Charwell Basin is a 6 km-wide structural depression situated at the boundary between the axial ranges and faulted and folded Marlborough Fault Zone of north-eastern South Island, New Zealand. The basin contains the piedmont reach of the Charwell River, and a series of late Quaternary loess-mantled alluvial terraces and terrace remnants that have been uplifted and translocated from their sediment source due to strike-slip motion along the Hope Fault which bounds the basin to its immediate north. The aim of this study was to provide an interdisciplinary, integrated and holistic analysis of late Quaternary landscape evolution and environmental change in Charwell Basin using terrain analysis, loess stratigraphy, soil chemistry and paleoecological data. The study contributes new understanding of New Zealand landscape and ecosystem responses to regional and global climatic change extending to Marine Isotope Stage (MIS) 6, and shows that climatically-forced shifts in biogeomorphic processes play a significant role in lowland landscape evolution. Morphometric analysis of alluvial terraces and terrace remnants of increasing age demonstrated geomorphic evolution through time, with a decrease in extent of original planar terrace tread morphology and an increase in frequency of steeper slopes and convexo-concave land elements. Paleotopographic analysis of a >150 ka terrace mantled by up to three loess sheets revealed multiple episodes of alluvial aggradation and degradation and, subsequent to river abandonment, gully incision prior to and coeval with loess accumulation. Spatial heterogeneity in loess sheet preservation showed a complex history of loess accumulation and erosion. A critical profile curvature range of -0.005 to -0.014 (d²z/dx², m⁻¹) for loess erosion derived from a model parameterised in different ways successfully predicted loess occurrence on adjacent slope elements, but incorrectly predicted loess occurrence on an older terrace remnant from which all loess has been eroded. Future analyses incorporating planform curvature, regolith erosivity and other landform parameters may improve identification of thresholds controlling loess occurrence in Charwell Basin and in other South Island landscapes. A loess chronostratigraphic framework was developed for, and pedogenic phases identified in, the three loess sheets mantling the >150 ka terrace. Except for one age, infrared-stimulated luminescence dates from both an upbuilding interfluve loess exposure and colluvial gully infill underestimated loess age with respect to the widespread Kawakawa/Oruanui Tephra (KOT; 27,097 ± 957 cal. yr BP), highlighting the need for improvements in the methodology. Onset of loess sheet 1 accumulation started at ca. 50 ka, with a break at ca. 27 ka corresponding to the extended Last Glacial Maximum (eLGM) interstadial identified elsewhere in New Zealand. Loess accumulation through MIS 3 indicates a regional loess flux, and that glaciation was not a necessary condition for loess generation in South Island. Loess accumulation and local alluvial aggradation are decoupled: the youngest aggradation event only covers ~12 kyr of the period of loess sheet 1 accumulation. Older local aggradation episodes could not be the source because their associated terraces are mantled by loess sheet 1. In the absence of numerical ages, the timing of L2 and L3 accumulation is inferred on the basis of an offshore clastic sediment record. The upbuilding phase of loess sheet 2 occurred in late MIS 5a/MIS 4, and loess sheet 3 accumulated in two phases in MIS 5b and late MIS 6. Biogenic silica data were used to reconstruct broad shifts in vegetation and changes in gully soil saturation status. During interglacial/interstadial periods (MIS 1, early MIS 3, MIS 5) Nothofagus-dominated forest covered the area in association with Microlaena spp grasses. Lowering of treeline altitude during glacial/stadial periods (MIS 2, MIS 3, MIS 5b, late MIS 6) led to reduction in forest cover and a mosaic of shrubs and Chionochloa spp, Festuca spp and Poa spp tussock grasses. Comparison of interfluve and gully records showed spatial heterogeneity in vegetation cover possibly related to environmental gradients of exposure or soil moisture. A post-KOT peak in gully tree phytoliths corresponds to the eLGM interstadial, and a shift to grass-dominated vegetation occurred during the LGM sensu stricto. Diatoms indicated the site became considerably wetter from ca. 36 ka, with peak wetness at ca. 30, 25 and 21 ka, possibly due to reduced evapotranspiration and/or increased precipitation from a combination of strengthened westerly winds and increased cloudiness, or strengthened southerly flow and increased precipitation. Human influence after ca. 750 yr BP led to re-establishment of grassland in the area, which deposited phytoliths mixed to 30 cm depth in the soil. A coupled gully colluvial infilling/vegetation record showed that sediment flux during the late Pleistocene was ~0.0019 m³ m⁻¹ yr⁻¹ under a shrubland/grassland mosaic, and Holocene sediment flux was ~0.0034 m³ m⁻¹ yr⁻¹ under forest. This increase of 60% through the last glacial-interglacial transition resulted from increased bioturbation and down-slope soil transport via root growth and treethrow, which formed a biomantle as evidenced by slope redistribution of the KOT. These results contrast with sediment transport rates and processes hypothesised to occur contemporaneously in adjacent mountain catchments. This suggests that intraregional biogeomorphic processes can differ significantly depending on topography and geological substrate, with different landscapes responding in unique ways to the same climate shifts. Analysis of Quaternary terrestrial landscape evolution in non-glaciated mountainous and lowland areas must therefore consider spatial and temporal heterogeneity in sediment fluxes and underlying transport processes.

