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51.
Marize Pereira Miagostovich Flávia Ramos Guimarães Carmen Baur Vieira Tulio Machado Fumian Nilson Porto da Gama Matias Victoria Jaqueline Mendes de Oliveira Anna Carolina de Oliveira Mendes Ana Maria Coimbra Gaspar José Paulo Gagliardi Leite 《Food and environmental virology》2014,6(2):110-115
The preservation of water resources is one of the goals of the designation of parks that act as natural reservoirs. In order to assess the impact of the presence of humans in an environmental preservation area bordering urban areas, the presence of four pathogenic enteric viruses [group A rotavirus (RV-A), norovirus (NoV), human adenoviruses (HAdV), and hepatitis A virus (HAV)], as well as the physico-chemical parameters, and Escherichia coli levels were assessed in riverine water samples. From June 2008 to May 2009, monthly monitoring was performed along the Engenho Novo River. RV-A, NoV, and HAdV were observed in 29 % (31/108) of the water samples, with concentrations of up to 103 genome copies/liter. The natural occurrence of infectious HAdV was demonstrated by Integrated Cell Culture-PCR (ICC-PCR). This study confirms the suitability of using the detection of fecal-oral transmitted viruses as a marker of human fecal contamination in water matrices and indicates the spread of pathogenic viruses occurring in an alleged area of environmental protection. 相似文献
52.
Use of ecosystem information to improve soil organic carbon mapping of a Mediterranean island 总被引:1,自引:0,他引:1
Detailed maps of soil C are needed to guide sustainable soil uses and management decisions. The quality of soil C maps of Italian Mediterranean areas may be improved and the sampling density reduced using secondary data related to the nature of the ecosystem. The current study was conducted to determine: (i) the improvements obtainable in mapping soil C over a Mediterranean island by using ecosystem features and (ii) the effect of different sampling densities on the map accuracy. This work relied on field sampling (n=164) of soil properties measured over the island of Pianosa (Central Italy). Statistical analysis assessing the relationship between soil properties and ecosystem features revealed that the conceptual model of ecosystems defined on the basis of environmental features such as vegetation cover, land use, and soil type was mainly related to the variation of soil organic carbon (OC) content and to the type of Mediterranean environment. The distribution of ecosystems was used to improve the accuracy of soil OC maps obtainable by a simple interpolation approach (ordinary kriging). Substantial improvement was obtained by: (i) stratification into ecosystem types and (ii) applying locally calibrated regressions to satellite imagery that introduced both inter-ecosystem and intra-ecosystem information linked to vegetation features. This study showed that interpolation methods using information on ecosystem distribution can produce accurate maps of soil OC in Mediterranean environments, mostly because of the linkage between soil OC and vegetation types, which are spatially fragmented and heterogeneous. 相似文献
53.
Chelator-mediated Fenton reactions (CMFRs) were used to decolorize a biodegradable-resistant polymeric dye (Poly R-478). Screening of different iron chelators was performed on Fe(3+)-reduction activity. All chelators showed Fe(3+)-reduction activity over a wide range of pH (2-7) and each mol of catecholate chelators (3,4-dihydroxiphenilacetic acid--DOPAC and 2,3-dihydroxibenzoic acid--DHBA) reduced about 5-6 moles of Fe(3+) whereas hydroxamate chelators (acetohydroxamic acid-AHA and desferrioxamine B-DFB) reduced Fe(3+) stoichiometrically. The most effective decolorization of Poly R-478 was achieved by CMFR using catecholate chelators. In addition, a 2(4) factorial design was performed with the aim of evaluating the effects of the variables considered in this study (pH, [DOPAC], [Fe(3+)] and [H(2)O(2)]) and optimizing the dye decolorization, using response surface methodology. Statistical analysis of results showed that, in the range studied, except for Fe(3+), all variables have a significant effect on dye decolorization. A second-order model is proposed to represent the Poly R-478 decolorization. At optimum conditions, complete decolorization of the dye (degradation of the chromophoric group) and also complete chemical degradation of the dye was observed. 相似文献
54.
The effects of compost prepared from waste material of banana plants on the nutrient contents of banana leaves 总被引:2,自引:0,他引:2
Doran I Sen B Kaya Z 《Journal of environmental biology / Academy of Environmental Biology, India》2003,24(4):437-444
In this study, the possible utilization of removed shoots and plant parts of banana as compost after fruit harvest were investigated. Three doses (15-30-45 kg plan(-1)) of the compost prepared from the clone of Dwarf Cavendish banana were compared with Farmyard manure (50 kg plant(-1), Mineral fertilizers (180 g N + 150 g P + 335 g K plant(-1)) and Farmyard manure + Mineral fertilizers (25 kg FM + 180 g N + 150 g P + 335 g K plant(-1)) which determined positive effects on the nutrient contents of banana leaves. The banana plants were grown under a heated glasshouse and in a soil with physical and chemical properties suitable for banana growing. The contents of N, P, K and Mg in compost and in farmyard manure were found to be similar. Nitrogen, phosphorus and potassium contents of leaves in all applications except control, and Ca, Mg, Fe, Zn, Mn, Cu contents in all applications were determined between optimum levels of reference values. There were positive correlations among some nutrient contents of leaves, growth, yield and fruit quality characteristics. Farmyard manure, Farmyard manure + Mineral fertilizers and 45 kg plant(-1) of compost increased the nutrient contents of banana leaves. According to obtained results, 45 kg plant(-1) of compost was determined more suitable in terms of economical production and organic farming than the other fertiliser types. 相似文献
55.
