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Number of results: 23
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Abstract

Dratów, Krzczeń and Tomaszne lakes are linked by means of Wieprz-Krzna Canal. On the other hand, Bikcze, Mytycze and Plotycze lakes are not included in the water system of Wieprz-Krzna Canal. However, all these lakes are regarded as biologically valuable water reser-voirs forming Łęczyńsko-Włodawskie Lakeland. They are shallow eutrophic lakes with varied water surface, different catchment area and diversified structure of catchment management. The qualitative and quantitative composition of planktonic rotifers was studied in spring, summer and autumn of 2012 and 2013. The studies revealed the presence of 67 Rotifera species with their mean density ranging from 119 ind. dm-3 in Tomaszne lake to 1441 ind. dm-3 in Bikcze lake. Dominants included few very common species of Brachionus angularis, Keratella cochlearis, Keratella cochlearis tecta, Keratella quadrata, Polyartchra vulgaris. Dominance structure and species diversity suggest a slightly higher ecological status of Mytycze lake, as compared to the remaining eutrophic reservoirs. Faunistic differences observed among rotifer assemblages inhabiting individual lakes were significantly bigger than those registered in the successive study years within the area of individual lakes. This property referred to all the reservoirs, both the ones linked with the water system of the canal and the lakes not included in the canal system. Bigger faunistic differences occurred among rotifer assemblages inhabiting the lakes of Wieprz-Krzna Canal sys-tem, as compared with the assemblages found in the lakes not included in the system.
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Abstract

The Hoglandvatnet and Ålandvatnet are genetically associated with the action of a large ice stream issuing from Mittag-Lefflerbreen towards Lomonosovfonna as far nortwards as Austfjorden. The accomplished investigations permit water properties to be described for Hoglandvatnet and Ålandvatnet, as well as the chemical composition of the basin waters to be correlated with lithologic diversity of the surrounding massifs and the composition of glacier water feeding them. Water of Hoglandvatnet has a rather uniform ion composition. It is sulphate-calcium water. Low mineral contents of glacier water and that flowing through crystalline rocks of Framstaken and feeding the basin result in its less marked effect on the Hoglandvatnet water, compared with highly mineralized water of streams issuing from Trikolorfjellet and Tarantellen. Water of Ålandvatnet has a somewhat different quantitative ion composition than that of Hoglandvatnet. It is calcium-sulphate-bicarbonate water which is richer in the bicarbonate ion than the Hoglandvatnet waters. This is most likely due to the influence of bicarbonate water of Ålandelva and glacier water feeding the basin. It can also be the result of a smaller contribution from highly mineralized calcium-sulphate water issuing from Trikolorfjellet.
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Abstract

This article presents some cultural, historical and linguistic insights on the names of the Szczutowskie and Urszulewskie Lakes, both situated in the historical Dobrzyńskie Lakeland, today on the border between the Mazovian and Kuyavian-Pomeranian Voivodeships (the historical border between Polish and Prussian-Teutonic states). The author also takes into account the description of the local place and terrain names, showing a common relation with the natural landscape, in which the two lakes are immersed.
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Abstract

This phytoplankton study was conducted from May to September 2002, 2003 and 2005 during fountain-based water aeration in the pelagial of Jeziorak Mały urban lake in Poland. Differences in the abundance and biomass of phytoplankton groups (cyanobacteria, diatoms, chlorophytes, dinoflagellates, chrysophytes and cryptomonads) related to physico-chemical water parameters were analyzed at the fountain and in the lake centre. Fountain water-mixing changed phytoplankton growth likely by decreasing water temperature, oxygenation and nutrient concentrations. These induced a disturbance in the cyanobacteria and stimulated growth of phytoplankton groups in the water column. High phytoplankton abundance at 1 m depth at the fountain could relate with phytoplankton sinking in the water column. This additional water mixing also intensified sedimented organic matter decomposition, thus enhancing nutrient uptake by phytoplankton. These results are important for future shallow urban lake management.
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Abstract