[pt] A superfície da terra é formada por processos geológicos que geram as rochas, assim como por processos naturais de degradação e de erosão. A erosão destrói as estruturas que compõem o solo e seu transporte é feito pela ação da água da chuva, do vento, da gravidade e até do gelo. A origem e evolução das bacias sedimentares, dentre outros fenômenos, é estudada pela geologia sedimentar, a qual trata do estudo dos processos físicos, químicos e biológicos atuantes na superfície da terra desde o seu início até os dias atuais. Na atualidade, o uso de modelos que permitem analisar processos de escoamento superficial, desprendimento de partículas e de transporte e deposição de sedimentos em bacias hidrográficas é cada vez mais frequente. O uso e análise desses modelos demonstra que, para escalas relativamente pequenas e áreas não muito extensas, o rebaixamento do perfil dos rios está diretamente ligado aos processos de deformação tectônica. Por outro lado, modelos de previsão de evolução do relevo associados com intemperismo, erosão e deposição de sedimentos, considerando escalas espaciais do tipo regional ou continental e escalas de tempo relativamente grandes (maior que 10(5) anos) devem ser desenvolvidos acoplando tanto efeitos tectônicos como morfológicos. Neste trabalho é apresentado um modelo computacional que permite analisar a evolução na mudança do relevo de bacias hidrográficas, em pequena e grande escala, assim como estimar a produção de sedimento resultante do processo erosivo. O algoritmo de análise é escrito na linguagem de programação Cmais mais e considera a simulação de diferentes cenários, que incluem deformação tectônica, processos de encosta (difusão e movimentos de massa) e processos de incisão fluvial, dando-se particular atenção à formação e evolução da rede fluvial de drenagem. Para a análise de resultados, o programa oferece a visualização 3D de diferentes superfícies: distribuição dos sedimentos, evolução da rede fluvial, mudanças topográficas do relevo, etc. / [en] The surface of the earth is formed by geological processes that originate the rocks, as well as for natural processes of degradation and erosion. The erosion destroys the soil structures and the transport of sediments is made by the action of the rain water, wind, gravity and, in some cases, ice. The origin and evolution of sedimentary basins, amongst other phenomena, are studied by the sedimentary geology, which deals with the analysis of physical, chemical and biological processes that act directly on earth surface since its origin until the current days. Nowadays, the use of runoff - erosion models that analyze processes such as detachment of particles and transport and deposition of sediment in drainage basins is every time more frequent. The use of these models demonstrates that, for relatively small scales and not very extensive areas, relief changes are directly related to tectonic processes. On the other hand, landscape evolution models and associated weathering, erosion and deposition with parameterization for regional or continental spatial scales and large time scales (more than 10(5) years), must be developed to adequately couple tectonics and geomorphology. Is presented in this work a computational model to analyze the landscape evolution in hydrographic basins, considering small and large scales, as well as evaluate the production of sediment resultant of the erosive process. The algorithm is written in the programming language C++ and considers the simulation of different scenes, that include tectonics, hillslope processes (diffusion and landslides) and bedrock incision, giving particular attention to the channel network evolution. For the analysis process the program offers the visualization of different 3D surfaces: sediment distribution, drainage network, topographical relieves etc.

