Alterações hidrogeomorfológicas têm ocorrido ao longo de bacias hidrográficas com diferente magni... more Alterações hidrogeomorfológicas têm ocorrido ao longo de bacias hidrográficas com diferente magnitude e frequência. Em função disto, este trabalho tem como objetivo avaliar a qualidade hidrogeomorfológica do curso principal do rio Duas Bocas, na Região Metropolitana da Grande Vitória (ES/Brasil) para o ano de 2019, subsidiando o planejamento e gestão ambiental de cursos fluviais. A base cartográfica utilizada para realização do trabalho foram o ortofotomosaico de 2019 e o MDE com resolução espacial de 5mx5m; a drenagem foi modificada do IEMA, e, por fim, reconhecimento e verificação em campo. Para a classificação hidrogeomorfológica do curso fluvial é utilizado a proposta de Ollero et al. (2009). Com base nas informações cartográficas, o rio principal foi subdividido em cinco setores com extensão 5,66 km. Os resultados apontam que o setor de número 1, foi classificado hidrogeomorfologicamente como muito bom, devido as condições geoambientais. Quanto ao setor 3, foi classificado como...
Ce numéro de Sud-Ouest Européen déborde les frontières entre les états et s’intéresse à des « reg... more Ce numéro de Sud-Ouest Européen déborde les frontières entre les états et s’intéresse à des « regards croisés sur les fleuves Èbre et Garonne ». Il est le fruit d’une collaboration entre le département de géographie de l’université de Saragosse (par l’intermédiaire d’Alfredo Ollero) et le département de géographie de l’université Toulouse – Jean Jaurès (par l’intermédiaire de Philippe Valette)..
<p>Ephemeral streams are an important reality in the Mediterranean area, constituti... more <p>Ephemeral streams are an important reality in the Mediterranean area, constituting more than 50% of the channel network in the eastern region of the Iberian Peninsula. The northernmost cases are located in the semi-arid areas of the Ebro basin. Among the 592 cases registered (under the CCAMICEM project) in the Ebro basin, the Rambla de Cariñena stands out for its representativeness and dimensions.</p><p>With a basin area of 330 km<sup>2</sup>, it drains the northern piedmont of Sierra de Algairén (Iberian Mountain Range). It is a temporary river in its headwaters and upper course (Frasno River), which becomes ephemeral (Rambla) in its middle and lower courses, where it forms a large gravel bed river morphology, until it disappears without flowing into any river. In the past, there are references, as well as geomorphological evidence, that it had surface flow, but intensive vineyard agriculture and the global change recorded in the last 50 years have transformed it in ephemeral.</p><p>Recent years have showed relevant flash-floods, such as in the springs of 2008, 2015 and 2018. Its geomorphological dynamics is very interesting, with a highly sinuous meander, formation and destruction of gravel bars in each flood, and some incipient signs of incision. The Rambla de Cariñena constitutes a remarkable case for analyzing climate and global change in this type of fluvial course, as it has been worked on in the CCAMICEM project.</p><p>In this project, different characterization, assessment and monitoring works have been carried out in recent years, applying river survey techniques such as field reconnaissance, analysis and geomorphological mapping using drone flights, and radioelectric tomography to observe the depth of the alluvium. The evolutionary dynamics of the Rambla de Cariñena has also been explained through a multi-temporal analysis using aerial images and LiDAR PNOA data with a density of 0.5-4 points/m² to model the current channel. And the IHG hydrogeomorphological index has been applied to observe its impacts and assess its ecological status.</p><p>All this work has result in a database which is a base to follow the evolution of these streams in the future, as well as a pilot research for these river typologies in the Ebro basin and the identification of symptoms linked to climate change.</p><p>Key words: river survey techniques, flash flood, channel dynamics, IHG index, Rambla de Cariñena</p>
A diachronic geomorphological mapping has been done in some ephemeral rivers located in Ebro basi... more A diachronic geomorphological mapping has been done in some ephemeral rivers located in Ebro basin, Segura basin and Calabrian ephemeral rivers. We are presenting the specific results of six reaches distributed by the Ebro basin (Tudela, Reajo, Alpartir, Cariñena, Valcodo, Sosa and Seco). The first historical aerial image is that of the American Flight B of 1956-57, another of the mid 80’s, the last official ortophotography available (around 2017), and a specific flight with an unmanned aerial vehicle (UAV) done during the winter of 2019. An altimetry correction has been performed on the first two images.
