70.63% in zoobenthos; and 1.34 mg/kg, 79% in plants. The average concentrations and corresponding proportions of monomethylarsonic acid (MMA) and inorganic As were much lower, ranging from n.d. (not detected) to 1.94 mg/kg and from n.d. to 1.54 mg/kg, with an average proportion of 14 and 7.4%, respectively. In Lake Taihu, the mean As concentrations in different fish tissues were generally low and in the following order: eggs (0.47) < skin (0.62) < muscles (0.91) < gills (1.65) < livers (5.47) mg/kg. DMA occupied 75%-100% of the total As species, while MMA and inorganic As were much less prevalent. [ABSTRACT FROM AUTHOR]

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Temporary water bodies, connected or not to permanent wetlands, have a major importance for the regional biodiversity, acting as source of individuals for recolonization, refuge habitats or foraging sites. Colonization of zoobenthos and zooplankton from Lake Sucutardul Mare into its temporary fry pond was investigated in summer and autumn 2015. The instability of the temporary water pool, which dried out in autumn, together with its lower habitat heterogeneity led to decreased numbers of zoobenthic colonizers, that failed to survive in this "sink" habitat. No true colonization occurred in case of zooplankton, since the permanent connection between the two ponds led to similar animal communities in the water column. A rapid shift between the dominant zooplankton groups, rotifers and copepods, was observed. [ABSTRACT FROM AUTHOR]

Multidisciplinary studies were carried out in the Lower Don River in the low-water November of 2012. The studies showed relatively low concentrations of oil products (up to 2 MAC) and heavy metals (up to 1 MAC), which were likely due to the cessation of navigation in the river. However, copper concentration was found to be in excess of its MAC. The most polluted were found to be the port water areas of the cities of Volgodonsk, Ust'-Donetsk, and Semikarakorsk. The distribution of nutrients over streams is uneven: the Don water is poorer in nutrients than the waters of the Severskii Donets and the Manych are. Oxbows can serve as depots of organic matter, where it accumulates over longer periods than in the river. The residual manifestations of the summer-autumn blooming of blue-green algae, observed in shallows, the predominance of algae of divisions Cryptophyta and Bacillariophyta (typical representatives of winter planktonic algacenosis), and their low abundance suggest the transitional state of phytoplankton communities to autumn-winter season (pre-winter period). The species diversity and biomass of zooplankton were largest in the Don R. and lowest in the Severskii Donets R. The formation of zooplankton species composition shows the effect of the runoff from the Tsimlyanskoe Reservoir. An increase in the proportion of oligochaetes and invading species was recorded in the Don. The decrease in the diversity of benthos is attributed to natural factors, i.e., the decay of imago and thicket forms in autumn. The biomass of the soft (food) benthos is low because of the predominance of its small-size forms. [ABSTRACT FROM AUTHOR]

Arctic hard-bottom locations are habitats for a variety of benthic organisms, which have been described by species occurrence, abundance, or biomass. However, only few studies have included descriptions of communities on such locations in the Arctic, whereas this has been frequently done for soft-bottom communities. Thus, the focus of this study is to determine a limited number of characteristic zoobenthic communities that occupy Arctic shallow subtidal habitats on hard-bottom locations in Kongsfjorden, Svalbard. The habitats at these locations graded from bedrock near the surface to mixed bottom with pockets of loose gravel and sediments deeper. Samples were collected by divers in August and September 1996 and 1998 from two square frames (0.25 m) from each of the depths 0-2.5-5-10-15-20-25-30 m at all transects except JUTT (max. 15 m) and OSSI (max. 5 m). Seven communities were identified after considering species dominance, similarity between species associations, and the potential role of conspicuous species in the communities. The communities were described as: 1-Amphipoda community; 2- Symplectoscyphus community; 3-Branched bryozoans community; 4-'Developed fauna' community; 5-'Impoverished fauna' community; 6- Balanus community; and 7-Bivalvia community. Segregation of communities was based on species dominance (biomass), as confirmed by multivariate analyses. Species primarily responsible for the establishment of communities were determined, and particularly the importance of barnacles ( Balanus balanus) and Branched bryozoans ( Eucratea loricata and Tricellaria ternata) is discussed. Macroalgae were of less importance for identification of communities and distributional patterns of zoobenthos. [ABSTRACT FROM AUTHOR]

The authors provide data on the taxonomic composition, structure and quantitative characteristics of zooplankton and zoobenthos from the mainstream, floodplain water bodies and side channels of the upper Lena River. A total of 76 species of plankton were recorded, including the northern relict C. scutifer, found in Lake Istok on Lena River. Judging by the structure and quantitative characteristics of zooplankton, the trophic status of these waters ranges from oligotrophic to α-mesotrophic. The zoobenthos is composed mainly of dragonfly larvae, mayflies, caddisflies and chironomids

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.

A baseline study of hard-bottom zoobenthos in relation to environmental gradients in Kongsfjorden, a glacial fjord in Svalbard, is presented, based on collections from 1996 to 1998. The total species richness in 62 samples from 0 to 30 m depth along five transects was 403 species. Because 32 taxa could not be identified to species level and because 11 species are probably new to science, the total number of identified species was 360. Of these, 47 species are new for Svalbard waters. Bryozoa was the most diverse group. Biogeographic composition revealed features of both Arctic and sub-Arctic properties of the fauna. Species richness, frequency of species occurrence, mean abundance and biomass generally decreased towards the tidal glaciers in inner Kongsfjorden. Among eight environmental factors, depth was most important for explaining variance in the composition of the zoobenthos. The diversity was consistently low at shallow depths, whereas the non-linear patterns of species composition of deeper samples indicated a transitional zone between surface and deeper water masses at 15–20 m depth. Groups of “colonial” and “non-colonial” species differed in diversity, biogeographic composition and distribution by location and depth as well as in relation to other environmental factors. “Non-colonial” species made a greater contribution than “colonial” species to total species richness, total occurrence and biomass in samples, and were more influenced by the depth gradient. Biogeographic composition was sensitive to variation of zoobenthic characteristics over the studied depth range. A list of recorded species and a description of sampling sites are presented.

Feeding and growth of carp yearlings in nursery ponds of the experimental farm “Nyvka” at the directional formation of natural food base have been studied. It was found that application of methods of directional formation of natural food base, including fertilization of nursery ponds with different organic fertilizers, resulted in supplying juvenile carp with natural food. The content of live feed objects (zooplankton, zoobenthos) in carp gut in the experiment was 48.3?50.4% versus 32.6% in the control. Survival of carp yearlings from stocked non?grown larvae was higher in the experiment and composed 31.5 - 48.6% versus 21.0 in the control; fish productivity was 326.0 - 736.3 kg/ha and 232.1 kg/ha, respectively.