894 resultados para El Nino Current - Environmental aspects


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En caso de desplazamiento masivo, resulta imposible determinar inmediatamente de manera individual los temores de persecución de las personas que integran el grupo. Precisamente, ante la realidad desconsoladora de la promoción de una protección internacional exclusivamente aplicable a un tipo de refugiados casi inexistente, la cada vez menos frecuente determinación en grupo y prima facie de refugiados, la proliferación de estatutos subsidiarios, el aumento del desplazamiento interno y las restricciones que imponen los Estados por motivo de seguridad nacional u orden público, se consideró que un estudio sobre la protección de los flujos masivos podría facilitar la obtención de una visión general del estado actual de la protección temporal y de las obligaciones que se han desarrollado para hacer frente a tales contingencias. A partir del planteamiento inicial de los retos y obstáculos legales que este fenómeno ha planteado para los Estados receptores y para la evolución del Derecho internacional de los refugiados y de la inexistencia de un régimen jurídico internacional universal que regule la protección de los flujos masivos, se ha elaborado una construcción doctrinal y práctica sobre la protección de esta situación en el Derecho internacional, sistematizando los distintos elementos que se han ido incorporando a esta protección colectiva. Se ha analizado la protección de los flujos masivos con el ánimo de dotar de rasgos positivos a un concepto que ha sido considerado como un avance negativo en el ámbito de la protección internacional. Y es que la protección temporal no tiene por qué reducir estándares de protección ni tampoco sustituir a la protección internacional clásica, que es la de los refugiados.

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Els Sistemes d'Aiguamolls Construïts (SAC) de Flux Subsuperficial Horitzontal (FSH) és una tecnologia apropiada pel sanejament d'aigües residuals procedents de nuclis de població petits. No obstant els SAC de FSH són considerats una tecnologia natural, l'operació i manteniment d'aquestes depuradores és crucial per a garantir el seu correcte funcionament. Aquestes necessitats d'operació i manteniment varien entre depuradores segons (1) les característiques de la comunitat, (2) la configuració de la depuradora i el disseny del SAC de FSH i (3) les característiques del medi receptor. En aquest sentit, en aquesta tesi es presenta el desenvolupament d'un Sistema d'Ajuda a la Decisió (SAD) per a la definició de protocols d'operació i manteniment per a SAC de FSH tenint en compte els factors que causen variabilitat entre aquest tipus de depuradores (1, 2 i 3).

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The objectives of the thesis are identify in the current tourism landscape, tourist typologies which are capable of ensuring an adequate level of sustainability, ie that take into account the need to establish effective partnerships between major players in the touristic sector: 1. Looking for practical examples of more responsible tourism forms with resources. 2. Stressing the role played by ecotourism, this form of tourism according to the qual makes your holiday visitors relate more directly conscious of environmental and sociocultural present in the venue. 3. identifying actions to ensure the protection of the environment and the economic take off by traditionally depressed areas. 4. identifying objects aimed at boosting tourism consumption of a natural protected area interpreted as ideal as post-Fordist real space and identify profiles of tourists in protected areas. Also if tourism products linked to nature, culture and cuisine can help to revitalize the Ligurian coastal tourism 5. Checking if the regional system of protected areas has produced results in both environmental protection and endogenous development through tourism. 6. Quantifying the actual supply of the areas studied. 7. Checking if the three parks studied were identified and developed specific objects of tourist consumption.

