52 research outputs found

    Morphodynamics, sedimentary and anthropogenic influences in the San Vicente de la Barquera estuary (North coast of Spain)

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    The estuary of San Vicente de la Barquera (Cantabria, Spain) occupies two fluvial valleys that have incised into soft sedimentary rocks (Lower Mesozoic) and are controlled by inactive faults. These two estuary subsystems, the Escudo (main valley) and Gandarilla, share outer estuarine zones, i.e., a sandy bay and an estuary-mouth complex. The complexity of the system lies in the presence of a confining barrier formed by an aeolian dune/ beach system that is currently enclosed by a jetty, which has allowed the dune progradation over the past 50 years. Furthermore, connected to the inner inlet in the sand bay there is a flood-tidal delta, the most important morphosedimentary and dynamic unit. This unit exhibits a heart shape caused by the wide range of flows in this estuarine zone and channelizes the flows and sediments into the estuary, primarily during rising and high tides. In particular, the counter-clockwise surficial rotation due to the Coriolis effect is essential to the development of sand shoals, spill-over lobes, sand waves and megaripples. The presence of estuarine beaches into the bay is common in many Cantabrian estuaries, even culminating in small dune fields, in this case due to anthropogenic influences. This paper explains the impact on the estuary of human occupation and port management, focussing on the dynamic and sedimentary distribution of a bar-barrier estuary and the changes produced in its distal part by the construction of the two jetties in the mouth

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    Gestión de playas y dunas en las costas de Asturias y Cantabria (NWEspaña)

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    Se refieren playas y campos dunares de Asturias y Cantabria, que han sido objeto de alteraciones antrópicas indirectas y directas, entre las que cabe reseñarse las actuaciones de regeneración específicas, como ejemplos más significativos de esta costa cantábrica. Las playas afectadas han sido muy escasas, entre las que se encuentran algunas similares al modelo urbano (San Lorenzo y Laredo), artificializadas en sus perímetros; otras fueron sometidas a regeneración arenosa de sedimentos diferentes a los originales (El Gayo y Arbeyal) y solamente en el caso de Salinas-El Espartal se respetaron las características sedimentológicas previas; finalmente, un número reducido de playas fueron de nueva creación (Poniente, El Camello y Urdiales). Los campos dunares han experimentado transformaciones mayores y más variadas, incluyendo la destrucción total numerosos casos. Solamente se han regenerado algunos campos o sectores de los mismos con prácticas que han supuesto la reconstrucción morfológica, revegetación con especies específicas, aislamiento de recintos, así como ubicación de accesos, pasarelas y miradores de madera: Salinas-El Espartal, Cuchía, Liencres, Somo, etc.Beaches and dune fields of the Asturias and Cantabria (Cantabrian coast) which were directly and indirectly anthropized detailing some regeneration solutions are described in this paper. Only few beaches were affected, with some examples of urban beaches (San Lorenzo and Laredo); other beaches were regenerated with alocthonuos sandy sediments to the original sands and the Salinas-El Espartal beach where sedimentologic and mineralogically characteristics were maintained; finally, few new beaches were created. Dune fields were extensive and differently transformed, even distroyed. Only some of them were regenerated, consisting in the morphologic dune reconstruction, revegetation of specific plants, isolated enclosures, and woody observatory and roads: Salinas-El Espartal, Cuerna, Liencres, Somo, etc

    Hydrodynamic controls of morpho-sedimentary evolution in a rock-bounded mesotidal estuary. Tina Menor (N Spain)

