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1.
Júlio F. Carneiro 《International Journal of Greenhouse Gas Control》2009,3(4):431-443
The double porosity model for fissured rocks, such as limestones and dolomites, has some features that may be relevant for carbon sequestration. Numerical simulations were conducted to study the influence of matrix diffusion on the trapping mechanisms relevant for the long-term fate of CO2 injected in fissured rocks. The simulations show that, due to molecular diffusion of CO2 into the rock matrix, dissolution trapping and hydrodynamic trapping are more effective in double porosity aquifers than in an equivalent porous media. Mineral trapping, although assessed indirectly, is also probably more relevant in double porosity aquifers due to the larger contact surface and longer contact time between dissolved CO2 and rock minerals. However, stratigraphic/structural trapping is less efficient in double porosity media, because at short times CO2 is stored only in the fissures, requiring large aquifer volumes and increasing the risk associated to the occurrence of imperfections in the cap-rock through which leakage can occur. This increased risk is also a reality when considering storage in aquifers with a regional flow gradient, since the CO2 free-phase will move faster due to the higher flow velocities in fissured media and discharge zones may be reached sooner. 相似文献
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Manuela Carneiro Bruno Colaço Ricardo Brandão Carla Ferreira Nuno Santos Vanessa Soeiro Aura Colaço Maria João Pires Paula A. Oliveira Santiago Lavín 《Environmental monitoring and assessment》2014,186(11):7011-7021
The accumulation of heavy metals in the environment may have a wide range of health effects on animals and humans. Thus, in this study, the concentrations of arsenic (As), cadmium (Cd), lead (Pb), and mercury (Hg) in the blood and tissues (liver and kidney) of Portuguese common buzzards (Buteo buteo) were determined by inductively coupled plasma-mass spectrometer (ICP-MS) in order to monitor environmental pollution to these elements. In general, Hg and As were the elements which appeared in the highest and lowest concentrations, respectively. A highest percentage of non-detected concentration was found for blood Cd (94.6 %) but, in turn, it was the only metal that was detected in all kidney samples. The kidney was the analyzed sample which showed the highest concentrations of each element evaluated. Statistically, significant differences among blood, liver, and kidney samples were observed for As and Cd (P?0.05). Cd concentrations in kidney and liver varied significantly with age: Adults showed higher hepatic and renal Cd concentrations than juveniles. Blood Pb concentration seems to show an association with the hunting season. Although raptors are at the top of the food chain and are thus potentially exposed to any biomagnification processes that may occur in a food web, the individuals evaluated in this study generally had low levels of heavy metals in blood and tissues. However, chronic exposure to these metals was verified. The results presented here lend weight to arguments in favor of continuous biomonitoring of metals and metalloids, since heavy metals may accumulate to levels that will pose a risk to both human health and the environment. 相似文献
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Márcia Maria Guedes Alcoforado de Moraes Anne Biewald Ana Cristina Guimarães Carneiro Gerald Norbert Souza da Silva Alexander Popp Hermann Lotze-Campen 《Regional Environmental Change》2018,18(7):1943-1955
Economic values of water for the main Public Irrigation Schemes in the sub-middle region of the São Francisco River Basin, in northeastern Brazil, are determined in this study using an integration of a global agro-economic land and water use (MAgPIE) with a local economic model (Positive Mathematical Programming). As in the latter, the water values depend on the crops grown, and as Brazilian agriculture is strongly influenced by the global market, we used a regionalized version of the global model adapted to the region in order to simulate the crop land use, which is in turn determined by changes in global demand, trade barriers, and climate. The allocation of sugarcane and fruit crops projected with climate change by the global model, showed an impact on the average yields and on the water costs in the main schemes resulting in changes in the water values locally. The economic values for all schemes in the baseline year were higher than the water prices established for agricultural use in the basin. In the future, these water values will be higher in all the schemes. The highest water values currently and in the future were identified in municipalities with a significant proportion of area growing irrigated sugarcane. Being aware of current water values of each user in a baseline year and in a projected future under global climate and socioeconomic changes, decision makers should improve water allocation policies at local scale, in order to avoid conflicts and unsustainable development in the future. 相似文献
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Mercury (Hg) is a hazardous chemical that accumulates in many cells and tissues, thereby producing toxicity. The kidney is a key target organ for Hg accumulation and toxicity. The contributing factors to Hg accumulation in humans include: (1) elemental and inorganic Hg exposure, often occurring by inhalation of Hg vapors; (2) exposure to methyl Hg (meHg), for example, through contaminated seafood; and (3) exposure to ethyl mercury (etHg) via thimerosal-containing vaccines. Systematic investigations on the toxic effects of etHg/thimerosal on the nervous system were carried out, and etHg/thimerosal emerged as a possible risk factor for autism and other neurodevelopmental disorders. There is, however, little known about the mechanisms and molecular interactions underlying toxicity of etHg/thimerosal in the kidney, which is the focus of the current review. Susceptible populations such as infants, pregnant women, and the elderly are exposed to etHg through thimerosal-containing vaccines, and in-depth study of the potential adverse effects on the kidney is needed. In general, toxicity occurring in association with different forms of Hg is related to: intracellular thiol metabolism and oxidative stress reactions; mitochondrial function; intracellular distribution and build-up of calcium; apoptosis; expression of stress proteins; and also interaction with the cytoskeleton. Available evidence for the etHg-induced toxicity in the kidney was examined, and the main mechanisms and molecular interactions of cytotoxicity of etHg/thimerosal exposure in kidney described. Such accumulating knowledge may help to indicate molecular pathways that, if modulated, may better handle Hg-mediated toxicity. 相似文献