The aims of this study were to identify the taxonomic diversity and abundance of psammonic ciliate communities in mesotrophic and eutrophic lakes (Łęczna-Włodawa Lakeland, eastern Poland). The effect of selected physical and chemical water parameters on ciliates community was also analysed. Psammon samples were collected during three seasons: spring, summer and autumn of 2010. In each lake, in the psammolittoral, samples were collected in the euarenal, higroarenal, and hydroarenal zones. A total of 53 ciliate taxa were recorded. The highest value of the Shannon-Weaver index was recorded in summer in eutrophic lake (2.79). At the same time in mesotrophic lake, a lower value of the index was determined (0.79). The mean numbers of ciliates ranged from 516 ind.cm-3 in the eutrophic lake to 191 ind. cm-3 in the mesotrophic lake. In eutrophic lake, the highest number of ciliates was recorded in the euarenal (649 ind. cm-3), and the lowest in the higroarenal (425 ind. cm-3). In the mesotrophic lake, the highest average numbers were determined in the higroarenal (235 ind. cm-3), and the lowest in the hydroarenal (155 ind. cm-3). Irrespective of the lake trophy, Hymenostomata (Paramecium sp., Glaucoma sp., Uronema nigricans) occurred in the highest numbers (from 13 to 95%). The results demonstrated that N-NH4, P-PO4 and TOC can strongly regulate the abundance and taxonomic composition of ciliates. The strongest correlations between numbers of ciliates and physical and chemical water parameters were observed in the higro- and hydroarenal zones of the eutrophic lake.
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Abstract

Dratów, Krzczeń and Tomaszne lakes are among environmentally valuable reservoirs in Poland and Łęczyńsko-Włodawskie Lakeland. These are shallow eutrophic reservoirs of varied water surface. What they have in common is the fact that they are linked by Wieprz-Krzna Canal. The main aim of the present study was to determine the degree of faunistic similarity between planktonic rorifer assemblages inhabiting these particular lakes. The authors were interested to find out whether linking the lakes with the canal, as well as currently applied water exchange could affect the degree of faunistic similarity occurring between these lakes. Physical and chemi-cal analyses, as well as the studies of planktonic rotifers were carried out in the spring, summer and autumn of 2012 and 2013. They included determining the qualitative composition and the density of planktonic rotifers. The studies resulted in finding 50 species of Rotifera, with mean density ranging from 75 to 855 ind. dm-3. The dominants included the common species of Keratel-la cochlearis, Keratella cochlearis tecta, Keratella quadrata, Polyarthra vulgaris, Kellicottia longispina, Brachionus angularis, Ascomorpha odalis and Synchaeta pectinata. The results re-vealed high faunistic similarity among rotifer assemblages inhabiting a particular lake in different years, and high diversification occurring between the lakes compared in the work. The analyses showed that linking the lakes by Wieprz-Krzna Canal did not significantly affect the faunistic similarity of these particular lakes.
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Abstract

The main relief features of glacier marginal zones in the region between the Billefjorden and Austfjorden comprise ice-cored moraines, outwash plains and glacial lakes. Characteristics of various types of ice-morainic ridges are given. This article presents examples of outwash fan relief. The results of palaeogeographical analysis serve as the basis for distinguishing between three principal stages of development of glacier morphology and meltwater outflow in the region between the Billefjorden and Austfjorden.
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Abstract

A sediment core, 350 cm long recovered from Młynek Lake, northern of Poland (Warmia and Masuria Region) was analyzed with respect to their content of diatoms and chrysophyte cysts. The aim was to reconstruct the lake water level and climatic changes during the past 2500 years. The recognized diatom assemblages displayed marked floristic changes along the sediment core samples. The main change in diatom composition consists of a shift from an assemblage dominated by benthic Fragilaria sensu lato species through marked intervals to a planktonic one in distinct zones. A high proportion of benthic to plankton taxa has been reported as indicative for a lowering of the lake level with long ice cover in a cold dry climate and a shift from benthic to planktonic diatom taxa reflects arising water level with longest growing season and reduced ice cover on the lake during a warm wet climate. Multivariate statistical analysis included hierarchical ascending clustering distinguished four diatom ecological groups. The analyzed core section was divided into 11 diatom zones according to a distribution of ecological groups and variation in abundance of dominant species supported by 14C data. The results displayed a developmental history of the Młynek Lake that can be divided into 6 main phases of alternating warm wet and cold dry shifts. A distinct dominance of planktonic eutrophic indicator diatoms accompanied by a low abundance of chrysophyte cysts indicates increased lake trophicity and a general trend for the increasing anthropogenic impact.
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Abstract

