Dissertations / Theses on the topic 'Dee River'
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1
Cohen, P. M. "History of water management on the Welsh River Dee." Thesis, University of Manchester, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.546714.
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Speed, Mark. "The isotope hydrology of the River Dee, North East Scotland." Thesis, University of Aberdeen, 2011. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=182254.
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Identifying how the dominant runoff processes of sub-catchments integrate to determine hydrological responses at larger scales (> 1000 km2) remains a major challenge in hydrology. At these larger scales, major environmental differences such as climate, geology and land use may have increased influence on runoff dynamics. While process investigations at smaller scales (< 10km2) have been important in establishing the influence of topography and soils on runoff generation, more research at larger spatial scales is needed, since it is at such scales where important water management decisions are made in relation to applied problems such as floods and droughts. Tracers, such as stable isotopes of water, have proven utility as tools since they reflect the integration of processes at much smaller scales. In addition, geochemical tracers, such as alkalinity, help identify the geographical sources of runoff in larger catchments. This thesis focuses on their use to study catchment hydrological processes in the River Dee (~2,100 km2), NE Scotland, and to determine how these processes integrate at larger scales. Runoff from soil derived hydrological responsive pathways dominates during high flow facilitating a relatively rapid translation of precipitation isotope signatures into the channel network. Increased coverage of responsive soils resulted in reduced Mean Transit Time (MTT) estimates. High coverage of freely draining soils and certain landscape features often resulted in greater MTT estimates. Small scale heterogeneity appears to be averaged out at larger scales with MTTs indicating that the montane headwaters of the river are the dominant source of runoff. Transit Time Distributions (TTDs) suggest that catchment waters may have transit times of less than 2 weeks during high flows and greater than 10 years in summer baseflows.
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Moir, Hamish J. "The characterisation of Atlantic salmon spawning habitat in the River Dee and River Don catchments, north-east Scotland." Thesis, University of Aberdeen, 1999. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=186381.
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Wade, Andrew John. "Assessment and modelling of water chemistry in a large catchment, River Dee, NE Scotland." Thesis, University of Aberdeen, 1999. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU133417.
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This thesis describes the water chemistry of the River Dee and its tributaries, and the potential water chemistry changes that may occur under acid deposition and land use change scenarios. Historic water quality and flow records were collated and supplemented with new water chemistry data. These data were analysed in relation to catchment geography and river flow using both mathematical modelling and novel, GIS based techniques. This analysis established the importance of diffuse inputs and highlighted differences between upland and lowland regions in the catchment. In headwater streams, different geological types create hydrochemical source areas that strongly influence stream chemistry whilst in lowland tributaries, agricultural sources are particularly important. In the upland region most major ions were diluted as flows increased, further emphasizing the influence of deeper geological sources on baseflow chemistry, but showing soilwater controls on stormflow composition. The headwaters, which drain predominantly acid rocks, are presently oligotrophic but threatened by the impact of acid deposition and land use change (re-afforestation). In some of the lowland tributaries, increased NO3-N concentrations have resulted from more intensive land management. The potential impacts of acid deposition and land use change were simulated in both upland and lowland catchments by considering existing and new models within a Functional Unit Network. For upland regions this consisted of developing a new, two component hydrochemical mixing model to simulate the spatial and flow-related variations in streamwater acidity. The mixing model was based on End Member Mixing Analysis (EMMA), and site specific end members (alkalinity and Ca) could be predicted from emergent catchment characteristics (soil and land use) using linear regression.
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McDonald, Kenneth P. "Survival, home range, movements, habitat use, and feeding habits of reintroduced river otters in Ohio." Connect to resource, 1989. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1125079007.
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Dikdogmus, Halil. "RISER CONCEPTS FOR DEEP WATERS." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for marin teknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18528.
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Oil and gas exploration and production activities in deep and ultra deep waters in hostile environments necessitates the need to develop innovative riser systems capable of ensuring transfer of fluids from the seabed to a floating vessel and vice versa, with little or no issues with respect to influences of environmental loads and vessel motions.The design of the riser system must focus on different types of loading and load effects than for traditional water-depth. A variety of different riser concepts are proposed, both with respect to geometric shape and selection of materials.In the last few years, steel catenary risers have been a preferred riser solution for deep-water field developments due to its simple engineering concept, cost effective, flexibility in using different host platform and flexibility in geographical and environmental conditions. In this report, a case study considering a steel catenary riser operating in 1000 m water depth was conducted. The riser was subjected to extreme environmental conditions and static and dynamic response analyses were performed by the computer program RIFLEX.Last, parametric study is carried out to investigate the effects of parameter variation based on some parameters like current profiles, mesh density, wall thickness and so on. These parameters have significant effect on the structural response, especially in the touch down region.
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Olaya, Marín Esther Julia. "Ecological models at fish community and species level to support effective river restoration." Doctoral thesis, Universitat Politècnica de València, 2013. http://hdl.handle.net/10251/28853.
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RESUMEN
Los peces nativos son indicadores de la salud de los ecosistemas acuáticos, y se han
convertido en un elemento de calidad clave para evaluar el estado ecológico de los ríos. La
comprensión de los factores que afectan a las especies nativas de peces es importante para la
gestión y conservación de los ecosistemas acuáticos. El objetivo general de esta tesis es analizar
las relaciones entre variables biológicas y de hábitat (incluyendo la conectividad) a través de
una variedad de escalas espaciales en los ríos Mediterráneos, con el desarrollo de herramientas
de modelación para apoyar la toma de decisiones en la restauración de ríos.
Esta tesis se compone de cuatro artículos. El primero tiene como objetivos modelar la
relación entre un conjunto de variables ambientales y la riqueza de especies nativas (NFSR), y
evaluar la eficacia de potenciales acciones de restauración para mejorar la NFSR en la cuenca
del río Júcar. Para ello se aplicó un enfoque de modelación de red neuronal artificial (ANN),
utilizando en la fase de entrenamiento el algoritmo Levenberg-Marquardt. Se aplicó el método
de las derivadas parciales para determinar la importancia relativa de las variables ambientales.
Según los resultados, el modelo de ANN combina variables que describen la calidad de ribera,
la calidad del agua y el hábitat físico, y ayudó a identificar los principales factores que
condicionan el patrón de distribución de la NFSR en los ríos Mediterráneos. En la segunda parte
del estudio, el modelo fue utilizado para evaluar la eficacia de dos acciones de restauración en el
río Júcar: la eliminación de dos azudes abandonados, con el consiguiente incremento de la
proporción de corrientes. Estas simulaciones indican que la riqueza aumenta con el incremento
de la longitud libre de barreras artificiales y la proporción del mesohabitat de corriente, y
demostró la utilidad de las ANN como una poderosa herramienta para apoyar la toma de
decisiones en el manejo y restauración ecológica de los ríos Mediterráneos.
El segundo artículo tiene como objetivo determinar la importancia relativa de los dos
principales factores que controlan la reducción de la riqueza de peces (NFSR), es decir, las
interacciones entre las especies acuáticas, variables del hábitat (incluyendo la conectividad
fluvial) y biológicas (incluidas las especies invasoras) en los ríos Júcar, Cabriel y Turia. Con
este fin, tres modelos de ANN fueron analizados: el primero fue construido solamente con
variables biológicas, el segundo se construyó únicamente con variables de hábitat y el tercero
con la combinación de estos dos grupos de variables. Los resultados muestran que las variables
de hábitat son los ¿drivers¿ más importantes para la distribución de NFSR, y demuestran la
importancia ecológica de los modelos desarrollados. Los resultados de este estudio destacan la
necesidad de proponer medidas de mitigación relacionadas con la mejora del hábitat
(incluyendo la variabilidad de caudales en el río) como medida para conservar y restaurar los
ríos Mediterráneos.
El tercer artículo busca comparar la fiabilidad y relevancia ecológica de dos modelos
predictivos de NFSR, basados en redes neuronales artificiales (ANN) y random forests (RF). La
relevancia de las variables seleccionadas por cada modelo se evaluó a partir del conocimiento
ecológico y apoyado por otras investigaciones. Los dos modelos fueron desarrollados utilizando
validación cruzada k-fold y su desempeño fue evaluado a través de tres índices: el coeficiente de determinación (R2
), el error cuadrático medio (MSE) y el coeficiente de determinación ajustado
(R2
adj). Según los resultados, RF obtuvo el mejor desempeño en entrenamiento. Pero, el
procedimiento de validación cruzada reveló que ambas técnicas generaron resultados similares
(R2
= 68% para RF y R2
= 66% para ANN). La comparación de diferentes métodos de machine
learning es muy útil para el análisis crítico de los resultados obtenidos a través de los modelos.
El cuarto artículo tiene como objetivo evaluar la capacidad de las ANN para identificar los
factores que afectan a la densidad y la presencia/ausencia de Luciobarbus guiraonis en la
demarcación hidrográfica del Júcar. Se utilizó una red neuronal artificial multicapa de tipo feedforward (ANN) para representar relaciones no lineales entre descriptores de L. guiraonis con
variables biológicas y de hábitat. El poder predictivo de los modelos se evaluó con base en el
índice Kappa (k), la proporción de casos correctamente clasificados (CCI) y el área bajo la curva
(AUC) característica operativa del receptor (ROC). La presencia/ausencia de L. guiraonis fue
bien predicha por el modelo ANN (CCI = 87%, AUC = 0.85 y k = 0.66). La predicción de la
densidad fue moderada (CCI = 62%, AUC = 0.71 y k = 0.43). Las variables más importantes
que describen la presencia/ausencia fueron: radiación solar, área de drenaje y la proporción de
especies exóticas de peces con un peso relativo del 27.8%, 24.53% y 13.60% respectivamente.
En el modelo de densidad, las variables más importantes fueron el coeficiente de variación de
los caudales medios anuales con una importancia relativa del 50.5% y la proporción de especies
exóticas de peces con el 24.4%. Los modelos proporcionan información importante acerca de la
relación de L. guiraonis con variables bióticas y de hábitat, este nuevo conocimiento podría
utilizarse para apoyar futuros estudios y para contribuir en la toma de decisiones para la
conservación y manejo de especies en los en los ríos Júcar, Cabriel y Turia.Olaya Marín, EJ. (2013). Ecological models at fish community and species level to support effective river restoration [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/28853
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Preston, Yan Wang. "Yangtze - the mother river : photography, myth and deep mapping." Thesis, University of Plymouth, 2018. http://hdl.handle.net/10026.1/12225.
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'The Yangtze is China’s Mother River. It is my Mother River.’ This practice-based PhD research was initially motivated by the researcher’s personal search for The Mother River and a critical question in finding her own vision of the river. As the field experiences contradicted the researcher’s expectation of The Mother River, the research methodology changed and led to a new, critical understanding: The Mother River is mythic. This thesis examines the politics and characters of such a myth. It also asks with what research methods and visual strategy can landscape photography interrogate The Mother River myth’s complexities. Between 2010 and 2014, the author conducted eight field trips to the Yangtze River. Initially working observationally, it soon became apparent that this method alone was insufficient in reaching an original understanding of the physical and cultural Yangtze landscapes. A series of tactile interventions within the landscapes were then performed and critically evaluated prior to the next phase of the research, in which the entire 6,211 km of the Yangtze River was photographed at precise 100 km intervals. A new body of photographic work titled Mother River was produced as a result. To test its effect in challenging the myth, Mother River has been staged in 12 international exhibitions and printed in one complete catalogue. Over 80,000 people visited the shows in China. Deep mapping, which combines experiential and contextual research with multi-sensorial emplacement as a key method, emerged from this research process and is argued as a new contribution to the field of photographic research. Meanwhile, the artistic output of this research, Mother River, is the most systematic documentation of the entire river made by one person since the 1840s. Furthermore, it is argued that using the Y Points System as a physical framework and storytelling a visual strategy, Mother River challenges the mythic Yangtze The Mother River with a scale and complexity rarely employed by other photographers.
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Carrión, Carmona Miguel Ángel. "The effects of the structure on the mechanical behaviour of young Holocene alluvial materials from the Bormida River (Italy) and Turia River (Spain)." Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/63470.
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[EN] The understanding of the mechanical behaviour of natural intact soils is central to engineers when designing new structures. The research carried in this thesis focused on investigating the effects of the naturally occurring in-situ structure on the mechanical behaviour of two shallow recently deposited Holocene alluvial materials, the Bormida River silts (BRS) from Italy and the Valencia silty soils (VSS) from the alluvial plains of the Turia River, Spain. These types of deposits are frequently characterised by highly heterogeneous in-situ structures.
A large range of soils with different size distributions from sands to silty clays were investigated. Oedometer and triaxial tests were carried out on intact, slurry and compacted samples. The first step was to characterise the behaviour of the materials at their reconstituted state to define the reference framework for investigating the effect of the in-situ structure of the intact specimens. The effects of the sample preparation technique on the mechanical behaviour were examined, in particular its influence on the uniqueness of the normal compression line and critical state line. The initial structure created during the preparation of the specimens was totally removed after compression and shearing regardless of the sample preparation method. Only one soil displayed a clear effect of the sample preparation technique, the oedometer compression lines of which remained parallel to each other even at a very high stress levels for the case of the slurry samples. This result showed that contrary to what is stated in the literature the sample preparation technique can created very robust initial structures resulting in a transitional behaviour.
