979 resultados para Spatial dynamics


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El tema central se vincula con el Ordenamiento territorial y su correlato en herramientas y metodologías de intervención y gestión urbanas, desde una visión del saber ambiental. A partir de los conceptos categoriales de territorio, actores y ambiente se propone aportar, por un lado metodologías para la comprensión, explicación y análisis del territorio y sus lugares, por el otro mecanismos de gestión para una normativa basada en la inteligencia territorial. Desde estos conceptos se pretende entonces, realizar una vinculación conceptual y normativa para la gestión sustentable del territorio que logre salvar las diferencias entre el estatismo normativo y la dinámica socio-espacial. El área objeto de estudio, es el aquella denominada aquí Area de La Bajada. Así, para un abordaje integral y conceptual del territorio se trabaja desde lo metodológico con los métodos Territorii y Stlocus. Incluyendo mecanismos participativos, como talleres y encuestas que aporten a la comprensión del territorio real, pensado, legal, vivido y posible, propuestos por Territorii que estructura el proceso de lectura y comprensión del lugar. Por su parte el método Stlocus en su ensamble con Territorii permite indagar y analizar el lugar, desde el reconocimiento de patrones de ocupación del lugar, apropiación territorial y vocaciones. Conceptos que llevarán a incoporar a la normativa categorías y dimensiones de urbanístico-territoriales. Desde lo ambiental, se cree de gran importancia el desarrollo del riesgo (vulnerabilidad + amenazas) como concepto operativo para la obtención de dos objetivos: la inclusión de los actores a la dinámica de gestión y la operativización de acciones ambientales directas sobre el territorio. Finalmente, luego del proceso de comprensión y análisis iniciado se arriba a tres cuestiones fundamentales: los métodos propuestos son herramientas flexibles que aportan a la comprensión del territorio desde conceptos categoriales de espacio se torna fundamental, los actores pueden ser incluidos en esta indagación en cualquier etapa del proceso. Sin embargo, aquí aparece la terca línea fundamental: la participación y la gestión de territorios sustentables. Para ello es necesario iniciar un proceso de gobernanza que logre minimizar los impactos de los procesos distorsivos del mercado mediante un Estado proactivo que regule de manera inclusiva, para reducir al mínimo las diferentes dinámicas entre los cuerpos normativos, y su vinculación directa con el territorio deseado por todos los ciudadanos a través de una normativa urbana con inteligencia territorial

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The spatial and temporal dynamics of seagrasses have been well studied at the leaf to patch scales, however, the link to large spatial extent landscape and population dynamics is still unresolved in seagrass ecology. Traditional remote sensing approaches have lacked the temporal resolution and consistency to appropriately address this issue. This study uses two high temporal resolution time-series of thematic seagrass cover maps to examine the spatial and temporal dynamics of seagrass at both an inter- and intra-annual time scales, one of the first globally to do so at this scale. Previous work by the authors developed an object-based approach to map seagrass cover level distribution from a long term archive of Landsat TM and ETM+ images on the Eastern Banks (~200 km**2), Moreton Bay, Australia. In this work a range of trend and time-series analysis methods are demonstrated for a time-series of 23 annual maps from 1988 to 2010 and a time-series of 16 monthly maps during 2008-2010. Significant new insight was presented regarding the inter- and intra-annual dynamics of seagrass persistence over time, seagrass cover level variability, seagrass cover level trajectory, and change in area of seagrass and cover levels over time. Overall we found that there was no significant decline in total seagrass area on the Eastern Banks, but there was a significant decline in seagrass cover level condition. A case study of two smaller communities within the Eastern Banks that experienced a decline in both overall seagrass area and condition are examined in detail, highlighting possible differences in environmental and process drivers. We demonstrate how trend and time-series analysis enabled seagrass distribution to be appropriately assessed in context of its spatial and temporal history and provides the ability to not only quantify change, but also describe the type of change. We also demonstrate the potential use of time-series analysis products to investigate seagrass growth and decline as well as the processes that drive it. This study demonstrates clear benefits over traditional seagrass mapping and monitoring approaches, and provides a proof of concept for the use of trend and time-series analysis of remotely sensed seagrass products to benefit current endeavours in seagrass ecology.