The last study on n-alkanes in surface sediments of Taihu Lake was in 2000, only 13 surface sediment samples were analysed, in order to have a comprehensive and up-to-date understanding of n-alkanes in the surface sediments of Taihu Lake, 41 surface sediment samples were analyzed by GC-MS. C10 to C37 were detected, the total concentrations of n-alkanes ranged from 2109 ng g−1 to 9096 ng g−1 (dry weight). There was strong odd carbon predominance in long chain n-alkanes and even carbon predominance in short chain n-alkanes. When this finding was combined with the analysis results of wax n-alkanes (WaxCn), carbon preference index (CPI), unresolved complex mixture (UCM), hopanes and steranes, it was considered that the long chain n-alkanes were mainly from terrigenous higher plants, and that the short chain n-alkanes mainly originated from bacteria and algae in the lake, compared with previous studies, there were no obvious anthropogenic petrogenic inputs. Terrestrial and aquatic hydrocarbons ratio (TAR) and C21−/C25+ indicated that terrigenous input was higher than aquatic sources and the nearshore n-alkanes were mainly from land-derived sources. Moreover, the distribution of short chain n-alkanes presented a relatively uniform pattern, while the long chain n-alkanes presented a trend that concentrations dropped from nearshore places to the middle of lake.
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Abstract

The restoration of the anthropogenic Pławniowice water reservoir with the hypolimnion withdrawal method (the Olszewski's tube) began in December 2003. The decision to restore the reservoir had been taken due to its terrible condition resulting from the hypertrophy, which had been indicated by the research from the years 1993–1998. The following paper presents the results of eight-year-long research into the formation of oxygen conditions and restoration settings. They were compared with the data obtained from the research before the restoration. Positive changes were witnessed. It was showed that grasping the changes in oxygen conditions enables the comparison of oxygen profiles in the same months in subsequent years. The ratio of anoxic water layer thickness to the oxygenated layer thickness was suggested as a factor characterizing oxygen conditions. The area described with an izooxa in the xy coordinate system was suggested as a factor [O2 mg/m2] allowing researchers to understand and describe occurring changes. It was observed that the oxygen solved in water as a result of the restoration occurred in the whole water column in the third decade of July. The oxygen concentration in the hypolimnion gradually rose in May, June and July each year. It was showed that the improvement in oxygen conditions stemmed from progressing oligotrophy of the reservoir.
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Abstract

The article presents changes in the thickness and duration of the ice cover found in the restored anthropogenic water reservoir of Pławniowice. It also defines the role the ice cover plays in the formation of the reservoir limnological cycle. Characteristic and significant changeability of the ice cover thickness and duration was observed. The changes in the ice cover demonstrate that they are cyclical but not regular. The ice cover did not always form in the analyzed period. It happened twice, i.e. in 1988 and 2007 (a gap of 20 years). The longest lake freezing period lasted 119 days. Changes in the ice cover duration also show certain periodicity. The shortest periods occurred approx. every 7 years. Maximum values of the ice cover thickness ranged between 10 and 52 cm. There is a relation between the ice cover thickness and its duration period. The rate of increase in the ice cover thickness varied between 0.296 and 3.6 cm/d. The hypolimnion removal impact on the ice cover duration period and thickness was not observed. On the other hand, the ice cover duration period affects the spring circulation duration. Thus, it has an influence on the oxygen balance of the limnic ecosystem.
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Abstract

