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Untersuchung und Modellierung von Wasserhaushalt und Stofftransportprozessen in grundwassergeprägten Landschaften am Beispiel der Unteren Havel / Experimental and model based investigations of water balance and nutrient dynamics of groundwater influenced floodplains - the example of the Lower Havel RiverKrause, Stefan January 2005 (has links)
Das
Ziel dieser Arbeit ist die Untersuchung der Wasserhaushaltsprozesse und Stofftransportvorgänge
innerhalb der grundwassergeprägten Talauenlandschaften von Tieflandeinzugsgebieten am Beispiel
der im Nordostdeutschen Tiefland gelegenen Havel. Die Arbeiten in verschieden skaligen
Teileinzugsgebieten der Havel beschäftigen sich dabei zum einen mit der experimentellen Untersuchung
und vorrangig qualitativen Beschreibung der Wasserhaushaltsdynamik, zum anderen
mit der Entwicklung eines zur quantitativen Analyse von Wasserhaushalts- und Stofftransportprozessen
geeigneten Modells und der anschließenden Modellsimulation von Wasserhaushalt
und Stickstoffmetabolik im Grundwasser sowie der Simulation von Landnutzungs- und
Gewässerstrukturszenarien.<br><br>
Für die experimentelle Untersuchung der
Abflussbildung und der Wasserhaushaltsprozesse in den Talauenlandschaften des Haveleinzugsgebiets
wurde Einzugsgebiet der
”Unteren Havel Niederung“ ein umfangreiches Messnetz
installiert. Dabei wurden an mehreren Messstationen und Pegeln meteorologische
Parameter, Bodenfeuchte sowie Grundwasserstände und Abflüsse beobachtet. Die Analyse
der Messergebnisse führte zu einem verbesserten Verständnis von Wasserhaushaltsprozessen
in der durch das oberflächennahe Grundwasser und die Oberflächengewässerdynamik beeinflussten Talauenzone. Darüber hinaus konnten durch die Implementierung der Messergebnisse
konsistente Anfangs- und Randbedingungen für die Wasserhaushalts- und Grundwassermodellierung
im Modellkonzept IWAN realisiert werden.
Mit dem Modell IWAN (Integrated Modelling of Water Balance and Nutrient
Dynamics) wurde ein Werkzeug geschaffen, welches die Berücksichtigung spezifischer
hydrologischer Eigenschaften von Tieflandauen, wie z. B. den Einfluss des oberflächennahen
Grundwassers bzw. der Dynamik von Oberflächenwasserständen auf den Wasserhaushalt, ermöglicht. Es basiert auf der Kopplung des deterministischen distribuierten hydrologischen Modells
WASIM-ETH mit dem dreidimensionalen Finite-Differenzen-basierten Grundwassermodel
MODFLOW. Die Modellierung der Stickstoffmetabolik im Grundwasser erfolgt durch das mit Grundwassermodell
gekoppelte Stofftransportmodel MT3D.
Zur modellbasierten Simulation des Wasserhaushalts der Tieflandauenlandschaften wurde das Modellkonzept IWAN für verschieden skalige Teileinzugsgebiete
an der Havel für Simulationszeiträume von 2 Wochen
bis zu 13 Jahren angewandt. Dabei wurden die Teilmodelle für Wasserhaushalts- und Grundwassermodellierung
in zwei unterschiedlichen Teileinzugsgebieten der
”Unteren Havel Niederung“
kalibriert. Die anschließende Validierung erfolgte für das gesamte Einzugsgebiet der
”Unteren
Havel“. Die Unsicherheiten des Modellansatzes sowie die Anwendbarkeit des Modells im Untersuchungsraum
wurden geprüft und die Limitierung der Übertragbarkeit auf andere grundwasserbeeinflusste
Tieflandeinzugsgebiete analysiert. Die Ergebnisse der Wasserhaushaltssimulationen
führen einerseits zum erweiterten Prozessverständnis des Wasserhaushalts in Flachlandeinzugsgebieten,
andererseits ermöglichten sie durch die Quantifizierung einzelner Prozessgrößen die
Beurteilung der Steuerungsfunktion einzelner Wasserhaushaltsprozesse. Auf der Basis lokaler
Simulationsergebnisse sowie geomorphologischer und gewässermorphologischer Analysen
wurde ein Algorithmus entwickelt, welcher die Abgrenzung des direkten Eigeneinzugsgebiets
der Havel als Raum der direkten Interaktion zwischen Oberflächengewässer und umgebendem
Einzugsgebiet beschreibt. Durch Simulation des Wasserhaushalts im Eigeneinzugsgebiet mit
dem Modell IWAN konnten die Interaktionsprozesse zwischen Fluss und Talauenlandschaft
quantitativ beschrieben werden. Dies ermöglichte eine Bewertung der Abflussanteile aus dem
Eigeneinzugsgebiet sowie eine Quantifizierung der zeitlich variablen Retentionskapazität der
Auenlandschaft während Hochwasserereignissen.
