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941.
This study evaluated the sources of fecal contamination in different river catchments, using a combination of microbial source tracking tools, for human, ruminant, ovine and bovine livestock, in order to define appropriate water management strategies. Every source of waterway pollution was evaluated in river water samples from one urban river catchment and two important farming regions in New Zealand. Fecal pollution was initially measured by testing Escherichia coli and evaluating the presence of human- and ruminant-associated DNA markers of Bacteroidales (BiAdo, BacHum-UCD, BacH, and BacR) and human and ruminant fecal sterols/stanols ratios. Then specific fecal pollution sources were assessed with previously reported quantitative PCR assays targeting human-, bovine-, and ovine-specific viruses: human adenoviruses (HAdV), human JC polyomaviruses, bovine polyomaviruses (BPyV), and ovine polyomaviruses (OPyV). High level of ruminant fecal contamination was detected all over the farming areas, whereas no ruminant sources were identified in the urban river sampling sites. BacR was the most frequently observed ruminant marker and OPyV and BPyV allowed the identification of ovine and bovine fecal sources. The human fecal viral marker (HAdV) was the most frequently observed human marker, highly abundant in the urban sites, and also present in farming areas. This is the first study using simultaneously the ovine and the bovine viral markers to identify and quantify both bovine and ovine fecal pollution.  相似文献   
942.
Objective: The purpose of this article is to describe a public school–based educational intervention (EI) designed to increase knowledge, improve attitudes, and change practices related to road safety.

Methods: We used a mixed-methods evaluation of a road traffic safety baseline diagnosis conducted in 4 public schools, 2 primary and 2 secondary. Research was organized into 4 phases: (1) diagnosis, (2) EI design, (3) implementation, and (4) evaluation. We used convenience sampling (n = 219 students) across schools and applied a pre-/posttest design based on quantitative and qualitative data. The former related to surveys on road safety experiences, knowledge, attitudes, and practice and the latter to observation checklists, community mapping, ethnography, and focus groups. To compare pre–post scores, we used multilevel mixed-effect ordinal logistic regressions. We developed data matrices, field notes, and systematized community mapping. We also transcribed focus group discussions, generated categories, and carried out thematic analysis.

Results: Ethnography indicated poor sidewalk conditions, no helmet or seat belt use, overcrowded public transportation, and no traffic lights or proper signals. Pedestrians did not use sidewalks and crossed streets unsafely. Subsequent to the intervention, however, the study population showed significant changes in their knowledge, practices, and attitudes. They identified road traffic incidents (RTIs) as the first cause of death among children and youth, and most understood that the solution to the problem was incumbent upon each and every individual. They also displayed increased perceptions of danger in practices such as traveling on overcrowded public transportation, failing to wear seat belts in cars and helmets on motorcycles, crossing the street while using mobile phones or playing with friends, and riding with drunk drivers. Changes varied according to gender, and students reported being able to carry out safe practices only when they were in control of the situation; for instance, as pedestrians.

Conclusions: Because safe practices depend not only on children and youth but on the adults and social environment surrounding them, it is essential to engage parents, teachers, and decision makers in efforts to reduce RTIs. This will improve the establishment of commitments to impact social reality through consistent changes and mobilize greater resources for creating more secure communities in matters of road safety.  相似文献   

