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321.
Fungi can effectively accumulate various metallic elements, metalloids and non-metals in fruiting bodies. This study provides information on the accumulation of Ag, As, Ba, Cd, Co, Cs, Cu, Cr, Li, Mn, Ni, Pb, Rb, Sr, V, Tl, U and Zn in the edible mushroom Sarcodon imbricatus (L.) P. Karst. using the technique of inductively coupled plasma – mass spectrometry with a dynamic reaction cell mode. Mushrooms were foraged from four regions in Poland. Baseline concentrations of minerals, expressed in mg kg?1 dry biomass (db), were in the composite samples of caps in the range: for Ag (0.27–0.29), As (1.0–1.9), Ba (0.31–0.45), Cd (4.5–6.3), Co (0.23–1.9), Cu (28–35), Cr (0.19–0.29), Cs (20–38), Li (0.013–0.020), Mn (5.9–8.8), Ni (0.81–1.4), Pb (0.94–1.6), Rb (490–700), Sr (0.14–0.19), Tl (0.058–0.11), U (0.002–0.002), V (0.044–0.054) and Zn (140–160). Concentration levels of Ag, As, Cd, Cs, Pb and Zn were higher in caps than in stipes of S. imbricatus, whereas for other elements the distribution between caps and stipes was nearly equal or for some differed depending on the location. Certainly, the content of toxic Cd in S. imbricatus was elevated (0.45–0.63 mg kg?1 in fresh caps) and therefore eating this mushroom could increase exposure to Cd. In addition, the content of toxic As in S. imbricatus was elevated.  相似文献   
322.
In this paper, we present a comprehensive framework for analysing formal rules regulating the involvement of various actors in protected areas decision-making over time and apply it to Poland. Based on the analysis of legal acts and policy documents, we suggest that since the democratic transition started in 1989, the governance of Polish protected areas has been increasingly multi-level and participatory. However, different designations indicate different levels of involvement by non-state actors, with Natura 2000 standing out from the traditional protected areas. Regarding governance issues, establishing and taking management decisions were characterised by the greatest changes in actors’ involvement. While participation of non-public actors is still limited mostly to information and consultation, the involvement of non-state public actors of various levels increased significantly. The paper highlights the importance of a systematic analysis of legal rules as a starting point for empirical investigation of the governance of protected areas.  相似文献   
323.
The impact of industrial heavy metal pollution on Scots pine (Pinus sylvestris L.) and black pine (Pinus nigra Arn.) populations was investigated. Sampled pine stands, which were located in Upper Silesia (southern Poland) in an area strongly polluted by heavy metals, consisted of resistant and sensitive trees. To evaluate the adaptation process, genetic structure and diversity was tested using isozyme analysis. Higher levels of Zn, Pb, Cd and Cu were detected in needles of sensitive trees compared with resistant ones. With respect to morphology, Scots pines were more distinctly impaired than black pines. Although black pines had lower heavy metal concentrations, levels in 1-year-old needles, other than Cu, significantly exceeded “reference plant” values (Markert 1994). In both species, resistant trees demonstrated a lower degree of genetic variation than metal-sensitive trees with respect to some enzyme loci (SHDH A, PGI, PGM, MDH C and DIA). This observation was corroborated in sensitive trees by the smaller number of identified alleles and alleles per locus, absence of private alleles and significant excess of homozygotes in relation to expected Hardy–Weinberg equilibrium values. Assuming that only resistant trees of both species survive under conditions of prolonged soil contamination, the observed genetic structure implies that remaining populations will be depleted of some alleles of unknown adaptive value to future selection pressures. Genetic changes induced by heavy metals suggest an important role for specific enzymes—FEST, SHDH A and B, GOT B and PGI—in the adaptation process. Our results may serve as a basis for selection and propagation of individuals appropriate for re-cultivation of areas chemically degraded by industrial activity.  相似文献   
324.
Anaerobic sludge digester supernatant characterized by 569 mg TKN L?1, high color and a COD/N ratio of 1.4 was treated in granular sequencing batch reactors (GSBRs) followed by post-denitrification (P-D) and ultrafiltration (UF) steps. The use of granular sludge allowed for the oxidation of ammonium in anaerobic digester supernatant at all investigated GSBR cycle lengths of 6, 8 and 12 h. The highest ammonium removal rate (15 mg N g?1 VSS h?1) with removal efficiency of 99% was noted at 8 h.Since the GSBR effluent was characterized by a high concentration of nitrites, slowly-degradable substances and biomass, additional purification steps were applied. In P-D stage, the microbial activity of granular biomass in the GSBR effluent was implemented. The P-D was supported by external carbon source addition and the most advantageous variant comprised dosing of half of the theoretical acetate dose for nitrite reduction in the 3-h intervals. The use of the system consisting of the GSBR with 8 h, an optimal P-D variant and a UF for the treatment of anaerobic digester supernatant allowed for the 99%, 71% and 97% reductions of TKN, COD and color, respectively.  相似文献   
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327.
