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The analysis of lake sediment cores have been long used as historical integrators of environmental changes. Nutrient poor isoetid lakes remain under studied in the north boreal region. Hence, the bottom sediments of two north boreal Lobelia lakes, located in NE Finland were analysed for the presence of Cladocera and Pediastrum remains. Sediment cores from the littoral zones were sampled, sectioned every centimetre and aged with 210Pb. The number of taxa of both Cladocera and Pediastrum identified in the cores was high, while the number of individuals in each taxon was low. In Lake Kevojärvi, twenty five Cladocera species and eight Pediastrum species were found. Along with widely distributed species, typical for north boreal regions, species preferring more temperate environments occurred. In Lake Petäjälampi, the species composition was similar. Twenty one Cladocera species and five Pediastrum species occurred there, however with a lower frequency of individuals in each taxon. In both Lobelia lakes, analyses of subfossil Cladocera and Pediastrum remains, from the sediments deposited within the last 30–40 years indicated a recent increase in trophic status.

Species composition of benthic and planktonic Cladocera was analysed in four lakes and ponds located in the southern part of the Spitsbergen Island near the Fjord Hornsund. This is the first study to provide information on the species composition of the contemporary and subfossil Cladocera in this region. A total of eight Cladocera taxa were found in the sediments and waters of the lakes that have been chosen for the study. The sediments included remains of only five species, while seven Cladocera species were found in the zooplankton samples. The results imply that the lakes are subject to natural transformations driven by the fluctuating climate which was reflected by increasing the number of species, and in particular in the appearance of Bosmina longirostris. Absence of some littoral Cladocera species in the sediments (e.g., small Alona, Ophyroxus gracilis), with simultaneous occurrence of these species in the water, may be a result of physical and chemical processes influencing the destruction and lack of preservation of the remains in the sediments.

Stability analysis of a levee made of the bottom sediments from Czorsztyn-Niedzica Reservoir is presented in the paper. These sediments were classified as silty sands and, based on the authors' own research, their geotechnical parameters were beneficial, so the possibility of using this material for the hydraulic embankments was considered. Stability and filtration calculations were carried out for a levee that had the same top width - 3 m, slope inclinations 1:2 and different heights: 4, 6 and 8 m. Two methods were used: analytical and numerical. Calculations were carried out without and with a steady and unsteady seepage filtration. Based on the analysis carried out it was stated that the levee made of the bottom sediments is stable even at the height of 8.0 m, although because of the seepage on the downstream side it is recommended to use a drainage at the toe of the slope.

The aim of the study was to determine the geotechnical characteristics of the unburnt colliery spoils after coal-recovery from the dumping site of one of the mines of the Upper Silesian Coal Basin in Poland. Due to grain-size distribution of tested spoils their geotechnical properties were determined using medium-sized apparatuses. In order to verify the suitability of the studied spoils for the construction of hydraulic embankments, the seepage and stability calculations were conducted for models of hydraulic embankments including the effect of flood wave passage on stress conditions within the construction and their slope stability. The test results revealed, that the studied colliery spoils are characterized by favourable values of geotechnical parameters and they fulfil the requirements for soil materials used in the analysed type of constructions. The spoils are characterized by good compactibility, relatively low water permeability and average susceptibility to mechanical disintegration, which in the case of using this material for the construction of hydraulic embankments and using proper compaction technology, should reduce their susceptibility to weathering. The results of seepage and slope stability calculations for hydraulic embankments built of the studied spoils confirmed their suitability for that type of constructions, retaining the proper inclination of slopes, whereas the variant of embankment without sealing is safer from the stability viewpoint.

Plastic debris is thought to be widespread in freshwater ecosystems globally 1 . However, a lack of comprehensive and comparable data makes rigorous assessment of its distribution challenging 2,3 . Here we present a standardized cross-national survey that assesses the abundance and type of plastic debris (>250 μm) in freshwater ecosystems. We sample surface waters of 38 lakes and reservoirs, distributed across gradients of geographical position and limnological attributes, with the aim to identify factors associated with an increased observation of plastics. We find plastic debris in all studied lakes and reservoirs, suggesting that these ecosystems play a key role in the plastic-pollution cycle. Our results indicate that two types of lakes are particularly vulnerable to plastic contamination: lakes and reservoirs in densely populated and urbanized areas and large lakes and reservoirs with elevated deposition areas, long water-retention times and high levels of anthropogenic influence. Plastic concentrations vary widely among lakes; in the most polluted, concentrations reach or even exceed those reported in the subtropical oceanic gyres, marine areas collecting large amounts of debris 4 . Our findings highlight the importance of including lakes and reservoirs when addressing plastic pollution, in the context of pollution management and for the continued provision of lake ecosystem services., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

