Publications by authors named "Cwanek A"

This study concerned high-resolution age reconstructions of modern organic deposits collected from peatlands distributed in Central Europe. The main focus was on Pb radioisotope as a fundamental geochronometer along with C and Pu radioisotopes used for dating verification. In addition to simple classical models such as CF/CS or CF, the new approach formulated upon the Plum method was implemented.

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Cryoconite, granule-shaped debris found on the surface of glaciers, is known for trapping substantial quantities of pollutants such as radioactive nuclides and heavy metals. This study investigates contamination levels, sources and spatial variability of natural and artificial radioisotopes in cryoconite from Mittivakkat Gletsjer in southeast Greenland by determining the activity and atomic ratios of selected radionuclides. The maximum activity concentrations of artificial radioisotopes were 1129 ± 34 Bq kg for Cs, 3.

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Glaciers are recognized as repositories for atmospheric pollutants, however, due to climate change and enhanced melting rates, they are rapidly transitioning from being repositories to secondary sources of such apollutants. Artificial radionuclides are one of the pollutants found on glaciers that efficiently accumulate onto glacier surfaces within cryoconite deposits; a dark, often biogenic sediment. This work provides information about the accumulation, distribution and sources of plutonium (Pu) isotopes in cryoconite samples from glaciers worldwide.

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Glacier mice are peculiar rolling or stationary moss balls found on the surface of some glaciers. They may harbour an ecological habitat for cold-adapted invertebrates and microorganisms, but little is known about their potential to accumulate and disseminate harmful elements and substances. In this study, we investigate the presence of fallout radionuclides (Cs, Pu, Pu, Pu, Pb) and heavy metals (Pb, As, Hg, Cd) in glacier mice and compare the results to bryophytes from adjacent glacier ecosystems.

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In some locations around the globe, the U concentrations may exceed WHO standards by 2-folds therefore, effective yet environmentally wise solutions to purify radioactive waters are of significant importance. Here, the optimized and fully controlled coal-fly-ash based Na-P1 zeolite functionalization by employing novel, biodegradable biosurfactant molecule - cocamidopropyl betaine (CAPB) is showcased. The zeolite's surface decoration renders three composites with varying amounts of introduced CAPB molecule (Na-P1 @ CAPB), with 0.

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Uranium, a key member of the actinides series, is radioactive and may cause severe environmental hazards once discharged into the water due to high toxicity. Removal of uranium via adsorption by applying tailored, functional adsorbents is at the forefront of tackling such pollution. Here, we report the optimized functionalization of the powder coal fly-ash (CFA) derived Na-P1 synthetic zeolite to the form of granules by employing the biodegradable polymer-calcium alginate (CA) and their application to remove aqueous U.

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Article Synopsis
  • Rapid temperature increases in high-latitude areas are dramatically altering wetland ecosystems, particularly in Arctic Alaska, prompting researchers to examine changes in plant communities.
  • Detailed palaeoecological analyses revealed a recent expansion of certain Sphagnum populations and dry habitat vascular plants from 2000 to 2015, linked to rising temperatures and lower water tables, while historical data indicated high water tables between 1500-1950 led to different dominant plant species.
  • The study emphasizes the significance of hydroclimatic fluctuations on Arctic peatland vegetation and the value of river valley peatlands in understanding past environmental conditions.
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The peat archives are one of the stratigraphic records revealing clearly physical, chemical and biological signals of human influence on the Earth System since the 1950s, at least. The presented study was aimed mainly to identify the level and origin of anthropogenic radionuclides such as Pu in a Pb-dated peat profile derived from the Northern Ural, Russian Federation. As stated, the vertical variability of Pu/Pu isotopic compositions reflects the nuclear weapons testing history with the maximum in the 1960s and small regional impact most likely of high-yielded tests in the 1950s as well as Chinese detonations in the 1970s.

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This work provides a novel data set on accumulations of both anthropogenic (Cs, Pu, Pu, Am) and natural (Pb, Ra, Th) radionuclides and an element (K). Sampling of soils and lake sediments was accomplished in 1999 during Tundra Northwest (TNW-99) international expedition to a remote region of the Canadian Arctic. The sediment ages and sedimentation rates were determined.

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The paper presents results of the radioecological investigation carried out in south-western Greenland shoreline. There were examined over 50 samples of lichens and mosses collected from 7 locations during two scientific expeditions conducted in the summer of 2012-2013. The levels, trends and the most likely origin were determined for following natural and artificial radionuclides: Sr, Cs, Th, U, Pu and Am.

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This research concerned radioactivity of lichens and mosses from coastal zones of the Canadian Arctic and Alaska. Over 50 samples were collected from 7 positions during two scientific expeditions in 2012 and 2013. The tundra contamination caused by anthropogenic radionuclides was relatively low, reaching mean values with SD's of: 17.

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Cryoconite granules are mixtures of mineral particles, organic substances and organisms on the surface of glaciers where they decrease the ice albedo and are responsible for formation of water-filled holes. The contaminants are effectively trapped in the cryoconite granules and stay there for many years. This study evaluates the contamination level of artificial and natural radionuclides in cryoconite holes from Adishi glacier (Georgia) and identifies the sources of contamination based on activity or mass ratios among artificial radionuclides.

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The paper summarizes results of investigation of the current state of radioactive contamination on site being under consideration for planned nuclear power plant in northern Poland. Thanks to use of sequential procedure it was possible to determine activity concentrations for radioisotopes of nine elements, both natural and artificial. Results show that observed levels of radioactive contamination are rather typical for central Europe and global fallout is dominant factor of presence of artificial radionuclides.

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