Clears effects of the in-situ structure of the intact samples of the BRS and VSS were observed on the oedometer compression behaviour even at very high stress levels with stress sensitivity values still larger than unity at the end of the tests. It appeared that the effects were more noticeable as the degree of heterogeneity inside the specimens increased at a meso-structure level as it was the case of some samples of the VSS materials which exhibited a certain layering. Small effects of the in-situ structure were seen at large shearing strains and only on the wet side of the critical state.[ES] El conocimiento del comportamiento mecánico de los suelos en su estado natural es de importancia capital para los ingenieros a la hora de diseñar nuevas obras. La investigación desarrollada en esta Tesis se centra en descubrir los efectos que tiene la estructura del suelo en su estado natural en la respuesta mecánica de dos suelos aluviales holocenos, depositados superficialmente: los limos del río Bormida (BRS) en Italia y los suelos limosos provenientes de la llanura aluvial del río Turia (VSS) en España. Este tipo de suelos se caracterizan frecuentemente por una estructura inicial altamente heterogénea. Se ha ensayado una gran variedad de muestras con diferentes granulometrías, desde arenas a arcillas limosas en las que se han realizado ensayos edométricos y triaxiales en muestras intactas, compactadas y en muestras reconstituidas (slurry). En una primera etapa de la investigación se caracterizó la respuesta del material en su estado reconstituido para definir un marco de referencia con el que poder comparar la respuesta de las muestras intactas tomadas in situ y que preservan su estructura natural (inalteradas). Se ha analizado la influencia del modo de preparación de las muestras en su comportamiento mecánico, y, en particular, en la unicidad de las curvas de compresión noval y de estado critico. Se ha comprobado que la estructura inicial inducida durante el proceso de preparación desaparece completamente tras someter la muestra a compresión y corte, independientemente del método de preparación utilizado. Únicamente un suelo mostró, de un modo nítido, el efecto de la técnica de preparación, de modo que las líneas de compresión edométrica se mantuvieron paralelas incluso a niveles de tensión elevados en el caso de muestras reconstituidas (slurry). Este resultado demostró, contrariamente a la opinión aceptada en la bibliografía, que el sistema de preparación de la muestra puede crear una potente estructura inicial dando lugar a un comportamiento de tipo transicional. En los ensayos de compresión edométrica se ha podido comprobar un claro efecto positivo de la estructura inicial de las muestras intactas, incluso a niveles altos de tensión, observándose índices de sensitividad tensional superiores a uno al final de los ensayos, de modo que para igualdad de índice de huecos, la tensión efectiva vertical de la muestra intacta es superior a la correspondiente en la muestra reconstituida. Aparentemente, este efecto es tanto más significativo cuanto mayor es el grado de heterogeneidad interno de la muestra a nivel de meso-estructura, como se pudo observar en algunas muestras de los suelos (VSS) que presentaban niveles de laminación horizontal. En los ensayos de corte la influencia de la estructura intacta fue relativamente pequeña y únicamente en el lado húmedo del estado critico.
[CAT] Conèixer el comportament mecànic dels sòls en el seu estat natural és d'importància capital per als enginyers a l'hora de dissenyar noves obres. La investigació desenvolupada en aquesta Tesi se centra a descobrir els efectes de l'estructura del sòl en el seu estat natural en la resposta mecànica de dos sòls al¿luvials holocens, dipositats superficialment: els llims del riu Bormida (BRS) a Itàlia i els sòls llimosos provinents de la plana al¿luvial del riu Túria (VSS) a Espanya. Aquests tipus de sòls es caracteritzen sovint per una estructura inicial altament heterogènia. S'ha assajat una gran varietat de mostres amb diferents granulometries, des d'arenes fins a argiles llimoses amb les quals s'han realitzat assajos edomètrics i triaxials en mostres intactes, compactades i en mostres reconstituïdes (slurry). En una primera etapa de la investigació es va caracteritzar la resposta del material en el seu estat reconstituït per a definir un marc de referència amb el qual poder comparar la resposta de les mostres intactes preses in situ i que preserven la seua estructura natural (inalterades). S'ha analitzat la influència del mètode de preparació de les mostres en el seu comportament mecànic i en particular, en la unicitat de les corbes de compressió noval i d'estat crític. S'ha comprovat que l'estructura inicial induïda al llarg del procés de preparació desapareix completament després de sotmetre la mostra a compressió i tall, independentment del mètode de preparació utilitzat. Únicament un sòl va mostrar clarament l'efecte de la tècnica de preparació, de manera que les línies de compressió edomètrica es van mantenir paral¿leles fins i tot a nivells de tensió elevats en el cas de mostres reconstituïdes (slurry). Aquest resultat va demostrar, contràriament a l'opinió acceptada en la bibliografia, que el sistema de preparació de la mostra pot crear una potent estructura inicial donant lloc a un comportament de tipus transicional. Als assajos de compressió edomètrica s'ha pogut comprovar un clar efecte positiu de l'estructura inicial de les mostres intactes, inclús a nivells alts de tensió, observant-se índexs de sensitivitat tensional superiors a la unitat al final dels assajos, de manera que per a igualtat d'índex de buits, la tensió efectiva vertical de la mostra intacta és superior a la corresponent en la mostra reconstituïda. Aparentment, aquest efecte és més significatiu quant major és el grau d'heterogeneïtat intern de la mostra a nivell de meso-estructura, com es va poder observar en algunes mostres dels sòls (VSS) que presentaven nivells de laminació horitzontal. Als assajos de tall la influència de l'estructura intacta va ser relativament petita i únicament en el costat humit de l'estat crític."
Carrión Carmona, MÁ. (2016). The effects of the structure on the mechanical behaviour of young Holocene alluvial materials from the Bormida River (Italy) and Turia River (Spain) [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/63470
TESIS
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Leonardo, Pérez Yazmin Mercedes, and Dall’Orso Antoinette Ormeño. "La traducción del fenómeno de la transculturación narrativa en Los ríos profundos/ Deep Rivers de José María Arguedas." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2020. http://hdl.handle.net/10757/652391.
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La transculturación narrativa es un fenómeno que implica la creación de nuevos productos debido a la incorporación de elementos culturales y lingüísticos a una cultura dominante y a la pérdida de los mismos en una cultura dominada. Estos elementos se manifiestan a través de la lengua, estructura literaria y cosmovisión. Dentro del proceso de traducción, los traductores toman decisiones para crear un texto meta que refleje el contexto cultural descrito en el texto original. Al traducir un texto transculturado, el proceso traslativo puede requerir de procedimientos particulares para la correcta reexpresión del mensaje original en el producto que, a su vez, busca la comprensión del público receptor. Por esto, la presente investigación se enfoca en analizar la traducción del fenómeno de la transculturación narrativa al inglés de Los ríos profundos de José María Arguedas traducida por Frances Barraclough. Asimismo, se busca identificar los elementos transculturados en la obra original a fin de reconocer las técnicas de traducción y analizar los paratextos empleados en cada caso. Para este estudio, se propone aplicar la técnica de análisis de contenido mediante la elaboración de un libro de códigos que permitirá identificar y analizar los elementos transculturales en la obra Los ríos profundos. Además, se aplicará la técnica de análisis textual contrastivo mediante fichas para comparar fragmentos, lexemas y sintagmas específicos tanto del texto meta como del texto fuente. De esta manera, se expondrán los procedimientos que Frances Horning Barraclough utilizó para la traducción de los elementos transculturales en Los ríos profundos.Narrative transculturation is a phenomenon that entails creating new products due to the incorporation of cultural and linguistic elements to a dominant culture and their loss on the dominated one. These elements are expressed through language, literary structure and worldview. During the translation process, translators make different kind of decisions in order to create a target text that includes the same cultural equivalence that the original text already has. When a transcultural text is translated, specific procedures are needed to achieve the most accurate rewording of the source text on the final product which, at the same time, seeks for the understanding of the target audience. Therefore, the following research focuses on the analysis of the narrative transcultural translation phenomenon on Deep Rivers, written by José María Arguedas and translated by Frances Horning Barraclough. In addition, the aim of this investigation is to identify the transcultural elements in Los ríos profundos with the purpose of recognizing the translation techniques and analyze the use paratexts during the translation process. In this investigation, in order to identify and analyze transcultural elements in Los ríos profundos, content analysis technique will be use through the elaboration of the codification book. Furthermore, the contrastive textual analysis technique will be applied through index tabs to show fragments, lexemes and syntagmas of both the source and target text. As a result, the procedures that Frances Horning Barraclough used for the translation of the transcultural elements in Los ríos profundos will be presented.
Trabajo de investigación
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Dingwall, James R. "The design of a deep water catenary riser." Thesis, University of Glasgow, 1997. http://theses.gla.ac.uk/1636/.
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The overall aim of this study is to propose and develop a cost effective production design concept suitable for oil reservoirs situated in deep (1500 m) water which can be quickly and safely installed in areas with limited weather windows. The proposed design is based upon a steel catenary riser which will connect an FPSO directly into either a wellhead or seabed pipeline system thereby eliminating both the connection complexes and high cost associated with a central manifold. The catenary geometry will ensure that the structure is inherently compliant whilst a carrier pipe arrangement will provide structural protection and buoyancy to a flowline bundle contained within. The interface between the riser and the surface production vessel is a critical part of any riser system and so for the purposes of this study two design arrangements are considered. The first is based upon a direct connection between an FPSO turret and riser whereas the second is a hybrid design in which the riser is supported by a sub-surface buoy which is hydraulically connected to an FPSO using flexible flowlines. This hybrid connection has the advantage of decoupling FPSO and riser motions. Design development is carried out by examining a range of critical areas.
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Wood, Christopher Karl. "The effects of prescribed burning on deer and elk habitat parameters in Montana's Missouri River Breaks." Thesis, Connect to this title online Connect to this title online (alternate address), 2004. http://www.montana.edu/etd/available/wood%5F1204.html.
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Bustros-Lussier, Elyse. "Identifying deep-groundwater discharge in rivers of eastern Ontario." Thesis, University of Ottawa (Canada), 2008. http://hdl.handle.net/10393/27579.
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Interactions between surface water systems and groundwater systems are poorly understood. This research focuses on the surface water/groundwater interactions that use an electric conductivity and temperature (EC&T) drag probe in the Raisin River and South Nation Watershed.
To find groundwater seepages into rivers, a Reelogger Model 2001 probe (Solinst Canada Ltd) was dragged at the sediment-water interface to measure EC&T for several reaches of the Raisin River, the Castor River, the East Castor and the South Nation River. GPS position data was collected at the same time as the EC&T measurements which allows the data to be input into a GIS database for management decisions. During the summer, groundwater typically had higher EC and lower T values than the surface water, and so increases in EC occurring along with lower water temperatures were inferred to be deep-groundwater discharge locations. High EC values can be explained either by deep groundwater discharge (seeps) or by local anthropogenic loading of sediments into the river. In rivers with low permeability clay streambeds very few locations of significant discharge were detected using this method. The most significant discharge area, called the "Swimming Hole" by local residents, was surveyed at large and small scale and groundwater seepage was found to be present along the shore and in the middle. However, the EC&T probe appears to have identified relatively high flux discharge zones in the Castor and East Castor River at locations where highly permeable eskers cross the rivers. The survey identified approximately a 50 m area along the Castor river and a 100m area along the East Castor River where EC values were as high as 2000 muS/cm and temperature as low as 11°C. They were investigated and fluxes quantified by installing and testing piezometers and deploying seepage meters.
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Malinský, Martin. "Založení stavby River Garden III v Praze." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227540.
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The topic of this master's thesis are the design of ensuring foundation pit and foundation of administrative building in Prague. In the vicinity of foundation pit is situated the river Vltava, which directly influences the ground water level at the job site. During construction, it is necessary to envisage the possibility of occurrence of the old building structures of docks.
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Bhattarai, Indu. "Quantitative River Profile Analysis to Investigate Exhumation of the Siwalik Foreland Basin, Nepalese Himalaya." TopSCHOLAR®, 2017. http://digitalcommons.wku.edu/theses/1932.
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The Nepalese Himalaya, one of the most active regions within the Himalayan Mountain belt, is characterized by a thick succession of Miocene age Siwalik sedimentary rocks deposited at its foreland basin. To date, much of its tectonic evolution, including exhumation in the Nepalese Siwalik, is poorly understood. This study of a quantitative analysis of the bedrock river parameters should provide crucial information regarding tectonic activities in the area. The study investigated geomorphic parameters of river longitudinal profiles from 54 watersheds within the Siwalik section of the Nepalese Himalaya, for the first time. A total of 140 bedrock rivers from these watersheds were selected using stream power-law function and 30-meter resolution ASTER DEM. The quantitative data from the river longitudinal profiles were integrated with published exhumation ages. Results of this study show, first, a presence of major and minor knickpoints, with a total of 305 knickpoints identified, of which 180 were major knickpoints and the rest were minor knickpoints. Further classifications of knickpoints were based on structures (lineaments extracted from SRTM DEM), lithology, and possible uplift. Second, the Normalized Steepness index (ksn) values exhibited a range from 5.3 to 140.6. Third, the concavity index of streams in the study area ranged from as low as -12.1 to as high as 31.1 and the values were consistently higher upstream of the knickpoints. Finally, integration of the river profile data with the published exhumation ages show that the regions with a high ksn value correspond to the regions with higher incision and,
therefore, are likely to have high uplift. The presence of a break in ksn in the eastern section of the study area suggests that the incision is likely accelerated by Main Frontal Thrust (MFT) movements. Erosion of the thrust sheet could have influenced the rapid uplift of the Siwalik due to isostatic processes. Thus, the timing of the source-region exhumation and its rate suggests that MFT-related tectonics, and/or climate processes, likely influenced the landscape evolution of the study area. The results of this study should help in comprehending the neo-tectonic deformation of the Nepalese Himalaya.
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Napoleone, Sara. "Stima con modelli idrologici del rischio idraulico del Rio Torriane." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2022.
Find full textAbstract:
The flooding of a watercourse is one of the major environmental risks linked to human activities, with consequences on the safety of the population and economic losses due to the interruption of services. It is therefore necessary to define intervention strategies for the hydraulic protection of areas potentially subject to flooding. There is a clear need for increasingly detailed analyses of these phenomena, to foresee and define the most exposed areas and design defense works, by evaluating case by case the best solution between structural and non-structural interventions.
This study, carried out in collaboration with the Consorzio delle Bonifica Renana, aims to analyze the hydraulic functioning of the Torriane River, a hilly watercourse that is a left tributary of the Savena torrent in the municipality of Bologna. The hydrographic left of the Torriane River is partly occupied by a public road system subject to periodic overflows during the most intense rainfall events. Using the rational method, the flood flows are defined, relative to return period, of 2, 30 and 200 years. Flood flows are evaluated basing on the local rainfall regime and the characteristics of the basin.
The calculation protocol related to the study of the rainfall regime is established by the competent basin authority, which publishes the regionalization models of rainfall and flow rates relative to the various regional basins. The geometric features of the Torriane basin and its sub-basins were defined through a detailed analysis. Once the flood flows were defined, the estimation of the extent of the floodable areas was carried out using the Hec-Ras software.
In order to design the hydraulic works of the basin, aimed at preventing new floods, preliminary survey and in situ investigation activities have been developed. The reshaping of the riverbed and the creation of a retaining wall to support the road system are proposed solutions to reduce the risk of flooding in critical sections.
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Tu, Denise Shao-Wai. "Assessment of Methods for Monitoring Responses to River Restoration: Riverbed and Channel Form Changes." Thesis, University of Oregon, 2011. http://hdl.handle.net/1794/11505.
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xi, 54 p. : ill. (some col.)On the Middle Fork John Day River (MFJD), a low gradient, meandering river in eastern Oregon, restoration includes engineered log structures intended to increase in-stream complexity and habitat diversity. Effects of log structures on riverbed topography can be captured through repeat topographic surveys, digital elevation model (DEM) of differencing (DoD), and aerial imagery. This study evaluates the (1) potential for remote sensing analysis, (2) effect of survey point density on DEMs, and (3) application of DoDs, in monitoring riverbed changes in the MFJD. An average point spacing and density finer than 0.50m and 1.25pts/m
Committee in charge: Patricia McDowell, Chairperson; Andrew Marcus, Member
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Calvo, Tortajada Rubén. "Implementación del lidar terrestre en la caracterización y modelización de análogos de reservorios fluviales: desarrollo y aplicación de nuevas metodologías en afloramientos del abanico fluvial de Huesca (Mioceno de la Cuenca del Ebro)." Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/396368.