Dianne Cook Carolina Cruz-Neira Bradley D. Kohlmeyer Uli Lechner Nicholas Lewin Laura Nelson Anthony Olsen Sue Pierson Jürgen Symanzik 《Environmental monitoring and assessment》1998,51(1-2):441-450
Geography inherently fills a 3D space and yet we struggle with displaying geography using, primarily, 2D display devices. Virtual environments offer a more realistically-dimensioned display space and this is being realized in the expanding area of research on 3D Geographic Information Systems (GISs). Traditionally, a GIS has only limited tools for statistical analysis, and 3D GIS research has concentrated on the visualization of the geographical terrain. Here we discuss linking multivariate statistical graphics to geography in the highly immersive C2 virtual reality environment at Iowa State University using mid-Atlantic streams data. 相似文献
56.
The European Water framework directive (WFD) is probably the most important environmental management directive that has been enacted over the last decade in the European Union. The directive aims at achieving an overall good ecological status in all European water bodies. In this article, we discuss the implementation steps of the WFD and their implications for environmental engineering practice while focusing on rivers as the main receiving waters. Arising challenges for engineers and scientists are seen in the quantitative assessment of water quality, where standardized systems are needed to estimate the biological status. This is equally of concern in engineering planning, where the prediction of ecological impacts is required. Studies dealing with both classification and prediction of the ecological water quality are reviewed. Further, the combined emission–water quality approach is discussed. Common understanding of this combined approach is to apply the most stringent of either water quality or emission standard to a certain case. In contrast, for example, the Austrian water act enables the application of only the water quality based approach - at least on a temporary basis. 相似文献
57.
58.
Pollution correlated modifications of liver antioxidant systems and histopathology of fish (Cyprinidae) living in Seyhan Dam Lake, Turkey 总被引:1,自引:0,他引:1
Specimen of freshwater fish (Cyprinidae) was collected from polluted and clean areas in dam Lake of Seyhan. Ten (n=10) fish were taken from each site. Liver preparations of fish from the two sources were comparatively assayed for glutathione-S-transferase (GST), lactic dehydrogenase (LDH), catalase (CAT), glucose-6-phosphate dehydrogenase (G6PDH), superoxide dismutase (SOD) and malondialdehyde (MDA). All systems were significantly (p<0.1) affected at the polluted site. The microscopic examination of the liver tissues of the fish living in the polluted area showed mononuclear inflammatory cell infiltration, cloudy degenerations, congestions and also micro- and macrovesicular fatty degenerations. These results provide evidence that both biochemical parameters and histopathological observations can be assumed as sensitive indicators of fish liver metabolism for polluted areas. 相似文献
59.
210Pb geochronology and trace metal fluxes (Cd, Cu and Pb) in the Gulf of Tehuantepec, South Pacific of Mexico 总被引:1,自引:0,他引:1
Ruiz-Fernández AC Páez-Osuna F Machain-Castillo ML Arellano-Torres E 《Journal of environmental radioactivity》2004,76(1-2):161-175
Distributions of Al, Cd, Cu, Fe, Li, Mn and Pb were analyzed in a sediment core collected in the Gulf of Tehuantepec, an important fisheries region located in the South Pacific of Mexico, where data on metal accumulation and accretion rates were previously almost nonexistent. Depth profiles of metal concentrations were converted to time-based profiles by using a 210Pb-derived vertical accretion rate, estimated to be 0.05 cm year(-1) on the average. Sediments were dated up to 8 cm depth, corresponding to a layer of ca. 140 years old. The historical changes of metal accumulation along the sediment core have shown a moderate enrichment of Cd, Cu and Pb concentrations at present, of about threefold the corresponding background concentrations. Chronological trace metal records showed that metal fluxes have increased over the last 20 years, reaching the maximum values at present of 2.5, 22.5 and 45.8 (microg cm(-2) year(-1)) for Cd, Pb and Cu, respectively. These increments in metal fluxes are likely influenced by the development of anthropogenic land-based activities since over this period of time oil production activities in the region have had a significant development. 相似文献
60.
Use of structured expert judgment to forecast invasions by bighead and silver carp in Lake Erie
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Marion E. Wittmann Roger M. Cooke John D. Rothlisberger Edward S. Rutherford Hongyan Zhang Doran M. Mason David M. Lodge 《Conservation biology》2015,29(1):187-197
Identifying which nonindigenous species will become invasive and forecasting the damage they will cause is difficult and presents a significant problem for natural resource management. Often, the data or resources necessary for ecological risk assessment are incomplete or absent, leaving environmental decision makers ill equipped to effectively manage valuable natural resources. Structured expert judgment (SEJ) is a mathematical and performance‐based method of eliciting, weighting, and aggregating expert judgments. In contrast to other methods of eliciting and aggregating expert judgments (where, for example, equal weights may be assigned to experts), SEJ weights each expert on the basis of his or her statistical accuracy and informativeness through performance measurement on a set of calibration variables. We used SEJ to forecast impacts of nonindigenous Asian carp (Hypophthalmichthys spp.) in Lake Erie, where it is believed not to be established. Experts quantified Asian carp biomass, production, and consumption and their impact on 4 fish species if Asian carp were to become established. According to experts, in Lake Erie Asian carp have the potential to achieve biomass levels that are similar to the sum of biomasses for several fishes that are harvested commercially or recreationally. However, the impact of Asian carp on the biomass of these fishes was estimated by experts to be small, relative to long term average biomasses, with little uncertainty. Impacts of Asian carp in tributaries and on recreational activities, water quality, or other species were not addressed. SEJ can be used to quantify key uncertainties of invasion biology and also provide a decision‐support tool when the necessary information for natural resource management and policy is not available. El Uso de Juicio Experto Estructurado para Predecir Invasiones de Carpas Asiáticas en el Lago Erie 相似文献