43 research outputs found

    Co-occurrence pattern of ground beetle (Coleoptera, Carabidae) assemblages along pollution gradient in scotch pine forest

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    Over the last 30 years there has been a great deal of interest in investigating patterns of species co-occurrence across space and time, which may be shaped by interspecific competition for shared resources. A good model of co-occurrence mechanisms is developed among predatory animals along a pollution gradient, where shared resources become more limited in more contaminated areas and the energy budget for detoxification is much higher. Community disassembly by heavy metal pollution may occur when the presence of toxic elements shifts patterns of species co-occurrence from structured to random. On the other hand, limited resources on a pollution gradient should lead to higher competition between dominant species. Disassembly may entail the loss of existing co-evolved interactions among species, which has ramifications for community dynamics and the quality of the functioning of polluted ecosystems. We expect an assemblage dominated by competitive species interactions to exhibit a significant segregation of taxa, whereas one dominated by mutualistic or syntrophic interactions would exhibit an aggregation of taxa. Responses of Carabidae co-occurrence patterns and changes in body size measures to heavy metal concentrations were investigated in a zinc contamination gradient in a Scots pine forest in the vicinity of Olkusz (southern Poland), at 12 study sites. The zinc concentration in the humus layer varied between 108 mg kg-1 dw to 6150 mg kg-1 dw. We used the C-score index, between all possible species pairs in a matrix. The ground beetle assemblages from the reference sites showed a significant segregation pattern. Community disassembly occurred only among assemblages in heavily polluted sites. The average value of skewness and kurtosis were significantly higher in the highly contaminated sites, indicating the greater proportion of small-bodied species in contaminated areas. The Gini coefficient was highest in the low contaminated sites, indicating the body-size inequality of carabid assemblages was greatest in the uncontaminated areas. Our data suggest that increased pollution contributes to the extinction of sensitive forest specialists with large body size and higher competitive abilities, leading to replacement by less sensitive generalists, with smaller body size and that the co-occurrence of species on heavily polluted sites is a result of unstable interactions between species in communities

    Assemblages of carabid beetles (Col. Carabidae) and ground-dwelling spiders (Araneae) in natural and artificial regeneration of pine forests

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    Carabid beetles and spiders are at the top of the hierarchy of general invertebrate predators, which can help to reduce the abundance of harmful forest pests. They are also frequently used as environmental indicators. In this paper we analyzed the abundance, species richness and changes in carabid beetle and spider assemblages in three treatments of pine forest regeneration – natural, natural with soil prepared by ploughing and artificial with seedlings planted in ploughed soil. The most beneficial forest regeneration treatment variant of forest regeneration for carabid beetles and spiders was the natural regeneration of pine stands without any preceding soil preparation. Both taxa responded strongly to soil ploughing. We also noted the replacement of forest species by less sensitive open area species. In carabid assemblages, large changes in the trophic structure were observed, as predatory species were replaced by hemizoophages in the ploughed treatments

    Fluctuations in methane and carbon dioxide concentrations in the nearsurface zone and their genetic characterization in abandoned and active coal mines in the SW part of the Upper Silesian Coal Basin, Poland