Made available in DSpace on 2015-02-24T19:48:44Z (GMT). No. of bitstreams: 1 SilvanaPPG_TESE_pag119_final.pdf: 4384081 bytes, checksum: f4e3889e03bd2b77ef4e8f1b271723a8 (MD5) Previous issue date: 2012-08-06 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The Northeast relief was described by the Pediplanation Model. This action discards the theoretical basis of post-Cretaceous tectonic evolution of the landscape. Through this model the Massif Pereiro - MP, Borborema Province, was established as part of the Tablelands Area Residual Sertanejos. The present work aims to establish the post- Cretaceous morphotectonic evolution of the MP by geomorphological and geological mapping using Geographic Information System, Remote Sensing and dating of sediments by Single Aliquot Regenerative-dose (SAR). The MP is contained in the core semi-arid, annual precipitation of 600-800 mm / year. The MP is NE-SW, is limited by Shear Zone Jaguaribe (ZCJ) and Portalegre Shear Zone (ZCPa), the same attitude, and crossed by several other shear zones. These shear zones show evidence of brittle Cenozoic reactivation, mostly as normal faults and shallow crustal level. The Quaternary sedimentation around the MP focuses on fault escarpments in a general pattern cascade, where ages decrease from the summits of the steep foothills. The ages of 51 sediment samples indicate a correlation with global climate following pulses: Last Interestadial-UI, the Last Glacial Maximum - LGM and the transition Pleistocene / Holocene, while the latter focus on 18 of 51 samples dated. This study also finds evidence of a new quaternary basin, here called Merejo Basin. Through these results it is concluded that no evidence of post-Cretaceous tectonic evolution of morphological MP, as their retreat along the fault scarps, invariably following the trend of the shear zones. The erosion of cliffs in large time scale is controlled by weakness zones generated by faults on the other hand the erosion of cliffs in short time, with the formation of deposits and colluvial horizons pedogenizados, has climate control. It was also found that in the study area there is a preponderance of past and current tectonic erosion processes on the morphological evolution / O relevo do Nordeste foi descrito por meio do modelo de pediplana??o. Esta base te?rica descarta a atua??o da tect?nica p?s-cret?cea na evolu??o da paisagem. Atrav?s deste modelo o Maci?o do Pereiro MP, Prov?ncia Borborema, foi definido como parte do Dom?nio dos Planaltos Residuais Sertanejos. O presente trabalho tem por objetivo estabelecer a evolu??o morfotect?nica p?s-cret?cea do MP, atrav?s da cartografia geol?gica e geomorfol?gica com uso de Sistema de Informa??o Geogr?fica, Sensoriamento Remoto e data??o de sedimentos por Single Aliquot Regenerative-dose (SAR). O MP est? contido no n?cleo semi?rido, de precipita??o anual entre 600 a 800 mm/ano. O MP tem dire??o NE-SW, ? limitado pela Zona de Cisalhamento de Jaguaribe (ZCJ) e Zona de Cisalhamento Portalegre (ZCPa), de mesma atitude, e atravessado por v?rias outras zonas de cisalhamento. Estas zonas de cisalhamento apresentam evid?ncias de reativa??o fr?gil cenozoica, na sua maioria como falhas normais e de n?vel crustal raso. A sedimenta??o quatern?ria em torno do MP se concentra em escarpas de falhas, em um padr?o geral em cascata, onde as idades diminuem das cimeiras aos sop?s das escarpas. As idades de 51 amostras de sedimentos indicam correla??o com seguintes pulsos clim?ticos globais: ?ltimo Interestadial- UI, o ?ltimo M?ximo Glacial - UMG e a transi??o Pleistoceno/Holoceno, sendo que nesta ?ltima concentram-se 18 das 51 amostras datadas. O presente trabalho tamb?m encontra evid?ncias de uma nova bacia quatern?ria, aqui denominada de Bacia Merejo. Atrav?s destes resultados conclui-se que h? evidencia de tect?nica p?s-cret?cea na evolu??o morfol?gica do MP, pois as suas escarpas recuam paralelamente ?s falhas, seguindo invariavelmente o trend das zonas de cisalhamento. A eros?o das escarpas em grande escala de tempo ? controlada pelas zonas de fraqueza geradas pelos falhamentos, por outro lado ? eros?o das escarpas em curtos espa?os de tempos, com a forma??o dos dep?sitos coluvionares e horizontes pedogenizados, possui controle clim?tico. Concluise ainda que na ?rea de estudo haja a preponder?ncia da tect?nica pret?rita e atual sobre os processos erosivos na evolu??o morfol?gica

