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311.
The development of methods for process analysis has contributed to the improvement of production systems. In this context, many models and methodologies have been established in the literature in order to evaluate environmental performance of industrial processes, since it has become an important issue for society. However, few of them analyze environmental impacts and related costs simultaneously. So, this work presents an integrated methodology to perform this evaluation, based on Life Cycle Assessment (LCA) and Activity-Based Costing (ABC) principles. The proposed methodology was applied in a metallurgical industry in Brazil. As result, it allowed to identify the production process stages which have critical environmental impacts and greatest contribution to increase environmental costs of the company.  相似文献   
312.
This paper describes the effects of drilling disturbance on the seafloor of the upper continental slope of the Campos Basin, Brazil, as a result of the project Environmental Monitoring of Offshore Drilling for Petroleum Exploration – MAPEM. Field sampling was carried out surrounding wells, operated by the company PETROBRAS, to compare sediment properties of the seafloor, including grain-size distribution, total organic carbon, and clay mineral composition, prior to drilling with samples obtained 3 and 22 months after drilling. The sampling grid used had 74 stations, 68 of which were located along 7 radials from the well up to a distance of 500 m. The other 6 stations were used as reference, and were located 2,500 m from the well. The results show no significant sedimentological variation in the area affected by drilling activity. The observed sedimentological changes include a fining of grain size, increase in total organic carbon, an increase in gibbsite, illite, and smectite, and a decrease in kaolinite after drilling took place.  相似文献   
313.
314.
The aim of this paper is to empirically assess the determinants of environmental technology investments in the Spanish industrial sectors with the help of panel data econometric techniques. The paper confirms the relevance of the stringency of environmental regulation to explain overall investment patterns in environmental technologies. These investments are also positively related to human and physical capital intensity and R&D intensity, and negatively related to the export intensity of sectors. Furthermore, the study shows that the determinants for investments are likely to differ between environmental technology types (i.e., end-of-pipe versus cleaner technologies).  相似文献   
315.
In this study we developed a dynamic growth model for Scots pine (Pinus sylvestris L.) plantations in Galicia (north-western Spain). The data used to develop the model were obtained from a network of permanent plots, of between 10 and 55-year-old, which the Unidade de Xestión Forestal Sostible (Sustainable Forest Management Unit) of the University of Santiago de Compostela has set up in pure plantations of this species of pine in its area of distribution in Galicia. In this model, the initial stand conditions at any point in time are defined by three state variables (number of trees per hectare, stand basal area and dominant height), and are used to estimate stand volume, classified by commercial classes, for a given projection age. The model uses three transition functions expressed as algebraic difference equations of the three corresponding state variables used to project the stand state at any point in time. In addition, the model incorporates a function for predicting initial stand basal area, which can be used to establish the starting point for the simulation. This alternative should only be used when the stand is not yet established or when no inventory data are available. Once the state variables are known for a specific moment, a distribution function is used to estimate the number of trees in each diameter class, by recovering the parameters of the Weibull function, using the moments of first and second order of the distribution (arithmetic mean diameter and variance, respectively). By using a generalized height–diameter function to estimate the height of the average tree in each diameter class, combined with a taper function that uses the above predicted diameter and height, it is then possible to estimate total or merchantable stand volume.  相似文献   
316.
Summary In order to determine the environmental problems as perceived by the community of Luján (Province of Buenos Aires, Argentina), a survey was carried out. The relationship between environmental perception and socio-economic level was also studied. The most important problems reported by the community were the floods, which occur when the Luján river overflows its banks, and the contamination of this river as it flows through Luján city. Deficiencies in the tourist infrastructure were also considered to be serious. The least perceived problem was that of industrial air pollution. Positive correlations between environmental perception, socio-economic standing and levels of instruction were observed.Claudia Feijoó is a Lecturer in Ecology at the National University of Luján. Her research interests are in environmental perception and ecology of rivers and polluted waters. Prof. Fernando Momo is Professor of Ecology at the same University. His research interests are focused on theoretical ecology and ecological modelling, especially as applied to aquatic ecology.  相似文献   
317.
本研究使用Landsat卫星数据来论证哥伦比亚-厄瓜多尔部分边界23年间(1973~1996)土地覆被变化的速度和格局.人类定居给这两个国家带来了大量毁林.变化的卫星检测分析表明,边界哥伦比亚一侧年毁林速度相对高得多.另外,哥伦比亚一侧森林覆被在研究期间几乎损失了43%,而在厄瓜多尔一侧只损失了22%.研究发现,在边界的任何一侧,都不存在单一的毁林驱动因素;但得出结论哥伦比亚一侧的毁林速度高可能是由于定居压力高、非法古柯种植加剧.卫星图像证明,在厄瓜多尔一侧,毁林格局反映出与石油勘探和开发有关的道路网络.  相似文献   
318.
In 1997, Brazil changed the regulatory framework of its oil and gas sector. After this change, a restrict subset of localities started to receive large amounts of oil rents. The goal of this paper is to evaluate whether such rents distributed under this law contributed to improving some social indicators relative to the national average in the eligible municipalities. We used a “difference-in-differences” measurement to compare changes in selected social indicators within affected Municipalities in the last two decades, taking the unaffected districts as control group. The Municipal data on social indicators were collected from three National Censuses, conducted in 1991, 2000 and 2010. Results show that royalties had a positive and statistically significant impact on household’s access to electric wiring, piped water and waste collection, as well as in the decrease of illiteracy rate. This means the eligible districts were able to improve some of their social indicators in the long-run.  相似文献   
319.
The performance of two mobile phase buffers, phosphate and TRIS, were compared for the speciation of four arsenic species: arsenate (As(V)), arsenite (As(III)), mono methylarsonic acid (MMA), and dimethyl arsinic acid (DMA) in drinking water, using ion-exchange chromatography inductivelycoupled plasma mass spectrometry (IEC-ICP-MS). The mobile phase containing TRIS acetate buffer ("TRIS") demonstrated superior perfomance in baseline separation of all four arsenic species and the internal standard. It is also applicable to high-throughput sample analysis as it minimized the frequency required to clean the sampling interface due to salt build-up when compared to the phosphate mobile phase. The method was evaluated for its precision, accuracy, linearity and detection limits. The method was successfully applied for the analysis of drinking water samples.  相似文献   
320.
Viña A  Echavarria FR  Rundquist DC 《Ambio》2004,33(3):118-125
This study uses Landsat satellite data to document the rates and patterns of land-cover change along a portion of the Colombia-Ecuador border during a 23-yr period (1973-1996). Human colonization has resulted in extensive deforestation in both countries. Satellite change detection analysis showed that the annual rates of deforestation were considerably higher for the Colombian side of the border. In addition, loss of forest cover on the Colombian side for the study period was almost 43%, while only 22% on the Ecuadorian side. The study found that there is no single factor driving deforestation on either side of the border, but concluded that the higher rates on the Colombian side may be due to higher colonization pressures and intensification of illegal coca cultivation. On the Ecuador side of the border the satellite images documented patterns of deforestation that reflected road networks associated with oil exploration and development.  相似文献   
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