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    The objective of this paper is to determine the origin and variability of methane and carbon dioxide concentrations in the near-surface zone and of coalbed methane in the SW part of the Chwałowice Trough and adjacent areas of the Main Syncline of the Upper Silesian Coal Basin (USCB). For this purpose soil-gas samples were taken at 202 measuring points, arranged along 5 profiles located in the mining area of the abandoned 1 Maja mine and directly adjacent areas as well as in the vicinity of four abandoned and remediated mining shafts. The maximum methane and carbon dioxide concentrations in the gas samples measured exceeds 22 and 9 vol%, respectively. The carbon isotope composition of methane and carbon dioxide was determined in samples in which elevated concentrations of these gases were found. Moreover, seven coalbed gas samples and bituminous coals were collected from coal seams exclusively from virgin parts of the Anna, Marcel, Jastrzębie, and Zofiówka mines. These data were supplemented with results of archival research for genetic interpretation of coalbed gases. Research reveals that typical humic low- and medium-volatile bituminous coals occur in Mississippian and Pennsylvanian coal-bearing strata in the study area. Fluctuations in methane and carbon dioxide concentration in the near-surface zone are related to the lithostratigraphy and tectonics of the area as well as to complicated methane depth distribution. Faults may play an important role in the microseepage of gases from deep to the near-surface zone. The connection of near-surface gases with subsurface gases was confirmed by similar stable carbon isotope composition in the methane recorded in the soil-gas samples and in the gas samples from the coal seams and sandstones of the Carboniferous formations. Distribution of anomalous methane concentrations recorded in soil-gas samples taken from profiles may indicate natural gas accumulations in the top zone of the Pennsylvanian coal-bearing formations. One example of this kind of accumulation is the Marklowice natural gas field, located within the mining area of the Marcel coal mine. Relatively high methane concentrations measured in soil gas in the vicinity of shafts I and III indicate that the degassing systems of closed and remediated mining shafts are not fully effective. Increases in carbon dioxide concentrations in the surface zone and frequent associated decreases in methane concentration were most often the result of microbial methane oxidation

    Synthetic development of a broadly neutralizing antibody against snake venom long-chain α-neurotoxins

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    Snakebite envenoming is a major global public health concern for which improved therapies are urgently needed. The antigenic diversity present in snake venom toxins from various species presents a considerable challenge to the development of a universal antivenom. Here, we used a synthetic human antibody library to find and develop an antibody that neutralizes long-chain three-finger α-neurotoxins produced by numerous medically relevant snakes. Our antibody bound diverse toxin variants with high affinity, blocked toxin binding to the nicotinic acetylcholine receptor in vitro, and protected mice from lethal venom challenge. Structural analysis of the antibody-toxin complex revealed a binding mode that mimics the receptor-toxin interaction. The overall workflow presented is generalizable for the development of antibodies that target conserved epitopes among antigenically diverse targets, and it offers a promising framework for the creation of a monoclonal antibody–based universal antivenom to treat snakebite envenoming

    Trakty koryt rzecznych w warstwach zabrskich (namur B) na podstawie analizy miąższości w rejonie siodła głównego i niecki bytomsko-dąbrowskiej Górnośląskiego Zagłębia Węglowego, Polska

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    The studied area of ca. 500 km2 lies within the Main Anticline and the Bytom-Dąbrowa Trough of the Upper Silesia Coal Basin. During the deposition of the fluvial Zabrze Beds, this area was subject to differential subsidence which resulted in gradual eastward thinning of this unit from ca. 250 m near Zabrze to ca. 4 m near Sosnowiec. Maps of net sandstone and coal contents in two stratigraphical intervals selected within the Zabrze Beds point to the presence of four channel tracts. The main tract is parallel to the NE-SW trending axis of maximum subsidence, and the other three are perpendicular to it. During deposition of the Zabrze Beds the main, NE-SW trending channel tract has shifted westward

    Sedimentology of the Early Jurassic terrestrial Steierdorf Formation in Anina, Colonia Cehă Quarry, South Carpathians, Romania

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    Authorship issues are clarified, new photographic documentation is provided and emended systematic descriptions are presented for the oldest Cambrian trilobite taxa from the Holy Cross Mountains (Poland). Biostratigraphic analysis of the fauna allows correlation with the traditional Holmia kjerulfi-group Zone of Scandinavia, the Callavia Zone of Britain and Newfoundland, the lower and middle part of the Sectigena Zone of Morocco and the Marianian Stage of Spain. The trilobites display a strong biogeographic signal linked with West Gondwana and Avalonia and a suggestion is made that the TESZ margin of Baltica with the Malopolska Massif was liable to currents from those areas that distributed planktonic trilobite larvae

