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71.
This paper presents daily, monthly and yearly variations of PAH mass concentrations measured in PM(10) particle fraction, collected at one measuring site in Zagreb air between 2001 and 2004, and seasonal differences in PAH mass concentrations in PM(10) samples collected from 21 March 2003 to 20 March 2004. Twenty-four hour samples were taken in the northern residential part of Zagreb using a low-volume (50 m(3)) sampler and glass or quartz filters. The analysis was performed using a high-performance liquid chromatograph (HPLC) and fluorescence detector with changeable excitation and emission wavelength. The annual average mass concentrations over the four-year measuring period for BaP ranged from 1.17 ng/m(3) in 2004 to 1.87 ng/m(3) in 2003 and were below the limit value (2 ng/m(3)) set by the Ordinance on Recommended and Limit Air Quality Values in Croatia. The highest concentrations of all PAHs measured in PM(10) samples collected from 21 March 2003 to 20 March 2004 were found in the winter and the lowest in the summer. Winter average of BaP was 2.94 ng/m(3) and summer average 0.12 ng/m(3). Autumn average was 2.76 ng/m(3) and was very similar to winter concentrations. Spring average of 0.58 ng/m(3) was higher than the summer average (0.12 ng/m(3)). Mass concentrations of all measured PAHs were much higher in the autumn than in the spring. Although annual averages for BaP did not exceed the limit value, autumn and winter BaP mass concentrations did, which calls for measures for reducing PAH emissions in the autumn and winter.  相似文献   
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Exploitation of certain resources within a protected area on a sustainable basis could contribute to higher living standards of rural people, particularly those in poor countries, and decrease conflicts between these populations and park authorities. This article presents data from a case study of Kopaonik National Park (NP), Serbia, which is a park with natural resources, most notably bilberries, which have always been relied on by local people. Vaccinium myrtillus traditionally has been collected for decades in Kopaonik NP and used by local people. However, little is known about the socioeconomic and ecological relations that affect the collection and use of this species. The aim of the present study was to understand how local people collect bilberries in Kopaonik NP and what their attitudes toward the park are. Household questionnaire data were used to examine how local people collect bilberries and how to improve the relations between local people and NP authorities. The survey questionnaire included 52 households from 7 local communities, and we applied a purposive sampling strategy. In addition, expert interviews were conducted, and from these data we obtained a broader understanding of the relation between local people and NP authorities. The results indicate that in Kopaonik NP, there is a conflict between pickers and NP authorities. Sustainable management should be directed toward the protection of bilberries. Education of local people is a key element in the sustainable collection and protection of natural resources.  相似文献   
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Environmental Chemistry Letters - Plastic pollution in water ecosystems is threatening the survival of wildlife. In particular, microplastics may be encapsulated into calcium carbonate, a crucial...  相似文献   
74.
The efficiency of providing a waste management system in the coastal part of Croatia consisting of four Dalmatian counties has been modelled. Two multi-criteria decision-making (MCDM) methods, PROMETHEE and GAIA, were applied to assist with the systematic analysis and evaluation of the alternatives. The analysis covered two levels; first, the potential number of waste management centres resulting from possible inter-county cooperation; and second, the relative merits of siting of waste management centres in the coastal or hinterland zone was evaluated. The problem was analysed according to several criteria; and ecological, economic, social and functional criteria sets were identified as relevant to the decision-making process. The PROMETHEE and GAIA methods were shown to be efficient tools for analysing the problem considered. Such an approach provided new insights to waste management planning at the strategic level, and gave a reason for rethinking some of the existing strategic waste management documents in Croatia.  相似文献   
75.