Se han caracterizado y evaluado los procesos y resultados de la acción geomorfológica en la cuenc... more Se han caracterizado y evaluado los procesos y resultados de la acción geomorfológica en la cuenca del río Andalién para obtener una valoración del área, con su zonificación de acuerdo a su estado. Con ello se ha generado una visión integrada para su correcta planificación y manejo. En la cuenca se analiza también la acción antrópica (urbanización, actividades silvoagropecuarias y extractivas), que han causado un desequilibrio geomorfológico en las zonas aledañas al cauce principal y sus afluentes. Mediante la aplicación de un protocolo de caracterización y evaluación hidrogeomorfológica se han detectado tramos fluviales con alteraciones, asociados a espacios urbanos, para los que se plantean alternativas de restauración fluvial. Se ha validado así la utilidad del protocolo y se constatan las complejas interacciones y las posibilidades de integración territorial entre el medio urbano y el fluvial.
The classification of rivers based on geomorphological criteria played, in the past, a secondary ... more The classification of rivers based on geomorphological criteria played, in the past, a secondary role for management decision making, although in the last years they have experienced a shift from the scientific field to that of the technical. Currently, managers require the most simplified form of classifications in order to use them in plans and planning projects, management and restoration. On the one hand, this means that classifications should be directed toward simplifying the diversity of fluvial environments in a number of manageable types, and on the other hand, to apply to each geomorphic type a management model. In this study, we have developed a method of ''Geomorphic Classification of Rivers'' according to specific stream power variables and median grain size. The new method is dynamic (ability to readjust and gain robustness with the incorporation of new data) and predictive. We obtained six types directly from the method, although we added a seventh type (bedrock rivers) for its special singularity. Each geomorphic type presents concrete values of specific stream power and median grain size, which additionally involves a hydraulic geometry adjusted to terms of balance. The change from a geomorphic type to another would reflect a geomorphologic imbalance in the form of greater power and sediment size. Our results have been compared with six commonly used classifications (e.g., Rosgen Classification System or River Styles Framework). ''Geomorphic Classification of Rivers'' stands as a flexible tool that allows the development of a ''personalized'' geomorphic classification for rivers of the same geomorphological province. Through the temporary revision of various sites that act as control points, we can learn, should the case arise, the intensity and geomorphic change of the site. ''Geomorphic Classification of Rivers'' acts as an alert system for any geomorphologic disturbance. Its simple application and interpretation facilitate the implementation in the administrative environment, or its attachment to other commonly used classifications.
Revue géographique des Pyrénées et du Sud-Ouest 44 | 2017 Regards croisés sur les fleuves Èbre et... more Revue géographique des Pyrénées et du Sud-Ouest 44 | 2017 Regards croisés sur les fleuves Èbre et Garonne Une synthèse sur la restauration fluviale dans le bassin de l'Èbre River Restoration in Ebro Basin, a Synthesis Síntesis sobre la restauración fluvial en la cuenca del Ebro
El casco urbano de Monzón presenta un elevado riesgo deinundación por crecidas del río Sosa, que ... more El casco urbano de Monzón presenta un elevado riesgo deinundación por crecidas del río Sosa, que destaca por su comportamientohidrológico torrencial (flash flood). La crecida más reciente calificablecomo extraordinaria fue la de agosto de 2006, eligiéndose esteevento para modelizar la respuesta hidrológica de la cuenca ante precipitacionesintensas utilizando Sistemas de Información Geográfica (SIG).Así, se han utilizado datos de lluvia real en los modelos hidrológicos yse obtuvo en campo (método geomorfológico) el caudal máximo instantáneoque pudo registrarse en el núcleo urbano, estimándose en 236m3/s. Tras la crecida se realizó una cartografía de peligrosidad de inundaciones,calculando y representando las zonas inundables para crecidascon distintos periodos de retorno. Los modelos hidráulicos constatanun riesgo elevado, comprobándose que el Sosa puede desbordar la zona canalizada del tramo urbano para crecidas con periodos de retornosuperiores a los diez años.
