10 results on '"Niedzielski, Przemysław"'
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2. The late Holocene decline of Trapa natansL. in Northern Poland in the light of new palaeobotanical and geochemical data
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Lewandowska, Agnieszka, Niedzielski, Przemysław, and Gałka, Mariusz
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Trapa natans(water chestnut) is an aquatic, thermophilic plant whose decline has been observed in many localities in central Europe during the last decades. In this paper, we present a description of two new T. natanssubfossil sites located outside its present northern distribution in Poland. High-resolution analysis of plant macrofossils supported by geochemical analysis were undertaken to reconstruct the palaeoecological habitat and examine the cause of the late Holocene decline of T. natansthat took place ca. 4000 calibrated years before AD 1950 (cal. yr BP) in a paleolake, presently the Bagno Kusowo bog. Its disappearance was a consequence of terrestrialisation and the development of peatland. In paleolake sediments covered by the peat layer in the Mechacz Wielki bog, T. natansmacrofossils were found from before ca. 3300 cal. yr BP. The decline of T. natanscould have resulted from the changes and development of other plant communities where the dominant role was played by Stratiotes aloidesand Nymphaeasp. In our study sites, T. natansoccurred together with Potamogeton crispus, Potamogeton obtusifolius, Nymphaea alba, and Nupharsp. in eutrophic water dominated by Ca2+, Fe3+, and Al3+ions. Our palaeobotanical and geochemical results align with the contemporary conditions of T. natanshabitat.
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- 2019
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3. Hydrochemical Diversity of a Large Alluvial Aquifer in an Arid Zone (Draa River, S Morocco)
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Szczucińska, Anna, Dłużewski, Maciej, Kozłowski, Rafał, and Niedzielski, Przemysław
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In arid areas, with rivers functioning episodically, alluvial resources are the main source of water. Considering the intensified regulation of discharge in montane catchments, supplying the intermittent rivers, in the nearest future alluvial aquifers will gain key importance for the functioning of people in arid zones. The research aimed to investigate the diversified chemistry of alluvial waters typical of large intermittent river valleys in hot arid zones as well as to analyse processes determining the water chemistry and affecting its diversity. The detailed study, carried out in October 2015, covered the Draa river valley (1100 km total length) in the region of the Mhamid Oasis. The examined water was sampled from all wells found in the study area. Concentrations of the main cations: Ca2+, Mg2+, K+, Na+, NH4+, and Li+, anions: Cl−, SO42−, HCO3−, and NO3−, as well as trace elements: Al, As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, and Zn, were identified. Results were analysed with statistical, hydrochemical, and geochemical modelling methods. Alluvial waters of the eastern and western part of the oasis differed in concentrations of numerous components, what resulted from the regulation of irrigation. Specific electrical conductivity showed a 3.5-fold increase, from 3800 to 13800 μS/cm, consistent with the direction of water flow in the oasis, from east to west. Even a greater rise was observed for ions: Cl−(6x), Na+(5.5x), Mg2+(5.0x), Ca2+, and SO42−(3.5x). Such a composition indicated multiionic hydrochemical type of waters dominated by Na+and Cl−. Additionally, high Pearson correlation coefficients were recorded for Na+and Cl−(0.98) as well as Mg2+and Cl−(0.97). The saturation index suggested that the main water components originated from dissolving of minerals such as halite, anhydrite, sylvite, and gypsum. Groundwater chemistry in the Mhamid Oasis was determined mainly by geogenic processes, such as dissolving of evaporates, precipitation of carbonate minerals, and ion exchange.