GOAL, SCOPE AND BACKGROUND: The objective of this paper is to determine and compare the concentrations of U and Th in soft to hard brown (lignite to sub-bituminous) coals of Serbia and Montenegro. It also presents comparison of the obtained data on U and Th concentrations with the published data on coals located in some other countries of the world. Almost the whole coal production of Serbia and Montenegro is used as feed coals for combustion in thermal power plants. METHODS: Channel samples from open pit and underground mines and core samples were collected for hard and soft brown coals. For the analysis the samples were decomposed using microwave technique. Obtained solutions containing U and Th were analyzed by inductively coupled plasma mass spectroscopy (ICP-MS) using NIST standards. RESULTS: Concentration of U from the investigated basins and the corresponding mine fields ranges within 0.60-70.10 mg/kg, 0.65-3.20 mg/kg, 0.95-6.59 mg/kg, 1.20-6.05 mg/kg, 0.80-6.66 mg/kg, 0.18-89.90 mg/kg, 0.19-4.14 mg/kg, and 0.28-3.52 mg/kg for the Kostolac, Kolubara, Krepoljin, Sjenica, Soko Banja, Bogovina East field, Senje-Resavica and Pljevlja basins, respectively. Concentration of Th ranges within 0.20-2.60 mg/kg, 0.84-6.57 mg/kg, 1.48-6.48 mg/kg, 0.12-2.71 mg/kg, 0.13-4.95 mg/kg, 0.14-3.48 mg/kg, 0.29-3.56 mg/kg, and 0.17-1.89 mg/kg for the Kostolac, Kolubara, Krepoljin, Sjenica, Soko Banja, Bogovina East field, Senje-Resavica and Pljevlja basins, respectively. DISCUSSION: Brown coal from Senje-Resavica, Kolubara, Kostolac and Pljevlja is characterized by low U concentration. Coals form the Krepoljin, Soko Banja and Sjenica basins have slightly higher U concentrations than the mentioned group. The highest concentration of U is characteristic for the coal from the Bogovina East field. Concentration of Th in coals from Serbia and Montenegro has proved to be low. Out of all investigated coal basins, only the coal from the Krepoljin and Kolubara basins has high concentration of Th. The hydrothermally altered rocks of the Timok dacite-andesite complex, representing the basement of the Bogovina basin, could be a potential source of U, especially at the bottom part of the Lower seam of the Bogovina East field. CONCLUSIONS: This study shows that brown coals in Serbia and Montenegro (soft to hard brown coals or lignite to sub-bituminous) contain low levels of U (5.30 mg/kg, average value and 2.10 mg/kg geometric mean value) and Th (1.80 mg/kg, average value and 1.12 mg/kg geometric mean value). There are some obvious differences in concentration of U and Th in coals from different basins in Serbia and Montenegro. The approximate value for U and Th release mainly from power plants was 644.33 t and 983.46 t, respectively within the period 1965-2000 for the studied mines in Serbia, and 23.76 t and 15.05 t for the Potrlica mine (Montenegro) within the period 1965-1997. RECOMMENDATIONS: The coals in Serbia and Montenegro show no identifiable unfavourable impact on the surrounding environment, due to low natural radioactive concentration of U and Th, but further investigations concerning human health should be performed. PERSPECTIVES: Preliminary research revealed that in some Serbian coals (and, particularly, parts of the coal seam) U and Th content are rather high. Such coals should be carefully studied, as well as U and Th concentrations in ash, fly ash, waste disposals, nearby soil and ground water. Further studies should include determination of the radioactivity of all these products, and estimation of possible health impact.  相似文献   
76.
An overview of environmental distribution of tritium in the Danube basin in Yugoslavia during the period 1976-1990 is presented. Temporal and regional variations of environmental tritium in the Danube along its flow (1425-847 km from the confluence) and its tributaries (the Sava, the Tisa, the Velika Morava and the Timok) at various locations, as well as in alluvial groundwaters, are given. In Belgrade, monthly values of tritium in rainfall ranged from 1.1 to 18.3 Bq litre(-1), with a maximum in the late spring and early summer months. The half-life for decline in concentration was estimated as 8.3+/-1.0 years. The total amount of tritium deposited in the first 6 months during 1976-90 was 35% larger than in the second 6 months for the same period. Seasonal variations were noticeable in rivers and groundwaters, but these were greatly attenuated and smoothed for the latter. Tritium content in the monthly composite samples from the river in the Belgrade region varied between 2.5 and 18.2 Bq litre(-1) for the Danube and from 1.5 to 16.8 Bq litre(-1) for the Sava. The yearly mean values along the Danube and its tributaries ranged from 2.4 to 15.9 Bq litre(-1) with individual measurements 1.0-30.2 Bq litre(-1). The half-lives were between 6.9+/-1.7 for the Velika Morava and 9.4+/-0.9 for the Danube. Groundwaters, particularly ones in the Ranney wells, followed changes of tritium content in the rivers with a time lag from a few days to a month. During the period of observation, tritium content decreased in alluvial waters with half-lives from 9.9+/-1.6 (Belgrade area) to 7.3+/-1.8 (the Velika Morava).  相似文献   
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