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101.
Fragile coastal areas suffer from human activities. Environmental quality is one of the most important aspects in a tourist destination of sun and sand. The quality of bathing water and sand became indicators in the worldwide competition of beach destinations. We studied the water and sand quality along the beach of Puerto Velero, in northern Colombia. Water and sand beach quality were monitored during thirteen months. This allowed identifying the most significant sources of pollution along the beach, and understanding the interrelationship between tourism and the effects on the environment. Linear correlations allow assessing the association between the number of visitors and the physicochemical and microbiological parameters. The number of visitors was directly correlated with the presence of grease and oils, both in water and sand, as well as with fecal coliforms in water. A relation between the suspended solids and the presence of fecal coliforms in water and sand was observed. This statistical approach allows understanding the origin of beach sand and swimming water pollution at tourist beaches. Overall, sand quality has an important influence and is directly related to the water quality of the beach. Both the number of tourists and their activities are main factors explaining the contamination of the water and sand. This shows the importance of management of waste and wastewater in combination with awareness raising initiatives. More research should include monitoring and evaluating of both water and sand beach and provide data to revise the existing legal framework.  相似文献   
102.
Representative Life-Cycle Inventories (LCIs) are essential for Life-Cycle Assessments (LCAs) quality and readiness. Because energy is such an important element of LCAs, appropriate LCIs on energy are crucial, and due to the prevalence of hydropower on Brazilian electricity mix, the frequently used LCIs are not representative of the Brazilian conditions. The present study developed a LCI of the Itaipu Hydropower Plant, the major hydropower plant in the world, responsible for producing 23.8% of Brazil's electricity consumption. Focused on the capital investments to construct and operate the dam, the LCI was designed to serve as a database for the LCAs of Brazilian hydroelectricity production. The life-cycle boundaries encompass the construction and operation of the dam, as well as the life-cycles of the most important material and energy consumptions (cement, steel, copper, diesel oil, lubricant oil), as well as construction site operation, emissions from reservoir flooding, material and workers transportation, and earthworks. As a result, besides the presented inventory, it was possible to determine the following processes, and respective environmental burdens as the most important life-cycle hotspots: reservoir filling (CO2 and CH4 emission; land use); steel life-cycle (water and energy consumption; CO, particulates, SOx and NOx emissions); cement life-cycle (water and energy consumption; CO2 and particulate emissions); and operation of civil construction machines (diesel consumption; NOx emissions). Compared with another hydropower studies, the LCI showed magnitude adequacy, with better results than small hydropower, which reveals a scale economy for material and energy exchanges in the case of Itaipu Power Plant.  相似文献   
103.
Since the tragic event on September 11, 2001 (9/11), homeland security has been the center of major attention not only in the United States but also around the world. Among homeland security agenda, more concerns on drinking water system have been drawn into the forefront attention from the public and water industry. Governmental agencies have been called upon to strongly protect the water resources from becoming a possible terror target. The online monitoring of a water system offers the potential to reduce the possible danger from a terrorist contamination as well as from unintentional chemical spills. As potential terrorist contaminants, seven chemical compounds (aldicarb, cycloheximide, dicrotophos, nicotine, sodium arsenate, sodium cyanide, and sodium fluoroacetate) were studied at different doses, in order to determine their detectability when they are present in a water system, including intake, treatment, and distribution. These contaminants were monitored by measuring simple water quality parameters such as conductivity, pH, chlorine residual, turbidity, total organic carbon (TOC), and UV254. Results indicated that the contaminants used for the study were detected at certain toxicity concentrations through the online water quality monitoring method. This method provides a useful tool for watching water resources against possible terror attacks, and also keeping safe water quality.  相似文献   
104.