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- 2019
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4. Monitoring of essential and toxic elements in multi-ingredient food supplements produced in European Union
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Poniedziałek, Barbara, Niedzielski, Przemysław, Kozak, Lidia, Rzymski, Paweł, Wachelka, Marcin, Rzymska, Izabela, Karczewski, Jacek, and Rzymski, Piotr
- Abstract
The market of food supplements (FS) in European Union (EU) is on the rise. The present study investigated the content of essential (Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Zn) and toxic elements (Cd, Cr(VI), Ni and Pb) in 168 FS produced in the EU and designed to support various health aspects (nutrition, neurological function, reproduction, weight loss, cosmetic appearance). The majority of FS did not exceed a dissolution time of 60 min in hydrochloric acid (89.8%) and phosphate buffer (85.7%). Cd and Cr(VI) were not detected in any FS, Ni and Pb were present sporadically (in 10.1 and 6.5%, respectively) at mean concentrations of 0.06 and 0.07 mg/single unit dose, respectively. All FS containing detectable Pb levels had exceeded a maximum allowance level (3.0 mg kg−1) set by the European Commission. Generally, the determined concentrations of essential elements fall greatly below recommended safety upper limits, except Fe in selected FS (mainly for pregnant women). Compared to the value declared on the product label, the majority of tested FS displayed mineral content below the accepted margin (70–130%). In general, the majority of the studied FS can be considered safe although discrepancies between declared and determined mineral content are worrisome. These findings are important in view of FS consumer safety.
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- 2018
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5. The influence of urban agglomeration on a small natural water reservoir
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Sobczyński, Tadeusz and Niedzielski, Przemysław
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The aim of the study was to determine the influence of urban agglomeration on a small, natural water reservoir which, as a result of the expansion of the city of Poznań, has become an urban lake. In the vegetation period 2015, the chemistry of its water was studied, and in September additional samples of bottom sediments, plants and fish were collected for analysis in order to determine the content of heavy metals. In terms of productivity, no significant influence of the catchment was recorded. In the 1980s the lake was defined as eutrophic, and in 1996 as α-mesotrophic and such a state continues until today. This is the result of protective activity undertaken by its new owner. The adverse influence of the urbanization of the surrounding areas was reflected by the increased content of lead in particular elements of this ecosystem, that is, in bottom sediments, plants and fish muscles.
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- 2018
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6. Sedimentary fractions of phosphorus before and after drainage of an urban water body (Maltański Reservoir, Poland)
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Rzymski, Piotr, Sobczyński, Tadeusz, Klimaszyk, Piotr, and Niedzielski, Przemysław
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Urban reservoirs can receive high loads of chemicals, including persistent contaminants and eutrophication-promoting nutrients. To maintain their economic and recreational use, implementation of various restoration methods is often required. The Maltański Reservoir (Poland, Europe), a small, shallow and dammed urban water body, undergoes complete draining every four years as part of its restoration procedure. Here, we investigated the phosphorus (P) content and its fractions just before the reservoir was drained and after it had been completely filled with water again. As demonstrated, the highest accumulation of P occurred at sites through which the main water flow is directed. Calcium-bound and residual P constituted the largest proportion of P fractions. A shift in P fractions after the reservoir was drained and sediments were left without water for at least 4 months was observed. A decrease in phytoplankton utilized NH4Cl-P, Fe-P and NaOH-P fractions was found and followed a simultaneous increase in nearly biologically inaccessible HCl-P and practically biologically inactive residual P fractions. Our study demonstrates that complete drainage of the Maltański Reservoir may additionally decrease the risk of internal P loading through shifts in its fractions.
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- 2015
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7. Cadmium and lead toxicity and bioaccumulation in Microcystis aeruginosa
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Rzymski, Piotr, Poniedzialek, Barbara, Niedzielski, Przemysław, Tabaczewski, Piotr, and Wiktorowicz, Krzysztof
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The growth of human population leads to intensification of agriculture and promotes, through eutrophication, development of cyanobacteria. One of the most widespread and bloom-forming species in freshwater is toxic Microcystis aeruginosa(M. aeruginosa). Combustion of fossil fuels and metallurgical processes are the main sources of heavy metals contamination in surface water including cadmium (Cd) and lead (Pb). The following study was conducted in order to determine the effect of 1–20 mg·L−1of Cd and Pb on photochemistry (using flow cytometry) and growth (based on chlorophyll concentration) of M. aeruginosaas well as to estimate levels of metal bioaccumulation. We have found that 1–10 mg·L−1of Cd and 1–5mg·L−1of Pb induced continuous enhancement of chlorophyll fluorescence during 24 h of incubation. No significant degradation of chlorophyll was observed in these samples. At higher concentrations of 20 mg·L−1of Cd and 10–20 mg·L−1of Pb chlorophyll level significantly decreased and its fluorescence was quenched. M. aeruginosademonstrated high capability of Cd and Pb bioaccumulation, proportionally to initial metal concentration. In samples with initial concentration of 20 mg·L−1of Cd and Pb bioaccumulation of 87.3% and 90.1% was observed, respectively. Our study demonstrates that M. aeruginosacan potentially survive in highly metals polluted environments, be a primary source of toxic metals in the food chain and consequently contribute to enhanced toxicity of heavy metals to living organisms including human.