The main scientific goal of this work is the presentation of the role of selected geophysical methods (Ground-Penetrating Radar GPR and Electrical Resistivity Tomography ERT) to identify water escape zones from retention reservoirs. The paper proposes a methodology of geophysical investigations for the identification of water escape zones from a retention fresh water lake (low mineralised water). The study was performed in a lake reservoir in Upper Silesia. Since a number of years the administrators of the lake have observed a decreasing water level, a phenomenon that is not related to the exploitation of the object. The analysed retention lake has a maximal depth between 6 and 10 m, depending on the season. It is located on Triassic carbonate rocks of the Muschelkalk facies. Geophysical surveys included measurements on the water surface using ground penetration radar (GPR) and electrical resistivity tomography (ERT) methods. The measurements were performed from watercrafts made of non-metal materials. The prospection reached a depth of about 1 to 5 m below the reservoir bottom. Due to large difficulties of conducting investigations in the lake, a fragment with an area of about 5,300 m 2, where service activities and sealing works were already commenced, was selected for the geophysical survey. The scope of this work was: (1) field geophysical research (Ground-Penetrating Radar GPR and Electrical Resistivity Tomography ERT with geodesic service), (2) processing of the obtained geophysical research results, (3) modelling of GPR and ERT anomalies on a fractured water reservoir bottom, and (4) interpretation of the obtained results based on the modelled geophysical anomalies. The geophysical surveys allowed for distinguishing a zone with anomalous physical parameters in the area of the analysed part of the retention lake. ERT surveys have shown that the water escape zone from the reservoir was characterised by significantly decreased electrical resistivities. Diffraction hyperboles and a zone of wave attenuation were observed on the GPR images in the lake bottom within the water escape zone indicating cracks in the bottom of the water reservoir. The proposed methodology of geophysical surveys seems effective in solving untypical issues such as measurements on the water surface.
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Abstract

The study included mesotrophic Lake Piaseczno, located in the Łęczna-Włodawa Lake District. The aim of the study was to evaluate changes of water vegetation of a mesotrophic lake subjected to strong recreational pressure. Specifically we sought to better understand which natu-ral landscapes and anthropogenic developments stimulate or impede macrophyte development and spread. The study was conducted in July in 1997, 2007 and 2017 in three transects: the peat-bog (northern part of the lake), the recreational area (southeast part) and the agricultural area (east). The phytolittoral zone was analyzed from the shoreline to the maximum range of macrophytes occurrence. The study included all groups of macrophytes. Macrophytes in the mesotrophic Lake Piaseczno are still subjected to successive changes. Clearly increased diversity among emergent macrophytes, while a group of submerged macrophytes decreased. The largest changes among analyzed groups of macrophytes occurred in recreational and agricultural transects. Macrophytes have increased the range of occurrence, which may be due to hydrological changes associated with raising the overall water level, thus with increasing the area of the littoral. Impoverishment of diversity among elodeids shows the processes associated with the increase in Lake trophy.
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Abstract

Polybrominated diphenyl ethers (PBDEs) levels in environmental media have increased over the last 20-25 years in the world. In aquatic environments PBDEs were found to be accumulated along food chain and Endocrine disruptors toxicity. In this study PBDEs were investigated in sediment and fish tissues from Lake Chaohu in central eastern China. There were 10 PBDEs congeners detected out of all 41 PBDEs. BDE-47 was of the highest with 5.17 ng/g in sediment and 58.47 ng/g in fish. PBDEs were evenly distributed across the surface sediment in the whole lake. It implied that the main source of PBDEs may not be an inflow river like Nanfei. Tissue distribution patterns of PBDEs in four fish species were in the order of BDE-47 > BDE-99 > BDE-100 > BDE-66 > BDE-138 > BDE-183 > BDE-154 > BDE-153. Octa- and deca-BDEs were below the detection limit. The concentrations of all PBDE congeners were higher in gills, livers, and kidneys than those in muscles and adipose tissue. Furthermore, PBDEs in different tissues had some different distribution patterns with fish size. Those discrepancies appeared to be correlated with the PBDEs pollution fluxes varying with the change of the year and their metabolism divergences in fish tissues.
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Abstract