Full textAbstract:
Las nuevas técnicas de recolección de datos digitales surgidas en los últimos años han dado lugar a avances significativos en el campo de la caracterización de afloramientos. Esta evolución se basa en la premisa de que cuanto mayor sea la cantidad, la calidad (exactitud), y la velocidad de recolección de los datos, mejores serán las interpretaciones y modelos que se deriven de ellos. Una de las técnicas más recientemente incorporadas en el estudio de afloramientos geológicos es el escaneo láser terrestre (TLS), el cual se basa en la tecnología lidar (desarrollada en la década de 1960).
El objetivo principal de esta tesis es aprovechar el potencial del TLS para desarrollar nuevas herramientas y metodologías que permitan resolver la principal limitación a la que se enfrentan los geólogos cuando trabajan en afloramientos fluviales: adquirir el control estratigráfico necesario para detectar, comprender y caracterizar el alto grado de heterogeneidad en el espacio y el tiempo que muestran las sucesiones fluviales.
Con este propósito se han adquirido datos con TLS en 8 afloramientos del Abanico Fluvial de Huesca (Mioceno inferior, norte de España). Se han utilizado softwares comerciales para procesar las nubes de puntos adquiridas y así obtener Afloramientos Virtuales (VO’s), pero la mayor parte de los logros obtenidos de su estudio fueron posibles gracias softwares desarrollados en la propia facultad. Por otro lado, también se han medido varias columnas estratigráficas detalladas y se recogieron muestras litológicas de diferentes tipos de cuerpos areniscosos. En base a estos datos y a las observaciones realizadas sobre el terreno los resultados más relevantes obtenidos son los siguientes:
* Una caracterización detallada de las facies fluviales, la cual incluye el estudio de las propiedades petrológicas y petrofísicas de los cuerpos areniscosos.
* Un método simple que se sirve del VO para corregir las alturas y espesores de los cuerpos sedimentarios medidos en las columnas estratigráficas. Los principales factores que pueden haber influido en las mediciones realizadas con Vara de Jacob han sido estudiados y discutidos.
* Se ha establecido un nuevo método que permite realizar correlaciones semiautomáticas y altamente precisas en los VO’s de afloramientos fluviales, el cual se basa en la hipótesis de que el paleosuperficie deposicional del sistema sedimentario puede ser representada por un plano a escala de afloramiento. Si esta suposición se cumple en el afloramiento, este plano puede ser utilizado como un datum virtual para identificar a lo largo del VO los sedimentos que fueron depositaron simultáneamente. El método ha sido probado y aplicado con éxito en cuatro afloramientos de escala kilométrica del Abanico Fluvial de Huesca, en los cuales los datums virtuales han proporcionado correlaciones precisas independientemente de las complejidades estratigráficas o topográficas de los mismos. Además, únicamente con mover el datum virtual se puede subdividir toda la sucesión sedimentaria de los afloramientos en los intervalos estratigráficos deseados, los cuales pueden ser aislados del resto para facilitar su estudio en detalle.
* Los datums virtuales también se han utilizado como base para establecer un nuevo procedimiento que permite inferir cuales son las posiciones estratigráficas relativas dentro de toda la secuencia fluvial de afloramientos que distan decenas de kilómetros.
* Se ha realizado una modelización estocástica de facies basada en objetos que se sirve de los datos obtenidos al aplicar un nuevo método para extraer de una manera semiautomática las superficies del VO que pertenecen a paleocanales. Los flujos de trabajo de modelización de análogos habituales utilizan los datos de columnas estratigráficas (en forma de pseudopozos) para condicionar las simulaciones, pero con el método presentado aquí toda la superficie del afloramiento es considerada para este propósito, aumentando significativamente de ajuste del modelo a la realidad.
Gracias a la utilización de la tecnología lidar en afloramientos del Abanico Fluvial de Huesca se han conseguido establecer diferentes métodos de trabajo que han demostrado ser útiles de cara a facilitar y mejorar la construcción de modelos de análogos de reservorio. Además, se considera que su aplicación puede sin duda contribuir a mejorar nuestra comprensión de los factores y mecanismos que influyeron en la evolución de los sistemas sedimentarios fluviales antiguos.Terrestrial laser scanning (TLS) is based on lidar technology, which although developed in the early 1960s, has only recently been incorporated into the study of geological outcrops. The main aim of this thesis is to take advantage of the potential of the TLS to provide new tools and methodologies focused on solving the main limitation found by the geologists when working in fluvial outcrops: acquire the degree of stratigraphic control required to detect, understand and characterize the high degree of spatial and temporal heterogeneity of fluvial successions. TLS data from 8 outcrops of the Huesca Fluvial Fan (Early Miocene, northern Spain) were acquired to this purpose. In addition, several detailed stratigraphic columns were measured and lithological samples from different types of sandstone bodies were collected. Based on this, the most relevant results obtained are as follows: * A comprehensive characterization of the fluvial facies that includes the petrological and petrophysical properties of the sandstone bodies. * A simple method using the VO to correct the heights and thicknesses of the sedimentary bodies measured in the stratigraphic columns. The main factors that may have influenced the measurements made with the Jacob’s staff have been studied and discussed. * A new method leading to obtain a virtual datum is presented in response to the need for further correlation procedures, especially in the absence of suitable datums. This virtual datum enables to achieve highly accurate and semiautomatic correlations within fluvial VO’s. Moreover, all the sedimentary successions of the outcrops can be automatically subdivided into the desired stratigraphic intervals (which can be later isolated) by only moving the virtual datum vertically. * The virtual datums were also used to establish a new procedure that leads to infer the relative stratigraphic positions of distant outcrops (more than 10 Km apart) inside the entire fluvial sequence. * A facies modelling has been performed using a new method to extract in a semiautomatic way the surfaces of the outcrop that belong to paleochannel exposures.
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Spencer, Amy B. "Habitat Characteristics and Fish Assemblage Structure of Deep Pools in the Upper Tombigbee River, Mississippi." MSSTATE, 2007. http://sun.library.msstate.edu/ETD-db/theses/available/etd-02192007-170440/.
Full textAbstract:
Fish assemblage structure in lotic environments is a product of interactions between the habitat and the biota, but little is known about how deep pool habitat conditions affect distributional patterns of fish occupying them in larger warmwater streams. This study describes relationships between the habitat and the fish assemblages in deep pools of the Upper Tombigbee River, Mississippi. Pools exhibited an increase in size from headwaters to mouth. The change in the structure of fish assemblages was related significantly to increases in pool size while independent of time or other environmental conditions. A small amount of the variation in structure of fish assemblages in deep pools was accounted for by the measured environmental variables. This suggests other factors such as biotic interactions play an additional role in the forming the observed distributional patterns in fishes occupying deep pools.
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Vercellino, Marco. "Effetti di un atmospheric river atlantico sulle precipitazioni intense del 2 ottobre 2020 sulle Alpi." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/23480/.
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Studi recenti hanno evidenziato, in Europa e nel bacino del Mediterraneo, uno stretto legame tra lo sviluppo di un atmospheric river (AR) e eventi di precipitazioni intense. Un AR è un corridoio lungo, stretto e transitorio in cui si verifica un forte trasporto orizzontale di vapore acqueo concentrato nei primi km di troposfera. E' associato ad un low-level jet (LLJ) davanti al fronte freddo di un ciclone extratropicale. La grande quantità di vapore acqueo trasportata può produrre intense piogge
in corrispondenza di un sollevamento orografico dell'AR.
Il lavoro di tesi riguarda lo studio di un evento di forti precipitazioni che hanno interessato il nord Italia tra il 2 e il 3 ottobre ed il ruolo rivestito da un AR nell'alimentazione delle stesse. Attraverso simulazioni modellistiche si sono identificati i principali meccanismi dinamici e termodinamici responsabili dell'evento. L’analisi delle traiettorie delle masse d’aria che hanno raggiunto l’area di intense piogge, eseguite per mezzo del modello HYSPLIT, ha permesso di identificare l’origine del vapore acqueo che ha alimentato le precipitazioni e ha rivelato una complessa sovrapposizione di diverse correnti incidenti sull’orografia alpina. Un trasporto proveniente dall’Oceano Atlantico e associato all’AR a quote medio-alte, un trasporto dal Mar Tirreno a quote inferiori ed infine un contributo dal Mar Adriatico sulla Pianura Padana nei livelli più bassi. Le simulazioni effettuate con i modelli numerici meteorologici BOLAM e MOLOCH hanno permesso di riprodurre i campi di precipitazione osservati e di caratterizzare il trasporto di vapore nell’intera troposfera, in confronto al contributo del LLJ sviluppatisi sul Mar Tirreno. Infine, per mezzo di esperimenti numerici di sensibilità, è stato possibile isolare e quantificare il ruolo dell’AR nell’alimentare le piogge. I risultati hanno confermato che l’AR ha avuto una importanza critica nel trasformare un episodio di precipitazione intensa in un evento alluvionale.
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Craig, Phillip Scott. "An oceanographic research facility." Thesis, Virginia Polytechnic Institute and State University, 1994. http://hdl.handle.net/10919/53370.
Full textAbstract:
The natures of two contiguous worlds in a dramatic symbiosis inspire a singular expression for the two. The moving, highly energetic, brought to order through regulation; not abruptly, but sensitively, through dynamic forms and moving interactions. Land joins water and forms a critical edge that through the mechanism of change is never fully determined. A moving contour presents a foil to the more orderly, precise nature of man-made construction. A building manifests itself as a bridge that unites the realms of land and water. The orderly progression of structural piles assumes power against the backdrop of an unordered field. Suspended pathways traverse the field, uniting the realms and organizing the waterfront. It is the nature of connection: the union of two made possible by a third. Beyond the connection implied of two contiguous realms, a larger order poses its question. What is the sense of belonging; the intimate connection; belonging to and of this place? Validation extends from referencing the immediate site and surrounding area. Perceived and associative images, as well as indigenous forces inform the design and help determine the forms and manner of execution. The exigencies of the site provide the framework for expression. From the Poetics of Gardens: "Sometimes the most poignant qualities of site come not from what is actually there but from what is connected to it through time and space, by our recollections and hopes." An Oceanographic Research Facility, derived from forces and forms indigenous to the coastal milieu, emerges as a platform to experience Land and Sea and by definition, unified: joined in a common sense or relationship.Master of Architecture
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Simancas, Tejedor Moisés. "Las fuentes intelectuales del fascismo español la génesis del pensamiento de José Antonio Primo de Rivera y su desarrollo hasta noviembre de 1934 /." Madrid : Ed. de la Universidad autónoma de Madrid, 1999. http://catalogue.bnf.fr/ark:/12148/cb39037363n.
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Tesis doct.--Departamento de filosofía--Madrid--Universidad autónoma, 1999.La page de titre porte en plus : "Facultad de filosofía y letras. Filosofía" Bibliogr. p. 438-561. Résumés en espagnol et en anglais.
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Ortiz, Peña Victor Alejandro, and Milos Dinic. "Satellite derived data to support flood modelling : An application to the Po River." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-230889.
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Satellite derived data has become an essential input in hydraulic modelling. Digital ElevationModels (DEMs) derived from different sources through remote sensing techniques have become a powerful tool for poorly gauged regions. This paper analyses the capabilities of DEMS derived from Shuttle Radar Topography Mission (SRTM) and a Light Detection and Ranging (LiDAR) and compares their accuracy against each other in a 1D hydraulic model. The study tests two different methods for inferring the river bathymetry under the water surface level for the SRTM derived DEM in order to enhance its performance, the study further analyze the reliability of remotely sensed altimetry data derived from different satellite missions (TOPEX and ENVISAT) and its suitability to complement spaceborne topographic data in hydraulic modelling.
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Timmons, Sara J. "Developing a plan to support mathematics students with advanced placement potential at Indian River High School." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 116 p, 2009. http://proquest.umi.com/pqdweb?did=1833621121&sid=8&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Marcé, Romero Rafael. "Ter River influence on Sau Reservoir limnology. Empirical and watershed-scale modeling." Doctoral thesis, Universitat de Barcelona, 2007. http://hdl.handle.net/10803/1437.
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The role of the materials coming from the watershed on the reservoir water quality is an emergent area of high scientific interest with many practical implications. In this study we investigated the influence of the materials coming from the Ter River watershed on the eutrophication process of Sau Reservoir, located in Barcelona (Spain).First, we present a new methodology to calculate nutrient river loads, using fuzzy logic and tools from neural-networks optimization algorithms. The new method was more efficient and accurate than classical procedures.
Then, we demonstrate the effect of river materials (especially that of dissolved organic carbon) on the development of anoxic layers in the bottom layers of the reservoir. These results are not limited to Sau Reservoir, since other reservoirs in the world have shown the same responses.
The second part of the dissertation develops a watershed-scale model for the Ter River and the Sau Reservoir using HSPF. This included hydrology, river water temperature, and river total phosphorus concentration. Results were satisfactory, and the model implementation allowed testing state-of-the-art algorithms to calibrate complex models, based on the Bayesian statistical theory. On the other hand, different alternatives to model river water temperature were tested. Finally, we explored the possibility of using field data collected at the river reach scale, following the Nutrient Spiralling Concept, to parameterize the river total phosphorus model in the Ter watershed, with encouraging results.
CATALÀ:
L'efecte dels materials provinents de la conca de drenatge en la qualitat de l'aigua del embassaments és un àrea d'investigació amb considerable interès teòric i pràctic. En aquest estudi s'ha investigat la influència de les aportacions de la conca de drenatge del riu Ter en el procés d'eutrofització de l'embassament de Sau, a la província de Barcelona (Espanya).
Primer es detalla un nou mètode de càlcul de càrregues de nutrients en rius, fent servir la lògica difusa i eines provinents de l'optimització de xarxes neuronals. El nou mètode ha provat ser més eficient i precís que les alternatives clàssiques.
Després s'ha demostrat empíricament l'efecte dels materials provinents del riu (especialment del carboni orgànic dissolt) en la generació de capes anòxiques al fons de l'embassament. Aquest resultats no s'han aplicat només en el cas de l'embassament de Sau, sinó que han demostrat ser extrapolables a d'altres sistemes inundats de diferents llocs del planeta.
