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101.
A considerable area of soils with low abundance of plant-available phosphorus and relatively low consumption of phosphorus fertilisers recorded in Poland over the last 20–25 years suggests that the dispersion of phosphates from arable soils in Poland can be low. The literature, however, provides reports on a considerable share of Polish agriculture in phosphorus pollution of Baltic Sea waters. The literature provides no data concerning phosphorus sorption parameters of arable soils in Poland. Due to this, the study involved the analysis of sorption properties: 1-point phosphorus sorption index (PSI) and degree of phosphorus saturation, based on molar ratio P, Al, and Fe determined by the Mehlich-3 method (DPS-1M3?=?P / (Al?+?Fe) and DPS-2M3?=?P / Al), 59 soils representing the main types of texture of soils in Poland, characterised by variable content of plant-available phosphorus by Egner-Riehm DL, organic carbon, and soil pH. The obtained results suggest that the soil texture has a lower effect on sorption properties (PSI) than the degree of acidification. Sorption parameters of soils increased with soil acidification as a result of an increase in the content of Al and Fe extracted by the Mehlich-3 extract in strongly acidified soils. An important finding of our study was evidencing that within the same class of abundance in plant-available phosphorus, the soils varied in the degree of phosphorus saturation and content of active phosphorus. This suggests the possibility of losses of phosphorus even from soils with low abundance of the component provided they are characterised by a high value of parameters DPS-1M3 and DPS-2M3.  相似文献   
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Bioaccumulation and toxicity of copper was evaluated on Potamogeton pusillus L. The effect of copper (5–100 μg L?1) applied for several days was assessed by measuring changes in the chlorophyll's, phaeophytin's, malondialdehyde, electrical conductivity, glutathione peroxidase (GPX), glutathione reductase (GR) and guaiacol peroxidase (POD) activities. Plants accumulated copper with a maximum of 162 μg g?1 dw after 7-days exposure at 100 μg L?1, however most of the metal was accumulated after 1-day exposure. The toxic effect caused by Cu was evident by the reduction of photosynthetic pigments, increase of malondialdehyde and electrical conductivity. P. pusillus shows Cu-induced oxidative stress by modulating antioxidant enzymes like GPX, GR and POD. Antioxidant enzymes activity increased significantly after exposure to 40 μg L?1 during 24 h, followed by a drop at longer times. Thus, P. pusillus is proposed as a good biomonitor for the assessment of metal pollution in aquatic ecosystems.  相似文献   
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A holistic assessment procedure has been used in this study for comparing conventional activated sludge (CAS) and membrane bioreactor (MBR) processes for the treatment of municipal wastewater. Technical, social, administrative, economic and environmental impacts have been evaluated based on 1 year of operational data from three full-scale lines (one MBR and two CAS) working in parallel in a large municipal treatment plant. The comparative assessment evidences a slight advantage of the conventional process in the studied case, essentially due to lower costs, complexity and energy consumption. On the other hand, the MBR technology has a better social acceptance and similar overall environmental footprint. Although these results are influenced by site-specific parameters and cannot be generalized, the assessment procedure allowed identifying the most important factors affecting the final scores for each technology and the main differences between the compared technologies. Local conditions can affect the relative importance of the assessed impacts, and the use of weighting factors is proposed for better tailoring the comparative assessment to the local needs and circumstances. A sensitivity analysis on the weighted final scores demonstrated how local factors are very important and must be carefully evaluated in the decision making process.  相似文献   
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Complex interaction between anthropogenic activities, air quality and human health in urban areas, such as in Cracow sustains the need for the development of an interdisciplinary and integrated risk-assessment methodology. In such purpose, we propose a pilot study performed on asthmatics and based on a combined use of a biomarker, such as metallothionein 2A (MT-2A) in the characterization of human exposure to one or a mixture of pollutants and of Geographical Information Systems (G.I.S.) which integrates climatic and urban anthropogenic parameters in the assessment of spatio-temporal dispersion of air pollutants. Considering global incidence of air pollution on asthma and on peripheral blood lymphocytes MT-2A expression should provide a complementary information on biological risks linked to urban anthropogenic activities. Such study would help for the establishment of a sustainable development in urban areas that can maintain the integrity of air quality and preserve human health.  相似文献   
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Propylene and 1,2-butylene carbonates enable very effective extraction of Methylene Blue. The use of a more hydrophobic 1,2-butylene carbonate is preferred for practical application. Separation is enhanced by addition of an electrolyte (NaCl). Partition coefficients for solutions containing Methylene Blue and 1M NaCl are at least a hundred times higher than for Direct Yellow solutions. The recovery of Methylene Blue with propylene and 1,2-butylene carbonates is significantly better, compared with the cloud point technique. Cloud point technique yields to almost 100% only in the case of low concentrations of Methylene Blue in the feed (0.5mg dm(-3)). For higher initial concentrations (0.01-0.25 g dm(-3)) of Methylene Blue, this method of recovery provides low extraction percentages (10-40%). Alkylene carbonates are not appropriate extractants for recovery of very hydrophilic Direct Yellow.  相似文献   
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Fifteen species of wild mushrooms and underlying soil samples collected in a virgin landscape of Augustowska Forest in northeastern Poland in 1997-98 were analyzed for total mercury to evaluate the status of contamination and usefulness of higher mushrooms as possible bioindicators of mercury pollution. Among the 15 species analyzed, Pinewood King Bolete, Scaly Tooth and King Bolete showed relatively high bioconcentration factors (BCF: dry-weight normalized concentrations of mercury in mushrooms relative to concentrations in soil) for mercury, which varied between 69 and 110. These three species were also characterized by great concentrations of total mercury in caps (between 2,000 +/- 800 and 2,300 +/- 1,100 ng g-1 dry wt) and stalks (between 850 +/- 390 and 1,000 +/- 500 ng g-1 dry wt.). Species such as Red-hot Milk Cap, Poison Pax and Common Chantherelle had mercury BCFs of less than 1, while Gipsy Bolete, Orange Birch Bolete, Brown Scaber Stalk, Variegated Bolete, Sandy Knight-cap and Yellow-cracking Bolete were weak or moderate mercury accumulators with BCFs between 1 and 40. Concentrations of mercury in mushrooms were greater than the tolerance limits suggested for mercury in plant foods.  相似文献   
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