982 resultados para environmental indicator


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We assessed the efficacy of three different forest intervention techniques, in terms of phytosociological and edaphic responses, that were implemented in 2007. In a farm where trees are planted and managed for cellulose production as well as set aside for environmental conservation, four stands were analysed: three of them were considered degraded and were managed using different intervention techniques (transposition, perch, and abandonment), and a fourth stand comprising pristine vegetation was considered a control (reference). Floristic and phytosociology data were collected in three 10 × 10 m plots established in each stand. Also, a total of 48 soil samples were collected to analyse physical and chemical attributes of the topsoil for the different stands. In terms of biodiversity, all the treatments showed significantly lower values when compared to the reference area. However, the soils in all the treatment and reference stands are similar in terms of physical and chemical attributes. Taking into account the specificities of each restoration technique, we verified that the integrated use of a set of management practices, constituted by the (1) abandonment of the area and (2) following a selective killing of the eucalyptus, is the most suitable and promising model to provide fast and effective restoration in terms of environmental indicators.

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La calidad ambiental se refiere a la contribución del ambiente al bienestar humano. Los usos del suelo de tipo peligroso en un ambiente urbano pueden afectar dicha calidad. En este trabajo, se analiza y evalúa la calidad ambiental urbana con respecto a los usos del suelo de tipo peligroso ubicados dentro del ejido urbano: depósitos de agroquímicos; silos; garajes de fumigadores terrestres; depósitos de garrafas y tubos de gas licuado; estaciones de servicio. La metodología propuesta para este estudio es la aplicación de Sistemas de Indicadores Ambientales bajo el modelo "Presión-Estado-Respuesta" (OCDE), con el fin de plantear y medir un índice de Calidad Ambiental. El objetivo final es identificar factores que se comportan como profundizadores o mitigadores del riesgo, medidos a través de indicadores de presión, estado y respuesta

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La calidad ambiental se refiere a la contribución del ambiente al bienestar humano. Los usos del suelo de tipo peligroso en un ambiente urbano pueden afectar dicha calidad. En este trabajo, se analiza y evalúa la calidad ambiental urbana con respecto a los usos del suelo de tipo peligroso ubicados dentro del ejido urbano: depósitos de agroquímicos; silos; garajes de fumigadores terrestres; depósitos de garrafas y tubos de gas licuado; estaciones de servicio. La metodología propuesta para este estudio es la aplicación de Sistemas de Indicadores Ambientales bajo el modelo "Presión-Estado-Respuesta" (OCDE), con el fin de plantear y medir un índice de Calidad Ambiental. El objetivo final es identificar factores que se comportan como profundizadores o mitigadores del riesgo, medidos a través de indicadores de presión, estado y respuesta

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La calidad ambiental se refiere a la contribución del ambiente al bienestar humano. Los usos del suelo de tipo peligroso en un ambiente urbano pueden afectar dicha calidad. En este trabajo, se analiza y evalúa la calidad ambiental urbana con respecto a los usos del suelo de tipo peligroso ubicados dentro del ejido urbano: depósitos de agroquímicos; silos; garajes de fumigadores terrestres; depósitos de garrafas y tubos de gas licuado; estaciones de servicio. La metodología propuesta para este estudio es la aplicación de Sistemas de Indicadores Ambientales bajo el modelo "Presión-Estado-Respuesta" (OCDE), con el fin de plantear y medir un índice de Calidad Ambiental. El objetivo final es identificar factores que se comportan como profundizadores o mitigadores del riesgo, medidos a través de indicadores de presión, estado y respuesta

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Physiognomic traits of plant leaves such as size, shape or margin are decisively affected by the prevailing environmental conditions of the plant habitat. On the other hand, if a relationship between environment and leaf physiognomy can be shown to exist, vegetation represents a proxy for environmental conditions. This study investigates the relationship between physiognomic traits of leaves from European hardwood vegetation and environmental parameters in order to create a calibration dataset based on high resolution grid cell data. The leaf data are obtained from synthetic chorologic floras, the environmental data comprise climatic and ecologic data. The high resolution of the data allows for a detailed analysis of the spatial dependencies between the investigated parameters. The comparison of environmental parameters and leaf physiognomic characters reveals a clear correlation between temperature related parameters (e.g. mean annual temperature or ground frost frequency) and the expression of leaf characters (e.g. the type of leaf margin or the base of the lamina). Precipitation related parameters (e.g. mean annual precipitation), however, show no correlation with the leaf physiognomic composition of the vegetation. On the basis of these results, transfer functions for several environmental parameters are calculated from the leaf physiognomic composition of the extant vegetation. In a next step, a cluster analysis is applied to the dataset in order to identify "leaf physiognomic communities". Several of these are distinguished, characterised and subsequently used for vegetation classification. Concerning the leaf physiognomic diversity there are precise differences between each of these "leaf physiognomic classes". There is a clear increase of leaf physiognomic diversity with increasing variability of the environmental parameters: Northern vegetation types are characterised by a more or less homogeneous leaf physiognomic composition whereas southern vegetation types like the Mediterranean vegetation show a considerable higher leaf physiognomic diversity. Finally, the transfer functions are used to estimate palaeo-environmental parameters of three fossil European leaf assemblages from Late Oligocene and Middle Miocene. The results are compared with results obtained from other palaeo-environmental reconstructing methods. The estimates based on a direct linear ordination seem to be the most realistic ones, as they are highly consistent with the Coexistence Approach.