La segona part de la Tesi desenvolupa un model a escala de conca pel riu Ter i l'embassament de Sau amb HSPF, incloent hidrologia, la temperatura de l'aigua al riu, i la concentració de fòsfor total al riu. Els resultats han estat satisfactoris, i a més la implementació del model ha permès testar eines modernes de calibració de models complexos basades en l'estadística Bayesiana. Per altra banda, s'han testat diferents alternatives per a la modelització de la temperatura d'aigua en rius. Finalment, s'ha investigat la possibilitat de fer servir dades de camp recollides a escala de tram de riu, seguint el Nutrient Spiralling Concept, per a la parametrització del model de fòsfor total al riu Ter, amb resultats estimulants.
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Puckett, Kerri A. "Uncertainty quantification in predicting deep aquifer recharge rates, with applicability in the Powder River Basin, Wyoming." Laramie, Wyo. : University of Wyoming, 2008. http://proquest.umi.com/pqdweb?did=1594477301&sid=2&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Casas, Ruiz Joan Pere. "Controls on the dynamics of riverine dissolved organic matter: insights from a Mediterranean river network." Doctoral thesis, Universitat de Girona, 2017. http://hdl.handle.net/10803/404280.
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In river networks, dissolved organic matter (DOM) constitutes the major pool of organic carbon, and plays a key role as energy source and modulator of toxic substances availability. In this thesis, Joan P. Casas-Ruiz and collaborators provide new insights into the controls on DOM processing, and into how in-stream reactions and changing DOM sources modulate DOM dynamics in river networks. To attain this, the quantity and composition of DOM were evaluated across a river network throughout a full hydrological year. The results compiled in this thesis pose water residence time as the main regulator of DOM processing, while DOM properties as well as nutrient availability determine the net balance of in-stream degradation and production of DOM. A network-scale analysis identifies a pattern of DOM concentration and chemical diversity with maxima in medium-sized rivers, and the same pattern emerges upon analysis of a global data set. On the basis of these results, this thesis proposes a conceptual framework to comprehend and predict the spatiotemporal dynamics of riverine DOMLa matèria orgànica dissolta (DOM) constitueix la major reserva de carboni orgànic en els sistemes fluvials, on també hi juga un paper clau com a font d'energia i modulador de la disponibilitat de substàncies tòxiques. En aquesta tesi, Joan P. Cases-Ruiz i col•laboradors pretenen identificar els controls de processament DOM, i entendre com la combinació de reaccions in situ i canvis en les fonts de DOM modulen les dinàmiques de la DOM fluvial. Per tal d'assolir-ho, es van evaluar la quantitat i composició de la DOM en una xarxa fluvial al llarg d'un any hidrològic complet. Els resultats recopilats en aquesta tesi assenyalen el temps de residència de l'aigua com el principal regulador de processament de la DOM, mentre que les propietats intrínsiques de la DOM, així com la disponibilitat de nutrients determinen el balanç net de degradació i producció de la DOM. Una anàlisi a escala de xarxa fluvial identifica un patró de concentració i diversitat química de la DOM amb màxims en els rius de mida mitjana. En base a aquests resultats, aquesta tesi proposa un marc conceptual per comprendre i predir les dinàmiques espacials i temporals de la DOM fluvial
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Sabater, Liesa Laia. "Disentangling the complexity of chemical and physical stressors impacting river systems." Doctoral thesis, Universitat de Girona, 2021. http://hdl.handle.net/10803/671769.
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Humanity has always been closely linked to rivers, benefiting from their resources while producing impacts associated with their activity.Thus, river systems have been exposed to multiple stressors, which have affected the quality of water and their biological communities, such as those attached to substrata (biofilms) or those that are suspended in water (phytoplankton). On the other hand, biological communities also respond and contribute to the transformation and/or degradation of certain anthropogenic organic compounds, such as pharmaceuticals. This thesis investigates the chemical state of the river systems and their impacts on the biological communities, using different approaches and scalesLa humanitat ha estat sempre íntimament lligada als rius, beneficiant-se dels seus recursos però també produint impactes vinculats a la seva activitat. Així doncs, els sistemes fluvials han estat exposats a múltiples estressos, que han afectat la qualitat de l’aigua així com a l’ecosistema de les seves comunitats biològiques, com les adherides al biofilm o bé les que estan en suspensió a l’aigua, com el fitoplàncton. A més, les comunitats biològiques també responen i contribueixen a la transformació i/o degradació d’alguns compostos orgànics d’origen antropogènic, com els fàrmacs. Aquesta tesi investiga l’estat químic dels sistemes fluvials, i els seus impactes, utilitzant diferents aproximacions i escales
Programa de Doctorat en Ciència i Tecnologia de l'Aigua
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Del, Sante Montes Luis Edgar, Balbín Edith Beatriz Pérez, Sobenes Andrés Cano, and Huachaca Fidel Oscar Calderón. "Índice de progreso social del distrito de José Luis Bustamante y Rivero." Master's thesis, Pontificia Universidad Católica del Perú, 2021. http://hdl.handle.net/20.500.12404/19436.
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El reto por alcanzar los objetivos de desarrollo social es cada vez más exigente para
las instituciones y los hacedores de política, con la finalidad de erradicar la pobreza, alcanzar
mayor bienestar para la población y garantizar el desarrollo sostenible con la protección del
medio ambiente. Por lo que, es de vital importancia contar con una herramienta que mida
eficientemente el nivel de bienestar de una localidad, región o país; con esa finalidad el
Social Progress Imperative [SPI] presentó el Índice de Progreso Social [IPS] a partir de un
modelo holístico que integra los temas más relevantes para la sociedad.
La presente investigación cuantifica el Índice de Progreso Social del distrito de José
Luis Bustamante y Rivero [JLBYR], ubicado en la provincia de Arequipa, región Arequipa;
el cual alcanzó 58.89 puntos ubicado en el nivel medio bajo. A nivel de dimensiones,
Necesidades Básicas Humanas alcanzó el nivel medio alto con 71.84 puntos; seguido de la
dimensión de Oportunidades con 60.66 puntos en el nivel medio bajo; y Fundamentos de
Bienestar con 44.18 puntos en el nivel muy bajo. Los resultados obtenidos en la estructura del
IPS permite determinar el nivel de progreso social, así como determinar las brechas que
enfrenta por cada componente y dimensión. El distrito se zonificó en tres zonas norte, centro
y sur; siendo la zona I la que registra mayores ventajas frente a las zonas II y III.
El IPS del distrito de JLBYR, permitirá promover el progreso social como
herramienta al gobierno, las empresas y la sociedad civil, entre otros; y crear sinergias en
contribución a alcanzar los objetivos de Desarrollo sostenible, e intervenir con la inversión
social en los espacios que requieren mayor atención como en los componentes de
sostenibilidad ambiental y derechos personales en el distrito.The challenge to achieve the objectives of social development is increasingly demanding for institutions and policy makers, with the aim of eradicating poverty, achieving greater well-being for the population and guaranteeing sustainable development with the protection of the environment. Therefore, it is vitally important to have a tool that efficiently measures the level of well-being of a locality, region or country. To this end, the Social Progress Imperative [SPI] presented the Social Progress Index [SPI] based on a holistic model that integrates the most relevant issues for society. The present investigation quantifies the Social Progress Index of the José Luis Bustamante y Rivero [JBLYR] district, located in the province of Arequipa (Arequipa region). This district reached 58.89 points which placed it in the lower middle level. At the dimensions level, Human Basic Needs reached the medium high level with 71.84 points. The Opportunities dimension reached the lower middle level with 60.66 points. On the other hand, Foundations of Well-being obtained 44.18 points, so it reached the lower level. The results obtained in the SPI structure allow to determine the level of social progress as well as to determine the gaps that it faces for each component and dimension. The district was zoned into three northern, central, and southern zones; being zone I the one that registers greater advantages compared to zones II and III. The SPI of the JLBYR district will allow promoting social progress as a tool for the government, companies and civil society, among others. In addition, it will create synergies in contribution to achieving the Sustainable Development goals, and intervene with social investment in spaces that require greater attention, such as the components of environmental sustainability and personal rights in the district.
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Toure, Sene El hadji Oumar. "Enfoque ecosistémico del territorio para una gestión integrada del delta del río Senegal." Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/400709.
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Las dimensiones sociales y biofísicas de los ecosistemas están íntimamente relacionadas entre sí creando complejas sinergias en múltiples escalas temporales y espaciales. El marco teórico del sistema socioecológico (SSE) desde una perspectiva institucional y del enfoque ecosistémico (EE) se han utilizado en esta tesis para identificar y analizar los principales subsistemas y las variables a considerar en el caso del delta del río Senegal (República de Senegal), con el objetivo último de proponer acciones para una gestión integrada del territorio. Para poner en práctica las conceptualizaciones alcanzadas, resultaba fundamental y de interés estudiar los usos que están en relación con los ecosistemas, mediante los cuales es posible predecir y estimar las afectaciones que una actividad, obra o política de desarrollo producen sobre un entorno deltaico complejo de por sí, a la vez afectado por el cambio climático y las actuaciones hidroagrícolas (presas de Diama y Manantali, canal de la Lengua de Barbarie). Al referirnos de un territorio que alberga múltiples usos y actores, las actividades de agricultura, pesca y turismo se seleccionaron como casos de estudio, en tanto que actividades más relevantes en la región desde el punto de vista socioeconómico.
Como resultado, destacamos que las acciones antrópicas tuvieron más relevancia que aquellas provocadas por el clima en el área de estudio y que existen graves problemas socioambientales. Históricamente, el territorio se había caracterizado por sistemas tradicionales de subsistencia fuertemente dependientes de las inundaciones del río. Con la llegada del periodo colonial se crearon cultivos de rentas como medida para combatir los años de sequía que imposibilitaron el cultivo de secano. Actualmente, el delta presenta dos socioecosistemas distintos: en el norte, los socioecosistemas implementados por grandes firmas comerciales y en el sur, los socioecosistemas familiares de subsistencia. Los conflictos sociales sobre los recursos y las reivindicaciones del derecho de propiedad, el acceso al agua, la tierra o el pacto de gestión conjunta se presentan cada vez con más virulencia en este espacio debido al incremento de la dependencia de los ecosistemas para satisfacer las necesidades de una población mayoritariamente pobre.
Con este panorama como trasfondo, surge el análisis DAFO (Debilidades, Amenazas, Fortalezas, Oportunidades) del enfoque territorial bajo diversos criterios según las siguiente perspectivas: lucha contra la pobreza y fomento de la cohesión social, control de los efectos de los usos económicos, mejora de la calidad de los recursos y diversidad de especies, lucha contra el cambio climático, e integrar lo local al global y fomento de la gestión conjunta. El análisis de las distintas matrices DAFO permite entender los factores negativos (debilidades y amenazas) y positivos (fortalezas y oportunidades) cuyos orígenes pueden ser tanto territorial e intrínseco del delta o extrínseco, es decir en relación con el contexto regional, nacional o internacional. Tras evaluar y territorializar cada uno de los factores (internos y externos) se implementó una estrategia para corregir las debilidades, afrontar las amenazas, mantener las fortalezas, explotar las oportunidades. La tesis puso de manifiesto la urgencia de implementar una gestión integrada como alternativa para crear empleo y evitar la emigración de los jóvenes, así como mejorar la conservación de los recursos naturales.The social and biophysical dimensions of the ecosystems are closely linked to each other thus creating complex synergies at multiple temporal and spatial scales. The theoretical framework of the social-ecological system (SES) from an institutional perspective as well as of the ecosystem approach (EA) have been used in the present thesis in order to identify and analyze the main subsystems and to look into the variables related to the Senegal River Delta (the Republic of Senegal) with the ultimate objective of suggesting measures to be taken for the integrated management of the territory. In order to put into practice the conceptualizations reached, it resulted fundamental and interesting to study the uses linked to the ecosystems by which it’s posible to predict and estimate the effects of an activity, construction work or development policy on the delta environment which is in itself complex and at the same time is affected by climate change and the hydroagricultural intervention (the Diama and Manantali dams, the Barbarie Tongue channel). When referring to the territory that serves as a site for multiple uses and actors, the case studies chosen represent the most relevant activities in the region from a socio-economic viewpoint, such as agricultural activities, fishing and tourism. As a result, we emphasize that the anthropic actions have had more influence than those caused by the studied area’s climate conditions, and that there exist some major socio-environmental problems. Historically, the territory has been characterized by traditional subsistence systems which have been considerably dependent on the river’s inundations. With the arrival of the colonial period cash crops were created as a measure to combat the drought years which had made the dry farming impossible. At the moment the delta represents two different socio-economic systems: in the north, the socio-economic systems implemented by big companies and in the south, the socio-economic systems characterized by family-run subsistence agriculture. The social conflicts over natural resources and property rights claims, access to water, land or joint management agreement are increasingly becoming more hostile in this area due to the increase of the dependency on the ecosystems in order to satisfy the necessities of a predominantly poor population. Taking into account this background, the SWOT analysis has been employed (strengths, weaknesses, opportunities, threats) with the territorial approach being adopted applying a number of criteria and according to the following perspectives: the struggle against poverty and enhancement of social cohesion, monitoring the effects of economic uses, improvement of the resources quality and the species diversity, fight against climate change, integration of the local to the global level and enhancing of co-management. The analysis of the SWOT matrix allows to understand the negative (weaknesses and threats) and positive (strengths and opportunities) factors whose origins can be both territorial and intrinsic of the delta, as well as extrinsic, that is to say in relation to the regional, national or international context. After evaluating and territorializing each factor (interior and exterior), there was implemented one strategy in order to deal with weaknesses, tackle threats, maintain the strengths, explore the opportunities. The thesis highlighted the urgency of implementing an integrated management as an alternative with the aim of creating jobs and preventing the emigration of young people as well as with the aim of improving natural resources conservation.
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Haan, Damon. "Habitat use and den site selection of mink (Mustela vison) along the Hudson River and its tributaries in east-central New York." OpenSIUC, 2011. https://opensiuc.lib.siu.edu/theses/661.