943.
The aim of this study is to compare, from an environmental point of view, different alternatives for the management of municipal solid waste generated in the town of Castellón de la Plana (Spain). This town currently produces 207 ton of waste per day and the waste management system employed today involves the collection of paper/cardboard, glass and light packaging from materials banks and of rest waste at street-side containers.The proposed alternative scenarios were based on a combination of the following elements: selective collection targets to be accomplished by the year 2015 as specified in the Spanish National Waste Plan (assuming they are reached to an extent of 50% and 100%), different collection models implemented nationally, and diverse treatments of both the separated biodegradable fraction and the rest waste to be disposed of on landfills.This resulted in 24 scenarios, whose environmental behaviour was studied by applying the life cycle assessment methodology. In accordance with the ISO 14040-44 (2006) standard, an inventory model was developed for the following stages of the waste management life cycle: pre-collection (bags and containers), collection, transport, pre-treatment (waste separation) and treatment/disposal (recycling, composting, biogasification + composting, landfill with/without energy recovery). Environmental indicators were obtained for different impact categories, which made it possible to identify the key variables in the waste management system and the scenario that offers the best environmental behaviour. Finally, a sensitivity analysis was used to test some of the assumptions made in the initial life cycle inventory model.  相似文献   
944.
The popularity of ecotourism in the marine protected areas of Mexico has increased over the last 10 years; in particular there is a large development of a SCUBA diving industry in the Mexican Pacific including Isabel Island. Given the risks associated with human activity in the marine environments around this island, we propose two ecotourism management strategies: (1) the creation and use of underwater trails, and (2) the estimation of the specific tourism carrying capacity (TCC) for each trail. Six underwater trails were selected in sites that presented elements of biological, geological, and scenic interest, using information obtained during field observations. The methodology used to estimate the TCC was based upon the physical and biological conditions of each site, the infrastructure and equipment available, and the characteristics of the service providers and the administrators of the park. Correction factors of the TCC included elements of the quality of the visit and the threat and vulnerability of the marine environment of each trail (e.g., divers’ expertise, size and distance between groups of divers, accessibility, wind, coral coverage). The TCC values ranged between 1,252 and 1,642 dives/year/trail, with a total of 8,597 dives/year for all six trails. Although these numbers are higher than the actual number of recreational visitors to the island (~1,000 dives per year), there is a need for adequate preventive management if the diving sites are to maintain their esthetic appeal and biological characteristics. Such management might be initially directed toward using only the sites and the TCC proposed here.  相似文献   
945.
A glasshouse study of the coastal shrub Limoniastrum monopetalum was carried out to evaluate its tolerance and capacity to accumulate copper. We investigate the effects of Cu from 0 to 60 mmol l?1 on the growth, photosynthetic apparatus, and nutrient uptake of L. monopetalum, by measuring gas exchange, chlorophyll fluorescence parameters, photosynthetic pigments, and total copper, nitrogen, phosphorus, sulfur, calcium, and magnesium content in the plant tissues. Although L. monopetalum did not survive at 60 mmol l?1 Cu, the species demonstrated a high tolerance to Cu-induced stress, since all plants survived external Cu concentrations of up to 35 mmol l?1 and displayed similar growth in the Cu-enriched medium as in the control treatment of up to the external level of 15 mmol Cu l?1 (1,000 mg Cu l?1). The reduced growth registered in plants exposed to 35 mmol Cu l?1 can be attributed to reduced photosynthetic carbon assimilation associated with the adverse effect of the metal on the photochemical apparatus and a reduction in the absorption of essential nutrients. Copper tolerance was associated with the capacity of the plant to accumulate the metal in its roots and effectively prevent its translocation to photosynthetic tissues. L. monopetalum has the characteristics of a Cu-excluder plant and could be used in the revegetation of Cu-contaminated soils.  相似文献   
946.
Tourism can sustain high levels of employment and income, but the sector is a source of environmental and health impacts. One of the most important is the generation of municipal solid waste (MSW). However, there is a lack of studies which quantify how much the tourist population engages in total MSW and separately collected recyclables. The aim of this paper is to estimate the impact of the tourist population on MSW, both total and separately collected, for the period 1998–2010, for the Mediterranean island of Menorca (Spain). We use dynamic regressions models, including data for monthly stocks of tourists. The results show that, on average, a 1% increase in the tourist population in Menorca causes an overall MSW increase of 0.282% and one more tourist in Menorca generates 1.31 kg day?1 (while one more resident generates 1.48 kg day?1). This result could be useful to better estimate the seasonal population of different regions, since intrannual fluctuation of MSW is used as a proxy measure of actual population (the sum of residents and tourists). Moreover, an increase of 1% in the tourist population causes an increase of 0.232% in separately collected recyclables and an additional tourist generates 0.160 kg day?1. One resident selectively collects on average 47.3% more than one tourist. These results can help in the planning of waste infrastructure and waste collection services in tourist areas.  相似文献   
947.
948.
This paper describes a novel methodology for evaluating the extent to which petrol stations affect their surroundings. The method is based on the fact that the ratio of the concentrations of aliphatic and aromatic hydrocarbon pollutants in the air of the petrol stations and their surroundings (basically determined by vapor emissions from unburned gasoline) differs from the ratio found in urban air, which is mainly influenced by traffic emissions. Bearing this in mind, the spatial limit of influence of petrol stations in any direction would be the first point, moving away from the station, where the ratio becomes equal to the urban background ratio. Application of the methodology involves multipoint measuring campaigns of the air at the studied petrol station and built-up area in general and processing the data with software capable of providing isoconcentration contours. The procedure should help local authorities in terms of land management, so that a “belt” can be established around petrol stations where housing or vulnerable populations and activities such as those in schools, hospitals and community centers should be restricted.  相似文献   
949.
Events like trade fairs are a complex service activity with a considerable economic, social and environmental impact due, among other factors, to their high level of waste generation. There are few studies of the environmental impact associated with waste generation and typology. An environmental analysis methodology has been developed to characterise the waste associated with the temporary structures used at trade fair events: stands and communal spaces.This methodology has been checked in a pilot test at 6 closed trade fairs in Barcelona, with a range of between 60 and 4400 exhibitors. The methodology developed has made possible to obtain a waste generation profile according to the size of the fair and the types of stands. The stages with the largest amount of temporary structure wastes generated are the assembly and the dismantling of the trade fair.The results indicate that the most common wastes generated are the protective plastic from carpets at the assembly stage and the carpet itself at the dismantling stage. The stand carpet is collected in bulk, while the carpet from the communal spaces is recycled. As the size of the fair increases, and with it the proportion of stands with customised design (or non-reusable stands), the quantity of wood and hazardous waste increases.  相似文献   
950.
This research focuses on the metallurgy and underground mining job positions in the historic mines of Almaden (Spain). We introduce a preventive methodology for hydrargyrism in work environments known by the name of Methodology for Operational Units Action Levels for Health Indicators (MUONAIS). The methodology allows critical levels to be established using environmental and clinical–biological indicators. The prevention plan concentrated on 15 job positions in the metallurgy department that employed more than 100 workers between the years 1986 and 1997. The development of this preventive methodology managed to keep workers’ mercury levels below 60 μg/l in blood and 200 μg/l in urine, values that present no negative effects on human health. MUONAIS has proven very effective in protecting workers’ health. During this period, some cases of micro-mercurialism were detected, yet were completely reversible, allowing us to affirm that the terrible disease of hydrargyrism was totally eradicated.  相似文献   
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