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    The Tina Menor estuary is a highly confined incised valley with advanced sedimentary infilling. The outstanding feature of this estuary is its longitudinal zonation, which forms four segments from the outer to the inner limit: Mouth complex, Bay, Tidal flats and Upper channel. The innermost part of the Bay and the Tidal Flats (semi-reclaimed areas) are broader estuarine zones, whereas the Mouth Complex and outermost Bay are confined by narrow rocky outcrops. This paper explains the dynamics and sedimentary distribution of a highly confined and singular estuary, detailing the fluvial-tidal controls on the variations in water mixing (QF/QT). This estuary is largely of salt wedge type and the dynamics are characterised by recording currents (speed and direction) in the water column during a tidal cycle in a spring tide; this process consists of the tidal waves propagation and their dissipation upstream hypo-synchronously and the mixing of fresh and saline waters. The morphology, dynamics and sedimentary distributions have been integrated to develop a conceptual model that demonstrates the circulation within the estuary. The sinuous geometry of the estuarine valley and the Coriolis Effect detected, play a fundamental role in determining the morphology and sedimentary distribution. Consequently, this study provides an adequate overview of this type of confined mesotidal estuary, quite common in the eastern Atlantic coast.The mrophology, dynamics and sedimentary distributions have been integrated to develop a conceptual model that demonstrates the circulation within the estuary. The sinous geometry of the estuarine valley and the Coriolis effect detected, play  a fundamental role in determining the morphology and sedimentary distribution. Consequently, this study provides an adequate overview of this type of confined mesotidal estuary, quite common in the eastern Atlantic coast.El estuario de Tina Menor es un valle encajado altamente confinado y sedimentariamente en un avanzado estado de colmatación. Se caracteriza por su zonación longitudinal en cuatro segmentos bien diferenciados desde su sector más externo hasta el límite interior: Complejo de Desembocadura, Bahía, Llanuras Mareales y Canal Superior. El interior de la Bahía y las Llanuras Mareales de carácter fangoso (zonas semi-reclamadas) son las más extensas, mientras que el Complejo de Desembocadura y la parte externa de la Bahía, están estrechamente confinadas por afloramientos rocosos. Este trabajo explica la distribución dinámica y sedimentaria de un estuario singular y altamente confinado, detallando los controles fluviales-mareales en la variación de las mezclas de agua (QF/QT). Este estuario es en gran parte del tipo de cuña salina y la dinámica fue caracterizada por las medidas de corrientes (velocidad y dirección) realizadas en la columna de agua durante un ciclo mareal en marea viva; este proceso consiste en la propagación de las ondas de marea y su disipación de aguas arriba hiposincrónicamente y la mezcla de aguas dulces y salinas. La morfología, dinámica y las distribuciones sedimentarias, se han integrado para desarrollar un modelo conceptual que demuestre la circulación dentro del estuario. La geometría sinuosa del valle estuarino y la detección del efecto de Coriolis, juegan un rol fundamental para determinar la distribución morfologica y sedimentaria. Consecuentemente, este estudio proporciona un visión adecuada de este tipo de estuarios mesomareales confinados, tan comunes en las costas atlánticas orientales

    Geomorphological evolution of the calcareous coastal cliffs in North Iberia (Asturias and Cantabria regions)

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    This paper presents an analysis of the main morphologies observed in the coastal cliffs of northern Spain (Asturias and Cantabria regions). The objective of this contribution is to establish a hypothesis on the origin and evolution of this rocky coast, as well as to present a detailed inventory, to characterise quantitatively and qualitatively singular morphologies and to highlight the geological heritage of this protected coast. The evolution process starts with the formation of an ancient coastal planation surface characterised by a flat morphology caused by regional mainly uplift and to relative sea level falls. Afterwards, wave erosion processes would have started eroding the cliff foot and simultaneously, karst activity produced some exokarst morphologies (sinkholes, karren, etc.) through stratification and fracturing network, while the underground drainage systems produced some caves and chasms. In the following step, corresponding to the last glaciation from the paleoclimatic point of view, sea level fall together with a deepening of the fluvial network caused the preservation of the existing caves and chasms and the generation of new ones at a lower level. On the other hand, dissolution processes on limestones created sinkholes in those areas characterised by alternating layers of limestones and marls, generating collapses. When the sea level reached the maximum height during the Holocene a new erosion cycle of the coastal cliffs began. As a consequence, new landforms and processes were produced, like bays, caves fillings, and intrusion of new sediments in small confined estuaries. In these areas, other types of morphologies associated with the last sea level rise can be observed, such as closed beaches, uncommon closed estuaries developed inside a sinkhole, blowholes produced by mixed wave action and widening of prevailing vertical pipes inside the limestones (including the second largest in the world), total or partial sedimentary filling of small confined estuaries, as well as a tombolo deposit. It is important to point out, that some sites described are included in the Spanish Inventory of Sites of Geological Interest (IELIG). Due to the evolution model here proposed, a portion of the coastal sector described are included in the Global Geosites Project

    Hydrodynamic controls of morpho-sedimentary evolution in a rockbounded mesotidal estuary. Tina Menor (N Spain)