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G. L. Carneiro D. Braz E. F. de Jesus S. M. Santos K. Cardoso A. A. Hecht Moore K. Dias da Cunha 《Environmental geochemistry and health》2013,35(3):333-340
The aim of this study was to evaluate the public and occupational exposure to radon and metal-bearing particles in museums and public buildings located in the city of Rio de Janeiro, Brazil. For this study, four buildings were selected: two historic buildings, which currently house an art gallery and an art museum; and two modern buildings, a chapel and a club. Integrated radon concentration measurements were performed using passive radon detectors with solid state nuclear track detector-type Lexan used as nuclear track detector. Air samplers with a cyclone were used to collect the airborne particle samples that were analyzed by the particle-induced X-ray emission technique. The average unattached-radon concentrations in indoor air in the buildings were above 40 Bq/m3, with the exception of Building D as measured in 2009. The average radon concentrations in indoor air in the four buildings in 2009 were below the recommended reference level by World Health Organization (100 Bq/m3); however, in 2011, the average concentrations of radon in Buildings A and C were above this level, though lower than 300 Bq/m3. The average concentrations of unattached radon were lower than 148 Bq/m3 (4pCi/L), the USEPA level recommended to take action to reduce the concentrations of radon in indoor air. The unattached-radon average concentrations were also lower than the value recommended by the European Union for new houses. As the unattached-radon concentrations were below the international level recommended to take action to reduce the radon concentration in air, it was concluded that during the period of sampling, there was low risk to human health due to the inhalation of unattached radon in these four buildings. 相似文献
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J. Carneiro L. M. Cardenas D. J. Hatch H. Trindade D. Scholefield C. D. Clegg P. Hobbs 《Environmental Chemistry Letters》2010,8(3):237-246
Nitrous oxide (N2O) affects climate change as a greenhouse gas and indirectly contributes to stratospheric ozone depletion. The main source
of N2O in soils is denitrification which requires high soil moisture, carbon and nitrate. Nitrification inhibitors can be used
to mitigate emissions of N2O from soils. In Portugal, fertilisers are often applied when soils are still relatively warm and moist conditions conducive
to denitrification. A Portuguese arable soil was inhibited with dicyandiamide, a nitrification inhibitor and the effect on
soil microbiological activity and composition was determined after 46 days. Soils were then incubated and received carbon
and ammonium under high soil water conditions and mineral N and N2O fluxes were measured during 22 days. We found that dicyandiamide decreased microbial populations and activity, but did not
alter composition. Pre-conditioning of the soil with dicyandiamide was 80% more effective in reducing fluxes of N2O than simultaneous application with fertiliser. 相似文献
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da Silva LI de Souza Sarkis JE Zotin FM Carneiro MC Neto AA da Silva Ados S Cardoso MJ Monteiro MI 《Chemosphere》2008,71(4):677-684
In this work, 24-h PM10 samples were collected in Rio de Janeiro, Brazil, and analysed for trace elements (Cd, Ce, Cu, La, Mo, Ni, Pb, Pd, Rh, Sb and Sn). The sampling was carried out at five locations (Bonsucesso; Centro, downtown city; Copacabana; Nova Igua?u and Sumaré) with different traffic densities and anthropogenic activities. An analytical method based on the EPA method for the determination of trace elements in airborne particulate matter (PM), using ultrasonic-assisted extraction and inductively coupled plasma mass spectrometry (ICP-MS) was applied. Our results suggest that vehicular traffic is the most important source of environmental pollution at the studied sites. The presence of Mo, Pd and Rh in the analysed filters reflects an additional source of pollution caused by the erosion and deterioration of automotive catalytic converters. 相似文献
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Pinheiro Samara Lima Marcelo Carneiro Bruno Costa Tavares Vanessa Câmara Volney 《Environmental science and pollution research international》2019,26(6):5738-5750
Environmental Science and Pollution Research - The port regions of the Amazon are subject to environmental impacts high shipping traffic. In October 2015, a cargo ship containing 5000 oxen sank in... 相似文献
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Belarmino?Carneiro?da?Silva Neto André?Luiz?Borba?do?Nascimento Nicola?Schiel R?mulo?Romeu?Nóbrega AlvesEmail author Antonio?Souto Ulysses?Paulino?AlbuquerqueEmail author 《Environment, Development and Sustainability》2017,19(5):1795-1813
The hunting of wild animals remains a common activity in various parts of the world, especially in rural communities with poor socioeconomic conditions. To investigate patterns of mammal hunting, this study adopted a rural community located in semiarid Brazil as a model to test whether variables such as perceived abundance, activity period (day or night) and animal biomass could influence the consumption potential of mammal taxa. For this study, a checklist/interview technique using 32 photographs of mammals recorded in the region and two photographs of species that did not occur in the region, which acted as “control” species, was used, in addition to other visual stimuli and free lists. All species presented in the photographs, with the exception of the “control” species, were recognized as occurring in the region. Fourteen species were cited as being those most hunted locally. The species cited as most hunted had an average perceived abundance higher than the group of the least-hunted species. However, there was no significant relationship between hunting of a species and its locally perceived abundance. No significant difference in hunting pressure between diurnal and nocturnal species was found, nor was a relationship between animal biomass and hunting pressure observed. Our findings suggest that perceived abundance is an important factor for choosing a resource fauna, but other factors such as intended use, meat flavor and vulnerability to hunting, among others, may influence the potential use of a species. 相似文献