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181.
Lilian D. Steckert William E. Furtado Gabriela T. Jerônimo Scheila A. Pereira Gabriel F. A. Jesus José Luiz P. Mouriño 《Journal of environmental science and health. Part. B》2019,54(4):237-246
Fish may bioaccumulate contaminants from the aquatic environment and extend them to the food chain provoking risks to human health. This study evaluated the microbiological parameters of the pond´s water and trace elements concentrations in samples of water, sediment, feed and muscle of farmed Nile tilapia used for human consumption in southern Brazil. A total of 240 fish were collected from 12 tilapia farms. Sediment, tank water and dry ration used in the animals' diet were collected for analysis. Analysis were performed by Energy Dispersion X-ray Fluorescence (EDXRF), Inductively Coupled Plasma Mass Spectrometer (ICP-MS), Induced Coupled Plasma Optical Emission Spectrometer (ICP-OES), and Atomic Absorption Spectrometer (AAS-VGA). In addition, the microbiological analysis of the water was carried out. The concentrations of Se, I, Fe, Cu and Zn in fish muscle were higher than the recommended by the Brazilian legislation, considering the advised daily intake for adults. The arsenic element had concentrations above the limit stipulated by the present Brazilian legislation, observed in all samples of muscle, sediment and tank water highlighting a possible environmental and fish contamination by the toxic element. Moreover, the arsenic concentration in the water presented a positive correlation (ρ?=?0.33) with arsenic in the muscle, suggesting that tilapia is a good environmental bioindicator, once they properly reflect the levels of arsenic in the water. It is suggested to perform an arsenic speciation for quantification of the inorganic form and accurate assessment of the degree of toxicity in the muscle samples and risks it can bring to human health. Regarding the other potentially toxic elements (Hg, Pb and Cd), and microbiological analysis of water it was verified that the consumption of the fish in question does not raise risks, since the values are within a quality benchmark established by law. The concentration of total and fecal coliforms in pond´s water in the facilities was in agreement with the microbiological indexes required by the legislation of CONAMA class II. Western region presented the lowest concentrations of fecal coliforms when compared to the other regions. There was no significant difference in the microbiological counts of total heterotrophic bacteria, Vibrio spp. and Pseudomonas spp. among the regions. 相似文献
182.
Iraklis Argyriou Jonathan B. Justice William Latham Robert Warren 《Local Environment》2017,22(12):1461-1478
Cities throughout the world are key sites for energy sustainability activities. However, analysis of such efforts to date has focused on a sub-set of atypical cities: early adopters and/or world cities. This article undertakes a case-study analysis for an ordinary city, Philadelphia, PA in order to assess the extent to which prior research provides adequate policy explanation for ordinary cities and to gain empirical insight on two under-researched aspects: policy actors, and the policy-making and implementation sites (action sites) for urban energy sustainability. Overall, the types of policy drivers, modes of governance, and enabling factors and barriers in the Philadelphia case fit with prior studies. Focusing on actors and action sites, however, offers insight on the city’s relative policy-making approach based on “non-controversy”, the key role of third-sector actors in both policy-making and implementation, and the diversification of action sites through external-level policy-making operationalised locally nevertheless at the expense of reduced control by urban actors. These findings lead to recommendations for urban energy sustainability research and practice. 相似文献
183.
Kristan Cockerill William P. Anderson Jr. F. Claire Harris Kelli Straka 《Journal of the American Water Resources Association》2017,53(3):707-724
Research increasingly highlights cause and effect relationships between urbanization and stream conditions are complex and highly variable across physical and biological regions. Research also demonstrates stormwater runoff is a key causal agent in altering stream conditions in urban settings. More specifically, thermal pollution and high salt levels are two consequences of urbanization and subsequent runoff. This study describes a demonstration model populated with data from a high gradient headwaters stream. The model was designed to explain surface water‐groundwater dynamics related to salinity and thermal pollution. Modeled scenarios show long‐term additive impacts from salt application and suggest reducing flow rates, as stormwater management practices are typically designed to do, have the potential to greatly reduce salt concentrations and simultaneously reduce thermal pollution. This demonstration model offers planners and managers reason to be confident that stormwater management efforts can have positive impacts. 相似文献
184.