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    The Tina Menor estuary is a highly confined incised valley with advanced sedimentary infilling. The outstanding feature of this estuary is its longitudinal zonation, which forms four segments from the outer to the inner limit: Mouth complex, Bay, Tidal flats and Upper channel. The innermost part of the Bay and the Tidal Flats (semi-reclaimed areas) are broader estuarine zones, whereas the Mouth Complex and outermost Bay are confined by narrow rocky outcrops. This paper explains the dynamics and sedimentary distribution of a highly confined and singular estuary, detailing the fluvial-tidal controls on the variations in water mixing (QF/QT). This estuary is largely of salt wedge type and the dynamics are characterised by recording currents (speed and direction) in the water column during a tidal cycle in a spring tide; this process consists of the tidal waves propagation and their dissipation upstream hypo-synchronously and the mixing of fresh and saline waters. The morphology, dynamics and sedimentary distributions have been integrated to develop a conceptual model that demonstrates the circulation within the estuary. The sinuous geometry of the estuarine valley and the Coriolis Effect detected, play a fundamental role in determining the morphology and sedimentary distribution. Consequently, this study provides an adequate overview of this type of confined mesotidal estuary, quite common in the eastern Atlantic coast.El estuario de Tina Menor es un valle encajado altamente confinado y sedimentariamente en un avanzado estado de colmatación. Se caracteriza por su zonación longitudinal en cuatro segmentos bien diferenciados desde su sector más externo hasta el límite interior: Complejo de Desembocadura, Bahía, Llanuras Mareales y Canal Superior. El interior de la Bahía y las Llanuras Mareales de carácter fangoso (zonas semi-reclamadas) son las más extensas, mientras que el Complejo de Desembocadura y la parte externa de la Bahía, están estrechamente confinadas por afloramientos rocosos. Este trabajo explica la distribución dinámica y sedimentaria de un estuario singular y altamente confinado, detallando los controles fluviales-mareales en la variación de las mezclas de agua (QF/QT). Este estuario es en gran parte del tipo de cuña salina y la dinámica fue caracterizada por las medidas de corrientes (velocidad y dirección) realizadas en la columna de agua durante un ciclo mareal en marea viva; este proceso consiste en la propagación de las ondas de marea y su disipación de aguas arriba hiposincrónicamente y la mezcla de aguas dulces y salinas. La morfología, dinámica y las distribuciones sedimentarias, se han integrado para desarrollar un modelo conceptual que demuestre la circulación dentro del estuario. La geometría sinuosa del valle estuarino y la detección del efecto de Coriolis, juegan un rol fundamental para determinar la distribución morfologica y sedimentaria. Consecuentemente, este estudio proporciona un visión adecuada de este tipo de estuarios mesomareales confinados, tan comunes en las costas atlánticas orientales

    Previous SARS-CoV-2 Infection Increases B.1.1.7 Cross-Neutralization by Vaccinated Individuals

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    With the spread of new variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), there is a need to assess the protection conferred by both previous infections and current vaccination. Here we tested the neutralizing activity of infected and/or vaccinated individuals against pseudoviruses expressing the spike of the original SARS-CoV-2 isolate Wuhan-Hu-1 (WH1), the D614G mutant and the B.1.1.7 variant. Our data show that parameters of natural infection (time from infection and nature of the infecting variant) determined cross-neutralization. Uninfected vaccinees showed a small reduction in neutralization against the B.1.1.7 variant compared to both the WH1 strain and the D614G mutant. Interestingly, upon vaccination, previously infected individuals developed more robust neutralizing responses against B.1.1.7, suggesting that vaccines can boost the neutralization breadth conferred by natural infection

    The Critical Turning Points Database : Concept, Methodology and Dataset of an International Transformative Social Innovation Comparison (TRANSIT Working Paper # 10, July 12th 2017)

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    [Abstract] This working paper presents the TRANSIT open-access online database on Critical Turning Points (CTP) in Transformative Social Innovation. It specifies the contents of the database, comprising qualitative accounts of more than 450 ‘critical’ episodes in the evolution of social innovation initiatives in 27 different countries. Providing the theoretical-methodological context to these data, the paper also describes the theoretical background of the CTP concept and the methodology though which the CTP accounts have been reconstructed through interviews with members of SI initiatives. The paper concludes with reflections on the open access CTP database as a knowledge infrastructure, discussing its significance in terms of mapping, dissemination and framing of social innovation.This project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 61316
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