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111.
During recent decades, the impact of industrial organisations on the environment has become clearly evident. It has also become more difficult to hide and more expensive. Globally, this has caused many enterprises to put all their efforts into seeking management instruments that allow them to reduce their negative impact on the environment as well as improving their economic efficiency. This environmental interest is either voluntary or forced by customers or by legal pressure. Environmental Management Systems (EMSs) are among the many tools that have appeared to fulfil that goal and that have drawn international researchers’ attention. The most popular system and the one most often used is the ISO 14001 standard.This paper examines empirically the influence that this certification exerts on the company’s pollutant emission policy. The analysis was carried out in four regions of Spain: Asturias, Cantabria, Galicia and Castilla-León and includes 126 industrial organisations. The goal of this paper is to investigate the behaviour of the companies according to their emissions policies once they have achieved the ISO 14001 certification. In the paper the Toxics Release Index of 56 certified companies is compared with the Index of 70 non-certified companies. Through a statistical analysis based on the Student’s t-test and the Mann–Whitney U test, it was concluded that ISO 14001 does not represent an environmental proactivity signal clearly enough to result in a reduction of the company’s environmental polluting index.  相似文献   
112.
Landfilling is a fundamental step in any waste management strategy, but it can constitute a hazard for the environment for a long time. The need to protect the environment from potential landfill emissions makes risk assessment a decision tool of extreme necessity. The heterogeneity of wastes and the complexity of physical, chemical and biological processes that occur in the body of a landfill need specific procedures in order to evaluate the groundwater risk for the environment. Given the complexity of the composition of landfill leachates, the exact contribution of each potential toxic substance cannot be known precisely. Some reference contaminants that constitute the hazard (toxicity) of leachate have to be found to perform the risk assessment. A preliminary ecotoxicological investigation with luminescent bacteria has been carried out on different leachates from traditional and sustainable landfills in order to rank the chemicals that better characterize the leachate (heavy metals, ammonia and dissolved organic content). The attention has been focused on ammonia because it is present in high concentration and can last for centuries and can seriously contaminate the groundwater. The results showed that the toxicity of the leachate might reliably depend on the ammonia concentration and that the leachate toxicity is considerably lower in sustainable landfills where the ammonia had been degraded. This has an important consequence because if the containment system fails (as usually occur within 30-50yr), the risk of groundwater contamination will be calculated easier only in terms of the probability that the ammonia concentration is higher than a reference concentration.  相似文献   
113.
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   
114.
Within the European intensive forest monitoring programme, the native vegetation on permanent Level II plots has been monitored for visible ozone injuries. The main purpose of the programme is to assess the potential risks for the forest vegetation and the natural ecosystems at the intensive monitoring plots. During the first years of the programme the surveys were qualitative, reporting only the number and the name of the symptomatic species in selected Light Exposed Sampling Site. In 2003 a new plot design was tested, based on the distribution of a number of miniplots along the edge of the forest, so as to obtain quantitative findings about the occurrence and distribution of the symptoms. The problems that still persist are related to: (i) the forest edge assessed for ozone symptoms may have a different floristic composition from the Level II plot itself; (ii) the anthropic pressure and the disturbances affecting the forest edge alters the floristic composition; (iii) the variability of the plant composition in the forest edge, which makes comparability difficult between different sites; and (iv) the evaluation of symptoms in several species that have not yet been experimentally tested. Further difficulties are due to the fact that symptoms observed in the field are often aspecific and cannot, therefore, be attributed solely to the phytotoxic action of ozone. To improve the effectiveness of the European programme, it is necessary: (i) to individualise and select common sensitive plant species for homogeneous ecological regions; (ii) to enhance experimental activities to test the sensitivity of a large number of plant species.  相似文献   
115.
Environmental issues have been at the center of society's concerns for a long time. Recently, this kind of concern is growing even more due to the damage caused to the environment by electrical and electronic product waste. Based on this same concern, this work aimed to analyze, through a literature review, the production and treatment of electronic waste in today's world, with an emphasis on Brazil and China. The articles reviewed point to an increase in the production of this type of waste, in both Brazil and China, and reveal that the current processes of treatment of electronic waste mostly aim to obtain profit through the recovery of precious metals such as copper. This paper concluded that although Brazil is one of the major producers of e‐waste, more than 90% of its e‐waste has not had a proper final destination. This deficiency in e‐waste treatment in Brazil is mainly due to financial factors and the lack of a robust educational policy focused on the environment. Thus, this work suggests the implementation of an effective educational policy aimed at environmental conservation, as well as investments in research on recycling methods in Brazil, especially on the use of e‐waste as an aggregate in the manufacture of concrete.  相似文献   
116.