Charles D. Ikenberry William G. Crumpton Jeffrey G. Arnold Michelle L. Soupir Philip W. Gassman 《Journal of the American Water Resources Association》2017,53(6):1267-1280
The ability to accurately simulate flow and nutrient removal in treatment wetlands within an agricultural, watershed‐scale model is needed to develop effective plans for meeting nutrient reduction goals associated with protection of drinking water supplies and reduction of the Gulf of Mexico hypoxic zone. The objectives of this study were to incorporate new equations for wetland hydrology and nutrient removal in Soil and Water Assessment Tool (SWAT), compare model performance using original and improved equations, and evaluate the ramifications of errors in watershed and tile drain simulation on prediction of NO3‐N dynamics in wetlands. The modified equations produced Nash‐Sutcliffe Efficiency values of 0.88 to 0.99 for daily NO3‐N load predictions, and percent bias values generally less than 6%. However, statistical improvement over the original equations was marginal and both old and new equations provided accurate simulations. The new equations reduce the model's dependence on detailed monitoring data and hydrologic calibration. Additionally, the modified equations increase SWAT's versatility by incorporating a weir equation and an irreducible nutrient concentration and temperature coefficient. Model improvements enhance the utility of SWAT for simulating flow and nutrients in wetlands and other impoundments, although performance is limited by the accuracy of inflow and NO3‐N predictions from the contributing watershed. Editor's note : This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series. 相似文献
185.
John I. “Hans” Gilderbloom Gregory D. Squires William Riggs Stella Čapek 《Local Environment》2017,22(7):894-899
Each year governments and industry around the globe spend billions of dollars in search of treatments and cures for diseases that shorten lives, which often means gadgets, implants, radiation and pills. These “cures”, do not get to the root of the problem. Perhaps it is time for us to adjust our thinking to be more proactive instead of reactive in public health. Perhaps we need to consider confronting environmental pollution of air, soil and water at a local level. As the Physicians for Social Responsibility point out, we should be “preventing what we cannot cure”. One such preventive measure is ensuring that our communities, including our poor inner-city neighbourhoods, enjoy a clean environment. We challenge local and national policy-makers to respond to the global call and to take action to address environmental toxins; to take local action to ameliorate the pollution of the air, water and soil in so many of our nation’s neighbourhoods. A person’s neighbourhood, and the proximity of dangerous environmental contaminants within it, is a powerful predictor of how long s/he will live. While situations like the poisoning of the water in Flint, Michigan have gotten some attention, they are generally treated as the exception rather than a reflection of real environmental hazards that exist in the west. Moreover we wonder why more endemic issues of neighbourhood environmental contamination that shorten human lives are not a priority for local action or that it is not linked to disproportionate production of greenhouse gases that cause climate change/warming/chaos. 相似文献
186.
William S. Cain Roland Schmidt 《Atmospheric environment (Oxford, England : 1994)》2009,43(16):2591-2601
The US EPA has exempted t-butyl acetate from VOC regulations, which increases the likelihood that it may replace other solvents in some settings. This investigation probes its chemosensory properties. In Study 1, subjects (n = 29) sought to detect the odor of t-butyl acetate and of n-butyl acetate in forced-choice testing of stable concentrations, analytically confirmed. Subjects sniffed from cones with a high enough volumetric flow to insure against dilution by nonodorized air. A subject made hundreds of judgments, enough for a psychometric function for each material. The points of 50% detection above chance (“threshold”) occurred at 8 and 2 ppb for t-butyl acetate and n-butyl acetate, respectively. In study 2, subjects (n = 26) sought to detect vapor with the eye via chemesthesis (sensory irritation) in 10-s exposures. Detection at 50% occurred at 177 and 113 ppm for t-butyl acetate and n-butyl acetate, respectively, more than 10,000 times above that for odor detection. The protocols produced results of uncommon precision compared to those in often-misleading archival databases. The nose exhibits much higher sensitivity than the databases indicate. The collections rarely exhibit accuracy better than ±1000%. Collection of accurate data for a VOC can ironically bring on stricter regulation for just it, a situation that calls for a strategy to improve the database by collection of new data, importation of better data, and development of quantitative structure–activity modeling. 相似文献
187.
Hui Li Fazlay Faruque Worth Williams Mohammad Al-Hamdan Jeffrey Luvall William Crosson Douglas Rickman Ashutosh Limaye 《Atmospheric environment (Oxford, England : 1994)》2009,43(28):4303-4310
Aerosol optical depth (AOD), an indirect estimate of particulate matter using satellite observations, has shown great promise in improving estimates of PM2.5 (particulate matter with aerodynamic diameter less than or equal to 2.5 μm) surface. Currently, few studies have been conducted to explore the optimal way to apply AOD data to improve the model accuracy of PM2.5 in a real-time air quality system. We believe that two major aspects may be worthy of consideration in that area: 1) an approach that integrates satellite measurements with ground measurements in the estimates of pollutants and 2) identification of an optimal temporal scale to calculate the correlation of AOD and ground measurements. This paper is focused on the second aspect, identifying the optimal temporal scale to correlate AOD with PM2.5. Five following different temporal scales were chosen to evaluate their impact on the model performance: 1) within the last 3 days, 2) within the last 10 days, 3) within the last 30 days, 4) within the last 90 days, and 5) the time period with the highest correlation in a year. The model performance is evaluated for its accuracy, bias, and errors based on the following selected statistics: the Mean Bias, the Normalized Mean Bias, the Root Mean Square Error, Normalized Mean Error, and the Index of Agreement. This research shows that the model with the temporal scale: within the last 30 days, displays the best model performance in a southern multi-state area centered in Mississippi using 2004 and 2005 data sets. 相似文献
188.
