948 resultados para open space, landscape artictecture, sustainability, landscape design


Relevância:

50.00% 50.00%

Publicador:

Resumo:

Actualmente en nuestro planeta producimos 1.300 millones de toneladas de residuos urbanos al año. Si los extendemos sobre la superficie de un cuadrado de lado 100 m (una hectárea) alcanzarían una altura de 146 km. ¿Cuál es el origen de nuestros residuos? ¿A dónde va esta basura? ¿Cómo nos afecta? ¿Tiene alguna utilidad? Se trata de un problema antiguo que, en los últimos tiempos, ha adquirido una nueva dimensión por el tipo y la cantidad de residuos generados. Las primeras preocupaciones de la ciudad por ordenar estos problemas dieron lugar al establecimiento de espacios o lugares específicos para la acumulación de los residuos urbanos: los vertederos. Los desechos hoy se generan más rápidamente que los medios disponibles para reciclarlos o tratarlos. Los vertederos de residuos urbanos son y seguirán siendo, a corto y medio plazo, soluciones válidas por ser un método de gestión relativamente barato, sobre todo en los países en vías de desarrollo. Como consecuencia y necesidad de lo anterior, se plantea demostrar que la recuperación y la transformación de estos vertederos de residuos urbanos (lugares del deterioro), una vez abandonados, es posible y que además pueden dar lugar a nuevos espacios públicos estratégicos de la ciudad contemporánea. Son espacios de oportunidad, vacíos monumentales producto de una reactivación arquitectónica y paisajística realizada a partir de complejos procesos de ingeniería medioambiental. Pero las soluciones aplicadas a los vertederos de residuos urbanos desde mediados del siglo XX se han realizado exclusivamente desde la ingeniería para tratar de resolver cuestiones técnicas, un modelo agotado que ya no puede gestionar la magnitud que este problema ha alcanzado, haciéndose necesaria e inevitable la participación de la arquitectura para abrir nuevas líneas de investigación y de acción. En estos primeros compases del siglo XXI existe una “nueva” preocupación, un “nuevo” interés en los paradigmas de lo ecológico y de la sostenibilidad, también un interés filosófico (que igualmente otorga un nuevo valor al residuo como recurso), que dirigen su mirada hacia un concepto de paisaje abierto y diferente a modelos anteriores más estáticos, recuperando como punto de partida el ideal pintoresco. El landscape urbanism se consolida como una disciplina capaz de dar respuesta a lo natural y artificial simultáneamente, que sustituye a las herramientas tradicionales de la arquitectura para solucionar los problemas de la ciudad contemporánea, incorporando las infraestructuras de gran escala, como un vertedero de residuos urbanos, y los paisajes públicos que generan como el verdadero mecanismo de organización del urbanismo de hoy. No se trata solo de un modelo formal sino, lo que es más importante: de un modelo de procesos. Esta nueva preocupación permite abordar la cuestión del paisaje de manera amplia, sin restricciones, con un alto grado de flexibilidad en las nuevas propuestas que surgen como consecuencia de estos conceptos, si bien los esfuerzos, hasta la fecha, parecen haberse dirigido más hacia el fenómeno de lo estético, quedando todavía por explorar las consecuencias políticas, sociales, económicas y energéticas derivadas de los residuos. También las arquitectónicas. El proyecto del landscape urbanism se ocupa de la superficie horizontal, del plano del suelo. Desde siempre, la preparación de este plano para desarrollar cualquier actividad humana ha sido un gesto fundacional, un gesto propio necesario de toda arquitectura, que además ahora debe considerarlo como un medio o soporte biológicamente activo. En términos contemporáneos, el interés disciplinar radica en la continuidad y en la accesibilidad del suelo, diluyendo los límites; en que funcione a largo plazo, que se anticipe al cambio, a través de la flexibilidad y de la capacidad de negociación, y que sea público. La recuperación de un vertedero de residuos urbanos ofrece todas estas condiciones. Un breve recorrido por la historia revela los primeros ejemplos aislados de recuperación de estos