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Franz Josef Land (FJL) is a remote archipelago that has become more accessible for large-scale studies due to recent warming. This paper summarizes recent survey findings on oceanography, climate, plankton, and benthic communities conducted in FJL. Cold Arctic waters predominantly affect FJL, but an increased inflow of warmer Atlantic water has been observed in recent decades. The bacterioplankton in FJL is mainly comprised of ultra-small bacterial cells, which make up to 60% of the biomass. Phytoplankton are predominantly composed of cells smaller than 20 μm, with the greatest concentrations found above the pycnocline. The population of larger microalgae ranges from 4.5 to 1250 thousand cells L−1, with dinoflagellates occupying the euphotic zone, Dinobryon being the most abundant species in the thermocline, and spore-bearing cells of Chaetoceros diatoms dominating in the deepest region. Summer zooplankton comprise large Calanus copepods, smaller copepods, and meroplankton, with an average dry biomass of 114–391 mg m−3. The community structure varies mainly based on water temperature and phytoplankton density, with greater biomasses found in colder offshore waters. August represents the breeding season for plankton populations. The local benthic fauna is diverse and displays high species abundance (3370 ind. m−2) and wet biomass (428 g m−2). There is a distinct vertical stratification in the benthic community structure, evidenced by a consistent decline in both abundance and biomass with increasing depth. The trophic structure is predominantly influenced by food availability, sediments, and currents. The trend of borealization in the Barents Sea biota is supported by recent distribution records of certain boreal benthic species and increased abundances of typical Atlantic zooplankton species. The results of our study establish a foundational dataset to aid in ongoing scientific inquiry, preservation efforts, and strategic decision-making with regards to the natural resources of the FJL region. • The area has a complex oceanography and is influenced mainly by Arctic Water. • Clear spatial and vertical patterns are common in the local biota. • Plankton abundance and biomass peak in August. • Benthic fauna shows high species diversity, abundance, and biomass. • Warming has led to increased taxa abundances and borealization of the fauna. [ABSTRACT FROM AUTHOR]

Species-area relationships (SAR) for aquatic invertebrates and phytoplankton were investigated in several shallow lakes from the Fizeș River catchment area. The lakes differed in their morphometric, physical-chemical, biotic and habitat characteristics, with two constant distinctive clusters: the lakes from the main river course, highly exploited for fish farming and generally characterized by higher organic and nutrient loads, and the lakes from the river tributaries, with better environmental conditions, increased depth and lower exploitation intensities. Lake area was a poor predictor of taxon richness for lacustrine invertebrates. Low-intensity exploitation regime, the presence of submerged vegetation, lake depth and natural land use in the catchment area represented the most important independent variables explaining the number of taxa for both planktonic and benthic invertebrates. In case of phytoplankton, however, lake area was an important predictor for taxon richness. Our results represent the first holistic approach to investigating SAR patterns of aquatic biota in natural and man-made lakes from the region. [ABSTRACT FROM AUTHOR]

The article presents data on the activity of the radionuclide 137Cs in seawater, sediment, macroalgae, and zoobenthos from different locations in Admiralty Bay, King George Island, maritime Antarctica. The activity of 137Cs in the macrophytobenthos remained relatively stable across species, oscillating at the level of 1 Bq kg−1dw. However, a few individuals exhibited higher activity, particularly at stations closer to the glacier front. This result could have been caused by specific conditions resulting from melting glaciers and meltwater inflow and mixing with oceanic water. The activities of 137Cs in zoobenthic were in the range from 0.12 Bq kg−1dw (Asteroidea) to 24.2 Bq kg−1dw (Porifera) and the total doses in marine species were several orders of magnitude lower than reference levels. Stable isotopes of δ13C and δ15N suggest that the main factor influencing 137Cs activity may be the source of carbon (marine vs. terrestrial/glacial), rather than feeding strategy or trophic niches. [Display omitted] • 137Cs in Antarctic biota were still detected. • Low activity of 137 Cs is observed in most cases of the Antarctic ecosystem. • Carbon cycling may affect radionuclides activity in zoobenthos. • Total dose from 137Cs in Antarctic species was negligible. [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.)

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]

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.)

An intensification of industrial development of the Republic of Sakha (Yakutia) involves the Kankunskaya hydropower plant construction project, implementation of which would have a drastic impact on the ecological state of surface waters within the Timpton River basin. A necessary stage of all pre-construction survey work is the initial environmental state assessment. In this regard, a study of baseline hydrochemical and hydrobiological state of water, including an investigation of phytoperiphyton and benthic fauna, has been carried out. As a result, it has been found a low salinity of waters, a small nutrients' content, and an increased heavy metals' content. It has been discovered 12 new species of algae for the water bodies of Yakutia and 92 new species in the Aldan River basin. The modern composition of the benthic fauna includes 8 taxonomic groups, the dominant position is occupied by the larvae of caddisflies and chironomids. The quantitative parameters of the zoobenthos of the watercourses of the Timpton River are low: during the study period, the biomass varied within 0–0.9 g/m2 at a density of 0–72 ind./m2. [ABSTRACT FROM AUTHOR]

The article focuses on the issues concerning the development of the multitrait concept for functional diversity in biological traits of species. It highlights the negligence of empirical evaluation such as body size of the species while studying the linkage between numerical and functional traits diversity and reports that only functional diversity is considered.