Entre finales de marzo y primeros de abril de 2007 el río Ebro, el mayor colector mediterráneo de... more Entre finales de marzo y primeros de abril de 2007 el río Ebro, el mayor colector mediterráneo de la Península Ibérica, experimentó un complejo proceso de crecida. Este trabajo pretende analizar este proceso con detalle en sus causas meteorológicas y en sus consecuencias hidrológicas, siempre dentro del contexto de la gestión del riesgo de crecida en un entorno tan variado y tan intervenido como el de la Cuenca del Ebro. La originalidad de esta crecida radica en las tres puntas de caudal que se corresponden con las tres distintas fases atmosféricas: invernal, equinoccial y una transicional entre ambas. Las consecuencias en el Ebro medio abrieron el debate sobre las posibles medidas de gestión del riesgo.
Alterações hidrogeomorfológicas têm ocorrido ao longo de bacias hidrográficas com diferente magni... more Alterações hidrogeomorfológicas têm ocorrido ao longo de bacias hidrográficas com diferente magnitude e frequência. Em função disto, este trabalho tem como objetivo avaliar a qualidade hidrogeomorfológica do curso principal do rio Duas Bocas, na Região Metropolitana da Grande Vitória (ES/Brasil) para o ano de 2019, subsidiando o planejamento e gestão ambiental de cursos fluviais. A base cartográfica utilizada para realização do trabalho foram o ortofotomosaico de 2019 e o MDE com resolução espacial de 5mx5m; a drenagem foi modificada do IEMA, e, por fim, reconhecimento e verificação em campo. Para a classificação hidrogeomorfológica do curso fluvial é utilizado a proposta de Ollero et al. (2009). Com base nas informações cartográficas, o rio principal foi subdividido em cinco setores com extensão 5,66 km. Os resultados apontam que o setor de número 1, foi classificado hidrogeomorfologicamente como muito bom, devido as condições geoambientais. Quanto ao setor 3, foi classificado como...
Ce numéro de Sud-Ouest Européen déborde les frontières entre les états et s’intéresse à des « reg... more Ce numéro de Sud-Ouest Européen déborde les frontières entre les états et s’intéresse à des « regards croisés sur les fleuves Èbre et Garonne ». Il est le fruit d’une collaboration entre le département de géographie de l’université de Saragosse (par l’intermédiaire d’Alfredo Ollero) et le département de géographie de l’université Toulouse – Jean Jaurès (par l’intermédiaire de Philippe Valette)..