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La calidad de energía eléctrica incluye la calidad del suministro y la calidad de la atención al cliente. La calidad del suministro a su vez se considera que la conforman dos partes, la forma de onda y la continuidad. En esta tesis se aborda la continuidad del suministro a través de la localización de faltas. Este problema se encuentra relativamente resuelto en los sistemas de transmisión, donde por las características homogéneas de la línea, la medición en ambos terminales y la disponibilidad de diversos equipos, se puede localizar el sitio de falta con una precisión relativamente alta. En sistemas de distribución, sin embargo, la localización de faltas es un problema complejo y aún no resuelto. La complejidad es debida principalmente a la presencia de conductores no homogéneos, cargas intermedias, derivaciones laterales y desbalances en el sistema y la carga. Además, normalmente, en estos sistemas sólo se cuenta con medidas en la subestación, y un modelo simplificado del circuito. Los principales esfuerzos en la localización han estado orientados al desarrollo de métodos que utilicen el fundamental de la tensión y de la corriente en la subestación, para estimar la reactancia hasta la falta. Como la obtención de la reactancia permite cuantificar la distancia al sitio de falta a partir del uso del modelo, el Método se considera Basado en el Modelo (MBM). Sin embargo, algunas de sus desventajas están asociadas a la necesidad de un buen modelo del sistema y a la posibilidad de localizar varios sitios donde puede haber ocurrido la falta, esto es, se puede presentar múltiple estimación del sitio de falta. Como aporte, en esta tesis se presenta un análisis y prueba comparativa entre varios de los MBM frecuentemente referenciados. Adicionalmente se complementa la solución con métodos que utilizan otro tipo de información, como la obtenida de las bases históricas de faltas con registros de tensión y corriente medidos en la subestación (no se limita solamente al fundamental). Como herramienta de extracción de información de estos registros, se utilizan y prueban dos técnicas de clasificación (LAMDA y SVM). Éstas relacionan las características obtenidas de la señal, con la zona bajo falta y se denominan en este documento como Métodos de Clasificación Basados en el Conocimiento (MCBC). La información que usan los MCBC se obtiene de los registros de tensión y de corriente medidos en la subestación de distribución, antes, durante y después de la falta. Los registros se procesan para obtener los siguientes descriptores: a) la magnitud de la variación de tensión ( dV ), b) la variación de la magnitud de corriente ( dI ), c) la variación de la potencia ( dS ), d) la reactancia de falta ( Xf ), e) la frecuencia del transitorio ( f ), y f) el valor propio máximo de la matriz de correlación de corrientes (Sv), cada uno de los cuales ha sido seleccionado por facilitar la localización de la falta. A partir de estos descriptores, se proponen diferentes conjuntos de entrenamiento y validación de los MCBC, y mediante una metodología que muestra la posibilidad de hallar relaciones entre estos conjuntos y las zonas en las cuales se presenta la falta, se seleccionan los de mejor comportamiento. Los resultados de aplicación, demuestran que con la combinación de los MCBC con los MBM, se puede reducir el problema de la múltiple estimación del sitio de falta. El MCBC determina la zona de falta, mientras que el MBM encuentra la distancia desde el punto de medida hasta la falta, la integración en un esquema híbrido toma las mejores características de cada método. En este documento, lo que se conoce como híbrido es la combinación de los MBM y los MCBC, de una forma complementaria. Finalmente y para comprobar los aportes de esta tesis, se propone y prueba un esquema de integración híbrida para localización de faltas en dos sistemas de distribución diferentes. Tanto los métodos que usan los parámetros del sistema y se fundamentan en la estimación de la impedancia (MBM), como aquellos que usan como información los descriptores y se fundamentan en técnicas de clasificación (MCBC), muestran su validez para resolver el problema de localización de faltas. Ambas metodologías propuestas tienen ventajas y desventajas, pero según la teoría de integración de métodos presentada, se alcanza una alta complementariedad, que permite la formulación de híbridos que mejoran los resultados, reduciendo o evitando el problema de la múltiple estimación de la falta.

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La autora sostiene que, dadas las condiciones usualmente impuestas por los países industrializados acreedores, el pago de la deuda externa es inviable para el Ecuador. Si se consideran aspectos económicos, sociales yambientales, se puede apreciar que el actual servicio de la deuda genera una balanza de pagos insostenible, deterioro de la capacidad productiva local. aumento de la precariedad del mercado laboral, incremento de la extrema pobreza y una presión insoportable sobre los recursos naturales. Mediante un análisis de ciertos indicadores selectos, la autora establece las relaciones existentes entre el ajuste para servir a la deuda, el deterioro de las condiciones de vida, el impacto en la agricultura y los recursos naturales y la dinámica de los procesos migratorios.

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The Bahrain International Circuit (BIC) is considered its one of the best international racing car track in terms of technical aspects and architectural quality. Two Formula 1 races have been hosted in the Kingdom of Bahrain, in 2004 and 2005, at BIC. The BIC had recently won the award of the best international racing car circuit. This paper highlights on the elements that contributed to the success of such project starting from the architectural aspects, construction, challenges, tendering process, risk management, the workforce, speed of the construction method, and future prospects for harnessing solar and wind energy for sustainable electrification and production of water for the circuit, i.e. making BIC green and environment-friendly international circuit.