Zur Abschätzung des Einflusses veränderter Landnutzung und angepassten
Managements auf den Wasserhaushalt der Talaue wurden Szenarien entwickelt, welche
Änderungen der Landnutzung sowie der Gewässergeometrie implizieren. Die Simulation
des Wasserhaushalts unter jeweiligen Szenariobedingungen ermöglichte die detaillierte Analyse
sich ändernder Randbedingungen auf den Gebietswasserhaushalt und auf die Austauschprozesse
zwischen Grundwasser und Oberflächengewässer.
Zur Untersuchung der Stickstoffmetabolik
im Grundwasser der Talauenlandschaft wurde das im Modellkonzept IWAN integrierte
Stofftransportmodell MT3D für das Eigeneinzugsgebiet der Havel angewandt. Dies ermöglichte eine Bilanzierung der aus dem Grundwasser des Eigeneinzugsgebiets stammenden
Nitratfrachtanteile der Havel sowie von Nitratkonzentrationen im Grundwasser. Szenariensimulationen, welche verminderte
Nitrateinträge aus der durchwurzelten Bodenzone annehmen, ermöglichten die Quantifizierung der Effizienz von Managementmaßnahmen
und Landnutzungsänderungen in Hinblick auf die Minimierung von Einträgen
in Grundwasser und Oberflächengewässer. / For a sustainable management of lowland river basins, a comprehensive knowledge about floodplain
water balance and nutrient transport processes is required. This investigation aims to
analyse water balance processes and nutrient dynamics and transport within the groundwater
influenced floodplains of lowland areas. Thus, the investigation was focused on the Havel river
catchment at the Northeast German Lowlands, which is a typical example of a lowland
floodplain. Experimental investigations were performed at different spatial scales for qualitative
analysis of water balance. The complex model IWAN was developed which enables the
simulation and quantitative analysis of water balance and nutrient dynamics. Furthermore it allows
the scenario based simulation and analysis of changing landuse management and boundary
conditions.<br><br>
For experimental investigation of runoff generation
and water balance processes within the floodplains of the Havel river an extensive measurement
campaign was installed at several testsites of the 198 km2 catchment of the “Lower Havel river
basin“. These testsites include stations and gauges for the observation of meteorological parameters,
soil moisture, groundwater depths and river runoff. Analysis of the observed data led to
an improved understanding of water balance processes within the specific part of the floodplain
which is influenced by the dynamics of the uppermost groundwater and by the surface water
dynamics. Furthermore the implementation of the observed data within the model concept realised
the consistent definition of time variable, spatial distributed initial and boundary conditions.
The IWAN model was developed as a tool which implements the speci-
fic hydrological characteristics of floodplains within the concept of modelling water balance
and nutrient dynamics. It is based on the coupling of the distributed deterministic hydrological
model WASIM-ETH with the three-dimensional finite difference based numerical groundwater
model MODLFOW. Simulation of the metabolism of nitrogen within the groundwater
passage was realised by the nutrient transport model MT3D which was coupled with the
groundwater model.
For model based simulation of the water balance within lowland
river floodplains the IWAN model was applied for different scaled subcatchments of the Havel
river with varying sizes from 2 to 1000 km2 and simulation periods from 2 weeks up to 13 years.
Calibration of the model was performed for two different sized subcatchments of the “Lower Havel river basin“. The subsequent validation of the model focused on the entire “Lower Havel
river basin“. Uncertainties of the model approach and the limited applicability and transferability
for further groundwater influenced floodplain landscapes were analysed. The results of
the water balance simulations led to an improved understanding of the processes and dynamics
within floodplains. It furthermore enabled the quantification and impact analysis of certain processes
and interactions. Based on local simulation results and on the analysis of surface and
groundwater morphology an algorithm was developed which was used for delineation of the direct
catchment of the Havel river. This direct catchment is specified as the part of the floodplain
which is characterised by the direct interaction between river and adjacent catchment. Water
balance simulations with the IWAN model in the direct catchment led to the quantification of
interaction processes between river and floodplain. This enabled the assessment of the runoff
fraction from the direct catchment during the ecologically sensitive low flow periods in summer
and of the retention capacity of the floodplain during flood events.