lugares del deterioro, que han pasado por distintas fases en función de la cantidad y el tipo de los desechos producidos, evolucionando gracias a la tecnología y a una nueva mirada sobre el paisaje, hasta desarrollar una verdadera conciencia de lo ecológico (nacimiento de una ideología). El Monte Testaccio en Roma (siglos I-III d.C.) constituye un caso paradigmático y ejemplar de vertedero planificado a priori no solo como lugar en el que depositar los residuos, sino como lugar que será recuperado posteriormente y devuelto a la ciudad en forma de espacio público. Una topografía de desechos generada por acumulación, organizada y planificada durante tres siglos, que nos hace reflexionar sobre los temas de producción, consumo y proyecto arquitectónico. El Monte Testaccio revela una fuente de inspiración, un arquetipo de gestión sostenible de los recursos y del territorio. A través de la experiencia en la recuperación y transformación en espacios públicos de casos contemporáneos, como el antiguo vertedero de Valdemingómez en Madrid o el de El Garraf en Barcelona, se han analizado las técnicas y las soluciones empleadas para establecer nuevas herramientas de proyecto planteadas en clave de futuro, que revelan la importancia de los procesos frente a la forma, en los cuales intervienen muchos factores (tanto naturales como artificiales), entre ellos la vida y el tiempo de la materia viva acumulada. Son lugares para nuevas oportunidades y ejemplos de una nueva relación con la naturaleza. La reactivación de los vertederos de residuos, a través del proyecto, nos propone una nueva topografía construida en el tiempo, el suelo como soporte, como punto de encuentro de la naturaleza y los sistemas tecnológicos de la ciudad que posibilitan nuevos modos de vida y nuevas actividades. Los vertederos de residuos son inmensas topografías naturales surgidas de procesos artificiales, atalayas desde las que divisar un nuevo horizonte, un nuevo mundo, un nuevo futuro donde sea posible lograr la reversibilidad de nuestros actos del deterioro. Pero la voluntad de estas recuperaciones y transformaciones no consiste exclusivamente en su reintegración al paisaje, sino que han servido como muestra de las nuevas actitudes que la sociedad ha de emprender en relación a los temas medio ambientales. ABSTRACT Here on our planet we currently produce 1.3 billion tonnes of urban waste per year. If we were to spread this over a surface of 100m2 (one hectare), it would reach a height of 146km. What is the origin of this waste? Where does our refuse go? How does it affect us? Does it have any uses? We are dealing with an old problem which, in recent times, has taken on a new dimension due to the type of waste and the amount generated. Cities’ first concerns in resolving these problems gave rise to the establishment of areas or specific places for the accumulation of urban waste: landfills. These days, waste is generated more quickly than the available resources can recycle or process it. Urban waste landfills are and will continue to be, in the short and mid-term, valid solutions, given that they constitute a relatively cheap method for waste management, especially in developing countries. Consequently and necessarily, we plan to demonstrate that it is possible to recover and transform these urban waste landfills (areas of deterioration) once they have been abandoned and that they can give rise to new strategic public areas in contemporary cities. They are areas of opportunity, monumental vacancies produced by an architectural reactivation of the landscape, which is achieved using complex processes of environmental engineering. But the solutions applied to urban waste landfills throughout the 20th century have used engineering exclusively in the attempt to resolve the technical aspects. This is a worn-out model which can no longer handle the magnitude which the problem has attained and therefore, there is an inevitable need for the participation of architecture, which can open new lines of research and action. In these first steps into the 21st century, there is a “new” concern, a “new” interest in the paradigms of environmentalism and