Gala Lake National Park that has an international importance is one of the most important wetland ecosystems for Turkey. As same as many aquatic habitats, Gala Lake is under a significant anthropogenic pressure originated from agricultural activities conducted around the lake and from industrial discharges by means of Ergene River. The aim of this study was to evaluate the sediment quality of Gala Lake and Irrigation Canal by investigating some toxic element accumulations (As, B, Ni, Cr, Pb, Cd, Zn and Cu) from a statistical perspective. Pearson Correlation Index (PCI) and Factor Analysis (FA) were applied to detected data in order to determine the associated contaminants and effective factors on the system. Potential Ecological Risk Index (RI) and Biological Risk Index based sediment quality guidelines (mERM-Q) applied to detected data in order to assess the ecological and biological risks of heavy metals in the ecosystem. Also Geographic Information System (GIS) technology was used to make visual explanations by presenting distribution maps of investigated elements. According to the results of PCI, significant positive correlations were recorded among the investigated toxic elements at 0.01 significance level. According to the results of FA, two factors, which were named as “Agricultural Factor” and “Industrial Factor”, explained 86.6% of the total variance. According to the results of Potential Ecological Risk Index, cadmium was found to be the highest risk factor and according to results of Biological Risk Index, nickel and chromium were found to be the highest risk factors for Gala Lake and Irrigation Canal. As a result of the present study, it was also determined that heavy metal contents in sediments of Gala Lake National Park reached to critical levels and the system is intensively under effect of agricultural and industrial originated pollution.
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Abstract

In the present paper we show results of our research on the contents of selected heavy metals in the surface and subsurface water layers of the estuarine lake Gardno. Obtained results show that there are substantial differences between concentrations of lead, copper and zinc in surface microlayer and subsurface waters. We observed that the surface microlayer is capable of accumulating much higher amounts of these metals than the subsurface waters. Analysis of seasonal changes in heavy metal concentrations in surface microlayers and subsurface waters shows some periodicity of these changes.
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Abstract

Eighteen sediment samples from a 36 cm long sediment core retrieved from a proglacial lake (namely P 11) situated in the Schirmacher Oasis, East Antarctica, were analysed for the study of quartz grain morphology and microtexture, along with sand percentage, to reconstruct the paleoenvironmental changes in the lake during the Holocene. The age of the core ranges from 3.3 ka BP to 13.9 ka BP. The quartz grain morphology and microtexture reveal significant evidences of glacial transport along with some eolian and aqueous activities. On the basis of predominance of these signatures and the zonation from CONISS Cluster Analysis on the percentages of characteristic grain morphology and microtextures, the entire core has been subdivided into three major zones. From the paleoenvironmental perspective, it can be concluded that there is an onset of interglacial period at the advent of Holocene (12.3 ka BP), which reigned until 5.3 ka BP and thereafter, again a glacial environment prevailed until 3.3 ka BP with some variations in-between. The results indicate probable alternative colder and less colder phases in the study area, which are also well supported by the respective sand percentages in the sediments. © 2017 Polish Academy of Sciences 2017.
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Abstract

An accumulation of glacial sediments is located near Písečná village in the depression between the Sokol Ridge and Zlaté Hory Highlands NNE of Jeseník town (Eastern Sudetes). The accumulation lies at the lateral side of the mountain valley of the Bělá River and fills a preglacial palaeovalley of this river. Research combining facies analysis of outcrops, ground penetrating radar survey, interpretation drilling survey, and modelling of the preglacial relief was undertaken at the site. According to the results obtained, the upper part of the sedimentary accumulation represents a coarse-grained terminoglacial glaciofluvial delta of the Gilbert type. The development of the accumulation has dominantly been driven by the preglacial morphology. Facies typical for foresets of coarse-grained deltas represented mainly by high-density flows, cohesionless debris flows, debris falls and less common low-density flows were found in the outcrops. The delta near Písečná prograded into a lake dammed by the ice-sheet front in the north. The lake was bounded by the slopes of Sokol Ridge, Zlaté Hory Highlands and Góry Parkowe on other sides. The lake level reached an altitude of up to 430 m a.s.l., as the coarse-grained delta plain base lies at this level.
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