<p>Ephemeral streams are an important reality in the Mediterranean area, constituti... more <p>Ephemeral streams are an important reality in the Mediterranean area, constituting more than 50% of the channel network in the eastern region of the Iberian Peninsula. The northernmost cases are located in the semi-arid areas of the Ebro basin. Among the 592 cases registered (under the CCAMICEM project) in the Ebro basin, the Rambla de Cariñena stands out for its representativeness and dimensions.</p><p>With a basin area of 330 km<sup>2</sup>, it drains the northern piedmont of Sierra de Algairén (Iberian Mountain Range). It is a temporary river in its headwaters and upper course (Frasno River), which becomes ephemeral (Rambla) in its middle and lower courses, where it forms a large gravel bed river morphology, until it disappears without flowing into any river. In the past, there are references, as well as geomorphological evidence, that it had surface flow, but intensive vineyard agriculture and the global change recorded in the last 50 years have transformed it in ephemeral.</p><p>Recent years have showed relevant flash-floods, such as in the springs of 2008, 2015 and 2018. Its geomorphological dynamics is very interesting, with a highly sinuous meander, formation and destruction of gravel bars in each flood, and some incipient signs of incision. The Rambla de Cariñena constitutes a remarkable case for analyzing climate and global change in this type of fluvial course, as it has been worked on in the CCAMICEM project.</p><p>In this project, different characterization, assessment and monitoring works have been carried out in recent years, applying river survey techniques such as field reconnaissance, analysis and geomorphological mapping using drone flights, and radioelectric tomography to observe the depth of the alluvium. The evolutionary dynamics of the Rambla de Cariñena has also been explained through a multi-temporal analysis using aerial images and LiDAR PNOA data with a density of 0.5-4 points/m² to model the current channel. And the IHG hydrogeomorphological index has been applied to observe its impacts and assess its ecological status.</p><p>All this work has result in a database which is a base to follow the evolution of these streams in the future, as well as a pilot research for these river typologies in the Ebro basin and the identification of symptoms linked to climate change.</p><p>Key words: river survey techniques, flash flood, channel dynamics, IHG index, Rambla de Cariñena</p>
A diachronic geomorphological mapping has been done in some ephemeral rivers located in Ebro basi... more A diachronic geomorphological mapping has been done in some ephemeral rivers located in Ebro basin, Segura basin and Calabrian ephemeral rivers. We are presenting the specific results of six reaches distributed by the Ebro basin (Tudela, Reajo, Alpartir, Cariñena, Valcodo, Sosa and Seco). The first historical aerial image is that of the American Flight B of 1956-57, another of the mid 80’s, the last official ortophotography available (around 2017), and a specific flight with an unmanned aerial vehicle (UAV) done during the winter of 2019. An altimetry correction has been performed on the first two images.
Se han caracterizado y evaluado los procesos y resultados de la acción geomorfológica en la cuenc... more Se han caracterizado y evaluado los procesos y resultados de la acción geomorfológica en la cuenca del río Andalién para obtener una valoración del área, con su zonificación de acuerdo a su estado. Con ello se ha generado una visión integrada para su correcta planificación y manejo. En la cuenca se analiza también la acción antrópica (urbanización, actividades silvoagropecuarias y extractivas), que han causado un desequilibrio geomorfológico en las zonas aledañas al cauce principal y sus afluentes. Mediante la aplicación de un protocolo de caracterización y evaluación hidrogeomorfológica se han detectado tramos fluviales con alteraciones, asociados a espacios urbanos, para los que se plantean alternativas de restauración fluvial. Se ha validado así la utilidad del protocolo y se constatan las complejas interacciones y las posibilidades de integración territorial entre el medio urbano y el fluvial.
The classification of rivers based on geomorphological criteria played, in the past, a secondary ... more The classification of rivers based on geomorphological criteria played, in the past, a secondary role for management decision making, although in the last years they have experienced a shift from the scientific field to that of the technical. Currently, managers require the most simplified form of classifications in order to use them in plans and planning projects, management and restoration. On the one hand, this means that classifications should be directed toward simplifying the diversity of fluvial environments in a number of manageable types, and on the other hand, to apply to each geomorphic type a management model. In this study, we have developed a method of ''Geomorphic Classification of Rivers'' according to specific stream power variables and median grain size. The new method is dynamic (ability to readjust and gain robustness with the incorporation of new data) and predictive. We obtained six types directly from the method, although we added a seventh type (bedrock rivers) for its special singularity. Each geomorphic type presents concrete values of specific stream power and median grain size, which additionally involves a hydraulic geometry adjusted to terms of balance. The change from a geomorphic type to another would reflect a geomorphologic imbalance in the form of greater power and sediment size. Our results have been compared with six commonly used classifications (e.g., Rosgen Classification System or River Styles Framework). ''Geomorphic Classification of Rivers'' stands as a flexible tool that allows the development of a ''personalized'' geomorphic classification for rivers of the same geomorphological province. Through the temporary revision of various sites that act as control points, we can learn, should the case arise, the intensity and geomorphic change of the site. ''Geomorphic Classification of Rivers'' acts as an alert system for any geomorphologic disturbance. Its simple application and interpretation facilitate the implementation in the administrative environment, or its attachment to other commonly used classifications.