Sustainability assessment (SA) is a holistic and long-range strategic instrument capable of assisting policy-making in electing,
and deciding upon, future development priorities. The outcomes of an SA process become more relevant and strengthened when
conducted with multi-stakeholder engagement, which provides for multiple dialogues and perspectives. This was the object of
research of the SA team in the context of BioScene (Scenarios for Reconciling Biodiversity Conservation with Declining Agriculture Use in Mountain Areas in Europe), a three-year project (2002–2005) funded by the European Union 5th Framework Program, which aimed to investigate the implications
of agricultural restructuring and decline for biodiversity conservation in the mountain areas of Europe, using three distinct
methodological streams: the ecological, the socio-economic, and the SA approaches. The SA approach drew on the previous two
to assess the importance for biodiversity management of different scenarios of agri-environmental change and rural policy
in six countries (France, Greece, Norway, Slovakia, Switzerland, and the United Kingdom), develop causal chains, include stakeholder
views, and identify potential contributions for, or conflicts with, sustainability. This article tells how SA was used, what
sustainability meant in each study area through different objectives of sustainability considered, discusses the methods used
in SA, and the benefits arising. The SA was conducted by a team independent of any study area, who developed and oversaw the
application of the SA methodology, assisting national teams, and developing a cross-country understanding of the sustainability
of proposed scenarios in the different geographical and social contexts, and their implications for policy-making. Finally,
it reflects on the persistent challenges of interdisciplinary research, compounded by multi-cultural teams, and concludes
on the BioScene’s lessons for the further development and application of SA.
相似文献
William R. SheateEmail: |
189.
M. Reza Ghanbarpour Keith William Hipel 《Environment, Development and Sustainability》2009,11(2):241-253
Environmental disputes arise due to opposing views of various groups about their environmental concerns and their economic
or developmental interests. Development and protection of the environment constitute two main contradictory objectives within
the sustainable development paradigm, which are often in conflict. The decision support system, GMCR II, which implements
the graph model for conflict resolution, is employed to model and analyze an environmental dispute arising over the construction
of a new freeway between the Iranian capital, Tehran, and the city of Chalous located in the north of the country. This study
demonstrates that the graph model for conflict resolution can be used as a methodology to promote a reasonable balance between
economic development and environmental protection from a strategic viewpoint. In addition to systematically modelling the
conflict by putting the existing information into proper perspective, it is shown how conflict analysis can be used for comparing
alternative scenarios and predicting possible future outcomes.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
190.
Nitrogen limited biobarriers remove atrazine from contaminated water: laboratory studies 总被引:1,自引:0,他引:1
Atrazine is one of the most frequently used herbicides. This usage coupled with its mobility and recalcitrant nature in deeper soils and aquifers makes it a frequently encountered groundwater contaminant. We formed biobarriers in sand filled columns by coating the sand with soybean oil; after which, we inoculated the barriers with a consortium of atrazine-degrading microorganisms and evaluated the ability of the barriers to remove atrazine from a simulated groundwater containing 1 mg L(-1) atrazine. The soybean oil provided a carbon rich and nitrogen poor substrate to the microbial consortium. Under these nitrogen-limiting conditions it was hypothesized that bacteria capable of using atrazine as a source of nitrogen would remove atrazine from the flowing water. Our hypothesis proved correct and the biobarriers were effective at removing atrazine when the nitrogen content of the influent water was low. Levels of atrazine in the biobarrier effluents declined with time and by the 24th week of the study no detectable atrazine was present (limit of detection<0.005 mg L(-1)). Larger amounts of atrazine were also removed by the biobarriers; when biobarriers were fed 16.3 mg L(-1) atrazine 97% was degraded. When nitrate (5 mg L(-1) N), an alternate source of nitrogen, was added to the influent water the atrazine removal efficiency of the barriers was reduced by almost 60%. This result supports the hypothesis that atrazine was degraded as a source of nitrogen. Poisoning of the biobarriers with mercury chloride resulted in an immediate and large increase in the amount of atrazine in the barrier effluents confirming that biological activity and not abiotic factors were responsible for most of the atrazine degradation. The presence of hydroxyatrazine in the barrier effluents indicated that dehalogenation was one of the pathways of atrazine degradation. Permeable barriers might be formed in-situ by the injection of innocuous vegetable oil emulsions into an aquifer or sandy soil and used to remove atrazine from a contaminated groundwater or to protect groundwater from an atrazine spill. 相似文献