sustainability. There is also a philosophical interest (which assigns the new value of ‘resource’ to waste) and all is aimed towards the concept of an open landscape, unlike the previous, more static models, and the intention is to recover picturesque ideals as the starting point. Landscape urbanism has been established as a discipline capable of simultaneously responding to the natural and the artificial, replacing the traditional tools of architecture in order to resolve contemporary cities’ problems. It incorporates large scale infrastructures, such as urban waste landfills, and public landscapes which are generated as the true organisational mechanism of modern day urbanism. It is not merely a formal model, it is more important than that: it is a model of processes. This new concern allows us to address the matter of landscape in a broad way, without restrictions, and with a great degree of flexibility in the new proposals which come about as a consequence of these concepts. However, efforts to date seem to have been more directed at aesthetic aspects and we have yet to explore the political, social, economic and energetic consequences derived from waste – nor have we delved into the architectural consequences. The landscape urbanism project is involved with the horizontal surface, the ground plane. Traditionally, the preparation of this plane for the development of any human activity has been a foundational act, a necessary act of all architecture, but now this plane must be considered as a biologically active medium or support. In contemporary terms, the discipline’s interest lies in the continuity and accessibility of the land, diffusing the limits; in long term functionality; in the anticipation of change, via flexibility and the ability to negotiate; and in it being a public space. The recovery of an urban waste landfill offers all of these conditions. A brief look through history reveals the first isolated examples of recovery of these spaces of deterioration. They have gone through various phases based on the quantity and type of waste produced, they have evolved thanks to technology and a new outlook on the landscape, and a real environmental awareness has been developed (the birth of an ideology). Monte Testaccio in Rome (1st to 3rd Century AD) constitutes a paradigmatic and exemplary case of a landfill that was planned a priori not only as a place to deposit waste but also as a place that would be subsequently recovered and given back to the city in the form of a public space. This spoil mound, generated by organised and planned accumulation over three centuries, makes us reflect on the themes of production, consumption and architectural planning. Monte Testaccio reveals a source of inspiration, an archetype of the sustainable management of resources and land. Using our experience of contemporary cases of land recovery and its transformation into public spaces, such as the former Valdemingómez landfill in Madrid or the Garraf in Barcelona, we analysed the techniques and solutions used in order to establish new project tools. These are proposed with an eye on the future, seeing as they reveal the importance of the processes over the form and involve many factors (both natural and artificial), including the life and age of the accumulated living matter. They are places for new opportunities and examples of our new relationship with nature. The reactivation of landfills, via this project, is a proposal for a new topography built within time, using the ground as the support, as the meeting point between nature and the technological systems of the city which make it possible for new ways of life and new activities to come about. Landfills are immense natural topographical areas produced by artificial processes, watchtowers from which to discern a new horizon, a new world, a new future in which it will be possible to reverse our acts of deterioration. But the intention behind these recoveries and transformations does not only hope for landscape reintegration but it also hopes that they will also serve as a sign of the new attitudes that must be adopted by society with regard to environmental matters.