The Bełchatów Lignite Mine of Poland is a treasure-cove for mid-to late Miocene plant and animal fossils, deposited in a slow-flowing river valley with swamps and oxbow lakes. Here, we report the finding of abundant fossil anomopod cladocerans. Some are three-dimensionally preserved, including the taxonomically important trunk limbs. They pertain to the families Chydoridae and Bosminidae, with species similar to but distinct from modern ones. All are members of the zooplankton, though some are littoral while others are pelagic in nature. Morphological stasis in these families is not outspoken as in the Daphniidae and the stasis hypothesis, based on ephippia only, is challenged. The absence of Daphnia is conspicuous and ascribed to a combination of fish predation and local water chemistry. Its place in the oxbow lakes is taken by at least two Bosmina species, one of which is undescribed. We consider this a case of paleo-competitive release. For Bosminidae, these are the first certified fossils predating the Pleistocene.

Cladoceran communities of two lakes of Nevado de Toluca Volcano, Central Mexico, were studied. A new species of Aloninae, Alona manueli sp. nov., is described. It was previously confused with Palearctic Alona intermedia Sars, 1862, but clearly differs from it in the morphology of postabdomen, head shield and head pores, and thoracic limbs. Position of Alona manueli sp. nov. within the genus is unclear, it did not belong to any species-group within Alona s. lato. Other species recorded in the studied lakes are Alona ossiani Sinev, 1998, Alonella pulchella Herrick, 1884, Chydorus belonging to sphaericus-group, Eurycercus longirostris Hann, 1982 and Pleuroxus cf. denticulatus Birge, 1879.

Introduction: Allergic sensitization of the airways occurs not only in the mucosa of the shock organ, but also in the lymphatic stations draining these structures. The lymphatic structure closest to the nasal mucosa in humans is the adenoid. Many researches show that in part of children allergic rhinitis can be a risk factor for adenoid hypertrophy., Materials and Methods: We used acoustic rhinometry and endoscopy to evaluate the influence of the birch pollination on the adenoid size in 67 children between 5 and 12 years old. Four separate groups of children were examined. The study group consisted of 28 children hypersensitive to tree pollen with seasonal allergic rhinitis (interview, positive skin prick test results, presence of sIgE in the serum and positive nasal provocation test with birch pollen allergens). The first control group consisted of 14 atopic children hypersensitive to motherwort pollen. The second control group consisted of 15 non-atopic children. The third control group consisted of 10 children hypersensitive to tree pollen, they have got anti-allergic treatment (topical nasal steroid and antihistaminic) a week before birch pollination. In all of the groups the adenoid size was examined before, during and after birch pollination. In the study group, we examined the influence of specific nasal provocation test on the adenoid size too., Results: In most children from the study group (71.4%) we observed the significant increase of adenoid size in endoscopic examination and decrease of nasopharyngeal cavity volume in acoustics rhinometry (92.9%) during the birch pollination. The changes returned after pollination period in most children (90%). In the first and the second control group there were almost no changes observed (p>0.05). The medical treatment used in the third control group avoided the increase of adenoid size during birch pollination season. In the study group there was no statistically significant correlation between the changes in nasopharyngeal volume during the pollination period and the results of nasal provocation test (r=0.18)., Conclusion: The result of our study suggests that in children with seasonal allergic rhinitis the exposure on the allergenic factor can influence the adenoid size. Properly administered nasal glucocorticoid together with antihistaminic in standard doses can probably avoid this effect.

Introduction: The adenoidectomy is the most often made operation in small children but the reasons of adenoid hypertrophy are not completely explained. Some researches show that in part of children, allergy can be a risk factor for adenoid hypertrophy. The main aim of this study was the analysis of adenoid hypertrophy in children with different allergic diseases., Material and Methods: Two separate groups of children were examined. The study group consisted of 436 children between 4 and 9 years old with allergic rhinitis and/or bronchial asthma and/or atopic dermatitis hypersensitive to house dust mites (interview, positive skin-prick test results). The control group consisted of 229 non-atopic children (negative interview and skin-prick tests) in the similar age. In the both groups we examined the incidence of adenoid hypertrophy and its dependence of the kind of allergic disease, age, sex, infections, results of skin-prick test and other sensitization., Results: The probability of adenoid hypertrophy was statistically more significant (logistic regression analysis) only in children from the study group with allergic rhinitis. There were no differences in adenoid hypertrophy incidence between children with other allergic diseases and the control group. The children from the study group with adenoid hypertrophy were more often hypersensitive to pollen and moulds allergens than the children without adenoid hypertrophy (chi square test). But there were no differences in the incidence of infection, age, sex and results of skin-prick tests., Conclusion: The result of our study suggests that the chance of adenoid hypertrophy in allergic children hypersensitive to dust mites is greater only in them with allergic rhinitis.