The article focuses on a study concerning the scale-dependent distributional patterns in soft-bottom macrofaunal communities of naturally low species richness found on Åland Islands in the northern Baltic Sea in Europe. The sampling design of the study is discussed in which three spatial surveys consisting of identical sampling set-ups have been conducted in June 2001 leading to a total number of 192 benthic samples. One finding of the study shows that 10 of the 29 species were found in Area I while 19 and 23 species were identified in areas II and III, respectively. It adds that the study stresses the importance of cross-scale studies in environmental monitoring, analysis of the impact of natural and anthropogenic perturbations and marine conservation.

This article discusses a study which examined the assemblage patterns of the Peracarida, a crustacean, on different vegetation types in the Qi'ao-Dan'gan Island Mangrove Nature Reserve on Qi'ao Island in the Pearl River Estuary, China. The study investigated the patterns, including composition, abundance and diversity, and the relationship of the assemblages to different types of fauna. It applied quantitative sampling from January 2007 to November 2008. The study found higher abundance of the Peracarida in both the mangrove arbor and seaweed.

Abstract: The structure of the macrozoobenthic community in 2003–2004 in the southern part of the Onega Bay along a salinity gradient showed the poorest fauna (one species) was found in the estuarine area. In the open part of the bay the species richness up to 64 species. In the study area, as a whole, the zoobenthos abundance varied from 51 to 4590ind.m−2, biomass – from 0.51 to 651.4gm−2 and lower values occurred in the estuarine part of the Onega Bay. The Shannon diversity index [log2 basis] varied considerably – from 0.69 bits in the mouth of the Onega River up to 4.56 bits at the marine stations. Liner multiple regression analysis showed that species richness is related primarily to depth, distance, temperature and the amount of C org. in sediments; Shannon diversity is connected with salinity, temperature, depth, amount of C org. in sediments and chlorophyll concentration in the water. For abundance and biomass the main determining factors were distance and concentration of C org. in sediments. Fresh water input from the Onega River caused variations in the salinity regime in the top of the Bay which indirectly influenced zoobenthic populations via other parameters which changed as a result of river discharge. [Copyright &y& Elsevier]

Abstract: The Neva Estuary situated in the eastern Gulf of Finland is one of the largest estuaries of the Baltic Sea with a large conurbation, St. Petersburg, situated on its coast. Eutrophication, alien species and large-scale digging and dumping of bottom sediment are the most prominent anthropogenic impacts on its ecosystem. However, many ecosystem responses, which are traditionally attribute to these impacts, are related to natural dynamics of the ecosystem. Fluctuations in discharge of the Neva River, intrusions of bottom hypoxic waters from the western part of the Gulf of Finland, higher summer temperatures and a shorter period of ice cover are climatic mediated factors inducing adverse changes in its ecosystem from the 1980s onwards. The main ecosystem responses to these factors are 2–3-fold increase of trophic status, deterioration of native zoobenthic communities and establishment of alien species, as well as the many fold decrease of fish catch and the population of ringed seal in the region. [Copyright &y& Elsevier]

The niche width and niche overlap of macrozoobenthos dominant species in the intertidal zone of Jiaojiang Estuary in October 2007 were analyzed based on niche theory, and the effects of natural factors (salinity, water temperature, sediment temperature, beach width, and sediment grain size) and environmental factors (contents of oils and heavy metals) on the environmental heterogeneity as well as the relationships between selected environmental factors and quantitative distribution of various groups of macrozoobenthos were studied by using canonical correspondence analysis method. The macrozoobenthos dominant species in study area were classified into four groups, i.e., burrowing surface predator, surface grazer, subsurface filter feeder, and subsurface swallow feeder, based on their feeding types. There were great differences in the niche widths among the groups, with the maximum of 0.428 and the minimum of 0.168, which suggested that different groups had different adaptive capacity to the environmental factors. At the level of niche overlap value higher than 0.6, Macrophthalmus japonicas and M. definitus of Group 1, Lunatica gilva, Bullacta exarata, Decorifera insignis, Assiminea brevicula and Cerithidae ornate of Group 2, and Moerella iridescens, Glauconome chinensis and Potamocorbula laevis of Group 3 had a biologically significant niche overlap, indicating their similar behavior in utilizing natural feeding resources. [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.)

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.)