Relevância:

50.00% 50.00%

Publicador:

Resumo:

El legado de una época, una situación social y unos criterios arquitectónicos, aparecen recogidos en el conjunto de edificios y en la trama urbana, de los pueblos de colonización de La Bazana y Valuengo (Jerez de los Caballeros, Badajoz, 1954), proyectados por Alejandro de la Sota durante la etapa en la que trabajó de forma externa para el Instituto Nacional de Colonización (INC). Al inicio de esta investigación no se habían realizado análisis en profundidad ni valoraciones críticas de su arquitectura, ni eran objeto de estudio en los ambientes universitarios, siendo prácticamente desconocidos para el conjunto de la profesión, que solía tomar como referencia de esta etapa de la arquitectura de Alejandro de la Sota para el INC, el poblado de Esquivel, en Sevilla, profusamente publicitado. Aunque en los últimos tiempos se han elaborado tesis en las Escuelas de Arquitectura abordando el tema de la colonización agraria en España en la década de los 50, los poblados de colonización en Extremadura o la arquitectura de Alejandro de la Sota para el INC, la presente tesis se aleja de la visión global unificadora o biográfica, para centrarse en el estudio monográfico de un objeto arquitectónico singular. El trabajo pretende documentar, estudiar, analizar y poner en valor, estas obras enclavadas en la arquitectura española de la década de los 50, denominados por su propio autor como “pueblos todo de plazas”, donde la arquitectura surge como respuesta a una realidad territorial, social y cultural, y a unas estrictas imposiciones prefijadas, que se resuelven teniendo como punto de partida las condiciones materiales y culturales del lugar en el que se ubican, para concluir planteando interpretaciones y lecturas que incorporan la tradición, pero que trascienden a ella. La metodología empleada consiste en un trabajo de documentación y análisis del objeto arquitectónico en tres fases: proyecto, obra construida y estado actual. En cada una de las fases se realiza un trabajo de campo consistente en la recopilación de la documentación original y en la elaboración de una nueva documentación gráfica, en base a los estudios y análisis realizados. El cotejo entre los datos obtenidos de los proyectos, las obras inicialmente construidas y el estado actual, darán como resultado un material de análisis inédito, que junto con la bibliografía incluida en el trabajo y los anexos que contienen la documentación original recabada sobre las obras en los organismos e instituciones que la custodian, ofrecen una interpretación más precisa de la realidad arquitectónica de estos pueblos, dejando el estudio abierto a nuevas vías de investigación que profundicen en la hipótesis del espacio vacío como organizador y colonizador del paisaje. ABSTRACT The legacy of an age, a social situation and a group of architectural criteria, appears reflected in the group of buildings and the urban design of colonization villages La Bazana and Valuengo (Jerez de los Caballeros, Badajoz, 1954), designed by Alejandro de la Sota during the time that he was working externally to the National Institute of Colonization(INC). At the beginning of this investigation they had not been analyzed or critically evaluated in depth and not even were being studied in university circles and for this reason were practically unknown to the profession, who used as a reference of this architecture period of Alejandro de la Sota for the INC, the colonization village of Esquivel in Seville, widely publicized. Although recently some doctoral thesis have been elaborated in the Architecture Schools about the topic of rural colonization in Spain in the 50s, the colonization villages in Extremadura or the architecture by Alejandro de la Sota for the INC, this thesis wants to get away from unifying or biographical overview, in order to centre the study about a singular architectural object. The work expects to document, study, analyze and push the value of this architectural pieces nestled in the Spanish architecture of 50s,and that were named by their author as “squares-villages”, where the architecture appears like answer to a territorial, social and culture reality, and a strict program impositions by the INC, which are solved by the architect taking as a starting point the material and cultural conditions from the place where are situated, to conclude with a interpretations and readings which incorporate the tradition and transcend it. The methodology used consists in documenting and analyzing work about the architectonic object in three stages: project, building and present state. In every stage, we make a field work in order to compile the original documents and at the same time a new graphical documentation is developed with the studies and analysis that were made before. The information about the projects, the architecture built at the beginning of the process, and the current state were compared and achieved an unpublished material which together with the bibliography and original documents, collected in the organizations and institutions that guard them, offer a more accurate interpretation about the architectural reality of these villages, leaving the study open for a new research which could go into detail about the hypothesis of urban empty space as element for colonize and organize the landscape.

Relevância:

50.00% 50.00%

Publicador:

Resumo:

We introduce a computational method to optimize the in vitro evolution of proteins. Simulating evolution with a simple model that statistically describes the fitness landscape, we find that beneficial mutations tend to occur at amino acid positions that are tolerant to substitutions, in the limit of small libraries and low mutation rates. We transform this observation into a design strategy by applying mean-field theory to a structure-based computational model to calculate each residue's structural tolerance. Thermostabilizing and activity-increasing mutations accumulated during the experimental directed evolution of subtilisin E and T4 lysozyme are strongly directed to sites identified by using this computational approach. This method can be used to predict positions where mutations are likely to lead to improvement of specific protein properties.

Relevância:

50.00% 50.00%

Publicador:

Resumo:

The aim of the present study is to identify and evaluate the relationship between Woodpigeon (Columba palumbus, Linnaeus, 1758) density and different environmental gradients (thermotype, ombrotype, continentality and latitudinal), land use and landscape structure, using geographic information systems and multivariate modelling. Transects (n = 396) were developed to estimate the density of Woodpigeon in the Marina Baja (Alicante, Spain) from 2006 to 2008. The highestdensity for Woodpigeon was in September-October (1.28birds/10ha) and the lowest inFebruary-March (0.34birds/10ha). Moreover, there were more Woodpigeons in areas with a mesomediterranean thermotypethan in thermomediterranean or supramediterranean ones. There was greater densityinthe intermediate zones compared to thecoast and interior. The natural or cultural landscape had the highest Woodpigeon density (1.53birds/10ha), with both denseand clear pine forest values standing out. Therefore, it is very important to conserve these traditional landscapes with adequate management strategies in order to maintain, resident and transient Woodpigeon populations. These natural areas are open places where the Woodpigeons find food and detect the presence ofpredators. Thus, this study will enable more precise knowledge of the ecological factors (habitat variables) that intervene in the distribution of Woodpigeon populations and their density.