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- 2014
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8. Metal accumulation in sediments and biota in Malta Reservoir (Poland)
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Rzymski, Piotr, Klimaszyk, Piotr, Niedzielski, Przemysław, and Poniedziałek, Barbara
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Municipal water reservoirs improve urban landscape architecture, providing water for various domestic uses. At the same time, they are under strong human impact affecting water quality and biological conditions. We investigated the level of metal accumulation (Cd, Co, Cr, Cu, Fe, Ni, Mn, Pb and Zn) in sediments as well as mussels Anodonta anatina and Unio tumidus and common reed Phragmites australis collected from 8 sampling sites at Malta Reservoir (Poznań, Poland) just before the complete drainage of the lake in November, 2012. In all investigated samples metal concentrations ranked in decreasing order: Fe>Mn>Zn>Cu>Cr>Ni>Pb>Co>Cd. Accumulation of toxic metals in roots of P. australis was higher than in soft tissues of mussels although it did not exceed phytotoxic levels. Roots of P. australis accumulated high levels of Cr (mean 9.7 μg g-1) and Ni (mean 5.7 μg g-1). U. tumidus accumulated higher concentrations of Cr (mean 1.1 μg g-1) than A. anatina indicating potential use in bioindication of this metal. The present study provides the most recent information on metal content in sediments and biota in Malta Reservoir and, further, suggests that this reservoir is capable of accumulating toxic elements from preceding water bodies (Lake Swarzędz) and surrounding residential areas.
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- 2013
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9. Speciation analysis of inorganic form of arsenic in ground water samples by hydride generation atomic absorption spectrometry with insitu trapping in graphite tube
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Niedzielski, Przemysław and Siepak, Marcin
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This paper presents the results of a study on the optimization of the determination of total arsenic and its species using the absorption atomic spectrometry method combined with hydride generation and in-situ concentration on the inner walls of the graphite tube. To ensure a maximum efficiency of the in-situ analyte concentration on the graphite tube walls, a palladium modifier subjected to preliminary thermal reduction was used. The limits of detection (3σ) were 0.019 ng/mL for total As and 0.031 ng/mL for As(III) at the preliminary analyte concentration for 60s. The optimised procedure of the analyte concentration on the inner walls of the atomiser (graphite tube) was applied for determinations of arsenic in samples of ground water. The content of arsenic in the samples studied varied from 0.21 ng/mL to 0.80 ng/mL for As(III), and from 0.19 ng/mL to 1.24 ng/mL for As(V).
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- 2005
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10. Elemental variability of prehistoric ceramics from postglacial lowlands and its implications for emerging of pottery traditions - an example from the pre-Roman Iron Age
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Jasiewicz, Jarosław, Niedzielski, Przemysław, Krueger, Michał, Hildebrandt-Radke, Iwona, and Michałowski, Andrzej
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•In post-glacial areas, study on the origin of ceramics is limited by the prevalence of the raw material.•Unsupervised analyzes, controlled by the place of origin of the pottery, revealed the complex process behind the elemental composition of ceramics.•The diversity of the elemental composition of pottery is smaller than in the raw material of clays from glacial regions.•Regardless of where the raw material is taken, the manufacturing process lead to he reduction of differences in elemental composition.
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- 2021
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