An assessment of the trophic status of Lake Mogan, which is an important recreation area for the city of Ankara, was carried out utilizing data collected between December 2001 and January 2003. The data include water quality parameters, dominant plankton and zoobenthos taxa. The trophic status of Lake Mogan is considered to be mesotrophic/eutrophic. This conclusion is consistent with the results of earlier studies. [ABSTRACT FROM AUTHOR]

Surveys of the benthic macroinvertebrate community were conducted in the main basin of Lake Huran in 2000 and 2003, and in Georgian Bay and North Channel in 2002. Results were compared to surveys conducted in the 1960s and early 1970s. Although data of earlier surveys were inconsistent, our best estimates suggest that total density of the four major benthic taxa (Diporeia spp., Oligochaeta, Sphaeriidae, and Chironomidae) in the main basin declined dramatically between the early 1970s and 2000. Populations of all major taxa continued to decline between 2000 and 2003, particularly Diporeia and Sphaeriidae. Diporeia was rare or absent in the southern end of the lake and in some nearshore areas in 2000, and by 2003 was not found at depths < 50 m except in the far northeastern end of the lake. Densities of the major taxa in Georgian Bay and North Channel in 2002 were not different from densities in 1973 despite differences in survey methods. A limited study in southern Georgian Bay, however, found that densities of both Diporeia and Sphaeriidae declined to zero at most sites between 2000 and 2004. The population of Dreissena polymorpha was stable in all lake areas, but Dreissena bugensis increased, particularly at the 31-50 m depth interval in the main basin. Since there were no extensive surveys in Lake Huron in the period between nutrient abatement (late 1970s) and the establishment of Dreissena (early 1990s), it is difficult to determine relative roles of these events on observed declines. However, since phosphorus loads have been stable since the early 1980s, declines between 2000 and 2003 can likely be attributed to Dreissena. [ABSTRACT FROM AUTHOR]

Abstract: The macrofauna in the north Marmara Sea were identified and evaluated with univariate measures and biotic indices (BENTIX, AMBI). As expected, the diversity and species’ variety decreased as the sediments became muddier and as the stress increased. The AMBI index failed to detect the spatial differentiation of the EcoQ between the sites whereas, the BENTIX index succeeded (in 70% of the cases) in producing an ecologically relevant classification reflecting the environmental pressures. Results suggested that risks of reduced species’ richness and diversity from organic loading and other associated stressors in sediments should be relatively low at TOC concentrations < about 6mg/g, high at concentrations>about 22mg/g, and intermediate at concentrations in-between. It is suggested that these TOC critical points may be used as a general screening-level indicator for assessing the EcoQ in association with reduced biodiversity over coastal areas receiving organic wastes and other pollutants from human activities. It is further suggested that both assignment of species to ecological groups and classification scales for biotic indices (AMBI, BENTIX) for sites in the Mediterranean Sea should be readjusted so as to be closer related to environmental variables. [Copyright &y& Elsevier]

The article discusses the hydrobiological indicators of toxification of ponds of the western region of Ukraine. In the Western region of Ukraine the technogenic effect on the river basin systems, within the limits of which the ponds are located, results in disruption of the dynamic equilibrium of landscape complexes that causes instability of the ecological situation. The region is characterized by a high population density, sometimes a deficiency of water resources, and predominantly shallow rivers. The large scales of regulated surface runoff, high degree of tilled soil in floodplain meadows, all these factors promote degradation of aquatic ecosystems in the region.

Many remote montane ecosystems are experiencing biogeochemical changes driven by warming climate and atmospheric pollution. Compared with circumpolar and temperate lakes, the responses of subtropical montane lakes to these external stressors have been less investigated. Here we present sedimentary multi-proxies records (i.e. chironomids, elements and stable isotope of carbon and nitrogen) in 210Pb-dated cores from two montane ponds (central China). Before the 1900s, low biomass and the dominance of opportunistic species (e.g. Chironomus anthracinus -type) in both ponds might be in response to cold and harsh condition. Thereafter, chironomid communities in both ponds experienced pronounced shifts. Nutrient-tolerant/warm-adapted species (e.g. Chironomus sp., Polypedilum nubeculosum -type and Endochironomus impar -type) proliferated and biomass increased synchronously after the 1900s, suggestive of favorable condition for chironomid growth. Redundancy analyses revealed that changes in chironomid communities in both ponds were significantly correlated with rising temperature and δ15N depletion. Prolonged growing season and nitrogen subsidy would increase primary productivity, and hence enhancing food availability for chironomids. Catchment-mediated indirect effects of warming and nitrogen deposition, such as hydrological changes and terrestrial organic matter inputs, would impose further influences on chironomid communities. Taken together, the combined effects of climate warming and nitrogen deposition have caused significant shifts in primary consumers of these montane ponds, and imposed cascading effects on structure and function of subtropical montane aquatic ecosystems. Image 1 • Chironomid and geochemistry records were retrieved from subtropical alpine ponds. • Nutrient-tolerant/warm-adapted chironomid species proliferated after the 1900s. • Shifts in chironomid communities were closely related to δ15N depletion and warming. • Subtropical montane aquatic ecosystems are sensitive to warming and nitrogen input. The main finding of the work: Climate warming and nitrogen deposition lead to shifts in chironomid communities of subtropical montane ponds. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Abstract: The introduced collecting method is based on a common entomologist exhauster, which is specified for the fieldwork in aquatic systems with a sieve-inset and a bottom-lid. The living organisms are collected visually from the sampled debris and no further extraction is needed. The apparatus is designed for qualitative sampling of microcrustaceans (e.g. Cladocera, Copepoda, Ostracoda) and minimises disturbance at the sampling site. [Copyright &y& Elsevier]