    An Early Jurassic braided river system from Mehadia, South Carpathians, Romania

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    The Lower Jurassic (Hettangian–Sinemurian) continental deposits of the Mehadia area (Caraş–Severin County) belong to the Presacina Basin, Upper Danubian Units of the South Carpathians, Romania. This un-named succession is exposed along large areas within the Greaţca Quarry where deposits of a complex braided river system can be seen. Nine clastic facies are identified within the Mehadia section and grouped into two facies associations reflecting two main sub-environments. (A) a fine-grained association, up to 6.5 m thick, composed of greyish black and dark grey massive and horizontally laminated mudstones interbedded with fine- to medium-grained sandstones showing ripple lamination, tabular low-angle large-scale cross-bedding and in some places massive sandstones. Within this association coarsening and fining-upward sequences are visible, while subordinate pensymmetrical-like sequences were observed. The sediments of the fine-grained association are interpreted as having been deposited along an alluvial plain from flood waters. The sandstone interbeds are interpreted as crevasse channel-fills and the thinner sandstone bodies as proximal crevasse splays. (B) a coarse-grained facies association represented by sandstones and conglomerates, both clast- and matrix-supported, from granule to pebble clast sizes. Almost all basal members of this association are underlain by erosional surfaces, while internal erosional surfaces occur at some levels. The coarse-grained facies association is interpreted as having been deposited within active river channels of a sandy braided river system. The occurrence of numerous erosional surfaces, the recurrence of the facies within this association (channel bodies), as well as the abundant mudstone and sandstone intraclasts all point to frequent conditions of erosion (including redeposition) of previously deposited sediments. The relatively low fine-grained sediment content (<25%) can be explained by two factors: (1) a creation rate for accommodation space was not enough for the accumulation of a large amount of overbank deposits; (2) a lack of larger quantities of fine-grained material being transported in the river system. Both factors may have operated independently or interacted

    Accumulation of selected heavy metals in willow shoots (Salix viminalis L.) cultivated in the neighbourhood of a coal ash and slag landfill

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    The aim of the study was to evaluate the contents of Cd, Pb, Zn and Cu in shoots of willow (Salix viminalis L.) cultivated in the vicinity of a coal ash and slag landfill. The landfill is surrounded by arable lands and meadows. There are two major negative influences of the landfill - dusting and flooding. The result of these interactions is the systematic reduction of agricultural value of the land. A field with an area of 9600 m2 were chosen. The land is located east to the landfill. A total of 40 samples of biomass was collected. The contents of analysed elements were determined by FAAS using a Unicam Solaar M6 spectrometer. Distance from the landfill affects the contents of Cd, Pb, Zn and Cu in the tested willow shoots. However, there is no single concentration pattern for all the investigated metals. An increase in willow cultivation on the described area can bring a good environmental effect and become an example of proper management of the ash and slag landfill neighbourhood

    Cadmium and lead levels in selected goat and sheep tissues from areas under different antropogenic pressure

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    The aim of the study was to compare the levels of cadmium and lead in livers, kidneys and wool / hair / of sheep and goats reared in the vicinity of the steelworks in Nowa Huta in Kraków and in the control field, Rożniatów, in which there was no emitters of heavy metals. Samples were collected post mortem from one-year old animals of one breed (within a species) and one sex, who had lived from birth in the studied areas. Both species were fed with the same fodder and have remained in the same places. Wet mineralization was applied (mixture of nitric acid (V) and chloric (VII) (3: 1)) metal determination was done by a FASA method. The levels of the metals depend on the species, on the test areas and on the collected part of the animal. Tissues from sheep contained more cadmium and lead than the tissue of goats. The highest cadmium content was found in the kidney, lower in the liver, the lowest in the hair / wool of tested animals. Goat kidneys from both areas of research and sheep kidneys from Rożniatów meet consumer standards for cadmium. However, 20% of sheep kidneys sampled from Nowa Huta district exceeded the standards for cadmium. The lead content of both species exceeded the limit in all of the kidneys and livers from Nowa Huta district. In Rożniatów the standards were not fulfilled for all kidneys and livers of goats, and all kidneys and 70% of the livers of sheep
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