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Mink (Mustela vison) are an important species because they occur at a high trophic level, they are considered a potential indicator species for environmental contaminants, and they are a popular target species among fur trappers. Despite the importance of mink, their ecology in North America is not well understood. I sampled 59 of 60 Hudson River tributaries with 2 scent stations randomly established along each tributary for 2 10-day monitoring periods to evaluate presence/absence of mink via remote camera photographs and tracks. When sampling was completed, I quantified microhabitat characteristics at 84 randomly selected scent stations. Statistical tests for microhabitat did not indicate a difference among variables selected for analysis between scent stations where mink visits were detected and those where mink visits were not detected. I also analyzed all scent stations for macrohabitat characteristics related to human disturbance, using 150 m circular buffers in ArcGIS 9.2. Although the percent cover of human disturbance was 7.0% greater at scent stations where mink were not detected, the difference was not significant and may therefore indicate that mink may have a tolerance for moderate human disturbances. I also evaluated the performances of 2 types of remote cameras (Moultrie Game Cameras: MGC I–40 and MGC 200) in detecting mink visits at scent stations as well as comparing remote camera detections of mink visits with observations of tracks. The MGC I–40 cameras detected a significantly greater number of mink visits (n = 50) compared to the MGC 200 cameras (n = 3). Detection of mink at scent stations was also significantly greater using the remote cameras compared with observations of mink tracks. Mink were also live–trapped and implanted with subcutaneous radiotransmitters. There were 13 mink captures (0.31 mink/100 trap–nights) with radiotransmitters being implanted in 12 (11 males and 1 female) mink. Overall 166 den sites were located with a mean of 15.9 den sites/mink. Microhabitat analysis of 33 used den sites and 33 unused potentially available den sites (UPADs) indicated that shoreline cover was significantly greater at used den sites. Macrohabitat analysis using 150 m circular buffers surrounding 76 used den sites and 76 unused potentially available sites (UPASs) indicated that human disturbance was 3.3% greater at the UPASs than at used den sites, but this difference was not significant. This may further suggest that mink may have a tolerance for moderate human disturbances. Den site structures most often used by mink included brushpiles or logjams (21.1%) and bank burrows (17.5%). The use of den site structures appeared to be largely based on shoreline cover and availability. The mean linear home range of male mink was 6.6 km (SE = 0.6, range 3.2 – 8.4 km), which was similar to the female's home range of 6.5 km. Ten mink home ranges encompassed portions of both the Hudson River and its tributaries accounting for a mean of 2.8 and 4.4 km, respectively. Mean daily movement distances of mink along shorelines was 659 m (SE = 42, range 0 – 3,087 m) and was significantly greater along tributaries than along the Hudson River.
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Ryherd, Julia Kay. "QUANTIFYING THE RATES AND SPATIAL DISTRIBUTION OF RECENT SEDIMENTATION WITHIN THE HYDROLOGICALLY CONNECTED FLOODPLAINS OF THE MIDDLE MISSISSIPPI RIVER, USA, USING DIGITAL ELEVATION MODELS AND DENDROGEOMORPHOLOGY." OpenSIUC, 2017. https://opensiuc.lib.siu.edu/theses/2189.
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The construction of levees along the Mississippi River [MR], beginning in the mid-to-late nineteenth century, have isolated the river along many segments from its floodplain. Sediment from the river is currently deposited in the hydrologically connected floodplain [HCF], the area between the channel margin at low water and the levees. Researchers have studied the amount and rates of sediment deposition along the Upper and Lower Mississippi River segments from the headwaters to Pool 22 and from the Ohio River to the delta; however, no such assessments have been undertaken along the Middle Mississippi River [MMR]. This study attempts to fill the knowledge gap by assessing sedimentation along three islands within the Middle Mississippi River National Wildlife Refuge. On these islands two approaches were undertaken to assess sedimentation along the MMR’s HCF: dendrogeomorphology and the DEM of Difference [DoD] approach. The dendrogeomorphic approach uses tree-ring analyses to document and interpret geomorphic processes and the rates at which they are occurring. The DoD approach subtracts an older DEM from a newer DEM in order to see the change in elevation/depth over time. The geomorphology of the islands and then the entire MMR HCF (from the confluence of the Missouri River to Thebes, IL) were mapped. Using the sedimentation rates for the geomorphic landforms from the three study islands, the sedimentation rates and volumes for the aforementioned portion of the MMR’s HCF were estimated. The estimated volume of sediment was then compared to the MMR’s suspended sediment flux to determine how much of the suspended sediment was going into storage within the MMR’s HCF. The dendrogeomorphic and DoD methods for the study islands yielded average sedimentation rates of 13.3-16.9 mm year-1 and 21.5-80.1 mm year-1, respectively. The rates for the individual landforms on the islands using the dendrogeomorphic results ranged from 5.2 mm year-1 for the splay to 21.8 mm year-1 for the natural levee and splay, with a weighted average of 16.6 mm year-1 for the MMR HCF. Using these rates and the likely range of densities for the floodplain sediments, it is estimated that 4.9-6.6 million metric tons of sediment is accumulating within the MMR annually. This is approximately 5.4-7.4% of the average annual suspended sediment load of the Mississippi River at St. Louis. This means that the MMR is a major sediment sink. If these relatively rapid rates of deposition continue, they have the potential to substantially reduce the HCF’s ability to convey and store flood water which will result in increased flood levels and, consequently, flood risk within the MMR’s levee protected floodplain in the coming decades.
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Souza, Taciane Silveira. "Preservação do patrimônio arqueológico de fronteira: Museo del Patrimonio Regional de Rivera - Uruguai." Universidade Federal de Pelotas, 2017. http://repositorio.ufpel.edu.br:8080/handle/prefix/3622.
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A pesquisa apresenta os processos interventivos desenvolvidos no acervo histórico e arqueológico do Museo del Patrimonio Regional da cidade de Rivera, Uruguai. As instituições museológicas frequentemente carecem de fundos públicos e de recursos humanos apropriados para a salvaguarda do patrimônio na região, dificultando os projetos expositivos e de curadoria dos acervos. Desta forma, alguns administradores de museus recorrem como alternativa ao estabelecimento de convênios com instituições de estudos e pesquisas, tanto uruguaias como estrangeiras. Como pesquisadora associada ao Laboratório Multidisciplinar de Investigação Arqueológica (LÂMINA – UFPel), e com o apoio do laboratório referenciado, decidimos desenvolver um projeto a fim de melhorar a gestão do acervo do Museo del Patrimonio Regional. A metodologia empregada foi uma adaptação dos procedimentos e critérios utilizados pelo LÂMINA em outras instituições do Brasil e exterior, abrangendo atividades de diagnósticos dos ambientes de acondicionamento e exibição de coleções arquelógicas e históricas; levantamento do estado de conservação das coleções; elaboração e execução de projetos interventivos; acondicionamento e extroversão de coleções; montagem de laboratórios de conservação e restauração; capacitação de profissionais e técnicos e; de musealização de sítios históricos. A realização dessas atividades, conjuntamente com a divulgação das mesmas, colocou, a nosso ver, o museu em outro patamar a nível regional. A valorização das coleções e dos distintos atores sociais envolvidos confirmou-se com outro logro deste projeto
This research presents the interventive processes developed at the collection of the Museo del Patrimonio Regional from Rivera city, Uruguay. Museological institutions frequently are in need of public money and human resources appropriate in order to preserve the regions heritage, making it difficult for expositions and the curatorship of the collections. Thus, some museum administrators resort, as an alternative, to the establishment of partnerships with study and research institutions, both from Uruguay and abroad. As an associated researcher to the Laboratório Multidisciplinar de Investigação Arqueológica (LÂMINA - UFPel), and with the support of this laboratory, we decided to develop a project in order to improve the management of the collection from the Museo del Patrimonio Regional. The employed methodology was an adaptation of the procedures and criterion used by the LÂMINA in other institutions from Brazil and abroad, encompassing activities of diagnosis of the conditioning and display environments for the archaeological and historical collections; an update on the conservation state of the collections; elaboration and execution of interventive projects; storage and extroversion of the collections; creation of laboratories for conservation and restoration; capacitation for professionals and technicians and; musealization of historical sites. The accomplishment of those activities, together with their disclosure, have put, in our opinion, the museum into another regional level. The valuation of the collections and of the different social actors involved was confirmed as another achievement of this project
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Paras, Ben Krisanto Yap, and Ben Krisanto Yap Paras. "Evaluation of Passive Capillary Wick Samplers for Measuring Deep Infiltration at The Jemez River Basin Critical Zone Observatory." Thesis, The University of Arizona, 2017. http://hdl.handle.net/10150/626383.
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Passive capillary wick samplers (PCAPs) are primarily used to sample water from the vadose zone. PCAPs use fiberglass wicks to form a hanging water column that exerts suction on the surrounding soil. Although PCAPs have been used to estimate soil water flux, the accuracy with which PCAPs can estimate flux comes into question due to over/undersampling caused by this applied flux. I used numerical models to explore the effects of a PCAP on flow through the vadose zone. Specifically, I used a two-dimensional axisymmetric flow model of a PCAP embedded in a medium based on HYDRUS. Both steady-state and transient conditions were simulated through the application of various precipitation rates and periods across several soil textures. In this study, I examine soil hydraulic properties, across the soil texture triangle, subject to a range of precipitation events. Results show that the PCAP does over/underestimate water flux. The degree of error is quantified by defining a capture efficiency, which is the ratio of the flux into the plate and the flux that would occur at the same depth with no PCAP present. Higher fluxes and longer time periods resulted in increased convergence of flux into the PCAP, while lower fluxes and shorter durations resulted in divergence of flux from the PCAP. The goal of the study is to understand the behavior of PCAPs under different conditions and to use that knowledge to interpret field measurements in the Jemez River Basin Critical Zone Observatory.
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Vericat, Querol Damià. "Sediment transport and processes in a highly regulated river. The lower Ebro, NE Iberian Peninsula." Doctoral thesis, Universitat de Lleida, 2005. http://hdl.handle.net/10803/8231.
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Aquesta tesi estudia el transport de sediment i els processos fluvials associats al tram baix del riu Ebre al llarg de dos anys hidrològicament mitjans (2002-2004). El transport de sediment, que inclou tant la càrrega de fons com el sediment en suspensió, s'ha mesurat aigües amunt i avall del complex d'embassaments Mequinenza-Riba-roja-Flix. Els canvis morfològics i granulomètrics s'han analitzat aigües avall de la presa de Flix. La càrrega mitjana anual de sediment aigües amunt de les preses és de 1,64·106 tones, de les quals un 99% ho són en suspensió. El transport mig anual aigües avall dels embassaments és de 0,45·106 tones (60% en suspensió i 40% com a càrrega de >fons). Els embassaments retenen al voltant del 95% de la càrrega transportada en suspensió. El transport mitjà anual aigües avall de la presa de Flix representa el 3% del que el riu transportava a l'inici del segle XX en absència d'embassaments. La major part del sediment que el riu transporta actualment prové, per tant, de la pròpia llera, fet que causa una incisió mitjana anual d'uns 30 mm. Una part molt important de la càrrega transportada anualment es produeix durant avingudes d'alta magnitud. Per exemple, el transport aigües amunt de les preses durant les crescudes de febrer i març de 2003 (Q10, 2.600 m3/s) va ser de 1.700.000 tones de sediment. La concentració mitjana de sediment en suspensió durant aquests episodis va ser de 0,5 g/l i la taxa mitjana de càrrega de fons de 100 g/ms. El sediment transportat com a càrrega de fons va representar un 1,5% del total del sediment transportat. Aigües avall de la presa de Flix el riu va transportar 175.000 tones de sediment durant les mateixes crescudes, la meitat com a càrrega de fons. La concentració mitjana de sediment en suspensió fou de 0,05 g/l i la taxa mitjana de càrrega de fons va ser de 150 g/ms. Ambdós modes de transport tenen una gran variabilitat temporal i espacial. La distribució granulomètrica del material del llit està directament controlada per la competència del flux i per la disponibilitat de sediment. Les crescudes d'alta magnitud de 2002-2003 van mobilitzar la cuirassa superficial, incrementant la disponibilitat de sediment (material subsuperficial) i causant una notable incisió de la llera. Contràriament, durant el 2003-2004 el cabal no fou suficientment competent per mobilitzar les fraccions més grolleres i, conseqüentment, el procés dominat fou el de re-acuirassament del llit del riu. Ambdós anys mostren un cicle complert de incisió-acuirassament. Els canvis en la morfologia fluvial aigües avall de la presa de Flix durant la segona meitat del segle XX mostren la pèrdua d'àrees sedimentàries actives (disponibilitat de sediment) degut a la colonització per la vegetació de ribera, i la disminució de l'amplada de la llera (20%), reduint, conseqüentment, la secció activa d'aquesta. La manca de sediment i la reducció de les crescudes controlen els canvis en la morfologia fluvial a mig i llarg termini.Esta tesis estudia el transporte de sedimento y los procesos fluviales asociados en el tramo bajo del río Ebro durante dos años hidrológicamente medios (2002-2004). El transporte de sedimento, que incluye tanto la carga de fondo como el sedimento en suspensión, se ha muestreado aguas arriba y abajo del complejo de embalses Mequinenza-Ribarroja-Flix. Los cambios morfológicos y granulométricos se han analizado aguas abajo de la presa de Flix. La carga media anual de sedimento aguas arriba de las presas es de 1,64·106 toneladas, de las cuales un 99% lo son en suspensión. El transporte medio anual aguas abajo de los embalses es de 0,45·106 toneladas (60% en suspensión y 40% como carga de fondo). Los embalses retienen alrededor del 95% de la carga en suspensión. El transporte medio anual aguas abajo de la presa de Flix representa el 3% de lo que el río transportaba al principio del siglo XX en ausencia d'embalses. La mayor parte del sedimento que el río transporta actualmente proviene, por lo tanto, del propio cauce, hecho que causa una incisión media anual de 30 mm. Una parte muy importante de la carga transportada anualmente lo es durante avenidas de alta magnitud. Por ejemplo, el transporte aguas arriba de las presas durante las crecidas de febrero y marzo de 2003 (Q10, 2.600 m3/s) fue de 1.700.000 toneladas de sedimento. La concentración media de sedimento en suspensión durante estos episodios fue de 0,5 g/l y la tasa media de carga de fondo de 100 g/ms. El sedimento transportado como carga de fondo representó un 1,5% del total del sedimento transportado. Aguas abajo de la presa de Flix el río transportó 175.000 toneladas de sedimento durante las mismas crecidas, la mitad como carga de fondo. La concentración media de sedimento en suspensión fue de 0,05 g/l y la tasa media de carga de fondo fue de 150 g/ms. Ambos modos de transporte tienen una gran variabilidad temporal y espacial. La distribución granulométrica del material del lecho está directamente controlada por la competencia del flujo y por la disponibilidad de sedimento. Las crecidas de alta magnitud de 2002-2003 movilizaron la coraza superficial, incrementando la disponibilidad de sedimento (material subsuperficial) y causando una notable incisión del cauce. Contrariamente, durante 2003-2004 el caudal no fue suficientemente competente para movilizar las fracciones más gruesas y, consecuentemente, el proceso dominante fue el de re-acorazamiento del lecho del río. Ambos años muestran un ciclo completo de incisión-acorazamiento. Los cambios en la morfología fluvial aguas abajo de la presa de Flix durante la segunda mitad del siglo XX muestran la pérdida de áreas sedimentarias activas (disponibilidad de sedimento) debido a la colonización por vegetación de ribera, y la disminución de la anchura del cauce (20%), reduciendo, como consecuencia, la sección activa. La falta de sedimento y la reducción de las crecidas controlan los cambios en la morfología fluvial a medio y largo plazo.