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Pacific ocean temperature anomalies associated with the El Niño–Southern Oscillation (ENSO) modulate atmospheric convection and hence thunderstorm electrification. The generated current flows globally via the atmospheric electric circuit, which can be monitored anywhere on Earth. Atmospheric electricity measurements made at Shetland (in Scotland) display a mean global circuit response to ENSO that is characterized by strengthening during 'El Niño' conditions, and weakening during 'La Niña' conditions. Examining the hourly varying response indicates that a potential gradient (PG) increase around noon UT is likely to be associated with a change in atmospheric convection and resultant lightning activity over equatorial Africa and Eastern Asia. A secondary increase in PG just after midnight UT can be attributed to more shower clouds in the central Pacific ocean during an 'El Niño'.

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The destructive environmental and socio-economic impacts of the El Niño/Southern Oscillation1, 2 (ENSO) demand an improved understanding of how ENSO will change under future greenhouse warming. Robust projected changes in certain aspects of ENSO have been recently established3, 4, 5. However, there is as yet no consensus on the change in the magnitude of the associated sea surface temperature (SST) variability6, 7, 8, commonly used to represent ENSO amplitude1, 6, despite its strong effects on marine ecosystems and rainfall worldwide1, 2, 3, 4, 9. Here we show that the response of ENSO SST amplitude is time-varying, with an increasing trend in ENSO amplitude before 2040, followed by a decreasing trend thereafter. We attribute the previous lack of consensus to an expectation that the trend in ENSO amplitude over the entire twenty-first century is unidirectional, and to unrealistic model dynamics of tropical Pacific SST variability. We examine these complex processes across 22 models in the Coupled Model Intercomparison Project phase 5 (CMIP5) database10, forced under historical and greenhouse warming conditions. The nine most realistic models identified show a strong consensus on the time-varying response and reveal that the non-unidirectional behaviour is linked to a longitudinal difference in the surface warming rate across the Indo-Pacific basin. Our results carry important implications for climate projections and climate adaptation pathways.

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Goat fibre production is affected to a similar extent by genetic and environmental influences. Environmental influences include bio-geophysical factors (photoperiod, climate-herbage system and soil-plant trace nutrient composition), country of origin, nutrition factors (live weight, growth patterns) and management factors (farm, herd age and sex structure). Nutrition and management influences discussed include rate of stocking, energy nutrition, live weight change, parturition and management during shearing. The nutritional variation within and among years is the most important climatic factor influencing cashmere production, fibre diameter and fibre curvature (crimp). With productive cashmere goats, large responses to energy supplementation have been measured with optimum nutritional management. The effects and importance of management and hygiene during fibre harvesting (shearing) in producing quality fibre are emphasised.