Revue géographique des Pyrénées et du Sud-Ouest 44 | 2017 Regards croisés sur les fleuves Èbre et... more Revue géographique des Pyrénées et du Sud-Ouest 44 | 2017 Regards croisés sur les fleuves Èbre et Garonne Une synthèse sur la restauration fluviale dans le bassin de l'Èbre River Restoration in Ebro Basin, a Synthesis Síntesis sobre la restauración fluvial en la cuenca del Ebro
El casco urbano de Monzón presenta un elevado riesgo deinundación por crecidas del río Sosa, que ... more El casco urbano de Monzón presenta un elevado riesgo deinundación por crecidas del río Sosa, que destaca por su comportamientohidrológico torrencial (flash flood). La crecida más reciente calificablecomo extraordinaria fue la de agosto de 2006, eligiéndose esteevento para modelizar la respuesta hidrológica de la cuenca ante precipitacionesintensas utilizando Sistemas de Información Geográfica (SIG).Así, se han utilizado datos de lluvia real en los modelos hidrológicos yse obtuvo en campo (método geomorfológico) el caudal máximo instantáneoque pudo registrarse en el núcleo urbano, estimándose en 236m3/s. Tras la crecida se realizó una cartografía de peligrosidad de inundaciones,calculando y representando las zonas inundables para crecidascon distintos periodos de retorno. Los modelos hidráulicos constatanun riesgo elevado, comprobándose que el Sosa puede desbordar la zona canalizada del tramo urbano para crecidas con periodos de retornosuperiores a los diez años.
Entre finales de marzo y primeros de abril de 2007 el río Ebro, el mayor colector mediterráneo de... more Entre finales de marzo y primeros de abril de 2007 el río Ebro, el mayor colector mediterráneo de la Península Ibérica, experimentó un complejo proceso de crecida. Este trabajo pretende analizar este proceso con detalle en sus causas meteorológicas y en sus consecuencias hidrológicas, siempre dentro del contexto de la gestión del riesgo de crecida en un entorno tan variado y tan intervenido como el de la Cuenca del Ebro. La originalidad de esta crecida radica en las tres puntas de caudal que se corresponden con las tres distintas fases atmosféricas: invernal, equinoccial y una transicional entre ambas. Las consecuencias en el Ebro medio abrieron el debate sobre las posibles medidas de gestión del riesgo.
In-stream wood is an essential component on stream ecology, river dynamics and channel restoratio... more In-stream wood is an essential component on stream ecology, river dynamics and channel restoration. In Spain public perception of wood in rivers is generally very negative. Wood is seen as a source of danger, and the common management strategy is to remove it from the channels, together with the elimination of sediments and living vegetation. Survey was conducted online, and in person, and we surveyed for the first time controlled groups of individuals living in areas affected and non-affected by flash floods in south-central Pyrenees, in the Ebro River and in the Spanish Central System. The perception of wood was assessed using a well-known questionnaire based on visual perception of stream and river scenes (20 colour photographs), according to aesthetics, naturalness, danger and need for improvement. In addition we requested information about personal opinion regarding river management. Preliminary results confirmed that channels with wood are considered more dangerous, and they a...
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