For the evaluation of the influences of alternative landuse management
on the water balance within floodplains, complex scenarios were developed which implemented
alterations of landuse or changes of surface water geometries and drainage structures. Simulation
of water balances for each scenario allowed the detailed analysis of changing boundary
conditions on the floodplain water balance and on the interaction processes between groundwater
and river.
Modelling nitrogen metabolism within the groundwater: For investigation of the nitrogen
metabolism within the groundwater of floodplains the nutrient transport and dynamics model
MT3D, which considers also interactions between groundwater and surface waters, was integrated
in the IWAN concept. The model was applied for the simulation of nitrate dynamics within
the direct catchment of the Havel river.With this approach, the nitrate loads between groundwater
and river could be quantified. In addition, nitrate concentrations within the groundwater were
analised in dependence of surface water dynamics. Scenario simulations, assuming a decrease
of incoming nitrate loads from the root zone, caused by landuse techniques, led to the quantification
of the efficiency of landuse changes and advanced management strategies to inhibit
pollution of groundwater and surface waters.
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Geomorphic form and process of sediment flux within an active orogen : denudation of the Bolivian Andes and sediment conveyance across the Beni Foreland /Aalto, Rolf Erhart. January 2002 (has links)
Thesis (Ph. D.)--University of Washington, 2002. / Includes bibliographical references (leaves 240-251).
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Plant associations of the Rillito floodplain in Pima County, ArizonaWillis, Eva Lavina, 1899- January 1939 (has links)
No description available.
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Floodplain management in Quebec : a case study of the Mille Iles River floodplainsHolowaty, Nadja Deyglun. January 1985 (has links)
No description available.
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Optimal prediction of coastal acid sulphate soil severity using geographic information systemsMorgan, Marcus John. January 2006 (has links)
Thesis (M.Eng.)--University of Wollongong, 2006. / Typescript. Includes bibliographical references: leaf 174-183.
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Primary succession of lianas in an Amazonian floodplain forest /McManus, Erin Michael. January 2003 (has links)
Thesis (M.S.)--Wake Forest University. Dept. of Biology, 2003. / Includes bibliographical references (leaves 44-47).
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The influence of hydrology and time on productivity and soil development of created and restored wetlandsAnderson, Christopher John, January 2005 (has links)
Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Includes bibliographical references (p. 153-166).
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OXYGEN AND HYDROGEN STABLE ISOTOPE RATIOS IN MISSISSIPPI RIVER FLOODPLAIN INVERTEBRATES: IMPLICATIONS FOR DISPERSAL AND FOOD WEB ANALYSISMyers, David John 01 December 2010 (has links)
Understanding energy fluxes within and between floodplain water bodies, and between rivers and their floodplains is essential for comprehending the dynamics of modern, altered river systems. Floodplain aquatic invertebrates may move between habitats deliberately (through emergence and dispersal) or through passive transport during flooding. This movement may represent a significant flux of energy and an essential food web subsidy. I assessed the usefulness of the stable isotopes of hydrogen and oxygen (D and 18O respectively) for identifying the origins and movements of macroinvertebrates in Mississippi River floodplain water bodies. I sampled water and invertebrates from the Mississippi River, intermittent and permanent floodplain wetlands, and tributaries during 2007 and 2008. Results showed consistent relationships between δD and δ18O signatures in invertebrate tissues and their home water bodies. I also investigated whether δD and δ18O could be used as a multivariate "fingerprint" to trace a captured invertebrate back to its environment of origin. Results showed that δD can be a useful tracer of the movement of floodplain invertebrates in some cases, although δ18O is likely not suitable for that purpose.