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El partido de Florencio Varela presenta configuraciones territoriales instituidas legalmente por la ordenanza de zonificación vigente, sobre la cual la interacción de situaciones demográficas, sociales, ocupacionales y productivas perfilan diversas espacialidades que fragmentan y trascienden los límites de la legalidad instituida.En este trabajo se da cuenta de los desplazamientos de esos bordes, haciendo foco en dos barrios del periurbano, cuya dinámica espacial es contrarrestada con las propias del ejido urbano y de la zona hortícola circundante. El análisis se aborda a partir del uso de la información y cartografía producida en el marco del Censo de población 2010, a nivel de radios y de los datos obtenidos a través de una encuesta hortícola realizada en el año 2011

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El partido de Florencio Varela presenta configuraciones territoriales instituidas legalmente por la ordenanza de zonificación vigente, sobre la cual la interacción de situaciones demográficas, sociales, ocupacionales y productivas perfilan diversas espacialidades que fragmentan y trascienden los límites de la legalidad instituida.En este trabajo se da cuenta de los desplazamientos de esos bordes, haciendo foco en dos barrios del periurbano, cuya dinámica espacial es contrarrestada con las propias del ejido urbano y de la zona hortícola circundante. El análisis se aborda a partir del uso de la información y cartografía producida en el marco del Censo de población 2010, a nivel de radios y de los datos obtenidos a través de una encuesta hortícola realizada en el año 2011

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Thermokarst lakes and basins are major components of ice-rich permafrost landscapes in East Siberian coastal lowlands and are regarded as indicators of regional climatic changes. We investigate the temporal and spatial dynamics of a 7.5 km**2, partly drained thermokarst basin (alas) using field investigations, remote sensing, Geographic Information Systems (GIS), and sediment analyses. The evolution of the thermokarst basin proceeded in two phases. The first phase started at the Pleistocene/Holocene transition (13 to 12 ka BP) with the initiation of a primary thermokarst lake on the Ice Complex surface. The lake expanded and persisted throughout the early Holocene before it drained abruptly about 5.7 ka BP, thereby creating a > 20 m deep alas with residual lakes. The second phase (5.7 ka BP to present) is characterized by alternating stages of lower and higher thermokarst intensity within the alas that were mainly controlled by local hydrological and relief conditions and accompanied by permafrost aggradation and degradation. It included diverse concurrent processes like lake expansion and stepwise drainage, polygonal ice-wedge growth, and the formation of drainage channels and a pingo, which occurred in different parts of the alas. This more dynamic thermokarst evolution resulted in a complex modern thermokarst landscape. However, on the regional scale, the changes during the second evolutionary phase after drainage of the initial thermokarst lakes were less intense than the early Holocene extensive thermokarst development in East Siberian coastal lowlands as a result of a significant regional change to warmer and wetter climate conditions.

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El partido de Florencio Varela presenta configuraciones territoriales instituidas legalmente por la ordenanza de zonificación vigente, sobre la cual la interacción de situaciones demográficas, sociales, ocupacionales y productivas perfilan diversas espacialidades que fragmentan y trascienden los límites de la legalidad instituida.En este trabajo se da cuenta de los desplazamientos de esos bordes, haciendo foco en dos barrios del periurbano, cuya dinámica espacial es contrarrestada con las propias del ejido urbano y de la zona hortícola circundante. El análisis se aborda a partir del uso de la información y cartografía producida en el marco del Censo de población 2010, a nivel de radios y de los datos obtenidos a través de una encuesta hortícola realizada en el año 2011