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Physiognomic traits of plant leaves such as size, shape or margin are decisively affected by the prevailing environmental conditions of the plant habitat. On the other hand, if a relationship between environment and leaf physiognomy can be shown to exist, vegetation represents a proxy for environmental conditions. This study investigates the relationship between physiognomic traits of leaves from European hardwood vegetation and environmental parameters in order to create a calibration dataset based on high resolution grid cell data. The leaf data are obtained from synthetic chorologic floras, the environmental data comprise climatic and ecologic data. The high resolution of the data allows for a detailed analysis of the spatial dependencies between the investigated parameters. The comparison of environmental parameters and leaf physiognomic characters reveals a clear correlation between temperature related parameters (e.g. mean annual temperature or ground frost frequency) and the expression of leaf characters (e.g. the type of leaf margin or the base of the lamina). Precipitation related parameters (e.g. mean annual precipitation), however, show no correlation with the leaf physiognomic composition of the vegetation. On the basis of these results, transfer functions for several environmental parameters are calculated from the leaf physiognomic composition of the extant vegetation. In a next step, a cluster analysis is applied to the dataset in order to identify "leaf physiognomic communities". Several of these are distinguished, characterised and subsequently used for vegetation classification. Concerning the leaf physiognomic diversity there are precise differences between each of these "leaf physiognomic classes". There is a clear increase of leaf physiognomic diversity with increasing variability of the environmental parameters: Northern vegetation types are characterised by a more or less homogeneous leaf physiognomic composition whereas southern vegetation types like the Mediterranean vegetation show a considerable higher leaf physiognomic diversity. Finally, the transfer functions are used to estimate palaeo-environmental parameters of three fossil European leaf assemblages from Late Oligocene and Middle Miocene. The results are compared with results obtained from other palaeo-environmental reconstructing methods. The estimates based on a direct linear ordination seem to be the most realistic ones, as they are highly consistent with the Coexistence Approach.

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This work has as object the elaboration of social environmental indicator of disaster risk that are present in precarious areas of human occupation, related to intense environmental dynamic from the perspective of the studies about the subject in Geography. The District of Mãe Luiza in Natal, capital city of Rio Grande do Norte, was defined as the study area. The place was chosen because it presents –historically- several vulnerability conditions and exposure to disaster risk. After a local social environmental description, two indexes were elaborated: the Social Vulnerability Index (SVI or IVS in Portuguese), based on 17 (seventeen) variables arranged on a questionnaire addressed to the population nucleus of the district, on regular grid (systematic sampling), classified into 5 (five) levels of SV from the weighted average; and the Physical and Natural Exposure to the Mass Movements Index (EMMI or IEMM in Portuguese) which had 16 (sixteen) variables that feature conditions of exposure to the mass movements in the district with classified levels from the weighted average of 1 (one) to 5 (five). The relationship between these two results, specialized in the district map, produced the Social Environmental Vulnerability Index (SEVI or IVSA in Portuguese) of Mãe Luiza, also classified into 5 (five) levels, following the Boolean logic correlation for cartographic overlay with use of computer software ArcGIS v.9.3, being named as: Very Low; low; average; high; and Very High Environmental Vulnerability in District. The study is based on the methodology proposed by Guerra et al (2009) for EMMI and by Almeida (2010) for SVI. They were modified and adapted according to the local reality, producing a new methodology in this study area. It was concluded that the neighborhood has most of its area with High and Very High Socio-environmental vulnerability to disasters, defined seven (7) critical areas, with Very High IVSA, and hazards associated with mass movements or flooding. In the end, the main issues that were found, such as generating elements for proposing mitigation measures and/or the proposed interventions were enumerated, related to structural order of vulnerability factors: how low constructive pattern of households; poor urban drainage; Real Estate forsaken in landslide routes; infrastructure ready access roads and slope containment. And social: as a lack of education about environmental risk; income and education of residents; presence of persons with limited mobility and/or those with special needs. This reality highlights the need for urgent action applied to the resolution and/or reduction of these problems, which is focusing the end of this work.