The aim of this study was to investigate hepatitis A virus (HAV), hepatitis E (HEV), and rotavirus (RV) in fresh and processed meat traded on the border of Brazil with Argentina and Uruguay. In total, 159 samples of raw and processed foods of animal origin were collected in Paso de los Libres, Argentina (n?=?53 raw meat, n?=?24 processed meat) and Rivera, Uruguay (n?=?55 raw meat, n?=?18 processed meat), or were seized by the Brazilian International Agricultural Surveillance System—VIGIAGRO (Brazil–Argentina border) (n?=?8 raw meat, n?=?1 bush meat). All samples were tested for the presence of HAV, HEV, and RV genomes. HAV genes were detected in 18.23% of samples and RV genes in 23.89%. No HEV-positive samples were detected. HAV was also detected in two of the VIGIAGRO samples. Processed meats from Argentina and Uruguay had a higher rate of HAV and RV than raw meat (P?>?0.05). The median HAV in the Argentinian and Uruguayan samples was 6.9?×?104 and 3.5?×?103 copies/g, respectively. The presence of RV viral genes in raw meats from Argentina was significant, and this was not observed in processed meats. The presence of HAV and RV genes in a significant portion of products from Argentina and Uruguay is a potential source of human infection. This also indicates precarious conditions of acquisition, processing, and manipulation, which could be improved by improved regulation of food across borders.  相似文献   
105.
Periodic assessment of progress toward established policy goals is crucial to understanding whether the applied efforts are effective. In Europe, the Water Framework Directive (WFD) adopted in year 2000 set ambitious environmental objectives to be achieved by the end of 2015 through the implementation of Integrated Water Resources Management (IWRM) principles. While at this stage it is premature to measure the impact of this Directive in terms of environmental outcomes, it is nonetheless important to develop indicators in order to monitor whether water management practices throughout Europe are aligning towards IWRM. This article presents the methodological development of the Water and Wetland Index, a comparative water policy assessment by environmental NGOs that was carried out in 2002–2003, and highlights the interest of repeating it in 2015, when the first WFD planning cycle will be completed.  相似文献   
106.
Although our understanding of how animal personality affects fitness is incomplete, one general hypothesis is that personality traits (e.g. boldness and aggressiveness) contribute to competitive ability. If so, then under resource limitation, personality differences will generate variation in life history traits crucial to fitness, like growth. Here, we test this idea using data from same-sex dyadic interaction trials of sheepshead swordtails (Xiphophorus birchmanni). In males, there was evidence of repeatable variation across a suite of agonistic contest behaviours, while repeatable opponent effects on focal behaviour were also detected. A single vector explains 80 % of the among-individual variance in multivariate phenotype and can be viewed as aggressiveness. We also find that aggressiveness predicts dominance—the repeatable tendency to win food in competition—and dominant individuals show faster post-trial weight gain (independently of initial size). In females, a dominance hierarchy predictive of weight gain was also found, but there was no evidence of variation in aggressiveness. While size often predicts contest outcome, our results show that individuals may sometimes grow larger because they are behaviourally dominant rather than vice versa. When resources are limited, personality traits such as aggression can influence growth, life history, and fitness through impacts on resource acquisition.  相似文献   
107.
The purpose of this paper is to study metal separation from a sample composed of a mixture of the main types of spent household batteries, using a hydrometallurgical route, comparing selective precipitation and liquid-liquid extraction separation techniques. The preparation of the solution consisted of: grinding the waste of mixed batteries, reduction and volatile metals elimination using electric furnace and acid leaching. From this solution two different routes were studied: selective precipitation with sodium hydroxide and liquid-liquid extraction using Cyanex 272 [bis(2,4,4-trimethylpentyl) phosphoric acid] as extracting agent. The best results were obtained from liquid-liquid extraction in which Zn had a 99% extraction rate at pH 2.5. More than 95% Fe was extracted at pH 7.0, the same pH at which more than 90% Ce was extracted. About 88% Mn, Cr and Co was extracted at this pH. At pH 3.0, more than 85% Ni was extracted, and at pH 3.5 more than 80% of Cd and La was extracted.  相似文献   
108.