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Estrutura da comunidade fitoplanctônica, em cinco lagos marginais do Rio Turiaçu, (Maranhão, Brasil) e sua relação com o pulso de inundação.Nogueira, Naiza Maria Castro 30 June 2003 (has links)
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Previous issue date: 2003-06-30 / Financiadora de Estudos e Projetos / The phytoplankton communities of five lakes in the floodplain of Turiaçu River (MA) were
analysed for taxonomic composition and evaluated regarding temporal dynamics. Changes on
phytoplankton densities were analysed as well as the variations in physical and chemical water
characteristics along a hydrological cycle, attempting to correlate them to the flood pulse and the
consequent water level fluctuations. Samplings were carried out in lakes Cabeludo, Caboclo,
Arrodiador, Bate Terra and Quebra Pote, five periods of representative phases: dry, water rising,
flooding, water lowing and a second dry. Qualitative samples were taken by horizontal hauls with a
20 µm phytoplankton net, and quantitative samples were taken at the surface and at 20 cm above
the bottom with a Van Dorn bottle. Samples were preserved with in 4% formalin and the
phytoplankton was identified and enumerated in settling chambers under a Zeiss inverted
microscope. Turbulence, rainfall and water level fluctuations were considered the main controlling
factors of the successional dynamics. The lakes are shallow and nutrient rich, being eutrophic
during the dry period and mesotrophic in the other hydrological phases. The phytoplankton
communities of the five lakes are represented by 139 taxa belonging to 9 Classes: 22
Bacillariophyceae, 34 Chlorophyceae, 1 Cryptophyceae, 33 Cyanophyceae, 2 Dinophyceae, 20
Euglenophyceae, 1 Xanthophyceae and 25 Zignematophyceae. Most taxa are new records for
Maranhão State. Cyanophyceae was the numerically dominant group in three periods: water rising
(March), water lowing (August) and dry (December), with relative abundances varying from
23.13% in Lake Caboclo during the water raising period to 65.72% of the total, at the same lake, in
the dry period. Bacillariophyceae were the most abundant organisms in the flooding period (May),
with relative abundances varying from 38,14 % in Lake Bate-Terra to 49,70% in Lake Caboclo.
The most abundant species of Cyanophyceae and Bacillariophyceae were Planktolyngbya
circumcreta and Aulacoseira granulata, respectively. Total phytoplankton densities varied from
1725 ind.mL-1 in Lake Arrodiador, in the flood period, to 8272 ind.mL-1 in Lake Cabeludo, at the
dry period. The highest densities occurred in dry periods, related to the greater nutrient availability
and to the concentration factor resulting from the water level decrease. There was a tendency to
higher species richness, lower dominance, higher equitativity and higher diversity of phytoplankton
during water rising and water lowering. / As comunidades fitoplanctônicas de cinco lagos da planície de inundação do rio Turiaçu (MA)
foram analisadas para a composição taxonômica e avaliadas de acordo com sua dinâmica temporal.
As variações na densidade do fitoplâncton também foram avaliadas, assim como as mudanças nas
características físicas e químicas da água dos lagos, ao longo de um ciclo hidrológico, buscando
correlacioná-las com o pulso de inundação e as conseqüentes variações no nível de água dos lagos.
As amostragens foram realizadas nos lagos Cabeludo, Caboclo, Arrodiador, Bate Terra e Quebra
Pote, em cinco épocas representativas dos períodos: de seca, enchente, cheia, vazante e de um
segundo período de seca, tendo sido realizadas coletas qualitativas, por meio de arrastos
horizontais, com rede de 20 µm de abertura de malha e coletas quantitativas do fitoplâncton total,
na superfície e 20 cm acima do fundo, com Garrafa de Van Dorn. As amostras foram preservadas
em formalina 4% e quantificadas em câmaras de sedimentação, sob microscópio invertido Zeiss. A
turbulência, a precipitação e as variações no nível d água foram consideradas os principais fatores
controladores da dinâmica sucessional. Os lagos são rasos e suas águas ricas em nutrientes, sendo
os lagos eutróficos nos períodos de seca e mesotróficos nos outros períodos hidrológicos. As
comunidades fitoplanctônicas dos cinco lagos estão representadas por 139 táxons, distribuídos em
9 Classes: 22 Bacillariophyceae, 34 Chlorophyceae, 1 Cryptophyceae, 33 Cyanophyceae, 2
Dinophyceae, 20 Euglenophyceae, 1 Xanthophyceae e 25 Zignematophyceae. A maioria dos táxons
são novas ocorrências para o estado do Maranhão. Cyanophyceae foi a classe numericamente mais
abundante em três períodos: enchente (março), vazante (agosto) e seca (dezembro), com
abundâncias relativas que variaram de 23,13% no lago Caboclo no período de enchente, a 65,72%
do total, neste mesmo lago, no período de seca. Bacillariophyceae foi a classe mais abundante no
período de cheia (maio), com abundância relativa variando de 38,14 % no lago Bate-Terra a
49,70% no lago Caboclo. As espécies mais abundantes das classes Cyanophyceae e
Bacillariophyceae foram Planktolyngbya circumcreta e Aulacoseira granulata, respectivamente.
