630 resultados para Cordon littoral
Resumo:
Colombia has oceanic waters, catchment areas, like lakes, cienagas and swamps, water flows, like rivers, gorges and streams, small rivers and groundwater. The oceanic waters are the Caribbean Sea-1600 km and the Pacific Ocean-1300 km that comprise the north and west continental territory, respectively. Actually the Region of Darién, geographically bounded by the Carribean Sea to the north is becoming to be focused by studies due to use conflicts and disputes about water and a forest reserve on its territories. Considering its location, strategic at northwestern Colombia, frontier region with Central America, several dynamics are imposed. One of them is the implantation of a road system entitled Connecting Road of the Americas. This fact means the construction of an infra-structure that will cross a special zone formed by swamps and jungle known as The Darién Gap. Evidences of such interests are revealed by projects like the constructions of Turbo's Port in the Atlantic Ocean, Department of Antioquia and Tribugá's Port in the Pacific Ocean, Department of Choco, the mountain road and the coastal conection Colombia-Venezuela attending to the main intentions of the central region of the department (Metropolitan Area of Aburrá Valley-AMVA). Human settlements form a productive system, based on small and medium familiar agriculture's production, corresponding to the western portion and piedmont of Abibe's mountain at its antioquian portion, alluvial plan that forms the rivers on this area, the littoral zone that delimits the Carribean Sea, the Darién and Baudó Mountains and the gulf that receives, among other waters, the ones from Atrato and León, as well as the exodus process constitutes a forced exit resulting from actions of several armed groups. It can be identified intense historical, cultural, political and environmental relations, specially the last one associated with strategic ecosystems that are fundamental for the hydric regulation of the region, as well as food safety of the local inhabitants. Results from two researches (UPB, 2007 y 2010) reveals this quick transformation in the spatial re-configuration, demographical and economical indicators and the exacerbated fight for resources, damaging the extractive vocation in the Region. Path to commerce of illegalities (drugs, guns) and to implementation of the agroindustrial project for biofuel production, cooperation program that involves Venezuela, Brazil and Colombia. Appropriation modes allow the existence of strategies since global interests revealing a development logic that privileges the conception of an artificialized nature. Since the smallest portion of rural areas, specific modes of resources exploration are linked to imposed interests of transnational corporations. Disparate consequences are going deeper evidenced by social, technical and nature transformations, envisioning risks for the habitability's condition
Resumo:
Colombia has oceanic waters, catchment areas, like lakes, cienagas and swamps, water flows, like rivers, gorges and streams, small rivers and groundwater. The oceanic waters are the Caribbean Sea-1600 km and the Pacific Ocean-1300 km that comprise the north and west continental territory, respectively. Actually the Region of Darién, geographically bounded by the Carribean Sea to the north is becoming to be focused by studies due to use conflicts and disputes about water and a forest reserve on its territories. Considering its location, strategic at northwestern Colombia, frontier region with Central America, several dynamics are imposed. One of them is the implantation of a road system entitled Connecting Road of the Americas. This fact means the construction of an infra-structure that will cross a special zone formed by swamps and jungle known as The Darién Gap. Evidences of such interests are revealed by projects like the constructions of Turbo's Port in the Atlantic Ocean, Department of Antioquia and Tribugá's Port in the Pacific Ocean, Department of Choco, the mountain road and the coastal conection Colombia-Venezuela attending to the main intentions of the central region of the department (Metropolitan Area of Aburrá Valley-AMVA). Human settlements form a productive system, based on small and medium familiar agriculture's production, corresponding to the western portion and piedmont of Abibe's mountain at its antioquian portion, alluvial plan that forms the rivers on this area, the littoral zone that delimits the Carribean Sea, the Darién and Baudó Mountains and the gulf that receives, among other waters, the ones from Atrato and León, as well as the exodus process constitutes a forced exit resulting from actions of several armed groups. It can be identified intense historical, cultural, political and environmental relations, specially the last one associated with strategic ecosystems that are fundamental for the hydric regulation of the region, as well as food safety of the local inhabitants. Results from two researches (UPB, 2007 y 2010) reveals this quick transformation in the spatial re-configuration, demographical and economical indicators and the exacerbated fight for resources, damaging the extractive vocation in the Region. Path to commerce of illegalities (drugs, guns) and to implementation of the agroindustrial project for biofuel production, cooperation program that involves Venezuela, Brazil and Colombia. Appropriation modes allow the existence of strategies since global interests revealing a development logic that privileges the conception of an artificialized nature. Since the smallest portion of rural areas, specific modes of resources exploration are linked to imposed interests of transnational corporations. Disparate consequences are going deeper evidenced by social, technical and nature transformations, envisioning risks for the habitability's condition
Resumo:
