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21.
Ecological science contributes to solving a broad range of environmental problems. However, lack of ecological literacy in practice often limits application of this knowledge. In this paper, we highlight a critical but often overlooked demand on ecological literacy: to enable professionals of various careers to apply scientific knowledge when faced with environmental problems. Current university courses on ecology often fail to persuade students that ecological science provides important tools for environmental problem solving. We propose problem-based learning to improve the understanding of ecological science and its usefulness for real-world environmental issues that professionals in careers as diverse as engineering, public health, architecture, social sciences, or management will address. Courses should set clear learning objectives for cognitive skills they expect students to acquire. Thus, professionals in different fields will be enabled to improve environmental decision-making processes and to participate effectively in multidisciplinary work groups charged with tackling environmental issues.  相似文献   
22.
We report the preparation of poly(3,4-ethylene dioxythiophene) (PEDOT)-modified polyvinylidene fluoride electrospun fibers and their use as a novel adsorbent material for the removal of the anionic dye Methyl Orange (MO) from aqueous media. This novel adsorbent material can be used to selectively remove MO on a wide pH range (3.0–10.0), with a maximum capacity of 143.8 mg/g at pH 3.0. When used in a recirculating filtration system, the maximum absorption capacity was reached in a shorter time (20 min) than that observed for batch mode experiments (360 min). Based on the analyses of the kinetics and adsorption isotherm data, one can conclude that the predominant mechanism of interaction between the membrane and the dissolved dye molecules is electrostatic. Besides, considering the estimated values for the Gibbs energy, and entropy and enthalpy changes, it was established that the adsorption process is spontaneous and occurs in an endothermic manner. The good mechanical and environmental stability of these membranes allowed their use in at least 20 consecutive adsorption/desorption cycles, without significant loss of their characteristics. We suggest that the physical-chemical characteristics of PEDOT make these hybrid mats a promising adsorbent material for use in water remediation protocols and effluent treatment systems.  相似文献   
23.

In Brazil, specifically in the Doce River basin, there is still a great lack of studies on temporal and spatial trends in water quality, since the water quality in the monitoring campaigns is basically evaluated when it comes down to the concentrations of monitored variables. In this sense, the objective of this work was to perform a temporal and spatial trend analysis of water quality data in the Minas Gerais portion of the Doce River basin, Brazil. For this, the Mann–Kendall, seasonal Mann–Kendall and Spearman correlation tests were used in the temporal analysis and the cluster analysis in the spatial analysis. In the analysis of temporal trends, the analyses were performed using the values of the National Sanitation Foundation Water Quality Index (NSFWQI) and the variables that compose it. In the analysis of spatial trends, the stations were evaluated only based on the WQI. With the results of the analysis of temporal trend, it was identified that most stations did not present a statistically significant trend for the WQI. In the stations that presented trends of quality reduction, most of them are in densely populated areas, demonstrating the strong influence of the poor sanitary conditions of the municipalities to the water quality of the basin. When analyzing the variables that compose the WQI, the results found for nitrate demonstrated that water quality deterioration is also affected by the diffuse pollution originating from farming areas. The results for Escherichia coli reinforced the impact of the discharge of domestic effluents and demonstrated the absence of a significative trend is still of concern because it can represent the maintenance of a degradation state in the water bodies. In the spatial trend analysis, the CA grouped the monitoring stations into six clusters based on their similarity among the WQI values, and, together with the results of the other analyses, it was verified that the Caratinga River basin (UGRH5 Caratinga) presented the highest degree of pollution. It was also possible to identify five stations that can be reallocated or deactivated since they have similarities with other stations located in the same watercourse.

  相似文献   
24.
Environmental Science and Pollution Research - Mg-Fe layered double hydroxide intercalated with chloride (Mg-Fe-Cl LDH) was synthetized, characterized, and evaluated as adsorbent to remove nitrate...  相似文献   
25.
Environmental Science and Pollution Research - Water contamination by discharge of untreated or poorly treated wastewater into water bodies is a current issue that may cause harm to humans. Water...  相似文献   
26.
Environmental Science and Pollution Research - Exposure of geomaterials to acidic leachates may compromise their structure and functionality due to changes in physicochemical, mineralogical, and...  相似文献   
27.
Portions of the Boulder River watershed contain elevated concentrations of arsenic, cadmium, copper, lead, and zinc in water, sediment, and biota. We measured concentrations of As, Cd, Cu, Pb, and Zn in biofilm and macroinvertebrates, and assessed macroinvertebrate assemblage and aquatic habitat with the objective of monitoring planned remediation efforts. Concentrations of metals were generally higher in downstream sites compared with upstream or reference sites, and two sites contained metal concentrations in macroinvertebrates greater than values reported to reduce health and survival of resident trout. Macroinvertebrate assemblage was correlated with metal concentrations in biofilm and macroinvertebrates. However, macroinvertebrate metrics were significantly correlated with a greater number of biofilm metals (8) than metals in invertebrates (4). Lead concentrations in biofilm appeared to have the most significant impact on macroinvertebrate assemblage. Metal concentrations in macroinvertebrates were directly proportional to concentrations in biofilm, indicating biofilm as a potential surrogate for monitoring metal impacts in aquatic systems.  相似文献   
28.
Febros river water was sampled weekly, during 35 successive weeks, and analyzed for microbiological (total coliforms, faecal coliforms, faecal streptococci and enterococci) and chemical-physical (ammonia and temperature) parameters. All microbiological parameters were highly correlated with each other and with ammonia, suggesting that the simultaneous determination of all variables currently in use in the evaluation of the microbiological quality of waters is probably redundant, and could be simplified, and that ammonia should be tested as a sentinel parameter of the microbiological pollution load of Febros river. From the strains isolated from positive tubes of the faecal coliforms test (multiple tube fermentation technique) and retested in this assay, Escherichia coli, Klebsiella oxytoca and Klebsiella pneumoniae subsp. pneumoniae strains were positive, indicating that the faecal coliforms test is not totally specific for Escherichia coli, and can detect other bacteria. Considering that these Klebsiella spp. are not necessarily of faecal origin, it was concluded that the faecal coliforms test can overestimate true faecal pollution. From the strains isolated from positive tubes of the faecal coliforms procedure, only Escherichia coli strains were clearly positive in the β-D-glucuronidase test. All other species were negative or very weakly positive, suggesting that the assay of the β-D-glucuronidase activity is less prone to false positives than the faecal coliforms test in the quantification of Escherichia coli in environmental waters.  相似文献   
29.
Background. The effect of physical exercise in the workplace (PEW) on health promotion of workers is contradictory. Objective. To evaluate the effects of the PEW in musculoskeletal disorders (MSDs), perception of stress and quality of life in workers. Methods. The participants were divided into two groups: control group (n?=?46) including non-participant workers of the PEW program, and PEW group (n?=?50) including workers who regularly participate in the exercise program. All workers answered the Nordic general questionnaire, the perceived stress scale and the quality-of-life questionnaire. Results. The PEW group reported a lower prevalence of MSDs for the trunk in the last 7 days and 12 months (p?=?0.021 and p?=?0.001, respectively), and for the upper limbs in the last 12 months (p?=?0.001) compared with the control group. The results for the perception of stress and quality of life showed no significant differences between the groups. Conclusion. PEW is a potential method to reduce MSDs in workers, but it was not efficient in reducing stress levels or improving the quality of life of the workers.  相似文献   
30.
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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