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1.
Mitigation of eutrophication, intensified by excessive nutrient load discharge in wastewaters regulated by restrictive legal requirements, remains one of today’s most important global problems. Despite implementation of the Water Framework Directive, the Urban Wastewater Directive and the HELCOM recommendations, the actual condition of surface water is still not satisfactory. In response to the above, the study presents an alternative approach for surface water protection against eutrophication based on the selection of appropriate nutrient removal technologies. An activated sludge model simulation was used to enable the identification of environmentally justified nutrient removal systems with lowest eutrophication potential of treated wastewater conditioned by bioavailable nutrient forms content. Based on the outcome of the study, the 3-stage Bardenpho system was identified as the most efficient for bioavailable phosphorus removal, while the Johannesburg system proved to have the highest efficiency for bioavailable nitrogen removal. The proposed eutrophication mitigation approach underlines the need for a reconsideration of current legal regulations which ignore nutrient bioavailability and key eutrophication limiting factors. 相似文献
2.
Zbigniew Kwieciński Zuzanna M. Rosin Łukasz Dylewski Piotr Skórka 《Die Naturwissenschaften》2017,104(5-6):39
Sex differences in the foraging ecology of monomorphic species are poorly understood, due to problems with gender identification in field studies. In the current study, we used experimental conditions to investigate the food preferences of the white stork Ciconia ciconia, an opportunistic species in terms of food, but characterised by a low level of sexual dimorphism. During a 10-day experiment, 29 individuals (20 females and 9 males) were studied by means of a ‘cafeteria test’ in which the storks’ diet consisted of mammals, birds, fish, amphibians, insects and earthworms. The storks preferred food characterised by high calorific and protein values such as mammals, birds and fish. Sexes differed strongly in their preferences; males preferred mammals, whereas females preferred birds. Moreover, females consumed insects and earthworms less often than males. Interestingly, males spent significantly less time foraging than females. We have demonstrated that the white stork exhibits clear sexual differences in food preferences which are mostly attributable to differences in parental duties, physiology and anatomy. 相似文献
3.
George R. Hendrey Keith F. Lewin Zbigniew Kolber Lance S. Evans 《Journal of the Air & Waste Management Association (1995)》2013,63(10):1324-1327
A prototype Free-Air Controlled Enrichment (FACE) system was developed at Brookhaven National "Laboratory (BNL) for the experimental control of gas concentrations in an open field, without any form of enclosure. This FACE system consists of a toroidal plenum chamber, 15 m in diameter, with a series of 32 vertical vent pipes from which the release of a test gas can be controlled. Data on gas concentration at the center of the array and wind velocity are fed to a microprocessor where a proportional, integrative, differential (PID) algorithm is used to regulate a mass-flow controller. Data on wind direction are used to control the opening and closing of the vertical vent pipes to maintain an upwind release. In 72 hours of continuous operation during which wind velocity varied between 0.3 to 8 m sec-1, the FACE prototype maintained 1 -min averaged concentrations within twenty percent of the 40 ppb set point 94 percent of the time. 相似文献
4.
Zygmunt Usydus Joanna Szlinder-Richert Lucyna Polak-Juszczak Magorzata Malesa-Ciewierz Zbigniew Dobrzaski 《Chemosphere》2009,74(11):1495-1501
The results of tests for the purification of fish oils with activated carbon for industrial use are presented. The optimum parameters for the process of purification (granulation of the activated carbon, its dosage, the oil temperature, and the duration of mixing the oil with activated carbon) were previously established for the laboratory scale. The optimization of the process consisted of selecting purification parameters that would allow for maximum reduction of the toxic polychlorinated dibenzo-para-dioxins and polychlorinated dibenzofurans (PCDD/Fs) content, while retaining the favorable high fatty acid content [C20:5 n−3, eicosapentaenoic acid (EPA) and C22:6 n−3, docosahexaenoic acid (DHA)]. The use of that optimum parameters in industrial conditions confirmed the satisfactory results obtained in laboratory tests. Five types of oil derived from various Baltic fish were purified. Reduction in the PCDD/Fs content was 77.0–93.6% on average, whereas in the dioxin-like polychlorinated biphenyls (dl-PCBs)—it was 42.7–50.5% on average, with insignificant changes in the total amount of EPA and DHA content. Furthermore, a significant reduction in the content of arsenic was noted (by about 62% on average), with insignificant changes in the content of organochlorine pesticides (OCPs), and marker polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), cadmium, lead, and mercury.Purification provided fish oil having standardized parameters that allow for its use as feed additives, whilst retaining its favorable fatty acid content. 相似文献
5.