Unlabelled: Although adenoidectomy is the most frequently performed surgical operation in small children, the causes of adenoid hypertrophy are not completely explained. Certain studies indicate that in some children it is an allergy that can constitute a risk factor for adenoid hypertrophy. The main aim of this study was the analysis of atopic allergy in children with adenoid hypertrophy., Material and Methods: Two separate groups of children aged between 4 and 10 years with nasal obstruction were examined. The study group consisted of 796 children with adenoid hypertrophy. The control group consisted of 297 children without adenoid hypertrophy. In all of the children a skin prick test was performed and the frequency of occurrence of typical allergic diseases was estimated., Results: The skin prick test was positive in about 19% of children in both groups under examination (no statistical differences). In children from the study group the allergic rhinitis occurred significantly more often than in the group without hypertrophy (p = 0.0000). The hypersensitivity to dust mites was demonstrated in the study group more often as well (p = 0.0007). The results were confirmed by logistic regression. There were no differences in the frequency of atopic dermatitis and bronchial asthma between both groups compared., Conclusions: In children with adenoid hypertrophy allergic rhinitis was the most commonly found allergic disease which seems to be the risk factor for adenoid hypertrophy in hypersensitive children.

Background: Allergic rhinitis is considered a risk factor for bronchial asthma. It therefore seems essential to identify patients threatened with this disease in whom no disturbing bronchial symptoms have occurred. The study's aim was to evaluate the incidence of nonspecific bronchial hyperactivity based on exercise results in pollinosis patients., Material/methods: The study group comprised 27 patients with seasonal allergic rhinitis allergic to tree pollens but without asthma symrptom. Exercise provocation tests were performed before, during, and after completion of the pollination period. During the pollination period, specific IgE (sIgE) and nasal eosinophilia were also determined. Twelve patients allergic to Artemisia pollen made up the control group. The results were also evaluated in relation to desensitization therapy., Results: In the study group a pathological result of the provocation test was obtained in 1 patient (3.7%) before the pollination period, in 7 patients (25.9%) during, and in 4 patients (11.8%) after its completion. The subjects with a positive test result had higher levels of nasal eosinophilia, while there was no relation between the result and sIgE levels. Only one case of positive exercise challenge was identified among the desensitized patients., Conclusions: During the pollination period, nonspecific bronchial hyperreactivity develops in some patients with seasonal allergic rhinitis; it can be sustained for some time after the disappearance of pollens from the atmosphere and can he identified using an exercise challenge. Incidence of bronchial hyperreactivity in desensitized patients was lower than in those subjected to symptomatic treatment.

Unlabelled: The adenoidectomy is the most often made operation in small children but the reasons of adenoid hypertrophy are not completely explain. Some researches show that in part of children allergy can be a risk factor for adenoid hypertrophy. The main aim of this study was the analysis of adenoid hypertrophy in children with different allergic diseases., Material and Methods: Two separate groups of children were examined. The study group consisted of 436 children between 4 and 9 years old with allergic rhinitis and/or bronchial asthma and/or atopic dermatitis hypersensitive to house dust mites (interview, positive skin-prick test results). The control group consisted of 229 non-atopic children (negative interview and skin-prick tests) in the similar age. In the both groups we examined the incidence of adenoid hypertrophy and its dependence of the kind of allergic disease, age, sex, infections, results of skin-prick test and other sensitisation., Results: The probability of adenoid hypertrophy was statistically more significant (logistic regression analysis) only in children from the study group with allergic rhinitis. There were no differences in adenoid hypertrophy incidence between children with other allergic diseases and the control group. The children from the study group with adenoid hypertrophy were more often hypersensitive to pollen and moulds allergens than the children without adenoid hypertrophy (chi square test). But there were no differences in the incidence of infection, age, sex and results of skin-prick tests., Conclusion: The result of our study suggests that the chance of adenoid hypertrophy in allergic children hypersensitive to dust mites is greater only in them with allergic rhinitis.