<p>Understanding climate-driven changes in global land-based ice volume is a critical component in our capability to predict how global sea level will rise as a consequence of the current human-driven climate change. At the last glacial maximum (LGM, which peaked around 20 ka), ephemeral ice sheets covered vast regions of the northern hemisphere while both the Greenland and Antarctic ice sheets were more extensive than at present. As global temperatures rose at the transition into the Holocene, driving the LGM deglaciation, eustatic sea level rose by approximately 125 m. The east Antarctic ice sheet (EAIS) is the largest ice sheet on Earth today, holding an ice volume equivalent to ca. 53 m rise in global sea level. Considering current trends in global climate, specifically rapidly increasing atmospheric CO₂ levels and global temperature, it is important to improve our understanding of how the EAIS will respond to global warming so that we can make better predictions of future sea level changes to guide community adaptation and planning efforts. Numerical ice sheet models which inform projections of future ice volume changes, and can, therefore, yield projections of sea level rise, rely on empirical data to test their ability to accurately represent former and present ice configurations. However, there is a general lack of data on the paleoglaciology of the EAIS along the western Dronning Maud Land (DML) margin. In order to address this situation, the paleoglaciology of western DML forms the focus of the work presented in this thesis.</p><p><b> </b></p><p>Together with collaborators within the MAGIC-DML consortium (Mapping, Measuring and Modelling Antarctic Geomorphology and Ice Change in Dronning Maud Land) that provides the funding for this MS project, the author has performed geomorphological mapping across western DML; an area of approximately 200,000 km². The results of the mapping presented in this thesis will provide the basis for a detailed glacial reconstruction of the region. The geomorphological mapping was completed almost entirely by remote sensing using very high-resolution (sub-meter in the panchromatic) WordView-2 and WorldView-3 (WV) satellite imagery, combined with ground validation studies during field work. Compared to Landsat products, the improved spatial resolution provided by WV imagery has fundamentally changed the scale and detail at which remote sensing based geomorphological mapping can be completed. The mapping presented here is focused on the glacial geomorphology of mountain summits and flanks that protrude through the ice sheet’s surface (nunataks). In our study area of western DML these nunatak surfaces make up <0.2 % of the total surface area, and the landforms mapped here are generally smaller than can be identified from Landsat products (30 m spatial resolution). The detail achieved in our mapping, across such a vast, remote area that presents numerous obstacles to accessibility highlights the benefits of utilizing the new VHR WV data. As such an evaluation of the WV data, as applied to geomorphological mapping is presented here together with our mapping of the glacial geomorphology of western DML. The results of which provides evidence of ice having overridden sites at all elevations across the entire study area; from the highest elevation inland nunataks that form the coast-parallel escarpment, to low-elevation emerging nunataks close to the coast. Hence from our studies of the glacial geomorphology of this region we can ascertain that, at some point in the glacial history of western DML, ice covered all of the mountain summits that are exposed today, indicating an ice sheet surface lowering of up to 700 m in some places.</p>