The sediment transport and the associated fluvial processes have been analysed in the large impounded lower Ebro River during two representative hydrological years (2002-2004). Sediment transport, including both suspended and bedload, have been measured upstream and downstream the Mequinenza-Riba-roja-Flix reservoirs chain. Fluvial adjustments have been monitored downstream from the Flix Dam. Results indicate that the mean annual total load upstream from the dams is estimated at 1.64·106 tonnes, of which more than 99% is transported in suspension. The mean annual total load below the dams is estimated at 0.45·106 tonnes, of which 60% is transported in suspension and 40% as bedload. Reservoirs retain up to 95% of fine sediments transported by the river. Total load represents 3% of what was transported at the beginning of the 20th century in the absence of dams. Nowadays, sediment load downstream from the dams is almost all entrained from the riverbed, causing a mean riverbed incision of 30 mm per year. Sediment transport was particularly high during floods. Around 1,700,000 tonnes were transported upstream from the dams during the February and March 2003 floods (Q10 with a peak discharge of 2,600 m3/s), with mean suspended sediment concentrations of 0.5 g/l and mean bedload rates of 100 g/ms. Bedload represented approximately 1.5% of the total load. In contrast, 175,000 tonnes were transported at the downstream monitoring section, with mean suspended sediment concentrations of 0.05 g/l and mean bedload rates of 150 g/ms, showing a high degree of temporal and spatial variability. Bedload represented approximately half of the total load. The grain-size distribution of the riverbed materials has shown to be strongly related to flow competence and sediment availability. On one side, high competent discharges during 2002-2003 were able to entrain most coarse surface material (i.e., armour layer), increasing the availability of sediment to be transported (subsurface material), causing remarkable incision. On the other, discharges during 2003-2004 were not competent to move coarse particles and a re-armouring process occurred. Both years, including five natural floods and two flushing flows, have shown a complete incision-armouring cycle. Riverchannel adjustments during the second half of the 20th century include the loss of active sedimentary areas, hence sediment availability, due to vegetation encroachment (i.e. riparian forest), and channel narrowing (20%), thus reducing the active section of the channel. The lack of sediment transport and the reduction of frequent floods below the dams control the medium and long-term changes observed in river's channel morphology.
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Weakley, Jacob. "Late Holocene Chronoclinal Variation in White-tailed Deer (Odocoileus Virginianus) Associated with Human Behavior in the Ohio River Valley." University of Cincinnati / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1627662816219324.
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Long, Nguyen Tien. "Sustainabilty assessment of vegetable cultivation systems in the Red River Delta, Vietnam." Doctoral thesis, Humboldt-Universität zu Berlin, Landwirtschaftlich-Gärtnerische Fakultät, 2013. http://dx.doi.org/10.18452/16763.
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Zur Einschätzungen und Bewertung der Nachhaltigkeit der gegenwärtigen Gemüseproduktion im Roten-Fluss-Delta, Vietnam, erfolgten empirische Untersuchungen zur Ermittlung und Bewertung eines Nachhaltigkeitsindex unter Nutzung verschiedener Lösungsansätze. Die Analysen und Einschätzungen wurden aus ökologischer ökonomischer und sozialer Sicht vorgenommen. Die erfassten Daten wurden unter Nutzung von zwei Methoden ausgewertet, der Mehr-Kriterien-Bewertungsmethode Analytic Hierarchy Process (AHP) und der Fuzzy Bewertungsmethode. In Workshops wurden mit den Farmern Präferenzen als Element der AHP, zu den Kriterien die Ausdruck der Nachhaltigkeit sind, erarbeitet. Es wurde herausgearbeitet, dass im ländlichen Raum, die Gemüseproduktion nachhaltig ist, im Peri-urbanen Raum wurde eine geringe Nachhaltigkeit ermittelt und im urbanen Raum keine Nachhaltigkeit. Im Ergebnis der Forschungsarbeit wurde herausgearbeitet, dass für einen nachhaltigen Gemüse-Anbau im Roten-Fluss-Delta, die Farmer ihr Kontrollsystem und System der Nachverfolgbarkeit verbessern müssen. Gleichermaßen ist es erforderlich die sozialen Bedingungen so zu gestalten, das die Prinzipien der‚ Guten Landwirtschaftlichen Praxis‘ greifen. Im Rahmen der Forschungsarbeit konnte gleichfalls eine Bewertung der Nachhaltigkeit unter Nutzung der Fuzzy Methode erfolgreich eingesetzt werden. Diese Ergebnisse sind geeignet, sowohl den Farmern, als auch den politischen Entscheidungsträgern, die geeigneten Werkzeuge für die Entwicklung einer nachhaltigen Gemüse Kultivierung in der Zukunft zu geben.This study is empirical research by applying different sustainability assessment approaches to evaluate and to compare the sustainability index of the existing vegetable cultivation systems in the Red River Delta - the largest vegetable production land area of Vietnam in terms of environment, economic and social dimensions. In addition, this study also incorporated farmers'' perceptions as well as their preferences into the weight of criteria by using Analytic Hierarchy Process (AHP) in multi-criteria evaluation method, and rules formed in fuzzy evaluation method. The results from the sustainability assessment for the vegetable cultivation systems show that in the rural area, the sustainability are acceptable whereas in the peri-urban area are only conditionally acceptable, and in the urban area are not sustainable. The results from this study indicate that, to achieve sustainable vegetable cultivation systems in the Red River Delta in Vietnam, the farmers need improved internal controls and tracing systems as well as strict social control in order to implement good agricultural practices guidelines. This study result also shows that the sustainability assessment by fuzzy evaluation approach appears to be well suited to provide quantitative answers pertaining to sustainability that can help policy maker in choosing the tool for sustainability assessment in the future.
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Gómez, Acuña Luis. "Peralta Rivera, Germán. Los mecanismos del comercio negrero. Kuntur Editores, Lima 1990, 391 p." Pontificia Universidad Católica del Perú, 2014. http://repositorio.pucp.edu.pe/index/handle/123456789/121524.
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Montalbetti, Mario. "M,L. Rivero, Estudios de Gramática Generativa del Español, Madrid (Ediciones Cátedra), 1977, 161 pp." Pontificia Universidad Católica del Perú, 2013. http://repositorio.pucp.edu.pe/index/handle/123456789/101476.
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Conradt, Tobias. "Challenges of regional hydrological modelling in the Elbe River basin : investigations about model fidelity on sub-catchment level." Phd thesis, Universität Potsdam, 2013. http://opus.kobv.de/ubp/volltexte/2013/6524/.
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Within a research project about future sustainable water management options in the Elbe River basin, quasi-natural discharge scenarios had to be provided. The semi-distributed eco-hydrological model SWIM was utilised for this task. According to scenario simulations driven by the stochastical climate model STAR, the region would get distinctly drier. However, this thesis focuses on the challenge of meeting the requirement of high model fidelity even for smaller sub-basins. Usually, the quality of the simulations is lower at inner points than at the outlet.
Four research paper chapters and the discussion chapter deal with the reasons for local model deviations and the problem of optimal spatial calibration. Besides other assessments, the Markov Chain Monte Carlo method is applied to show whether evapotranspiration or precipitation should be corrected to minimise runoff deviations, principal component analysis is used in an unusual way to evaluate local precipitation alterations by land cover changes, and remotely sensed surface temperatures allow for an independent view on the evapotranspiration landscape.
The overall insight is that spatially explicit hydrological modelling of such a large river basin requires a lot of local knowledge. It probably needs more time to obtain such knowledge as is usually provided for hydrological modelling studies.Innerhalb eines Forschungsprojekts zu zukünftigen nachhaltigen Optionen der Wasserwirtschaft im Elbe-Einzugsgebiet mußten quasi-natürliche Abflußszenarien bereitgestellt werden. Zu diesem Zweck wurde das räumlich diskretisierte ökohydrologische Modell SWIM eingesetzt. Nach den von dem stochastischen Klimamodell STAR angetriebenen Szenariosimulationen würde die Region deutlich trockener werden. Allerdings ist das Hauptthema dieser Dissertation die Herausforderung, die Ansprüche an hohe Modelltreue auch für kleinere Teileinzugsgebiete zu erfüllen. Normalerweise ist die Qualität der Simulationen für innere Punkte geringer als am Gebietsauslaß. Vier Fachartikel-Kapitel und das Diskussionskapitel beschäftigen sich mit den Gründen für lokale Modellabweichungen und dem Problem optimaler räumlicher Kalibrierung. Unter anderem wird die Markovketten-Monte-Carlo-Methode angewendet, um zu zeigen, ob Verdunstung oder Niederschlag korrigiert werden sollte, um Abweichungen des Abflusses zu minimieren, die Hauptkomponentenanalyse wird auf eine unübliche Weise benutzt, um lokale Niederschlagsänderungen aufgrund von Landnutzungsänderungen zu untersuchen, und fernerkundete Oberflächentemperaturen erlauben eine unabhängige Sicht auf die Verdunstungslandschaft. Die grundlegende Erkenntnis ist, daß die räumlich explizite hydrologische Modellierung eines so großen Flußeinzugsgebiets eine Menge Vor-Ort-Wissen erfordert. Wahrscheinlich wird mehr Zeit benötigt, solches Wissen zu erwerben, als üblicherweise für hydrologische Modellstudien zur Verfügung steht.
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Ayuk, James Ayuk. "Modelling of nonpoint source pollution in the Kuils River Catchment, Western Cape - South Africa." Thesis, University of the Western Cape, 2008. http://hdl.handle.net/11394/3131.
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Della, Fera Stefano. "Il ruolo di un atmospheric river nell'evento di precipitazione estrema dell'ottobre 2018 in Italia." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/18809/.
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Studi recenti evidenziano una stretta correlazione esistente tra gli eventi di precipitazione estrema e la presenza di atmospheric river (AR). Si tratta di estese strutture filamentose di concentrazione anomala di vapore acqueo collocate nei primi 3 km della troposfera e legate alla formazione di un intenso low-level jet posizionato davanti al fronte freddo di un ciclone extra-tropicale. Gli effetti degli AR sulle precipitazioni sono stati ampiamente descritti in letteratura limitatamente alla West Coast americana, alle regioni lungo le coste atlantiche europee e recentemente al Giappone e all'India.
Nel seguente lavoro di tesi viene individuata per la prima volta nel bacino del Mediterraneo la presenza di un AR che ha condizionato in modo determinante l'intenso evento meteorologico del 27-30 ottobre 2018 in Italia.
Le simulazioni numeriche effettuate con il modello numerico meteorologico BOLAM e l'utilizzo di specifici algoritmi hanno permesso di individuare l'AR, il quale trasporta vapore acqueo dall'Atlantico sub-tropicale, attraverso il continente africano, transitando sull'Algeria fino al Mediterraneo centrale lungo una traiettoria di circa 3000 km.
Inoltre, l'utilizzo di una specifica diagnostica per il calcolo del budget di acqua in atmosfera ha consentito una caratterizzazione quantitativa del ruolo dell'AR e degli altri contributi di umidità presenti sul Mediterraneo.
A questo proposito, è stato valutato l'impatto dell'evaporazione dal mare sulle piogge sul Nord e Centro Italia, attraverso un confronto con i contributi di umidità trasportati da sorgenti remote. Questa analisi è stata approfondita mediante l'utilizzo di esperimenti numerici di sensibilità.
Infine, è stato evidenziato il possibile impatto dell'AR sulla ciclogenesi esplosiva osservata sul Mediterraneo, che ha caratterizzato la seconda fase dell'evento.
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Burfeid, Castellanos Andrea Montserrat. "Ecological factors and diatom diversity at rivers of the iberian mediterranean river basins: macro-scale, meso-scale and micro-scale = Factores ecológicos y diversidad de diatomeas en los ríos de las cuencas hidrográficas del Mediterráneo ibérico: maro-escala, meso-escala y micro-escala." Doctoral thesis, Universitat de Barcelona, 2018. http://hdl.handle.net/10803/663475.
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Benthic diatoms, photoautotrophic, silicate plated, single-celled aquatic organisms dwelling on substrates, have been used in bioindication, since they are good indicators of ecological water state. In this thesis, we have used a multi-scalar approach to observe how diatoms from Spanish Mediterranean rivers are affected by the characteristics of the habitats they live in. These organisms were observed under a taxonomic-indicative, functional-grouped and morphometric prism.
The samples stem from Mediterranean rivers pertaining to either the Ebro Basin, or jurisdictions of the Catalan rivers or the Júcar authorities. Ebro samples have a fundamental importance, due to their temporal frame of 10 years, which has permitted the establishment and observation of changes in diatom communities and their characteristics. Two experimental setups, comparing differing water compositions and hydrological characteristics, were made in the other basins. The structure of this thesis takes a gradual decrease in observation range.
The macro-scale: chapter studied benthic diatom communities from the Ebro River Basin taxonomically, based on samplings ranging 10 years. We studied if diatom communities were maintained in time, or what parameters could help to the establishment of ecoregions. This study showed that the ecotype division of rivers established by the Water Framework Directive (WFD) did not reflect diatom assemblages well. A double approach of physico- chemical and diatom-sociological aggregation can create a better mirror of diatom communities, thus improving ecoregions for diatoms.
The meso-scale chapter investigated the Segre, Ebro tributary, observing the relationship between land use and diatom assemblages and indicator values. Land uses have a direct effect on river water composition. Thus, a link between upstream land cover and diatom assemblages was expected. The results show that only the predominant covers affect both the composition of the diatom community and indicator values. Structural Equation Modelling comparisons have established changes in the importance of physicochemical parameters through time and depending on diatom community structure. Diversity indices and bioindicator values were affected mostly by physicochemical composition, and tangentially by land cover.
In the micro-scale chapter, the reaction of diatoms at each site was studied. To do this, we parted the chapter in three sections, two life form experiments to observe how physicochemical composition and hydrology affect life forms, and how morphometry can be affected through abiotic parameter variation in time. The first, made in the Llobregat Basin, was an experimental approach to ascertain the effect of intrinsically different sites on diatom life forms and ecological guilds and the change when these communities are translocated. This showed that, although the physicochemical parameters seemed to favour functional groups, changing the community into a different site could still maintain some of the characteristic life forms.
Then, a comparison of functional structure of the diatom community in temporary rivers (that lose part or the totality of its surface water) of Mediterranean basins along the northeast coast was made. It showed that the hydrological regime (connectedness of the stream in total) had a bigger impact than aquatic state (water quantity
present at time of sampling). The disconnection of streams also affected the use of conventional diatom bioindicators that will be addressed in the future.
