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 de transição (moderado). Salienta-se ainda que a urbanização, construção de estradas, pontes, açudes e atividades agropastoris, influenciaram para uma qualidade deficiente do setor 4 e muito ruim para o setor 5. O setor 2 também foi classificado como muito ruim, devido ao efeito do reservatório de Duas Bocas. Por fim, o método mostrou-se efetivo para a sua aplicação em regiões tropicais quentes e úmidas, incorporando o papel antrópico sobre os processos hidrogeomorfológicos.
Coastal retreat processes are usually associated with many anthropogenic actions, such as the regulation of river basins, the construction of hydraulic storm defence works in coastal areas and the ...building of housing on the beach. To all of this, we should also add the increase in sea levels due to the effect of climate change. The chosen area of study corresponds to the coastal area of the municipality of Guardamar del Segura, belonging to the Segura River Basin. The methodology applied in this study comprised the gathering of historical information, the extraction of data using GIS, the compiling of data using official organisations and the analysis of all these data from a geographical perspective. The obtained results show the chronology of the regulation works in the Segura Basin and their relationship with the reduction and negative trend in average ordinary flows (1940–2023) and the extraordinary, swelled flows recorded in the period 1994–2023. Furthermore, the coastlines from 1923 to 2023 were mapped, enabling us to determine the evolution of the coastline retreat processes experienced in the dune ridge of Guardamar del Segura and the increase in the frequency of impacts due to storms on Babilonia Beach. Finally, data on wind, waves and marine currents recorded at a gauging station were incorporated, enabling us to understand their impact on this coastal sector. The results obtained are discussed, and they indicate the need to incorporate data on sediment into the study in order to complete it. The conclusions reveal the existence of a relationship between all these anthropogenic elements in the beach erosion processes experienced in the village of Guardamar del Segura.
El curso medio-bajo del río Cinca ha sufrido importantes cambios en los últimos 90 años, tanto en la geomorfología de su cauce como en la vegetación que ocupa su Territorio Fluvial. En este estudio ...se han analizado los cambios observados entre las fotografías aéreas de nueve fechas distintas, desde 1927 a 2018, mediante fotointerpretación. Paralelamente, se ha analizado la hidrología, la extracción de gravas, la introducción de defensas y las roturaciones –entendidas como la puesta en cultivo por primera vez de tierras eriales o montes descuajados– como factores de influencia sobre el sistema fluvial. Los resultados obtenidos evidencian una gran reducción de la superficie ocupada por el canal activo en beneficio de la vegetación riparia y de otras cubiertas antropizadas. El cauce se ha simplificado, viéndose reducida su superficie activa y pasando de tener un patrón trenzado a otro divagante. Asimismo, la movilidad reciente es muy reducida y la lámina de agua ocupa la mayor parte del canal activo. En resumen, la reducción de la dinámica del amplio cauce de gravas del Cinca supone una notable pérdida de patrimonio natural en el marco hidrogeomorfológico de la Península Ibérica.
Arequipa is a semi-desert city located in southern Peru which depends on the Chili River as its only water source. During recent years, this city has increased its number of inhabitants significantly ...as a result of internal migratory flows and population growth. Because of this, the city has undergone a rapid urbanization process which has increased the urban areas near the river and caused the destruction of agricultural areas, as well as their native vegetation. This change in land use can be quantified through satellite image analysis across many years, but as noted, there are no studies on its impact on water yield (WY) in the urban section of the river. Now, by using the Integrated Valuation of Ecosystem Services and Compensation (InVEST) model, which allows the WY of the study area to be evaluated in millimeters and cubic meters by introducing a series of variables, such as precipitation, reference evapotranspiration and types of land use classes, among others, it is possible to determine that the WY from the study area was 1,743,414 m3 in 1984 and 1,323,792 m3 in 2022; the urban area is the type of land use with the highest increase with respect to its percentage contribution to the WY, going from 30.43% to 49.62% between 1984 and 2022, respectively. The increase in urban area mitigated the loss of total WY, explained by a higher percentage runoff rate, surface flow and drainage problems in the study area.
This study documents the impacts of engineering works on flood risk and channel dynamics of the maximum geomorphic flow reach of the Middle Ebro River (Spain) over the last ninety years. The map ...reveals how the construction of transversal transport lines and their ineffective design and maintenance has contributed to an elevated risk of flooding and channel avulsion at this location. In addition, the development of flood protection structures has restricted the natural dynamics of the river. These modifications have restricted the passage of flood waters, ultimately increasing flood hazards, by changing the area and depth of inundation and extending the flood hydrograph. The map allows for the interpretation of key processes, forecasting of flood hazards, and the evaluation of possible mitigating actions. These findings reconfirm that reducing space for the mobility of a river is not a good management solution and further aggravates the current situation.
