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Peatlands, shaped by centuries of human activities, now face a primary threat from mining activities. Vulnerable to drainage and hydrological instability, peatland areas encounter challenges that compromise their ecological integrity. This study hypothesised that permanent water reservoirs within mines could serve as refugia for water beetles from adjacent areas prone to drying in the summer. Employing standard methods, including entomological scraping and water traps, samples were collected. Results revealed that, in most cases, water beetles exhibited a preference for the Nature 2000 area untouched by mining. Despite unfavourable conditions, the Nature 2000 area showcased a more diverse water beetle fauna. Remarkably, the selected Nature 2000 area, despite its identified degradation based on flora, remained a biodiversity hotspot for peatland water beetle fauna. The study underscores the significance of assessing insects, particularly beetles, as rapid responders to environmental changes. This evaluation holds crucial implications for peatland restoration planning and decision-making regarding mining investments in proximity to peatland areas. [ABSTRACT FROM AUTHOR]

This study examined the availability of food and its selection by sea trout Salmo trutta L. fry in the first four weeks of life after yolk sac resorption. The food base and stomach contents of sea trout fry after release in the wild were determined. The study was performed in two small forest streams from April 25 to May 23, 2014. Macro-zoobenthos that comprised the food base for the fry were collected from the streams weekly using a bottom scraper. On the same day, the fry were captured with electrofishing gear. Analysis of the width of the benthic organisms in the food base and in the fish stomachs indicated the prey size range that the fish were feeding on. Further, the study showed that all food items found in both streams during the study weeks were also represented in the intensity of the fish: Cyclopoida, the larvae of Baetidae, Simuliidae and Nemouridae.

The main objective of this study was to examine the spatial distribution patterns of aquatic invertebrates in an environment characterized by significant anthropogenic stress. During the entire research period, at all the sites, we noticed 72 taxa of zooplankton and 30 taxa of macroinvertebrates. Variation partitioning analysis reveals that the assemblages of planktonic organisms are much more determined by the time of sampling rather than by the site, in contrary to macroinvertebrates where the sampling time was only slightly more responsible for the composition of the benthic communities than the site. Spatial distribution of aquatic organisms in a small lowland river under strong anthropopressure shows significant deviations from the expectations of the River Continuum Concept (RCC). The benthic macroinvertebrate and littoral zooplankton communities exhibited a strong association with local site conditions, while, in contrast, pelagic zooplankton exhibited a strong dependency on drift and its production in the upper reaches of the river, leading to relatively consistent compositions downstream despite the highly altered river environment. To improve the biodiversity values and ecological state of a river, restoration treatments of bed and shore zones are required. [ABSTRACT FROM AUTHOR]

In studies of abiotic and biotic factors influencing macroinvertebrate assemblages, there is always the problem of which factor – fish predation or environmental conditions – has the strongest impact on the invertebrates and whether the impact is positive or negative. The aim of our study was to determine the impact on the structures of macrozoobenthos in a small field watercourse exerted by abiotic conditions, with the concurrent lack of predators and varied intensity of anthropopressure. During the entire study period, the presence of 49 taxa of macroinvertebrates was recorded. The highest number of taxa and value of biodiversity was observed in the upper part of the watercourse, and subsequently decreased down the stream, reaching the lowest value at the sites located near the outlet. The tributaries significantly differed between each other in the number of taxa. In the tributary carrying water from wetland, a much higher number of taxa was noted than in the tributary carrying municipal water where the density achieved a significantly higher value of individuals than the remaining sites. The most limiting factors for the abundance of the investigated taxa were the oxygen concentration, nutrients and ammonia.

The aim of study was to evaluate the effects of the live diet and pellet diet on the survival and growth rates of the stocking material of nase fry. The rearing was performed in two variants: live-fed group (LFG) and pellet-fed group (PFG) - larvae fed on prepared food starter. The LFG were reared on similar food that occurred in a stream designed for the stocking in each week of the experiment (zooplankton, chironomids larvae and periphyton). In the beginning of rearing, the PFG were characterized by higher values of total length, mass than those from the LFG. After supplementation with periphyton for the LFG, the values of total length and mass of the LFG were higher than those of the PFG. Our results show that the rearing of the nase fry on natural food may lead to them obtaining satisfactory growth rates. [ABSTRACT FROM AUTHOR]

The aim of this study was to make a comparative analysis of macrozoobenthos composition at different sites at selected sections of lower the Odra River with relation to different physicochemical factors. The observations were made on the lower section of Odra River at five study sites: two of them were localized in the main channel, one in the left branch of river, another one in the channel carrying post-cooling water from Dolna Odra power plant, and the last one was in the channel connecting both branches of Odra River. At all sites, 26 taxa were found representing by: Bivalvia, Gastropoda, Oligochaeta, Hirudinea, Malacostraca and Insecta. The greatest biodiversity and the highest abundance of zoobenthos organisms were noted in the channel joining the two branches of the river, site 5, characterised by the lowest water flow rates and the densest coverage of the macrophytes at the bottom. Temperature was the sole parameter to be studied that affected the composition of benthic invertebrates. A clearly negative impact of temperature on the diversity of invertebrates was observed only in the channel with post-cooling water discharged from the power plant. [ABSTRACT FROM AUTHOR]

Fish occurring in the outlets of water basins reduce the abundance of zooplankton. The study was performed at the outlet sections of the lake and waste stabilization pond of a sewage treatment plant. The aim of the study was to determine which zooplankton is chosen more often by the roach (Rutilus rutilus), those drifting from the waste stabilization pond or from the lake. The zooplankton from the pond was dominated by Daphnia pulex while zooplankton from the lake was dominated by small planktonic rotifers. We observed that the larger the plankter-victim's size, the faster the reduction of its number. The fish were more likely to feed on zooplankton drifting from the waste stabilization pond than from the lake. It was influenced by D. pulex individuals, attractive for fish due to their largest body size among the analyzed zooplankton. The significance of riverine zooplankton in the downstream food web may render this data even more important. [ABSTRACT FROM AUTHOR]