Finally, in this microscale prism, we automatically photographed samples from the Ebro River to extract diatom morphometry features. Relating these to physicochemical parameters of each site and their temporal variability, we saw that diatom sizes are affected by water composition. The surface-to-volume ratio (S/V) was highly correlated. An up to now neglected parameter, diatom width, was highly affected by physicochemical parameters.
This thesis attempted to establish how diatoms and their traits are affected by their surroundings, observing the effect of abiotic parameters, such as physicochemical composition, land use, and substrate characteristics.Las diatomeas bentónicas son organismos fotoautotróficos unicelulares, acuáticos y colonizadores de sustratos, que se han usado en bioindicación por ser buenas indicadoras del estado ecológico del agua. En esta tesis hemos estudiado cómo las diatomeas de ríos ibéricos mediterráneos se ven afectadas por la ecología del medio donde habitan, a diversas escalas. Estos organismos se estudiaron a nivel taxonómico e indicativo, funcional y morfométrico. La estructura de esta tesis sigue una aproximación a la reducción de escala de trabajo. El capítulo de macro-escala se basó en una investigación de las comunidades bentónicas epilíticas de las diatomeas del río Ebro, en base a muestreos realizados a lo largo de 10 años. Este estudio se ha demostrado que la división en ecotipos fluviales establecida para el seguimiento de la Directiva Marco del Agua (DMA) no coincide con la diversificación delascomunidades deestosorganismos. Nuestrosresultados apuntanqueunaaproximacióndoble (composición físico-química y estructura de la comunidad) puede reflejar mejor la realidad para las diatomeas. En el capítulo de meso-escala se investigó el río Segre con la finalidad de establecer las relaciones entre los usos del suelo y las comunidades de diatomeas y valores de los índices de diatomeas. Los usos del suelo afectan directamente a la composición del agua fluvial. Por ello, se esperaba una correlación entre el uso del suelo aguas arriba de las comunidadesde diatomeas estudiadas. Los resultados muestranque únicamentelos usos mayoritarios afectan la composición las comunidades de diatomeas y los valores de los índices diatómicos. En el capítulo de microescala se estudió la reacción de las diatomeas en cada punto. Para ello el capítulo se dividió en tres secciones. Un experimento observó el efecto de puntos intrínsecamente diferenciales sobre las formas de vida, y cambios de estas tras su translocación. La otra sección comparó la composición funcional de la comunidad de diatomeas en ríos temporales, que sufren pérdida parcial o total del agua superficial. Finalmente, aún en microescala, se fotografiaron automáticamente muestras de diatomeas del río Ebro para calcular sus características morfométricas. Estas se relacionaron con los parámetros fisicoquímicos de cada punto y con su variabilidad temporal. El resultado fue una clara afectación de tamaños valvares según la composición del agua. La relación superficie-volumen estaba altamente correlacionada y la anchura valvar, obviada hasta ahora, se vio afectada por los parámetros fisicoquímicos.
Les diatomees bentòniques, organismes fotoautotròfics unicel·lulars, aquàtics i colonitzadors de substrats, que s’han utilitzat a la bioindicació per ser bones indicadores del estat ecològic de l’aigua. En aquesta tesi hem estudiat com les diatomees de rius ibèrics mediterranis es veuen afectades per l’ecologia del medi al que habiten a diverses escales. Aquests organismes es varen observar a nivell taxonòmic-indicatiu, funcional i morfomètric. L’estructura d’aquesta tesi segueix una aproximació a la reducció d’escala de treball. El capítol de macro-escala es basà en una investigació taxonòmica de les comunitats bentòniques epilítiques de diatomees del riu Ebre, basat en mostrejos realitzats al llarg de 10 anys. Aquest estudi ha mostrat que la divisió d’ecotips fluvials establerta per a el seguiment de la Directiva Marc de l’Aigua (DMA) no coincideix amb la diversificació de les comunitats d’aquests organismes. Els resultats assenyalen que una aproximació doble (composició fisicoquímica i estructura comunitària) podria reflectir millor la realitat per a les diatomees. Al capítol de meso-escala s’estudià el Segre per tal d’establir les relacions entre els usos del sòl, les comunitats de diatomees i els seus valors indicadors. Els usos del sòl afecten directament a la composició de l’aigua fluvial. Per això, s’esperava una correlació entre els usos del sòl aigües amunt de les comunitats de diatomees estudiades. Els resultats mostren que únicament els usos majoritaris afecten els la composició de les comunitats de diatomees els i valors dels índexs diatòmics. El capítol de micro-escala investigà la reacció de les diatomees a cada punt. Per això, el capítol es dividí en tres seccions. Un experiment observà l’efecte de punts intrínsecament diferencials sobre les formes de vida i canvis d’aquests després de la translocació. L’altra secció comparà la composició funcional de la comunitat de diatomees a rius temporals, que pateixen la pèrdua total o parcial de l’aigua superficial. Finalment, seguint a la micro-escala, es fotografiaren les mostres del riu Ebre automàticament per calcular les seves característiques morfomètriques. Aquestes es relacionaren amb els paràmetres fisicoquímics de cada punt i la seva variabilitat temporal. El resultat fou una clara afectació de mides valvars segons la composició de l’aigua. La relació superfície-volum estava altament correlacionada amb les variacions fisicoquímiques i l’amplada valvar, obviada fins ara, era afectada pels paràmetres fisicoquímics.
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Bangash, Rubab Fatima. "Analysis of climate change impact on hydrological ecosystem services and water allocation in water scarce mediterranean river basins." Doctoral thesis, Universitat Rovira i Virgili, 2014. http://hdl.handle.net/10803/145256.
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The Mediterranean region appears to be particularly responsive to global and climate change, causing decrease in annual river flows and making the region most prone to an increase in drought hazard and water stress. This thesis is an approach to quantify and analyse the water quantity, hydrological ecosystem services and water supply in temperate regions under environmental changes. Hydrological flow and hydrological ecosystem services (water provisioning) models are developed for a low flow Mediterranean river (Francolí river) basin using MIKE BASIN and InVEST respectively. Changes in the delivery of regulating (erosion control) services are also assessed in the heavily humanized Llobregat River basin (NE Spain) considering drivers of climate change (temperature and precipitation). Moreover, Analytic Hierarchy Process (AHP) is adapted to solve the multi-criteria decision-making problem of alternate water supply for different sectors in Francolí river basin. Climate change have already affected some elements of hydrological ecosystem services and that some are vulnerable in the Mediterranean river basins. Together these effects determine the need of a correct approach for water allocation system and the appropriate alternate water resources at a catchment level due to water scarcity.Parece ser que la región mediterránea esuna zona particularmente vulnerable al cambio global y climático. Este hecho provoca un descenso en el caudal anual de los ríos y que la zona sea más propensa a un aumento de las sequías y el estrés hídrico. Esta tesis es una aproximación a la cuantificación y el análisis de la cantidad de aguay de los servicios ecosistémicos hidrológicos en regiones templadas bajo cambios ambientales.Se desarrollaron los modelos de caudal hidrológico y servicios ecosistémicos hidrológicos (aprovisionamiento de agua) para una cuenca de río mediterráneo de bajo caudal (río Francolí) utilizando MIKE BASIN e InVEST respectivamente. También se evaluaron los cambios en el subministro del serviciode regulación (control de la erosión) en la cuenca del río Llobregat (NE de España), la cual está fuertemente humanizada, considerando los impactos del cambio climático (temperatura y precipitación). Además, se adaptó el Proceso Jerárquico Analítco (PJA) para solucionar el problema de la alternativa de disponibilidad de agua para diferentes sectores en la cuenca del río Francolí según múltiples criterios de decisión. El cambio climático ya ha causado impactosen algunos elementos de los servicios ecosistémicos hidrológicos que son vulnerables en las cuencas de ríos mediterráneos. Todos estosimpactos determinan que, debido a la escasez de agua, sea necesario un enfoque correcto para el sistema de asignación de agua y los recursos hídricos alternativos apropiados a nivel de cuenca.
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Ortiz, Lerín Roser. "Diatomees de la conca de l’Ebre: Biodiversitat i estat ecològic de l’aigua." Doctoral thesis, Universitat de Barcelona, 2011. http://hdl.handle.net/10803/83471.
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Els resultats que es presenten en aquesta tesi estan centrats bàsicament en l'estudi de la biodiversitat de les diatomees epilítiques presents en els rius de la conca de l'Ebre i en la seva aplicació com a indicadores de l'estat ecològic de les masses d'aigua.
Durant els mesos d'estiu del 2005 i 2006 es va realitzar el mostreig de la flora de diatomees epilítiques en un total de 197 i 211 estacions, respectivament, pertanyents a la Xarxa de Control de l'Estat de les Masses d'Aigües Superficials (CEMAS) de la Confederació Hidrogràfica de l'Ebre (CHE). Aquests mostrejos van ser impulsats per la CHE amb l'objectiu d'establir xarxes de control biològic, basades en bioindicadors del fitobentos per tal de conèixer l'estat ecològic de les aigües fluvials d'acord amb el que estableix la Directiva Marc de l'Aigua (DMA).
La recollida de les mostres, el seu tractament químic i, la quantificació de les espècies per localitat, s'han basat en les normatives estandarditzades europees CEN/TC 230 EN 13946:2003, norma prEN 14407: 2004 i, en els protocols de la CHE per l'avaluació de la qualitat biològica en rius mitjançant diatomees.
L'examen de les mostres recollides ha permès la identificació de 499 tàxons, repartits en 91 gèneres, dels quals 492 han estat a nivell específic o infra-específic. Dels tàxons identificats, 361 estan representats en 751 fotografies realitzades al microscopi òptic, agrupats en 25 làmines.
Com a particularitats de la flora s'esmenta d'una banda la presència de 7 espècies al•lòctones segons les consideracions principalment de Coste & Ector 2000 Achnanthidium catenatum, A. druartii, Diadesmis confervacea, Didymosphenia geminata, Gomphoneis minuta, Navicula kotschyi y Reimeria uniseriata) i per l'altre, la presència en algunes localitats de diverses formes teratològiques que podrien indicar condicions adverses del medi (estrès químic o contaminació), encara que en alguns casos podrien ser originades simplement per causes naturals.
Com a resultat de la determinació de l’estat ecològic de les masses d’aigua s'ha comprovat l'aplicació i funcionament òptim dels índexs de diatomees (Index de Pol•lució Específica IPS, Index Biològic de Diatomees IBD i Index Europeu CEE), sent l'IPS l'índex més convenient per la bioindicació de l'aigua a la conca de l'Ebre. No obstant, aquests índexs no reflecteixen prou bé les diferències entre algunes ecoregions de la conca de l'Ebre, com ara les capçaleres calcàries.
Tenint en compte els resultats obtinguts amb l'IPS, la proporció de localitats estudiades que complirien amb la DMA en aquests 2 anys d'estudi són bastant similars, seria del <62% pel 2005 i del <64% pel 2006.
Els resultats de l'índex de Shannon & Weaver indiquen que la diversitat i la riquesa específica s'ajusta a un model relacionat amb la qualitat del medi. Les correlacions d'aquests paràmetres respecte a variables ambientals (pH, conductivitat, clorurs, amoni, fosfats, nitrats, TSS, oxigen dissolt, altitud de la localitat, corrent, amplada i fondària del riu) i els resultats dels índexs de diatomees (IPS, IBD i CEE) mostren que la diversitat de les comunitats de diatomees en les localitats estudiades augmenta quan empitjora l'estat ecològic, seguint un gradient marcat principalment per l'altitud i la concentració de nutrients.
L'estudi de l'ordenació de les comunitats de diatomees epilítiques en els rius de la conca de l'Ebre, tenint en compte les variables ambientals de les localitats estudiades, mostra que la seva distribució seguiria un gradient capçalera-desembocadura, marcat per l’increment progressiu de la mineralització en el que se superposen els efectes de les variables ambientals que es relacionen amb els impactes i els nutrients.
Les anàlisis clúster dels inventaris seleccionats distingeixen 7 grups de localitats i 6 grups ecològics diferents de diatomees que responen a les pertorbacions observades i als gradients de mineralització i eutròfia que caracteritzen la conca de l'Ebre."Diatoms of the Ebro basin: Biodiversity and ecological state of water" TEXT: The aim of this PhD thesis is to contribute to the taxonomic knowledge of the epilithic diatom flora from the rivers of the Ebro basin and to determinate the water quality status in the studied area using benthic diatoms as indicators. The studied area is located inside the Water Quality Surveillance Network of the Ebro Water Agency, CHE (NE Spain). It includes the Ebro and Garona rivers and all the rivers and streams which run into them in the Spanish territory, mostly over a calcareous and sedimentary substrata. A total of 408 epilithic diatoms samples were collected from different environments and ecoregions within the limits of the network of the Ebro Water Agency, CHE (NE Spain) during the summers of 2005 (197 sites) and 2006 (211 sites). Epilithic diatom were sampled, and then treated to prepare permanent diatoms slides following the standard methods (European Committee for Standardization 2003, 2004). The number of taxa identified in the material studied amounted to 499 (492 a specific or infra specific level), belonging to 91 different genera. 361 taxa are presented in 751 light microscope micrographs regrouped in 25 plates. We noticed the presence of species considered rare or exotic for European freshwaters (Coste & Ector, 2000) such as Diadesmis confervacea; Achnanthidium catenatum, Reimeria uniseriata, Navicula kotschyi, Gomphoneis minuta and Didymosphenia geminata. A few diatoms species presented teratological forms have been detected in some localities. However, we could not find a direct relationship of these forms occurrence and any particular cause. In order to evaluate the water quality assessment, three diatoms indices were applied (Specific Pollution Index IPS, Biological Diatom Index BDI and European Index CEC). All of them correlated significantly with water physical and chemical variables, but SPI achieved better correlations, and is therefore to be the best diatom index to be applied in the Ebro basin, although in some cases it did not properly reflected special situations in this basin as calcareous headwaters. According to the cluster and canonical correspondence analyses, nutrient enrichment (from the headwaters to the mouth), environmental variables and impacts were to be the most important variables structuring diatom communities in the Ebro basin.
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Mendoza, Martínez Edison. "A Paracas Ceramic Sequence From Pallauca, Vilcashuamán-Ayacucho." Pontificia Universidad Católica del Perú, 2017. http://repositorio.pucp.edu.pe/index/handle/123456789/113532.