Relevância:

50.00% 50.00%

Publicador:

Resumo:

Some would argue that there is a need for the traditional lecture format to be rethought in favour of a more active approach. However, this must form part of a bipartite strategy, considered in conjunction with the layout of any new space to facilitate alternative learning and teaching methods. With this in mind, this paper begins to examine the impact of the learning environment on the student learning experience, specifically focusing on students studying on the Architectural Technology and Management programme at Ulster University. The aim of this study is two-fold: to increase understanding of the impact of learning space layout, by taking a student centered approach; and to gain an appreciation of how technology can impact upon the learning space. The study forms part of a wider project being undertaken at Ulster University known as the Learning Landscape Transition Project, exploring the relationship between learning, teaching and space layout. Data collection was both qualitative and quantitative, with use of a case study supported by a questionnaire based on attitudinal scaling. A focus group was also used to further analyse the key trends resulting from the questionnaire. The initial results suggest that the learning environment, and the technology within it, can not only play an important part in the overall learning experience of the student, but also assist with preparation for the working environment to be experienced in professional life.

Relevância:

50.00% 50.00%

Publicador:

Resumo:

This paper analyses the EU budgetary responses to the ‘refugee crisis’ in Europe. The European Commission has proposed several changes to the EU budget as well as the establishment of new funding instruments. The paper explores what the announced funding consists of, what role it plays in policy-making and what issues it generates. Throughout these budgetary responses the search for flexibility has been dominant, motivated by the need to respond more swiftly to humanitarian and operational needs. In addition, the paper argues that beyond implementation or management, the role of funding is also symbolic and communicative. In light of limited competences that are difficult to exercise, funding represents a powerful tool enabling the Commission to shape policy-making in times of crisis. At the same time, the dominant search for flexibility also challenges established funding rules and procedures. It has furthermore led to reduced space for democratic scrutiny by the European Parliament. More profoundly, EU funding for cooperation with third countries to prevent the inflow of refugees and asylum seekers has monetised questions over the responsibility for these individuals. As the EU–Turkey agreement shows, this has created a self-imposed dependence on third countries, with the risk of potentially insatiable demands for EU funding. This paper questions the proportionality and rule of law compliance of allocating funding for the implementation of this agreement. Moreover, it proposes that the Commission take steps to practically safeguard the humanitarian aid principles in the management structures of the new funding instruments, and it stresses the need for more scrutiny of the reconfigured funding landscape by the European Parliament and the European Court of Auditors.

Relevância:

50.00% 50.00%

Publicador:

Resumo:

Mode of access: Internet.

Relevância:

50.00% 50.00%

Publicador:

Resumo:

"March 1990."

Relevância:

50.00% 50.00%

Publicador:

Resumo:

Over the past 25 years, betting on sports in the United States has grown dramatically with the majority of wagers being placed in illicit markets. Only 1% of an estimated 500 billion dollar sports betting industry in the United States is done legally. With this much at stake, the incentives to alter the outcome of the games are high. Corrupt gamblers can “fix” the match by offering payments to players to “throw the game,” that is, to predetermine the outcome in exchange for a payment (match fixing). This paper addresses whether match fixing in college basketball can be detected and contained with the current policies. A mixed method design will be used to identify possible “triggers” in Nevada Casino betting line movements that might warrant an investigation of cheating in the games. If match fixing can be detected at acceptable levels of probability, then current federal prohibitive law on sports betting might no longer be appropriate. Additionally, a survey will be administered to bettors in Nevada to analyze perceptions of the game’s integrity, further eroding the logic of current law.

Relevância:

50.00% 50.00%

Publicador:

Resumo:

Habitat loss and fragmentation have been implicated as driving forces behind recent waves of extinction. The regional landscape where this study occurred is a mosaic of forest and grassland, and therefore provides an ideal system with which to investigate the implications of habitat patchiness for the distribution and ecology of organisms. Here I describe patterns of amphibian and reptile distribution among and within habitats at the study site, investigate associations between habitat and community structure, describe nested subset patterns on forest islands, and quantify the relationship between body size and density across ecological scales and taxonomic groups. ^ Species richness did not vary across habitats, between forest island isolation classes or between island edges and cores. In contrast, species composition varied at all three ecological scales, reflecting differences in the distribution of both forest and open-habitat affiliated species. Species composition was associated with multivariate habitat profiles, with differences occurring along the isolation gradient of forest islands rather than the area gradient. The relationship between species composition and habitat was stronger for amphibians than for reptiles, a pattern that may be ascribed to physiological differences between the two groups. Analysis of nested subset pattern of community structure indicated that species composition of islands is nested as a function of isolation. Four species whose distribution on forest islands seems to be dispersal-limited drive the relationship between nestedness and isolation. Although there were several examples of shifts in body size across spatial scales and taxonomic groups, body size was not associated with density as predicted by theory, which may reflect differences between real and habitat islands, or differential responses of poikilothermic vertebrates to changes in density relative to homeotherms. ^ Taken together, the strongest result to emerge from this research is the importance of isolation, rather than area, on community structure in this system. Much evidence suggested that different ecological groups of species show distinct patterns of distribution both within and among habitat types. This suggests that species distributions at this site are not the result of 'neutral' processes at the community level, but rather reflect fundamental differences in the ecology of component species. ^

Relevância:

50.00% 50.00%

Publicador:

Resumo:

The urban landscape of Yerevan has experienced tremendous changes since the collapse of the Soviet Union and Armenia’s independence in 1991. Domestic and foreign investments have poured into Yerevan’s building sector, converting many downtown neighborhoods into sleek modern districts that now cater to foreign investors, tourists, and the newly rich Armenian nationals. Large portions of the city’s green parks and other public spaces have been commercialized for private and exclusive use, creating zones that are accessible only to the affluent. In this dissertation I explore the rapidly transforming landscape of Yerevan and its connections to the development of contemporary Armenian national identity. This research was guided by principles of ethnographic inquiry, and I employed diverse methods, including document and archival research, structured and semi-structured interviews and content analysis of news media. I also used geographic information systems (GIS) and satellite images to represent and visualize the stark transformations of spaces in Yerevan. Informed by and contributing to three literatures—on the relationship between landscape and identity formation, on the construction of national identity, and on Soviet and post-Soviet cities—this dissertation investigates how messages about contemporary Armenian national identity are being expressed via the transforming landscape of Armenia’s national capital. In it I describe the ways in which abrupt transformations have resulted in the physical and symbolic eviction of residents, introducing fierce public debates about belonging and exclusion within the changing urban context. I demonstrate that the new additions to Yerevan’s landscape and the symbolic messages that they carry are hotly contested by many long-time residents, who struggle for inclusion of their opinions and interests in the process of re-imagining their national capital. This dissertation illustrates many of the trends that are apparent in post-Soviet and post-Socialist space, while at the same time exposing some unique characteristics of the Armenian case.

Relevância:

50.00% 50.00%

Publicador:

Resumo:

More than half of the original Everglades extent formed a patterned peat mosaic of elevated ridges, lower and more open sloughs, and tree islands aligned parallel to the dominant flow direction. This ecologically important landscape structure remained in a dynamic equilibrium for millennia prior to rapid degradation over the past century in response to human manipulation of the hydrologic system. Restoration of the patterned landscape structure is one of the primary objectives of the Everglades restoration effort. Recent research has revealed that three main drivers regulated feedbacks that initiated and maintained landscape structure: the spatial and temporal distribution of surface water depths, surface and subsurface flow, and phosphorus supply. Causes of recent degradation include but are not limited to perturbations to these historically important controls; shifts in mineral and sulfate supply may have also contributed to degradation. Restoring predrainage hydrologic conditions will likely preserve remaining landscape pattern structure, provided a sufficient supply of surface water with low nutrient and low total dissolved solids content exists to maintain a rainfall-driven water chemistry. However, because of hysteresis in landscape evolution trajectories, restoration of areas with a fully degraded landscape could require additional human intervention.