The use of Radio Frequency IDentification Technology (RFID) in the packaging sector is an important logistical improvement regarding the advantages offered by this technology in comparison with barcodes. Nevertheless, the presence of these devices in plastic packaging, and consequently in plastic waste, can cause several problems in the recycling plants due to the materials included in these devices.In this study, the mentioned recycling constraints have been experimentally identified in a pilot scale recycling study consisting in three recycling tests with an increasing presence of RFID tags. Differences in each test were evaluated. Furthermore, the quality of the recycled material of each test was studied through the injection and testing of tests probes.The results of the pilot scale recycling tests did not show a decrease in the quality of the recycled plastic due to the presence of RFID tags. Nevertheless, several operational problems during the recycling process were observed such as the obstruction of the screens, which lessened the process yield and created process interruptions, as well as the loss of extruded plastic during the process.These recycling constraints cannot be directly extrapolated to the industrial plants due to the different working scales. Nevertheless, technological solutions are proposed in order to avoid these recycling constraints if they appear.  相似文献   
109.
In this research, we evaluated the toxic effect of metal ions on mycelial growth and phosphate-solubilising activity of soil-borne micromycetes isolated from the Phragmites australis rhizosphere using Pikovskaya-agar plates supplemented with four metal concentrations. The diameter growth rate (DGR) decreased as the metal concentration rise for all tested fungi. Trichoderma atroviride had the fastest growth rate (1.48?cm2?day?1) and was the least susceptible to Al3+, Cd2+, Cr3+, Cu2+ and Pb2+ with a median effective concentration (MEC50) of 12.19, 0.48, 4.51, 11.44 and 50.05?mM, respectively. Aspergillus japonicus was the most tolerant to Co2+, Ni2+ and Zn2+, with MEC50 values of 3.36, 1.095 and 2.34?mM, respectively. Penicillium italicum was the most tolerant to Cr6+ (MEC50?=?0.677?mM). The ability to solubilise phosphate remained, despite the decrease in the DGR, and P. italicum and Penicillium dipodomyicola had the highest Phosphate Solubilisation Indexes (PSIs) at 1.97 and 2.12, respectively. In particular, P. italicum recorded the highest PSI of all the studied isolates at 0.62?mM Cr3+ (PSI?=?4.74). A. japonicus and T. atroviride were the most tolerant isolates to all tested metals, which suggests that these isolates are promising candidates for further study with regard to mycoremediation and biofertilisation of metal-polluted soils.  相似文献   
110.
This study evaluates the spatial patterns of land occupation and their relationship to water quality in the Cuiabá River watershed, one of the main affluents of the Pantanal floodplain. The impact of farming and other land occupation forms were studied using a three year time series. Monitoring included 15 parameters at 21 stations with a total of 1266 different samples. Ten stations along the Cuiabá River were ordinated by Principal Component Analysis (PCA). For an exploratory analysis in the spatial domain, sub-basins of the Cuiabá watershed were classified according to mean concentrations of selected water quality parameters. Supervised classification of digital Landsat ETM imagery and standard GIS techniques were applied to parameterize land use and occupation according to a watershed scale. Redundancy Analysis (RDA) was then used to evaluate impacts of environmental and socio-economic factors on water quality.A Cuiabá headwater station only shows slightly elevated total coliform counts and concentrations of nutrients in the river after it passes regions of extensive cattle farming. After the confluence with the Manso River, nutrient and COD concentrations increase significantly, receiving loads from sub-basins under intensive agricultural land use, with mean annual concentrations up to 1.74 mg/L of total nitrogen (Kjedahl). Sub-watersheds with intensive fishing culture activities were shown to have significant impact on nitrogen concentrations, reaching mean concentrations of 2.66 mg/L of total nitrogen in the affluents. Most serious biological and chemical water pollution can be observed at stream outlets in the urban agglomeration of Cuiabá/Várzea Grande. Affluent pollution is reflected in the water quality of the Cuiabá River: subsequent monitoring stations in the urban area are ordinated on a gradient of increasing degradation of chemical and biological water quality. The auto-depuration capacity of the Cuiabá River is intact, but elevated concentrations of Phosphorous and Chemical Oxygen Demand can be observed as far away as the Pantanal floodplain, about 120 km downstream from the urban agglomeration.  相似文献   
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