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This thesis contends that government focus on policy implicitly defines community education as a means of overcoming barriers to government-initiated change, rather than as an input to governmental decision-making. The role of education is thus viewed as instrumentalist rather than as dialectical in nature. I argue that this role has been reinforced and driven by economic rationalism, as a mechanism related to scientific theory and practice. The thesis addresses the role of government in non-institutional community-based environmental education. Of interest is environmental education under the dominance of economic rationalism and as expressed in government-derived policy, in its own right, and as enacted in two government funded animal management projects. The main body of data, then, includes a review of some contemporary environmental policies and two case studies of 'policy in practice'. Chapter One provides an overview of environmentalism as it has emerged as part of the discourse of Western political systems. Recognised as part of this change is a move to environmentalism embued with the rhetoric of economic theory. The manifestation of this change can be seen in an emphasis on management for the natural environment's use as a resource for humans. Education under this arrangement is valued in terms of its ability to support initiatives that are perceived as economically viable and economically advantageous, maintaining centralised control of decision-making and serving the interests of those who profit from this arrangement. Government-derived environmental policies are presented in Chapter Two. They provide evidence of the conjoining of environment with economic rationalism and the adoption of a particular stance which is both utilitarian and instrumentalist. Emerging from this is an understanding of the limitations placed on environmental debates that do not respond to complex understandings of context and instead support and legitimate centralisation of decision-making and control. Chapter Three presents an argument for an historical approach to environmental education research to accommodate contextual dimensions, as well as scientific, economic and technical dimensions, of the subject under study. An historical approach to research, inclusive of biographical, intergenerational and geographical histories, goes some way to providing an understanding of current individual and collective responses to policy enactment within the two study sites. It also responds to the concealing of history which results from the reduction of environmental debates to economic terms. With this in mind, Chapters Four and Five provide two historical case studies of 'policy in practice'. Chapter Four traces the workings of a rabbit control project in the Sutton Grange district of Victoria and Chapter Five provides an account of a mouse plague project in the Wimmera and Mallee regions of Victoria. The Sutton Grange rabbit project is organised and controlled by district landholders while the Wimmera and Mallee mouse project is organised and controlled by representatives from a scientific organisation and a government agency. Considered in juxtaposition, the two case studies enable an analysis of two somewhat different expressions of the 'role of government'. Chapter Six investigates the competing processes of community participation in governmental decision-making and Australia's system of representative democracy, Despite a call for increased community participation, the majority of policies remain dominated by governmental rhetoric and ideology underpinned by a belief in impartiality. The primacy of economics is considered in terms of government and community interaction, with specific reference to the emergence of particular conceptual constructions, such as cost-benefit analysis, that support this dominance. Of specific importance to this thesis is the argument that economic theory is essentially anthropocentric and individualist and, thus, necessarily marginalises particular conceptions of environment that are non-anthropocentric and non-individualistic. Finally, Chapter Six examines two major interrelated tensions; those of central interests and community interests, and economic rationalism and environmentalist. Chapter Seven looks at examples of theories and practices that fall outside the rationality determined by scientistic knowledge. It is clear from the examination of environmental policy within this thesis that the role ascribed to environmental education is instrumentalist. The function of education is often to support, promote and implement policy and its advocated practices. It is also clear from the examination of policy and advocated processes that policy defines community education as a means of manifesting change as determined by policy, rather than as an input to governmental decision-making. The domination of scientific, economic and technocratic processes (and legitimation of processes) allows only for an instrumentalist approach to education from government. What is encouraged by government through the process of change is continuity rather than reform. It promotes change that will not disrupt the governing hegemony. Particular perspectives and practices, such as a critical approach to education, are omitted or considered only within the unquestioned rationale of the dominant worldview. Chapter Seven focuses on the consequence of government attention to policy which implicitly defines community education as a means of overcoming barriers to change, rather than as an input to governmental decision-making. Finally a list of recommendations is put forward as a starting point to reconstruct community-based environmental education. The role considered is one that responds to, and encourages engagement in, debates which expose disparate views, assumptions and positions. Community ideology must be challenged through the public practices of communication and understanding, decision-making, and action. Intervention is not on a level that encourages a preordinate outcome but, rather, what is encouraged is elaborate consideration of disparate views and rational opinions, and the exposure of assumptions and interests behind ideological positions.