The aim of this work was to assess dietary risk resulting from consumption of polycyclic aromatic hydrocarbons (PAHs) with tea infusions. To this end, levels of 28 PAHs in black, green, red and white teas available on the Polish retail market have been assessed. Profiles and correlation between concentrations of individual PAHs have been identified. A model study on transfer of PAHs from tea leaves into tea preparations has been conducted. Relatively high concentrations of 28 evaluated PAHs have been found in 58 tested samples of black, green, red and white teas sampled on the Polish retail market. Total concentration ∑28PAH ranged from 57 to 696 µg kg?1 with mean 258 µg kg?1 (dry tea leaves). The most mature tea leaves fermented to a small degree contained relatively the highest PAH levels among all four tested tea types. Relatively low PAH transfer rates into tea infusions and limited volumes of the consumed tea keep the risks associated with PAH dietary intake at a safely low level.

The worst-case scenario dietary intake values were 7.62/0.82/0.097 ng kg?1 b.w. day?1 (estimated on the basis of the maximum found concentrations 696/113/23 µg kg?1 and maximum observed transfer rates 24/16/9%) for ∑28PAH/∑PAH4/B[a]P, respectively. MOE values calculated using the above worst case estimates exceeded 700,000 and 400,000 (BMDL10 0.07 and 0.34 mg kg?1 b.w. day?1) for B[a]P and PAH4, respectively. Both B[a]P and PAH4 concentrations may be used as indicators of total PAH concentration in tea leaves; PAH4 slightly better fits low molecular weight PAHs. Several correlations between various PAHs/groups of PAHs have been identified, the strongest one (R2 = 0.92) between PAH4 and EU PAH 15+1.  相似文献   
328.
There exist many classification systems of hydrographic entities such as lakes found along the coastlines of seas and oceans. Each system has its advantages and can be used with some success in the area of protection and management. This paper aims to evaluate whether the studied lakes are only coastal lakes or rather bodies of water of a completely different hydrological and hydrochemical nature. The attempt to create a new classification system of Polish coastal lakes is related to the incompleteness of lake information in existing classifications. Thus far, the most frequently used are classifications based solely on lake basin morphogenesis or hydrochemical properties. The classifications in this paper are based not only on the magnitude of lake water salinity or hydrochemical analysis but also on isolation from the Baltic Sea and other sources of water. The key element of the new classification system for coastal bodies of water is a departure from the existing system used to classify lakes in Poland and the introduction of ion-“tracking” methods designed to identify anion and cation distributions in each body of water of interest. As a result of the work, a new classification of lakes of the southern Baltic Sea coastal zone was created. Featured objects such as permanently brackish lakes, brackish lakes that may turn into freshwater lakes from time to time, freshwater lakes that may turn into brackish lakes from time to time, freshwater lakes that experience low levels of salinity due to specific incidents, and permanently freshwater lakes. The authors have adopted 200 mg Cl? dm?3 as a maximum value of lake water salinity. There are many conditions that determine the membership of a lake to a particular group, but the most important is the isolation lakes from the Baltic Sea. Changing a condition may change the classification of a lake.  相似文献   
329.
Lanthanum-modified TiO2 photocatalysts (0.2–1.5 wt% La) were investigated in the methanol decomposition in an aqueous solution. The photocatalysts were prepared by the common sol-gel method followed by calcination. The structural (X-ray diffraction, Raman, X-ray photoelectron spectroscopy), textural (N2 physisorption), and optical properties (diffuse reflectance spectroscopy, photoelectrochemical measurements) of all synthetized nanomaterials were correlated with photocatalytic activity. Both pure TiO2 and La-doped TiO2 photocatalysts proved higher yields of hydrogen in comparison to photolysis. The photocatalyst with optimal amount of lanthanum (0.2 wt% La) showed almost two times higher amount of hydrogen produced at the same time as in the presence of pure TiO2. The photocatalytic activity increased with both increasing photocurrent response and decreasing amount of lattice and surface O species. It has been shown that both direct and indirect mechanisms of methanol photocatalytic oxidation participate in the production of hydrogen. Both direct and indirect mechanisms take part in the formation of hydrogen.  相似文献   
330.
Mussels have the ability to control biomineral production and chemical composition, producing shells with a range of functions. In addition to biological control, the environment also seems to influence the process of biomineralization; thus, shells can be used as archives of ambient water parameters during the calcium carbonate deposition. Past and present environmental conditions are recorded in the shells in the form of various proxies including Mg/Ca or Sr/Ca ratios. For such proxies to be accurate and robust, the influence of biological effects including the size of studied organism must be examined and eliminated or minimized, so that the environmental signal can be efficiently extracted. This study considers mineralogy and elemental composition of shells representing four size classes of Mytilus trossulus from the Baltic Sea. Obtained results suggest that mineralogy and chemical composition change throughout the shell development due to most likely a combination of environmental and biological factors. The content of aragonite increases with increasing shell size, while the bulk concentrations of Na, Cd, Cu, U, V, Zn and Pb were found to decrease with increasing height of the shells. Therefore, using mussels for environmental monitoring requires analysis of individuals in the same size range.  相似文献   
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