The Western Mediterranean realm is considered as a region highly sensitive with regard to climate changes and landscape transformations. Within its semi arid and semi humid areas, even slight climatic changes but also human interventions may result in far-reaching consequences in respect of environment and ecological systems. Thus, research on landscape development has a high relevance in geosciences, especially in the light of current climate change research. It is a major concern to reveal regularities and patterns in past landscape evolution in order to provide a basis for the assessment of future developments. For the reconstruction of late Quaternary environmental conditions fluvial sediments play an important role as they almost uniquely reflect landscapes and landscape changes on a regional scale. This is due to the fact that fluvial dynamics and all enclosed processes are based on multi-causal relationships and a variety of factors like climatic conditions, vegetation development, human impact, or tectonic activity finds expression in fluvial dynamics. About 70 % of the Iberian Peninsula is influenced by moist Atlantic air masses, but in the whole area there is a considerable research gap concerning the exploration of fluvial archives. Taking this into account, this dissertation aims to systematically work out fluvial sediment successions of two river systems, namely the Jarama River in central Spain and the Guadalete River in southwestern Spain. For complementary considerations, first stratigraphic results from the middle to lower Guadalquivir River in southern Spain will be consulted. In a first step, the objective is to intensively study and document sediment profiles for the purpose of deriving a valuable composite profile for each river system. In a second step, the significance of these composite profiles regarding palaeoenvironmental conditions as well as changes will be examined. Beside the reaction of fluvial systems towards climatic changes, relationships with other influencing factors are a main issue. On the basis of a supra-regional comparison a possible coupling of fluvial geomorphic systems and large-scale climate fluctuations shall be analyzed. Furthermore, it is intended to address issues like system connectivity or varying response times and response durations. The bases for these considerations are abundant sedimentary profile records supported by electrical resistivity tomography and percussion drillings. Stratigraphic work includes the differentiation of sediment units, the identification of soil horizons, and the correlation of specific layers and horizons across different profile sections based on sedimentologic and pedogenetic characteristics. Subsequent soil-chemical and sedimentological laboratory analyses on certain key-profiles imply grain-size analyses, the measurement of organic carbon content, calcium carbonate content, pedogenic and total iron contents, as well as magnetic susceptibility. Laboratory analyses are used to strengthen results of field work and to differentiate between soils and soil sediments in ambiguous cases. The chronological resolution of the sediment successions will be provided by radiocarbon dating. The final aim is to work out a detailed fluvial sedimentation history for the late Quaternary. The precise characterization of the catchment areas, together with a comparison of the stratigraphic findings and secondary archive information from the literature, will enable the identification of relationships between fluvial dynamics and different influencing factors. In this dissertation, 36 profile sections have been worked out intensively. Furthermore, 13 percussion drillings were conducted in floodplain positions with insufficient exposure conditions. For the chronological frame 70 radiocarbon samples have been dated. The obtained results show a significant pattern of sedimentation periods and phases of stability associated with soil formation for each river system. The sedimentation history of the Guadalete and Guadalquivir Rivers could be reconstructed for the last 15 ka, while conclusions with regard to sedimentation dynamics of the Jarama River could be drawn for a period of 43 ka. Thanks to an abundance of available studies on other terrestrial archives with climatic or environmental relevance, it was possible to assess the influence of different parameters such as climate, vegetation, humankind, tectonics, and base-level changes on fluvial sedimentation dynamics. It emerged that, first and foremost, rapid climate changes had significant impact on the mobilization of sediments in the catchment area as well as their deposition in floodplain positions. On the other hand prolonged periods of climatic amelioration caused floodplain stability along with soil formation, as documented for the time spans between 13.3 and 12.7 ka, 7 and 5.1 ka, 2.8 and 2.3 ka, 1.4 and 1.2 ka, as well