Colombia has oceanic waters, catchment areas, like lakes, cienagas and swamps, water flows, like rivers, gorges and streams, small rivers and groundwater. The oceanic waters are the Caribbean Sea-1600 km and the Pacific Ocean-1300 km that comprise the north and west continental territory, respectively. Actually the Region of Darién, geographically bounded by the Carribean Sea to the north is becoming to be focused by studies due to use conflicts and disputes about water and a forest reserve on its territories. Considering its location, strategic at northwestern Colombia, frontier region with Central America, several dynamics are imposed. One of them is the implantation of a road system entitled Connecting Road of the Americas. This fact means the construction of an infra-structure that will cross a special zone formed by swamps and jungle known as The Darién Gap. Evidences of such interests are revealed by projects like the constructions of Turbo's Port in the Atlantic Ocean, Department of Antioquia and Tribugá's Port in the Pacific Ocean, Department of Choco, the mountain road and the coastal conection Colombia-Venezuela attending to the main intentions of the central region of the department (Metropolitan Area of Aburrá Valley-AMVA). Human settlements form a productive system, based on small and medium familiar agriculture's production, corresponding to the western portion and piedmont of Abibe's mountain at its antioquian portion, alluvial plan that forms the rivers on this area, the littoral zone that delimits the Carribean Sea, the Darién and Baudó Mountains and the gulf that receives, among other waters, the ones from Atrato and León, as well as the exodus process constitutes a forced exit resulting from actions of several armed groups. It can be identified intense historical, cultural, political and environmental relations, specially the last one associated with strategic ecosystems that are fundamental for the hydric regulation of the region, as well as food safety of the local inhabitants. Results from two researches (UPB, 2007 y 2010) reveals this quick transformation in the spatial re-configuration, demographical and economical indicators and the exacerbated fight for resources, damaging the extractive vocation in the Region. Path to commerce of illegalities (drugs, guns) and to implementation of the agroindustrial project for biofuel production, cooperation program that involves Venezuela, Brazil and Colombia. Appropriation modes allow the existence of strategies since global interests revealing a development logic that privileges the conception of an artificialized nature. Since the smallest portion of rural areas, specific modes of resources exploration are linked to imposed interests of transnational corporations. Disparate consequences are going deeper evidenced by social, technical and nature transformations, envisioning risks for the habitability's condition
Resumo:
Distribution, accumulation and diagenesis of surficial sediments in coastal and continental shelf systems follow complex chains of localized processes and form deposits of great spatial variability. Given the environmental and economic relevance of ocean margins, there is growing need for innovative geophysical exploration methods to characterize seafloor sediments by more than acoustic properties. A newly conceptualized benthic profiling and data processing approach based on controlled source electromagnetic (CSEM) imaging permits to coevally quantify the magnetic susceptibility and the electric conductivity of shallow marine deposits. The two physical properties differ fundamentally insofar as magnetic susceptibility mostly assesses solid particle characteristics such as terrigenous or iron mineral content, redox state and contamination level, while electric conductivity primarily relates to the fluid-filled pore space and detects salinity, porosity and grain-size variations. We develop and validate a layered half-space inversion algorithm for submarine multifrequency CSEM with concentric sensor configuration. Guided by results of modeling, we modified a commercial land CSEM sensor for submarine application, which was mounted into a nonconductive and nonmagnetic bottom-towed sled. This benthic EM profiler Neridis II achieves 25 soundings/second at 3-4 knots over continuous profiles of up to hundred kilometers. Magnetic susceptibility is determined from the 75 Hz in-phase response (90% signal originates from the top 50 cm), while electric conductivity is derived from the 5 kHz out-of-phase (quadrature) component (90% signal from the top 92 cm). Exemplary survey data from the north-west Iberian margin underline the excellent sensitivity, functionality and robustness of the system in littoral (~0-50 m) and neritic (~50-300 m) environments. Susceptibility vs. porosity cross-plots successfully identify known lithofacies units and their transitions. All presently available data indicate an eminent potential of CSEM profiling for assessing the complex distribution of shallow marine surficial sediments and for revealing climatic, hydrodynamic, diagenetic and anthropogenic factors governing their formation.
Resumo:
Taxonomic composition and structure of assemblages of the present-day benthic Foraminifera in the Kara Sea has been studied on the base of 37 samples of surface sediments. Three assemblages have been distinguished by composition of dominant species. The assemblage Cribrostomoides subglobosus-Tritaxis nana with prevalence of agglutinating forms, typical for abyssal areas of the World Ocean, occurs in brown oozes in the deep western part of the sea at depths 70-375 m under conditions of considerable bottom stratification. The assemblage Elphidium clavatum-Cassidulina reniforme consists predominantly of species with calcareous shells and is characterized by a wide range of species; this assemblage occurs in the eastern part of the sea at depths 30-90 m in a well-aerated area. Species typical for sublittoral areas of polar regions are dominant. The assemblage Elphidium clavatum-Haynesina orbiculare occupies the littoral estuarine part of the sea. This assemblage is poor in species and not abundant, and it occurs under influence of freshened water masses undersaturated with dissolved carbonaceous matter.
Resumo:
Three Spanish Antarctic research cruises (Ant-8611, Bentart-94 and Bentart-95) were carried out in the South Shetland Archipelago (Antarctic Peninsula) and Scotia Arc (South Orkney, South Sandwich and South Georgia archipelagos) on the continental shelf and upper slope (10-600 m depth). They have contributed to our knowledge about ascidian distribution and the zoogeographical relationships with the neighbouring areas and the other Subantarctic islands. The distribution of ascidian species suggests that the Scotia Arc is divided into two sectors, the South Orkney Archipelago, related to the Antarctic Province, and the South Georgia Archipelago (probably including the South Sandwich Archipelago), which is intermediate between the Antarctic Province and the Magellan region.