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61.
Environmental Science and Pollution Research - The energy sector of Argentina is predominantly reliant on fossil fuels. Consequently, such fossil fuel dependency within the nation’s power...  相似文献   
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Beach waste and litter composition and evolution on popular urban (located in the main nucleus of the municipality) and urbanized (located in residential areas outside the main nucleus) beaches of the Costa Brava (Catalan coast) were assessed during the bathing season. Waste and litter production (amount and composition) were affected by urbanization and varied during the summer. Urban beaches had higher densities of waste deposition and lower percentages of organic, domestic and other miscellaneous waste than urbanized beaches. Litter characteristics were also influenced by type of beach, and varied during the season as a consequence of beach use and cleaning practices, but not environmental factors. Urbanized beaches obtained higher scores for aesthetic quality of sand than urban beaches, and small-sized litter tended to accumulate during the season in the beach of Lloret Centre. The most important problems are management of recyclable materials, litter left by users on the sand, and separation of sand from litter. In addition, current efficiency of mechanical cleaning is low, especially in the withdrawal of cigarette butts. These analyses highlight problems that should be addressed in future management of area beaches.  相似文献   
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The genotoxicity associated with air pollution in the city of Canoas, Rio Grande do Sul (Brazil), was assessed in November (spring) and January (summer). We applied the somatic mutation and recombination test (SMART) in Drosophila melanogaster in its standard version with normal bioactivation (ST) and in its variant with increased cytochrome P450-dependent biotransformation capacity (HB). The data indicated the genotoxicity of TSP and PM10 collected in November, in both ST and HB crosses. The genotoxic activity of the PM10 material in the spring sample was exclusively associated with the induction of mitotic recombination, whereas the TSP genetic toxicity was due to both recombinational as well as point and/or chromosomal mutation events. Considering PM10 collected in January, a positive response--100% (17.10 m3/ml) concentration--was observed in the HB cross, which was not detected in the ST cross.  相似文献   
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Two heavy metal contaminated calcareous soils from the Mediterranean region of Spain were studied. One soil, from the province of Murcia, was characterised by very high total levels of Pb (1572 mg kg(-1)) and Zn (2602 mg kg(-1)), whilst the second, from Valencia, had elevated concentrations of Cu (72 mg kg(-1)) and Pb (190 mg kg(-1)). The effects of two contrasting organic amendments (fresh manure and mature compost) and the chelate ethylenediaminetetraacetic acid (EDTA) on soil fractionation of Cu, Fe, Mn, Pb and Zn, their uptake by plants and plant growth were determined. For Murcia soil, Brassica juncea (L.) Czern. was grown first, followed by radish (Raphanus sativus L.). For Valencia soil, Beta maritima L. was followed by radish. Bioavailability of metals was expressed in terms of concentrations extractable with 0.1 M CaCl2 or diethylenetriaminepentaacetic acid (DTPA). In the Murcia soil, heavy metal bioavailability was decreased more greatly by manure than by the highly-humified compost. EDTA (2 mmol kg(-1) soil) had only a limited effect on metal uptake by plants. The metal-solubilising effect of EDTA was shorter-lived in the less contaminated, more highly calcareous Valencia soil. When correlation coefficients were calculated for plant tissue and bioavailable metals, the clearest relationships were for Beta maritima and radish.  相似文献   
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Regional Environmental Change - Landscapes are changing rapidly in regions where rural people live adjacent to protected parks and reserves. This is the case in highland East Africa, where many...  相似文献   
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Environment, Development and Sustainability - Current trends such as imminent overpopulation and the take-make-waste economic model are largely responsible for the planet’s dire situation....  相似文献   
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The PM(2.5) concentration and its elemental composition were measured in the Cincinnati metropolitan area, which is characterized by intense highway traffic. The spatial and temporal variations were investigated for various chemical elements that contributed to the PM(2.5) fraction during a 1-year-long measurement campaign (December 2001-November 2002). The ambient aerosol monitoring was performed in 11 locations around the city during nine measurement cycles. During each cycle, four Harvard-type impactors were operating in parallel in specific locations to explore various factors affecting the PM(2.5) elemental concentrations. The sampling was performed during business days, thus assuring traffic uniformity. The 24-h PM(2.5) samples were collected on Teflon and quartz filters. Teflon filters were analyzed by X-ray fluorescence (XRF) analysis while quartz filters were analyzed by thermal-optical transmittance (TOT) analysis. In addition to PM(2.5) measurements, particle size-selective sampling was performed in two cycles using micro-orifice uniform deposit impactor; the collected fractionated deposits were analyzed by XRF. It was found that PM(2.5) concentration ranged from 6.70 to 48.3 mug m(-3) and had low spatial variation (median coefficient of variation, CV=11.3%). The elemental concentrations demonstrated high spatial variation, with the median CV ranged from 38.2% for Fe to 68.7% for Ni. For traffic-related trace metals, the highest concentration was detected in the city center site, which was close to a major highway. The particle size selective measurement revealed that mass concentration of the trace metals, such as Zn, Pb, Ni, as well as that of sulfur reach their peak values in the particle size range of 0.32-1.0 mum. Meteorological parameters and traffic intensity were not found to have a significant influence on the PM(2.5) elemental concentrations.  相似文献   
70.
A sequencing batch reactor was used to study the possibility of harvesting polyhydroxyalkanoate (PHA) from enhanced biological phosphorus removal (EBPR) processes without compromising treatment quality. Because, in EBPR, the highest PHA concentrations are observed after exposure of the sludge to anaerobic conditions, PHA accumulation was evaluated with collection of waste activated sludge (WAS) at the end of the anaerobic stage, in addition to the traditional removal after the aerobic stage. The system achieved good phosphorus removal, regardless of the point of WAS collection. When sludge was harvested at the end of the anaerobic stage, the PHA content of the sludge ranged from 7 to 16 mg PHA/100 mg mixed liquor volatile suspended solids. Although this level of PHA production is below levels obtained with pure cultures, the demonstrated ability to harvest PHA, while simultaneously satisfying phosphorus removal in an EBPR process, is a key initial step towards of the use of wastewater treatment plants for PHA production.  相似文献   
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