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Increasingly, large areas of native tropical forests are being transformed into a mosaic of human dominated land uses with scattered mature remnants and secondary forests. In general, at the end of the land clearing process, the landscape will have two forest components: a stable component of surviving mature forests, and a dynamic component of secondary forests of different ages. As the proportion of mature forests continues to decline, secondary forests play an increasing role in the conservation and restoration of biodiversity. This paper aims to predict and explain spatial and temporal patterns in the age of remnant mature and secondary forests in lowland Colombian landscapes. We analyse the age distributions of forest fragments, using detailed temporal land cover data derived from aerial photographs. Ordinal logistic regression analysis was applied to model the spatial dynamics of mature and secondary forest patches. In particular, the effect of soil fertility, accessibility and auto-correlated neighbourhood terms on forest age and time of isolation of remnant patches was assessed. In heavily transformed landscapes, forests account for approximately 8% of the total landscape area, of which three quarters are comprised of secondary forests. Secondary forest growth adjacent to mature forest patches increases mean patch size and core area, and therefore plays an important ecological role in maintaining landscape structure. The regression models show that forest age is positively associated with the amount of neighbouring forest, and negatively associated with the amount of neighbouring secondary vegetation, so the older the forest is the less secondary vegetation there is adjacent to it. Accessibility and soil fertility also have a negative but variable influence on the age of forest remnants. The probability of future clearing if current conditions hold is higher for regenerated than mature forests. The challenge of biodiversity conservation and restoration in dynamic and spatially heterogeneous landscape mosaics composed of mature and secondary forests is discussed. (c) 2004 Elsevier B.V. All rights reserved.

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The work presented here aims to make an analysis of the socio-spatial dynamics of associative supermarket chains and their importance in redefining the roles of small urban North Rio Grande cities. The theoretical approach gives priority to business as a city constituent whose understanding allows us to seize the new socio-spatial dynamics of small towns in the face of globalization and which caused changes in the scope of its commercial forms. In this sense, we understand that trade, as an essentially urban activity has a very specific characteristic, with respect to its ability to transform the content and meaning of places. Another important factor in the construction work was the context of changes in the capitalist production system with the advent of flexible production and the determinations of the economic globalization process that brought new ways of organizing trade. The empirical analysis of the research includes two associative supermarket chains, the “Rede 10” and the “Rede Seridó”, bringing together basic elements for understanding the genesis and evolution of this new organizational model of trade in small towns of the state, as well as allowed -In understand the main changes in this segment of commercial activity. The methodology we used literature in books and periodicals, collected mainly secondary data collection with the SEBRAE and the ABRAS and was still a field research where interviews were conducted forwarded along to the associative network managers to supermarkets, owners of associated facilities and with consumers of the surveyed networks .Finally, we conclude that the formation and expansion of associative supermarket chains in the context of small cities potiguares is essentially in a survival alternative traditional small traders, that sharing the associative principles albeit somewhat rigidly guided by the training cooperation networks can not only stay in the market , but to impose as a new agent in the capital of the reproduction process. Thus, the associative supermarket chains in the search for new spaces, particularly within small towns end up promoting new momentum in these cities providing different flows and interconnections with different places, giving new content and urban roles. By taking not only the condition of the place of living, but also the place to reproduce the capital, small towns offer their population better able to make purchases, thus avoiding the mandatory population shifts to other urban centers in order to meet their consumption needs.

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Long-distance movements of animals are an important driver of population spatial dynamics and determine the extent of overlap with area-focused human activities, such as fishing. Despite global concerns of declining shark populations, a major limitation in assessments of population trends or spatial management options is the lack of information on their long-term migratory behaviour. For a large marine predator, the tiger shark Galeocerdo cuvier, we show from individuals satellite-tracked for multiple years (up to 1101 days) that adult males undertake annually repeated, round-trip migrations of over 7,500 km in the northwest Atlantic. Notably, these migrations occurred between the highly disparate ecosystems of Caribbean coral reef regions in winter and high latitude oceanic areas in summer, with strong, repeated philopatry to specific overwintering insular habitat. Partial migration also occurred, with smaller, immature individuals displaying reduced migration propensity. Foraging may be a putative motivation for these oceanic migrations, with summer behaviour showing higher path tortuosity at the oceanic range extremes. The predictable migratory patterns and use of highly divergent ecosystems shown by male tiger sharks appear broadly similar to migrations seen in birds, reptiles and mammals, and highlight opportunities for dynamic spatial management and conservation measures of highly mobile sharks.