As densidades totais do fitoplâncton variaram de 1.725 ind.mL-1 no lago Arrodiador, no período de
cheia, a 8.272 ind.mL-1 no lago Cabeludo, no período de seca. As maiores densidades ocorreram
nos períodos de seca, relacionadas à maior disponibilidade de nutrientes e ao fator de concentração,
pela redução no nível de água. As comunidades tenderam a uma maior riqueza de espécies, menor
dominância, maior uniformidade e maior diversidade nas fases de enchente e vazante.
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Limnologia de lagos de várzea do rio Madeira com ênfase na diversidade e produção secundária da comunidade zooplanctônicaNegreiros, Natalia Felix 06 March 2014 (has links)
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Previous issue date: 2014-03-06 / Financiadora de Estudos e Projetos / The study of diversity and productivity can contribute to understanding the functioning of Amazonian ecosystems as a whole and especially to the conservation of its aquatic biota, considered one of the richest in species on the planet. The present study aimed to analyze the course of three years the limnological characteristics of three floodplain lakes of the Madeira River in the area of influence of the Santo Antônio hydroelectric plant on the Madeira, in the region near to Porto Velho, Rondônia, with emphasis on the zooplankton community. Samples were quarterly covering the four major hydrological periods: low water, flood, high water and ebb over three years (2010-2013). Physical, chemical and biological variables of the lakes were collected and correlated with species composition, biomass and production of zooplankton. The zooplankton community was characterized by high species richness (195 taxa) and high degree of endemism for the group of Copepoda Calanoida. The results showed that the three lakes have eutrophic or mesotrophic characteristics. The highest values of density and biomass of zooplankton in the lake occurred Cujubim. The rotifers were numerically dominant, but the Copepoda dominated in biomass and secondary production in lakes Cuniã and San Miguel. There was little variability in secondary production of zooplankton, being slightly higher in the lake Cujubim with increased production of copepods and rotifers in this lake. The rainfall variation demarcated the occurrence of well-defined hydrological periods, directly affecting the hydrodynamics of this region, controlling population fluctuations of zooplankton, probably brought by the increased availability of resources on the Madeira River in the flood season, playing an important role in the organization of food webs, and how to link the transfer of matter and energy in food chains. / O estudo da diversidade e produtividade pode contribuir para o entendimento do funcionamento dos ecossistemas amazônicos como um todo e principalmente para a conservação da sua biota aquática, considerada uma das mais ricas em espécies no planeta. O presente estudo teve como objetivo analisar ao longo de três anos as características limnológicas de três lagos de várzea do rio Madeira na área de influência da Usina Hidroelétrica Santo Antônio do Madeira, na região próxima a Porto Velho, Rondônia, com ênfase na comunidade zooplanctônica. As amostragens foram trimestrais abrangendo os quatro períodos hidrológicos principais: Águas baixas, enchente, águas altas e vazante, ao longo de três anos (2010-2013). Foram coletadas variáveis físicas, químicas e biológicas dos lagos, correlacionando com a composição de espécies, além de determinadas a biomassa e a produção da comunidade zooplanctônica. A comunidade zooplanctônica foi caracterizada por elevada riqueza de espécies (195 táxons) e alto grau de endemismo para o grupo dos Copepoda Calanoida. Os resultados obtidos evidenciaram que os três lagos apresentam características mesotróficas ou eutróficas. Os maiores valores de densidade e biomassa da comunidade zooplanctônica ocorreram no lago Cujubim. Os Rotifera foram numericamente dominantes, mas os Copepoda dominaram em biomassa e produção secundária, nos lagos Cuniã e São Miguel. Houve pequena variabilidade na produção secundária da comunidade zooplanctônica, sendo ligeiramente superior no lago Cujubim, com maior a produção de Copepoda e Rotifera neste lago. A variação pluviométrica demarcou a ocorrência de períodos hidrológicos bem definidos, afetando diretamente a hidrodinâmica desta região, controlando flutuações populacionais da comunidade zooplanctônica, provavelmente pela maior disponibilidade de recursos trazidos do rio Madeira nos períodos de cheia, desempenhando papel importante na organização das teias tróficas, e como elo de transferência de matéria e energia nas cadeias alimentares.
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