The floods of 2015 and 2018 in the Middle Ebro River have led to a rethinking and updating of the forecasting and management systems. The improvements in the flow measurement systems applied in this ...type of extreme phenomena have led to questioning the values that were recorded in the past, officially changing the maximum flow rates of some historical floods. This has called for the need to update the knowledge/information of those recorded in the middle Ebro River, for example changing the return periods and making previous scientific studies obsolete. Updated data are applied, trying to re-characterize the floods of Ebro River since 1950, date in which the beginning of the “Anthropocene” is evident in the river management of the mainstream and its basin. At the same time, in the proposed risk management plans compliant with 2007/60/EC Directive, the structural measures are being replaced by more respectful and better adapted prevention systems for the river. The two processes interact and are essential for educating the population on risk, adopting preventive measures that are sustainable and consistent with the authentic (corrected) characteristics of the river and its floods. Thus, scientific knowledge has been consolidated as a tool to display corrected data, or, the river’s updated reality, and also to make the affected inhabitants aware of the need to follow new management protocols, focused on river resilience and social strategies.
Se analiza la crecida del río Turia en Teruel acaecida en junio de 1933. La prensa escrita
se hizo eco de una relevante crecida del río Turia con importantes efectos en las proximidades
de Teruel. A ...partir de esa evidencia, diversas fuentes documentales permiten averiguar
sus causas, estimar su volumen y conocer sus principales efectos. Esa información se coteja
con cálculos y fuentes cartográficas actuales para llegar a la conclusión de que se trata de una
crecida histórica muy destacada, a tener muy presente en la evaluación de los riesgos actuales
de inundaciones, y del enorme valor que la prensa escrita tiene para documentar crecidas
en etapas de finales del siglo XIX y primera parte del siglo XX.
Se presenta el proceso de trabajo para la elaboración de material didáctico a partir de herramientas de análisis geográfico. Estos materiales escolares están diseñados para trabajar en las aulas de ...Educación Secundaria la despoblación y el patrimonio cultural y natural en el mundo rural, como en este caso, en el “territorio mudéjar”. El objetivo es que el alumnado adquiera competencias que le permitan comprender y valorar este patrimonio, y pueda formular modelos y propuestas de desarrollo rural. Dichos materiales didácticos recogen contenidos que no están suficientemente incluidos en el currículo de Secundaria Obligatoria -despoblación, mudéjar, patrimonio natural, entorno- y que son importantes para el conocimiento y comprensión del territorio en el que vive el alumnado de esta etapa al que van dirigidos. Se han elaborado en la plataforma de ArcGIS Online y, por lo tanto, están alojados en la nube a la que se puede acceder desde cualquier dispositivo con conexión a internet. Se presentan en un hub agrupados en cuatro apartados: aplicaciones multimedia, mapas interactivos, visores de proyectos y videotutoriales. Son abiertos y adaptables a las necesidades e intereses tanto del alumnado como del profesorado facilitando, por otra parte, metodologías activas y adaptaciones de los materiales a partir de las bases de datos proporcionadas por organismos oficiales. En suma, es una propuesta de renovación metodológica a la vez que una apuesta por involucrar a los alumnos y alumnas de Territorio Mudéjar en la aportación de soluciones a los problemas que sus municipios tienen planteados.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Is geomorphology at the forefront of river management? The aims of this article are to explore potential answers to this question in terms of role, barriers, motivation and prospects for river ...management in the Anthropocene Era. We justify and execute our analysis, first through the growing interest in applied geomorphology and its role to improve river ecology and river policy design; second, by interviewing 24 specialists (researchers (i.e., biologists, ecologists, geomorphologists), engineers, river managers, planners) from different countries. We detected three barriers (academic, management and social) that prevent geomorphology from being more involved in river policy. We then propose three principles for living with rivers, considering geomorphology one of the key factors: (i) working across disciplinary frontiers, (ii) promoting integrated approaches, and (iii) improving fluvial education. Our conclusions look to rivers as natural and dynamic systems where geomorphological knowledge can improve the skills of engineers, ecologists and embrace a transdisciplinary approach. The new riverscape that we propose for the Anthropocene Era must be conceived using negotiation and discussion between an interconnected network of actors, regulators, scientists (sometimes), and natural and cultural values, where management objectives are raised and designed.
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