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Long-distance movements of animals are an important driver of population spatial dynamics and determine the extent of overlap with area-focused human activities, such as fishing. Despite global concerns of declining shark populations, a major limitation in assessments of population trends or spatial management options is the lack of information on their long-term migratory behaviour. For a large marine predator, the tiger shark Galeocerdo cuvier, we show from individuals satellite-tracked for multiple years (up to 1101 days) that adult males undertake annually repeated, round-trip migrations of over 7,500 km in the northwest Atlantic. Notably, these migrations occurred between the highly disparate ecosystems of Caribbean coral reef regions in winter and high latitude oceanic areas in summer, with strong, repeated philopatry to specific overwintering insular habitat. Partial migration also occurred, with smaller, immature individuals displaying reduced migration propensity. Foraging may be a putative motivation for these oceanic migrations, with summer behaviour showing higher path tortuosity at the oceanic range extremes. The predictable migratory patterns and use of highly divergent ecosystems shown by male tiger sharks appear broadly similar to migrations seen in birds, reptiles and mammals, and highlight opportunities for dynamic spatial management and conservation measures of highly mobile sharks.

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El artículo que se presenta tiene como propósito plantear hasta qué punto, durante los últimos años, con motivo de las políticas de seguridad, especialmente, de Andrés Pastrana (1998- 2002) y Álvaro Uribe (2002-2010), las guerrillas de las FARC y del ELN han experimentado un importante proceso de transformación. Lo anterior, por el cambio en las dinámicas espaciales del conflicto armado, que ha tendido a concentrarse en enclaves periféricos, de índole fronteriza, pero, sobre todo, caracterizados por una mayor dependencia de las finanzas provenientes del cultivo ilícito. Esto termina por desnaturalizar a las guerrillas y favorecer la posibilidad de entender las nuevas dinámicas de la violencia en Colombia así como las opciones reales de superación del conflicto.

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This dissertation is about the spatial configuration in Natal and processes in the Ponta Negra neighborhood today. Ponta Negra has undergone a number of critical social and spatial changes due to tourism development after the 1990s. It is of special interest to consider the intensification of real estate investment after 2000, when the new airport terminal, located in the neighboring municipality of Parnamirim, was in use. Ponta Negra is the place where most tourists go to, so attracting considerable public investments. New agents of transformation have produced change in the neighborhood as well. The present study aims at analysing the spatial processes in this part of the city. Here, the spatial configuration that resulted from extended real estate investments, both public and private, in recent years, is analysed in detail. The study identifies the multually differentiated, however internally homogenous areas. The concepts of production of space, contemporanean urban development and spatial dynamics are discussed. The research is based on document analysis and field work. Results were plotted to maps and tables. A detailed analysis of the spatial processes in the Ponta Negra neighborhood is undertaken as a conclusion, considering the contemporanean global scenario

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This paper addresses the construction and structuring of a technological niche – i.e. a protected space where promising but still underperforming technologies are stabilized and articulated with societal needs – and discusses the processes that influence niche development and may enable niche breakout. In theoretical terms the paper is grounded on the multi-level approach to sustainability transitions, and particularly on the niche literature. But it also attempts to address the limitations of this literature in what concerns the spatial dimension of niche development. It is argued that technological niches can transcend the narrow territorial boundaries to which they are often confined, and encompass communities and actions that span several spatial levels, without losing some territorial embeddedness. It is further proposed that these features shape the niche trajectory and, therefore, need to be explicitly considered by the niche theoretical framework. To address this problem the paper builds on and extends the socio-cognitive perspective to technology development, introducing a further dimension – space – which broadens the concept of technological niche and permits to better capture the complexity of niche behaviour. This extended framework is applied to the case of an emerging renewable energy technology – wave energy - which exhibits a particularly slow and non-linear development trajectory. The empirical analysis starts by examining how an “overall niche space” in wave energy was spatially constructed over time. Then it investigates in greater detail the niche development processes that took place in Portugal, a country that was among the pioneers in the field, and whose actors have been, from very early stages, engaged in the activities conducted at various spatial levels. Through this combined analysis, the paper seeks to understand whether and how niche development is shaped by processes taking place at different spatial levels. More specifically it investigates the interplay between territorial and relational elements in niche development, and how these different dynamics influence the performance of the niche processes and impact on the overall niche trajectory. The results confirm the niche multi-spatial dynamics, showing that it is shaped by the interplay between a niche relational space constructed by actors’ actions and interactions on/across levels, and the territorial effects introduced by these actors’ embeddedness in particular geographical and institutional settings. They contribute to a more precise understanding of the processes that can accelerate or slow down the trajectory of a technological niche. In addition, the results shed some light into the niche activities conducted in/originating from a specific territorial setting - Portugal - offering some insights into the behaviour of key actors and its implications for the positioning of the country in the emerging field, which can be relevant for the formulation of strategies and policies for this area.