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Polychlorinated biphenyls (PCBs) and substituted phenylamine antioxidants (SPAs) are two chemical groups that have been used in multiple Canadian industrial processes. Despite the production ban of PCBs in North America in 1977, they are still ubiquitous in the environment and in wildlife tissues. Previous studies of fish, amphibians, birds, and mammals have shown that PCBs are toxic and act as endocrine disruptors. In contrast, SPAs, specifically N-phenyl-1-naphthylamine (PANA), have received very little attention despite their current use in Canada and their expected environmental releases. The effects of PCB and PANA exposures in reptiles remain unknown thus, juvenile Chelydra serpentina were used in this thesis as a model vertebrate to fill in missing toxicity research gaps due to their importance as an environmental indicator. First, food pellets were spiked at an environmentally relevant concentration of the PCB mixture Aroclor 1254 (A1254) to model hepatic bioaccumulation (0.45 μg/g A1254 for 31 days) and depuration (clean food for 50 days) of PCBs in turtles. No significant differences in PCB concentrations were observed between the control and treated animals, suggesting that juvenile turtles exposed to environmentally relevant concentrations of PCBs can likely detoxify low concentrations of PCBs. Additionally, two dose-response experiments were performed using A1254 or PANA spiked food (0-12.7 μg/g and 0-3,446 μg/g, respectively) to determine hepatic toxicity and bioaccumulation in juvenile C. serpentina. An increase in hepatic cyp1a was observed when exposed to the highest dose of both chemicals: 1) for A1254, induction correlated to the significant increase in hepatic PCB congeners that are known to be metabolized by CYP1A; and 2) for PANA, induction suggested that CYP1A has a potential role in its detoxification. PCBs are known endocrine disruptors, but no significant changes were observed for both thyroid receptors (alpha and beta) or by estrogen and androgen receptors. This lack of response, also noted in the PANA exposure, suggests that C. serpentina is less sensitive to endocrine disruption than other vertebrates. Furthermore, the expression of genes involved in cellular stress was not altered in PCB and PANA exposed animals, supporting the resilience of turtles to oxidative stress. This is the first study to demonstrate the toxicity of PCBs and PANA in C. serpentina, demonstrating the turtle’s high tolerance to contamination.

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Attempts were made to quantify the environmental impacts of the basement walls of two commercial buildings in London. Four different retaining wall options were designed based on steel and concrete systems for each of the sites. It was considered that excavation would take place with the aid of a one or two anchors system. Evaluation of embodied energy (EE) and CO2 emissions for each of the wall designs and anchoring systems were compared. Results show that there are notable differences in EE between different wall designs. Using the averaged set of Embodied Energy Intensity (EEI) values, the use of recycled steel over virgin steel would reduce the EE of the wall significantly. The difference in anchor designs is relatively insignificant, and therefore the practicality of the design for the specific site should be the deciding factor for anchor types. Generally, the scale of environmental impacts due to constructions is large compared to other aspects in life as demonstrated with the comparisons to car emissions and household energy consumption. Copyright ASCE 2008.

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Environmental aspects have been acknowledged as an important issue in decision making at any field during the last two decades. There are several available methodologies able to assess the environmental burden, among which the Ecological Footprint has been widely used due to its easy-to-understand final indicator. However, its theoretical base has been target of some criticisms about the inadequate representation of the sustainability concept by its final indicator. In a parallel way, efforts have been made to use the theoretical strength of the Emergy Accounting to obtain an index similar to that supplied by the Ecological Footprint. Focusing on these aspects, this work assesses the support area (SA) index for Brazilian sugarcane and American corn crop through four different approaches: Embodied Energy Analysis (SA(EE)), Ecological Footprint (SA(EF)), Renewable Empower Density (SA(R)), and Emergy Net Primary Productivity (SA(NPP)). Results indicate that the load on environment varies accordingly to the methodology considered for its calculation, in which emergy approach showed the higher values. Focusing on crops comparison, the load by producing both crops are similar with an average of 0.04 ha obtained by SA(EE), 1.86 ha by SA(EF), 4.24 ha by SA(R), and 4.32 ha by SA(NPP). Discussion indicates that support area calculated using Emergy Accounting is more eligible to represent the load on the environment due to its global scale view. Nevertheless, each methodology has its contribution depending of the study objectives, but it is important to consider the real meaning and the scope of each one. (C) 2012 Elsevier Ltd. All rights reserved.