Bytnerowicz A Badea O Barbu I Fleischer P Fraczek W Gancz V Godzik B Grodzińska K Grodzki W Karnosky D Koren M Krywult M Krzan Z Longauer R Mankovska B Manning WJ McManus M Musselman RC Novotny J Popescu F Postelnicu D Prus-Głowacki W Skawiński P Skiba S Szaro R Tamas S Vasile C 《Environment international》2003,29(2-3):367-376
An international cooperative project on distribution of ozone in the Carpathian Mountains, Central Europe was conducted from 1997 to 1999. Results of that project indicated that in large parts of the Carpathian Mountains, concentrations of ozone were elevated and potentially phytotoxic to forest vegetation. That study led to the establishment of new long-term studies on ecological changes in forests and other ecosystems caused by air pollution in the Retezat Mountains, Southern Carpathians, Romania and in the Tatra Mountains, Western Carpathians on the Polish-Slovak border. Both of these important mountain ranges have the status of national parks and are Man & the Biosphere Reserves. In the Retezat Mountains, the primary research objective was to evaluate how air pollution may affect forest health and biodiversity. The main research objective in the Tatra Mountains was to evaluate responses of natural and managed Norway spruce forests to air pollution and other stresses. Ambient concentrations of ozone (O(3)), sulfur dioxide (SO(2)), nitrogen oxides (NO(x)) as well as forest health and biodiversity changes were monitored on densely distributed research sites. Initial monitoring of pollutants indicated low levels of O(3), SO(2), and NO(x) in the Retezat Mountains, while elevated levels of O(3) and high deposition of atmospheric sulfur (S) and nitrogen (N) have characterized the Tatra Mountains. In the Retezat Mountains, air pollution seems to have little effect on forest health; however, there was concern that over a long time, even low levels of pollution may affect biodiversity of this important ecosystem. In contrast, severe decline of Norway spruce has been observed in the Tatra Mountains. Although bark beetle seems to be the immediate cause of that decline, long-term elevated levels of atmospheric N and S depositions and elevated O(3) could predispose trees to insect attacks and other stresses. European and US scientists studied pollution deposition, soil and plant chemistry, O(3)-sensitive plant species, forest insects, and genetic changes in the Retezat and Tatra Mountains. Results of these investigations are presented in a GIS format to allow for a better understanding of the changes and the recommendations for effective management in these two areas. 相似文献
6.
Compliance and Emissions Trading under the Kyoto Protocol: Rules for Uncertain Inventories 总被引:1,自引:0,他引:1
Zbigniew Nahorski Joanna Horabik Matthias Jonas 《Water, Air, & Soil Pollution: Focus》2007,7(4-5):539-558
A solution is proposed for proving compliance with emission targets and for emissions trading in the event of uncertainties
in reported emission inventories. The solution is based on the undershooting concept, from which the mathematical conditions
for both proving compliance with a risk α and calculating effective emissions for trading are derived. Based on the reported emission units, the number of permits
granted is reduced in proportion to the uncertainty in the inventory. A country whose inventory has higher uncertainty is
thereby allotted fewer permits than a country with the same inventory but smaller uncertainty. 相似文献
7.
The investigations were made to determine the total contents of Fe, Mn, Zn, Cu, Pb, Cd, Ni and Cr in the roadside soils and rocks of the Sierra Nevada Mountains in Spain. There were differences in both the age and lithology of the bed-rock in the study area. The surface soil layer is primarily enriched with lead in relation to the bed-rock, but zinc, manganese, and cadmium also occur.Lead, zinc and cadmium concentrations show a decrease with increasing distance from the road, whereas the levels of iron, manganese, copper, nickel and chromium do not show such a variation. The change in lead and zinc concentrations with increasing distance from the road is related to the topography of the area immediately adjacent to the road. On the descending slopes the concentrations of these metals remain unchanged or increase with the increasing distance from the road, whereas on the ascending slopes they show a clear decrease. 相似文献
8.
Mart-Jan Schelhaas Geerten Hengeveld Marco Moriondo Gert Jan Reinds Zbigniew W. Kundzewicz Herbert ter Maat Marco Bindi 《Mitigation and Adaptation Strategies for Global Change》2010,15(7):681-701
Risks can generally be described as the combination of hazard, exposure and vulnerability. Using this framework, we evaluated
the historical and future development of risk of fire and wind damage in European forestry at the national level. Fire risk
is expected to increase, mainly as a consequence of an increase in fire hazard, defined as the Fire Weather Index in summer.
Exposure, defined as forest area, is expected to increase slightly as a consequence of active afforestation and abandonment
of marginal agricultural areas. Adaptation options to fire risk should therefore aim to decrease the vulnerability, where
a change in tree species from conifers to broadleaves had most effect. Risk for wind damage in forests is expected to increase
mainly as a consequence of increase in exposure (total growing stock) and vulnerability (defined by age class and tree species
distribution). Projections of future wind climate indicate an increase in hazard (storminess) mainly over Western Europe.
Adaptation options should aim to limit the increase in exposure and vulnerability. Only an increase in harvest level can stop
the current build-up of growing stock, while at the same time it will lower vulnerability through the reduction of the share
of old and vulnerable stands. Changing species from conifers to broadleaves helps to reduce vulnerability as well. Lowering
vulnerability by decreasing the rotation length is only effective in combination with a high demand for wood. Due to data
limitations, no forecast of future fire area or damaged timber amount by storms was possible. 相似文献
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10.
Krystyna A. Skibniewska Janusz Guziur Zbigniew Marzec Stanisław Zaręba Mirosław Grzybowski Józef Szarek 《毒物与环境化学》2013,95(4):773-778
Excessive intake of nickel (Ni) is known to produce adverse health effects in humans, including carcinogenicity and allergenicity. The main route of exposure for humans is diet, including fish. There is, however, little information concerning Ni content in freshwater fish in Poland. The aim of the study was to determine the concentrations of Ni in meat tissues of three fish species from north eastern Poland and assess toxic potential to healthy and susceptible sub-groups of individuals. The settings for the study lakes span a range of anthropogenic influence from protected areas to a basin with a town and several villages and another one influenced by a pesticide tomb leakage. Fish were netted and kept frozen until analysis. After defrosting, the fish were filleted and minced. The ashed samples were dissolved in nitric acid and analyzed for Ni by flame atomic absorption spectrometry. Roach meat contained 6.6–23 µg kg?1 Ni, bream 9.5–178 µg kg?1, and carp 16.5–139 µg kg?1. These concentrations are low, indicating that the fish were not excessively contaminated with the metal. Consuming a 250 g portion of fish would result in an average nickel intake of 4 µg for roach, <10 µg for bream, and <20 µg for carp. These values represent only 0.4–2% of the maximum level that is likely to pose a risk of adverse effects as established in the USA. Consumption of fish from the study region need not necessarily pose a health threat. 相似文献