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This article presents the results of excavations carried out at the Formative Period site of Pallaucha, located south of Ayacucho, in the basin of the Pampas River. Until recently, Ayacucho was considered a minor area during the Formative Period; however, this idea could change thanks with the discovery of complex architecture associated to cultural materials coming from different area; one of them the South Coast. Three ceramic phases were identified during excavations at Pallaucha, which suggests a close relationship between this site and the South Coast. In this paper we describe the associated contexts.El presente artículo expone los resultados obtenidos de las excavaciones en el sitio del Periodo Formativo Pallaucha, ubicado al sur de Ayacucho, en la cuenca del río Pampas. Hasta hace pocos años, Ayacucho se consideraba como un área sin mucha importancia durante el Periodo Formativo; sin embargo, las últimas evidencias podrían cambiar esa imagen, ya se ha encontrado arquitectura monumental compleja asociada a material cultural procedente de diversas áreas; una de ellas es la Costa Sur. Materiales procedentes de esta parte de la costa peruana son importantes, no solo porque la costa de Paracas se halla relativamente cerca de Ayacucho, sino porque aparecen en todos los sitios del Periodo Formativo. Durantelas excavaciones en Pallaucha, se ha encontrado secuencia de tres fases de cerámica Paracas, lo que sugiere relaciones estrechas con la Costa Sur. En este trabajo, describiremos sus contextos asociados.
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López-Castaño, Carlos E., and Martha C. Cano-Echeverri. "Considerations About The First Settlements In Northwestern South America: Approaches From The Inter-Andean Magdalena River Valley, Colombia." Pontificia Universidad Católica del Perú, 2014. http://repositorio.pucp.edu.pe/index/handle/123456789/113602.
Full textAbstract:
This article presents key data and discussion about the initial peopling of northwestern South America, highlighting its strategic significance in the continental context, cultural variability and landscape change over time. In Colombia there is very little relevant information regarding occupations prior to 12,000 BP; in contrast, the information is abundant relative to a number ofearly contexts during the Pleistocene-Holocene transition. The variability among unifacial and bifacial lithic assemblages reported in different physiographic regions indicates alternative models on early settlement to regional level. Considering the importanceof the inter-Andean valley of the Magdalena River, this article emphasizes the archaeological contexts and paleoenvironmental information, highlighting environmental impacts associated not only to global climate change, but in particular of the effects ofvolcanism. The article stresses the findings and chronologies of bifacial lithic assemblages of the Magdalena Valley in relation to the early archaeology of northwestern South America.En este artículo se presentan los principales datos y reflexiones asociados al poblamiento inicial del noroccidente de Sudamérica debido a su significado estratégico en el marco continental, se destacará la variabilidad cultural y se enfatizarán los cambios depaisajes en el transcurso del tiempo. En Colombia existe muy poca información relevante relacionada con las ocupaciones anterioresa 12.000 AP; en contraste, la información es abundante en cuanto al número de contextos tempranos durante la transición Pleistoceno-Holoceno. La variabilidad entre los conjuntos líticos unifaciales y bifaciales reportados en distintas regiones fisiográficas plantea propuestas de modelos alternativos sobre el poblamiento temprano a escala regional. Considerando la importancia del valle interandino del río Magdalena, se recalcan los contextos arqueológicos e información paleoambiental. Asimismo, se destacan los impactos ambientales que demuestran por qué no perduraron las evidencias del Pleniglacial, lo que podría deberse a efectos asociados no solo al cambio climático global, sino, en particular, a causa del vulcanismo. Este trabajo resalta los hallazgos y cronologías de los conjuntos líticos bifaciales del valle del Magdalena en relación con la arqueología temprana del noroccidente de Sudamérica.
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Bilderback, Eric Leland. "Hillslope response to climate-modulated river incision and the role of deep-seated landslides in post-glacial sediment flux: Waipaoa Sedimentary System, New Zealand." Thesis, University of Canterbury. Geological Sciences, 2012. http://hdl.handle.net/10092/7439.
Full textAbstract:
Quantifying how hillslopes respond to river incision and climate change is fundamental
to understanding the geomorphic evolution of tectonically uplifting landscapes during
glacial-interglacial cycles. Hillslope adjustment in the form of deep-seated bedrock
landslides can account for a large proportion of the regional sediment yield and
denudation rates for rapidly uplifting landscapes. However, the timing and magnitude of
the response of hillslopes to climatic and tectonic forcing in moderate uplift temperate
maritime catchments characteristic of many active margins worldwide is not well
quantified. This study seeks to investigate how hillslopes respond to climate-modulated
river incision and to quantify the magnitude of the sediment flux from this response in a
typical active margin setting.
The non-glacialWaipaoa Sedimentary System (WSS) on the East Coast of the North
Island of New Zealand consists of river catchments, coastal foothills to uplifting
mountain ranges, and terrestrial and marine sediment depocentres collectively underlain
by relatively young (Cretaceous and younger) sedimentary rocks within a tectonically
active setting and temperate maritime climate. These attributes make theWSS similar to
many coastal catchments on oceanic-continental convergent margins worldwide.
However, because of widespread destruction of primary forests for conversion to pasture
lands by the mid 20th Century, theWSS is currently a globally significant source of
sediment to the world’s oceans. Because of these factors, theWSS was selected as one of
two global study sites for the international, NSF supported, MARGINS Source-to-Sink
initiative designed to investigate the transfer of sediment from terrestrial source to
marine sink. Previous studies on theWSS have shown a strong link between climate
change and geomorphic response in the system. River incision since the last glacial
coldest period has generated a significant amount of topography, leaving small remnants
of the ca.18,000 cal. yr BP last glacial aggradation terrace scattered up to 120 m above
modern rivers.
In this study, the hillslope response to river incision is quantitatively examined using new
high resolution topographic data sets (lidar and photogrammetry) in combination with
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field mapping and tephrochronology. Hillslopes are found to be coupled to river incision
and adjusted to rapid incision through the initiation and reactivation of deep-seated
landslides. In the erodible marine sedimentary rocks of the terrestrialWSS, post-incision
deep-seated landslides can occupy over 30% of the surface area. Many of these slides
show evidence of multiple “nested” failures and landslide reactivation. The ages of
tephra cover beds identified by electron microprobe analysis show that following an
initial 4,000 to 5,000 year time lag after the initiation of river incision, widespread
hillslope adjustment started between the deposition of the ca. 13,600 cal. yr BPWaiohau
tephra and the ca. 9,500 cal. yr BP Rotoma tephra. Tephrochronology and geomorphic
mapping analysis indicates that river incision and deep-seated landslide slope adjustment
is synchronous between mainstem rivers and headwater tributaries. Tephrochronology
further shows that many slopes have continued to adjust to channel incision into the late
Holocene. Hillslope response in the catchment can involve the entire hillslope from river
to ridgeline, with some interfluves between incising sub-catchments being dramatically
modified through ridgeline retreat and/or lowering. Using the results of the landform
tephrochronology and geomorphic mapping, a conceptual time series of hillslope
response to uplift and climate change-induced river incision is derived for a timeframe
encompassing the last glacial-interglacial cycle.
Using the same high resolution topography datasets, in-depth field analysis, and
tephrochronology, the 18,000 year sediment yield from terrestrial deep-seated landslides
in theWSS is estimated in order to investigate the magnitude of hillslope response to
climate-modulated, uplift driven river incision. This completes one of the first processbased
millennial time-scale sediment budgets for this class of temperate maritime, active
margin catchments. Fluvial and geomorphic modelling is applied to reconstruct pre
18,000 cal. yr BP topography in 141 km2 of detailed study area and the resulting
volumetric estimates from 207 landslides are used to estimate deep-seated landslide
sediment flux for the broader system. An estimated 10.2 km3 of deep-seated landslidederived
sediment with a multiplicative uncertainty of 1.9 km3 (+9.2 km3, -4.8 km3) was
delivered to terrestrial and marine sinks. This accounts for between 10 and 74% of the
total mass of the terrestrialWSS budget of ca. 91,000 Mt (+37,000 Mt, -26,000 Mt).
Combining the deep-seated landslide results with other studies of terrestrial sediment
sources and terrestrial and shelf sinks, the estimated terrestrial source load ranges from
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Abstract
1.2 to 3.7 times larger than the mass of sediment sequestered in terrestrial and shelf
depocentres. This implies that off-shelf transport of sediment is important in this system
over the last 18,000 cal. yr BP, as it is today for anthropogenic reasons. Based on the
derived sediment budget, the denudation rate for the terrestrialWSS of 0.8 mm yr-1 (+0.3
mm yr-1, -0.2 mm yr-1) is indistinguishable from the average terrestrialWaipaoa late
Quaternary uplift rate, indicating an approximate steady-state balance between
denudation and uplift. This thesis provides a quantitative analysis of the role of deepseated
landslides in an active margin catchment that is used to improve the
understanding of landscape and terrestrial source-to-marine-sink sediment transfer
dynamics.
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Garófano, Gómez Virginia. "Riparian vegetation patterns according to hydrogeomorphological factors at different spatial and temporal scales in Mediterranean rivers." Doctoral thesis, Universitat Politècnica de València, 2013. http://hdl.handle.net/10251/29395.
Full textAbstract:
Los corredores riparios en ambientes semiáridos mediterráneos son ecosistemas de gran biodiversidad y
complejidad. En ellos confluyen una gran variedad de perturbaciones naturales capaces de crear un mosaico
espacial y temporal con pocos paralelos en otros ecosistemas. Sin embargo, a pesar de su valor, los ecosistemas
riparios están amenazados debido a los altos niveles de intervención humana. La construcción de presas (y la
consecuente manipulación del caudal) está considerada como la perturbación humana más importante que se
cierne sobre ellos. Esta tesis ha tenido como objetivo analizar el ecosistema ripario, abarcando diferentes escalas
espaciales y temporales, y centrándose en los factores que influyen en la distribución, estructura, composición,
calidad y dinámica de su vegetación, tanto en tramos naturales como hidrológicamente alterados de ríos
mediterráneos, concretamente de la Demarcación Hidrográfica del Júcar (Este de España).
Para lograr este objetivo, se han hecho los siguientes aportes a la investigación: A) Determinar los patrones de
distribución de especies leñosas riparias en el gradiente transversal de la ribera y definir grupos de especies con
respuesta similar a las condiciones físicas del hábitat; B) Comparar la respuesta de dichas especies en tramos
naturales y alterados hidrológicamente; C) Definir curvas de respuesta y gremios hidrológicos de especies en
tramos con régimen natural; D) Establecer los principales factores que determinan la calidad del hábitat ripario y
fluvial y los patrones longitudinales de la composición florística, así como de las características del hábitat fluvial
en un segmento hidrológicamente alterado; E) Describir los cambios espacio-temporales en la estructura y
complejidad de la vegetación, y los cambios temporales en el régimen de caudales del corredor ripario de un
tramo hidrológicamente alterado.
Los objetivos anteriores fueron abordados con diferentes metodologías que implicaron la combinación de
diversas fuentes de información y un esfuerzo importante en la toma de datos en varios lugares de estudio de los
ríos Cabriel, Mijares y Serpis. Para cumplir con los objetivos A y B, se llevaron a cabo un muestreo de suelos y
un muestreo georreferenciado de vegetación a través de transectos transversales al cauce en dos tramos naturales
y tres regulados. Los datos fueron analizados con estadística robusta y multivariante. Para cumplir el objetivo C,
el muestreo georreferenciado anterior (junto con un muestreo dendrocronológico) fue acoplado con un modelo
hidráulico en los dos tramos naturales, con el fin de obtener la serie temporal de cotas del agua a la que habían
estado expuestas cada una de las plantas durante su vida. La respuesta de las especies y su posible agregación en
gremios hidrológicos fue comparada mediante estadística robusta en relación a la duración de la inundación,
duración de la inundación durante el período de crecimiento, duración continua de la inundación, frecuencia de
inundación y elevación de la planta respecto al caudal base. Para lograr el objetivo D, toda la sección regulada del
río Serpis (desde la presa Beniarrés - hasta la desembocadura; 40 km) se dividió en segmentos. En cada uno de
ellos se llevó a cabo un inventario de flora y se aplicaron índices hidromorfológicos. Los segmentos fueron
agrupados de acuerdo a su composición florística y características del hábitat fluvial utilizando diferentes técnicas
de estadística multivariante. Finalmente se discutieron los factores principales que controlan los patrones
espaciales de la composición florística, las características del hábitat fluvial, la calidad del hábitat ribereño y la
heterogeneidad del hábitat fluvial. Para alcanzar el objetivo E, se combinaron series históricas de caudales y su
manipulación humana con imágenes aéreas históricas (reveladoras de cambios en la cubierta vegetal) y
observaciones de campo de la distribución de edades de la vegetación y morfología del corredor ripario del río
Mijares en los últimos 60 años. De esta información, se extrajeron métricas del paisaje e índices hidrológicos para
identificar y resumir los cambios espacio-temporales en la estructura de la ribera y en el régimen de caudales.
El estudio a escala transversal nos ayudó a comprender en cada uno de los tramos la zonación de las especies
leñosas riparias en función de la morfología y características del suelo, revelando que la alteración del caudal
puede influir en la modificación de los patrones posicionales de las especies. Se definieron tres gremios
hidrológicos: ¿altamente tolerante a la inundación¿, ¿tolerante intermedio¿ y ¿de transición entre ripario y
terrestre¿. El estudio a escala longitudinal sugirió que la respuesta de la vegetación a un cambio hidrológico es
altamente dependiente de la geomorfología local. Se constató que los factores principales que determinan los
patrones hidromorfológicos y florísticos son un régimen de caudales artificial y altamente variable (identificado
en los segmentos con peor calidad del hábitat ripario y fluvial), la presencia de estructuras laterales en el cauce y
las características geomorfológicas. Como efectos importantes de la regulación del caudal a largo plazo, el estudio
a escala espacio-temporal reveló un aumento en la cobertura y densidad de la vegetación leñosa, una deriva en la
composición de especies y una disminución en las áreas de sedimento desnudo (esencial para el reclutamiento de
las especies riparias pioneras), junto con una reducción sincrónica en la complejidad de la ribera. Estos cambios
estarían relacionados con la disminución de la magnitud y variabilidad de los caudales en las últimas seis décadas.
Solo una mejor comprensión de los procesos ecohidrológicos y de las implicaciones de la alteración hidrológica
sobre los ecosistemas riparios mediterráneos podrá apoyar la integración eficaz de estos sistemas en las
decisiones de gestión del agua.Garófano Gómez, V. (2013). Riparian vegetation patterns according to hydrogeomorphological factors at different spatial and temporal scales in Mediterranean rivers [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/29395
TESIS
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Szeder, Thore. "Active tectonics in the NW German Basin evidence from correlations between the modern landscape and deep geological structures (Lower Saxony, river Hunte) /." [S.l. : s.n.], 2003. http://ArchiMeD.uni-mainz.de/pub/2003/0038/diss.pdf.
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