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Pittosporum undulatum Vent. (Sweet Pittosporum) is a densely foliaged tall shrub or small tree, native to the wet forests of south east Australia, This species now functions as a serious environmental weed in a range of habitats in Australia and on other continents and islands throughout the temperate, sub-tropical and tropical zones. This study investigated some of the ecological causes and consequences of P. undulatum invasion across a range of habitat types in south east Australia. Key aspects of P. undulatum biology and ecology investigated in the current study include; patterns of morphological variation across the range of habitats occupied (as a measure of the species’ plasticity), dispersal ecology and seed germinability, population structure and spatial pattern, community relationships and the ecological impacts of invasion. Phenotypic plasticity is considerable in P. undulatum. No clear patterns of geographic variation emerged from a study of leaf morphological attributes across the current range of this species on mainland south east Australia. The pattern of morphological variation is particularly complex in Victoria, where the invasion of this species is most advanced. The species’ adaptability to a range of environments and environmental conditions will likely promote further range expansion. The abundant winter fruit crop produced by functionally female P. undulatum plants attracts a suite of generalist opportunistic frugivores, which feed on P. undulatum fruits and seeds at various stages of fruit dehiscence, thereby enhancing dispersal opportunities for this species. P. undulatum seed collected from natural and invasive populations, at two stages of fruit maturity and from the scats and pellets of dispersal agents, displayed high germinability. European Blackbirds and Pied Currawongs are implicated as the main avian dispersal agents of P undulatum in south east Australia. The broader ecological implications of developing relationships between invasive fleshy-fruited bird-dispersed plant species and adaptive frugivores are likely to be considerable. The distribution of P. undulatutn seedlings was significantly negatively correlated with adult conspecifics and significantly positively correlated with trees and shrubs of other genera. This pattern reflects the importance of both firugivorous dispersal agents and the species’ germination and establishment requirements, in shaping the contagious distribution pattern typical of this species. These analyses suggest that recruitment opportunities for conspecific seedlings are limited beneath the canopy of adult conspecifics. Densities of P. undulatum were on average, 2.7 times higher in invaded populations, compared to the natural populations sampled. A male-bias was evident in all populations and no relationships between reproductive activity and the density of seedlings and juveniles were evident. Invading populations of P. undulatum impose substantial changes on ecosystem-level properties and functions. Mean species richness and cover-abundance declined notably once P. undulatum cover-abundance exceeded 20% at the invaded sites and 60% at the natural sites sampled. The natural communities sampled displayed comparatively greater resilience to the competitive effects of P. undulatum, but community attributes were affected at high densities and cover-abundance of this species. The cover-abundance of herbs and grasses declined most substantially with increasing P. undulatum at invaded sites, whereas, at the natural sites sampled, the species’ structural analogues appeared to be most affected by increasing P. undulatum cover-abundance. This study has demonstrated that the ecological consequences of P. undulatum population expansion are substantial and contribute to changes in the composition and successional trajectory of affected communities. These processes ultimately lead to the loss and simplification of biodiversity values and the homogenisation of affected habitats. P. undulatum has the potential to emerge as one of south east Australia's most serious environmental weed species.

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The field of environmental education faces a process of continuous conceptual reconstruction that is underpinned by the complexity of the social and political changes occurring throughout the world as consequences of environmental crises and the different perspectives through which they are understood in different contexts. Thus there is a need to review and reflect on the meanings of environmental education, its theory and its practice. To address such issues the seminar, 'Environmental Education: from policy to practice', was held at King's College London in March 2001, under the sponsorship of the British Council and directed by Justin Dillon. The seminar brought together environmental educators from a broad spectrum--policy developers, researchers and practitioners--from Belize, Botswana, Brazil, Canada, Colombia, Cyprus, the Czech Republic, India, Mexico, the Russian Federation, Singapore, Swaziland, Sweden, the United Kingdom, the United States of America, Venezuela and Zimbabwe. During a thought-provoking six days the seminar discussed a diverse range of ideas about the current trends and future practices in environmental education. In this report we present our 'reading' and reflection on two major aspects of the discussion: the meanings of environmental education and education for sustainable development in different cultures and contexts. This we do from our own positions as academics working on environmental education in Latin American contexts.

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Understanding influences on children's physical activity and how these vary by activity and subgroup, such as age and sex of the child, is important for informing the development of effective and targeted interventions. Two cohort studies were conducted across socioeconomic areas of Melbourne, Australia, between 2001 and 2008 among a combined sample of more than 2,700 children aged 5-6 years and 10-12 years at baseline. Data were collected via surveys, and children wore the Actigraph accelerometer for 8 days. Five individual, 10 social, and 17 physical environmental factors were significantly associated with children's physical activity. Patterns of association varied according to the age and sex of the child and also according to the type of activity. These studies provide some insights into the various levels of influence on children's physical activity. More longitudinal and intervention research is needed to better understand the mechanisms of change in children's physical activity behaviour.

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Purpose: The purpose of this paper is to explore the state of environmental reporting by Indian companies on their web sites and also in their annual reports.
Design/methodology/approach: The web sites of the companies in the sample were visited to examine the accessibility and extent of environmental information disclosure on their web sites. The annual reports for 2003‐2004, as available on the companies' web sites were selected to investigate the extent of environmental information disclosure in these annual reports.
Findings: The paper finds that, although there are no regulations enforcing the disclosure of environmental information, most of the Indian companies have disclosed environmental information. These companies provided more environmental information on their web sites compared to the information provided in their annual reports.
Originality/value: This study contributes to the existing body of environmental reporting literature by focusing on the status of environmental reporting by companies of an emerging economy and also contributes to the existing body of environmental reporting literature by focusing on the accessibility of environmental information on web sites of respective companies.