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Spatial disease ecology is emerging as a new field that requires the integration of complementary approaches to address how the distribution and movements of hosts and parasites may condition the dynamics of their interactions. In this context, migration, the seasonal movement of animals to different zones of their distribution, is assumed to play a key role in the broad scale circulation of parasites and pathogens. Nevertheless, migration is not the only type of host movement that can influence the spatial ecology, evolution, and epidemiology of infectious diseases. Dispersal, the movement of individuals between the location where they were born or bred to a location where they breed, has attracted attention as another important type of movement for the spatial dynamics of infectious diseases. Host dispersal has notably been identified as a key factor for the evolution of host-parasite interactions as it implies gene flow among local host populations and thus can alter patterns of coevolution with infectious agents across spatial scales. However, not all movements between host populations lead to dispersal per se. One type of host movement that has been neglected, but that may also play a role in parasite spread is prospecting, i.e., movements targeted at selecting and securing new habitat for future breeding. Prospecting movements, which have been studied in detail in certain social species, could result in the dispersal of infectious agents among different host populations without necessarily involving host dispersal. In this article, we outline how these various types of host movements might influence the circulation of infectious disease agents and discuss methodological approaches that could be used to assess their importance. We specifically focus on examples from work on colonial seabirds, ticks, and tick-borne infectious agents. These are convenient biological models because they are strongly spatially structured and involve relatively simple communities of interacting species. Overall, this review emphasizes that explicit consideration of the behavioral and population ecology of hosts and parasites is required to disentangle the relative roles of different types of movement for the spread of infectious diseases.

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Dietary studies of marine species constitute an important key to improve the understanding of its biology and of its role in the ecosystem. Thus, prey-predator relationships structure and determine population dynamics and the trophic network at the ecosystem scale. Among the major study sites, the marine ecosystem is submitted to natural and anthropogenic constraints. In the North-Eastern part of the Atlantic Ocean, the Bay of Biscay is a large open area surrounded South by Spain and East by France. This bay is an historic place of intense fishery activities for which the main small pelagic species targeted are the pilchard, Sardina pilchardus and the anchovy, Engraulis encrasicolus. The aim of this work is to analyze the trophic ecology of these two small pelagic fish in spring in the Bay of Biscay. To do this, a first section is devoted to their prey composed by the mesozooplanktonic compartment, through a two-fold approach: the characterization of their spatio-temporal dynamics during the decade 2003-2013 and the measurement of their energetic content in spring. For this season, it appears that all prey types are not worth energetically and that the Bay of Biscay represents a mosaic of dietary habitat. Moreover, the spring mesozooplankton community presents a strong spatial structuration, a temporal evolution marked by a major change in abundance and a control by the microphytoplankton biomass. The second section of this work is relative to a methodological approach of the trophic ecology of S. pilchardus and E. encrasicolus. Three different trophic tracers have been used: isotopic ratios of carbon and nitrogen, parasitological fauna and mercury contamination levels. To improve the use of the first of these trophic tracers, an experimental approach has been conducted with S. pilchardus to determine a trophic discrimination factor. Finally, it appears that the use of these three trophic tracers has always been permitted to highlight a temporal variability of the relative trophic ecology of these fish. However, no spatial dynamics could be identified through these three trophic tracers.