Relevância:

50.00% 50.00%

Publicador:

Resumo:

Requirements for space based monitoring of permafrost features had been already defined within the IGOS Cryosphere Theme Report at the start of the IPY in 2007 (IGOS, 2007). The WMO Polar Space Task Group (PSTG, http://www.wmo.int/pages/prog/sat/pstg_en.php) identified the need to review the requirements for permafrost monitoring and to update these requirements in 2013. Relevant surveys with focus on satellite data are already available from the ESA DUE Permafrost User requirements survey (2009), the United States National Research Council (2014) and the ESA - CliC - IPA - GTN -P workshop in February 2014. These reports have been reviewed and specific needs discussed within the community and a white paper submitted to the WMO PSTG. Acquisition requirements for monitoring of especially terrain changes (incl. rock glaciers and coastal erosion) and lakes (extent, ice properties etc.) with respect to current satellite missions have been specified. About 50 locations ('cold spots') where permafrost (Arctic and Antarctic) in situ monitoring has been taking place for many years or where field stations are currently established have been identified. These sites have been proposed to the WMO Polar Space Task Group as focus areas for future monitoring by high resolution satellite data. The specifications of these sites including meta-data on site instrumentation have been published as supplement to the white paper (Bartsch et al. 2014, doi:10.1594/PANGAEA.847003). The representativity of the 'cold spots' around the arctic has been in the following assessed based on a landscape units product which has been developed as part of the FP7 project PAGE21. The ESA DUE Permafrost service has been utilized to produce a pan-arctic database (25km, 2000-2014) comprising Mean Annual Surface Temperature, Annual and summer Amplitude of Surface Temperature, Mean Summer (July-August) Surface Temperature. Surface status (frozen/unfrozen) related products have been also derived from the ESA DUE Permafrost service. This includes the length of unfrozen period, first unfrozen day and first frozen day. In addition, SAR (ENVISAT ASAR GM) statistics as well as topographic parameters have been considered. The circumpolar datasets have been assessed for their redundancy in information content. 12 distinct units could be derived. The landscape units reveal similarities between North Slope Alaska and the region from the Yamal Peninsula to the Yenisei estuary. Northern Canada is characterized by the same landscape units like western Siberia. North-eastern Canada shows similarities to the Laptev coast region. This paper presents the result of this assessment and formulates recommendations for extensions of the in situ monitoring networks and categorizes the sites by satellite data requirements (specifically Sentinels) with respect to the landscape type and related processes.

Relevância:

50.00% 50.00%

Publicador:

Resumo:

There is persistent interest in understanding responses of passerine birds to habitat fragmentation, but research findings have been inconsistent and sometimes contradictory in conclusions about how birds respond to characteristics of sites they occupy, such as habitat patch size or edge density. We examined whether these inconsistencies could result from differences in the amount of habitat in the surrounding landscape, e.g., for woodland birds, the amount of tree cover in the surrounding landscape. We compared responses of 22 woodland bird species to proximate-scale tree cover in open landscapes versus wooded landscapes. Our main expectation was that woodland birds would tolerate less suitable sites (less tree cover at the site scale) in open environments where they had little choice–where little tree cover was available in the surrounding area. We compared responses using logistic regression coefficients and loess plots in open and wooded landscapes in eastern North Dakota, USA. Responses to proximate-scale tree cover were stronger, not weaker, as expected, in open landscapes. In some cases the sign of the response changed from positive to negative in contrasting landscapes. We draw two conclusions: First, observed responses to proximate habitat measures such as habitat extent or edge density cannot be interpreted reliably unless landscape context is specified. Second, birds appear more selective, not less so, where habitat is sparse. Habitat loss and fragmentation at the landscape scale are likely to reduce the usefulness of local habitat conservation, and regional drivers in land-use change can have important effects for site-scale habitat use.

Relevância:

50.00% 50.00%

Publicador:

Resumo:

Focusing on the UK, this article addresses key issues facing the international distribution industry arising from over-the-top digital distribution and the fragmentation of audiences and revenues. Building on the identification of these issues, it investigates the extent to which UK distribution has altered over a ten-year period, pinpointing continuities in the destination and type of sales alongside changes in the role and structure of the industry as UK-based distributors adapt to a changing UK broadcasting landscape and global production environment. At one level increasing US ownership of UK-based distributors and the arrival of OTT players like Netflix, highlight the tensions between the national orientations of UK broadcasters and the global aspirations of independent producers and distributors. At another level VOD has boosted international sales of UK drama. Although the full impact of SVOD on content and rights has yet to materialise, significant changes in the industry predate the arrival of SVOD.