The increase in population, the rapid economic growth and the rise in community living standards accelerate municipal solid waste (MSW) generation in developing cities. This problem is especially serious in Pudong New Area, Shanghai, China. The daily amount of MSW generated in Pudong was about 1.11 kg per person in 2006. According to the current population growth trend, the solid waste quantity generated will continue to increase with the city's development. In this paper, we describe a waste generation and composition analysis and provide a comprehensive review of municipal solid waste management (MSWM) in Pudong. Some of the important aspects of waste management, such as the current status of waste collection, transport and disposal in Pudong, will be illustrated. Also, the current situation will be evaluated, and its problems will be identified.  相似文献   
117.
This study reports a combined method using solid phase extraction (SPE), followed by solid phase microextraction (SPME) to concentrate different pesticides, including chlorinated, organophosphorus, triazines, pyretroids and chloroacetamides, present at trace levels in water samples. Identification and quantification was carried out by gas chromatography coupled to Mass Spectrometry (GC–MS). The optimized methodology showed LOQs at ng L?1 levels (ranging 0.2–3.5 ng L?1) in addition to acceptable precision and robustness (recoveries ranged 63–104%, RSD from 4% to 23%), presenting a novel method to reach trace levels, similar to that obtainable using EC detector, with structural confirmation by MS during the analysis of a wide range of environmental pollutants.This method was applied to the study of temporal and spatial distribution of pesticides in the Suquía River basin (Córdoba-Argentina). As expected, highest levels of agrochemicals were observed in areas with intensive agricultural practices, being atrazine (max. = 433.9 ng L?1), alpha-cypermetrine (max. = 121.7 ng L?1) and endosulfan sulfate (max. = 106.7 ng L?1) predominant. In urban areas, the prevalent pesticide was alpha-cypermethrine. These results draw attention to the need of pesticide monitoring programs in rivers, considering both urban and rural sections.  相似文献   
118.
119.

Purpose  

The purpose of this work is to contribute to the understanding of the photochemical air pollution analysing the levels and temporal variations of surface ozone in two rural areas situated in central-southern Spain.  相似文献   
120.
The Monterrey Metropolitan Area (MMA) has shown a high concentration of PM2.5 in its atmosphere since 2003. The contribution of possible sources of primary PM2.5 and its precursors is not known. In this paper we present the results of analyzing the chemical composition of sixty 24-hr samples of PM2.5 to determine possible sources of PM2.5 in the MMA. The samples were collected at the northeast and southeast of the MMA between November 22 and December 12, 2007, using low-volume devices. Teflon and quartz filters were used to collect the samples. The concentrations of 16 airborne trace elements were determined using x-ray fluorescence (XRF). Anions and cations were determined using ion chromatography. Organic carbon (OC) and elemental carbon (EC) were determined by thermal optical analysis. The results show that Ca had the maximum mean concentration of all elements studied, followed by S. Enrichment factors above 50 were calculated for S, Cl, Cu, Zn, Br and Pb. This indicates that these elements may come from anthropogenic sources. Overall, the major average components of PM2.5 were OC (41.7%), SO4(2-) (22.9%), EC (7.4%), crustal material (11.4%), and NO3- (12.6%), which altogether accounted for 96% of the mass. Statistically, we did not find any difference in SO4(2-) concentrations between the two sites. The fraction of secondary organic carbon was between 24% and 34%. The results of the factor analysis performed over 10 metals and OC and EC show that there are three main sources of PM2.5: crustal material and vehicle exhaust; industrial activity; and fuel oil burning. The results show that SO4(2-), OC, and crustal material are important components of PM2.5 in MMA. Further work is necessary to evaluate the proportion of secondary inorganic and organic aerosol in order to have a better understanding of the sources and precursors of aerosols in the MMA.  相似文献   
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