as 0.8 and 0.5 ka cal. BP in several river systems. Periods of increased sedimentation were initiated by phases of climatic aridification that affected fluvial systems through the weakening of the vegetation cover and the accentuation of the hydrological discharge regime. Corresponding patterns have been found for the time intervals between 8 and 7 ka, 5 and 3.8 ka, 2.2 and 1.5 ka, as well as around 1 ka and 0.4 ka cal. BP. The supra-regional effectiveness of the factor climate is contrasted by a strong regional individuality of the river catchments that is expressed by further, regionally limited phases of fluvial activity. Crucial to this development – apart from regional climate differences – are, inter alia, tectonic movements as evidenced for the Jarama River system in central Spain, or late Pleistocene and Holocene sea-level fluctuations that primarily affected fluvial dynamics along the lower course of the Guadalete River in southwestern Spain. Furthermore, it can be shown that variations in time and duration of fluvial system response are attributable to differing buffer capacities of river catchments towards external influences. The increase of human impact during the late Holocene apparently provoked a reinforcement of the effects of climatic impulses. There are clear evidences for the participation of humans in the mobilization of sediments; however, concerning the degree of influence it is hardly possible to differentiate between the factors humans and climate. / Der westliche Mediterranraum gilt als landschaftlich und klimatisch hochsensible Region, für deren semiaride bis semihumide Gebiete bereits kleinere klimatische Änderungen, aber auch Eingriffe des Menschen, mit weitreichenden Folgen für Umwelt und ökologische Systeme verbunden sein können. Forschungen zum Landschaftswandel nehmen hier vor allem vor dem Hintergrund des derzeitigen Klimawandels einen hohen Stellenwert in den Geowissenschaften ein. Ein wichtiges Anliegen ist dabei, in früheren Landschaftswandeln Muster zu entdecken, welche als Grundlage für Bewertungen zukünftiger Veränderungen dienen können. Für die Rekonstruktion spätquartärer Umweltbedingungen kommt fluvialen Sedimenten eine besondere Rolle zu. Wie kein anderes Archiv spiegeln fluviale Sedimentabfolgen Landschaftszustände und -entwicklung auf regionaler Ebene wieder. Dies ist dem Umstand geschuldet, dass fluviale Dynamik mit allen inbegriffenen Prozessen auf polykausalen Zusammenhängen beruht und somit eine Vielzahl an Faktoren, wie klimatische Verhältnisse und Vegetationsentwicklung, menschliche Einflussnahme oder tektonische Aktivität Ausdruck in fluvialer Dynamik finden. Von feuchten atlantischen Luftmassen geprägte Gebiete nehmen etwa 70 % der Fläche der Iberischen Halbinsel ein, allerdings besteht hier eine erhebliche Forschungslücke im Bereich der Analyse fluvialer Archive. Diesem Umstand soll in vorliegender Dissertation in Form einer systematischen Aufarbeitung der fluvialen Sedimentabfolgen zweier Flusssysteme in Zentralspanien (Rio Jarama), sowie in SW-Spanien (Rio Guadalete) Rechnung getragen werden. Für ergänzende Betrachtungen werden dabei erste Befunde zur stratigraphischen Gliederung des Guadalquivir-Mittellaufes in S-Spanien herangezogen. Ziel der Arbeiten ist es zunächst über umfangreiche Aufnahmen und Dokumentationen von Sedimentprofilen ein belastbares Standardprofil für jedes Flusssystem zu erarbeiten und dieses hinsichtlich der Aussagekraft in Bezug auf Paläoumweltbedingungen und vor allem -wandeln zu prüfen. Neben der möglichen Reaktion fluvialer Systeme auf klimatische Änderungen, stehen dabei vor allem auch Beziehungsgeflechte zu anderen Einflussfaktoren im Vordergrund. Anhand eines überregionalen Vergleichs soll eine mögliche Kopplung fluvialmorphologischer Systeme an großräumige Klimafluktuationen untersucht werden, zudem soll weiteren Themenkomplexen, wie der Konnektivität verschiedener Systeme oder unterschiedlichen Reaktionszeiten und -geschwindigkeiten nachgegangen werden. Grundlage für diese Betrachtungen bilden dabei aus zahlreichen Geländeaufnahmen resultierende Profilaufnahmen, sowie Ergebnisse geoelektrischer Messungen und Bohrsondierungen. Stratigraphische Arbeiten belaufen sich zunächst auf die Untergliederung verschiedener Sedimenteinheiten, die Ausweisung von Bodenhorizonten, sowie die Korrelation einzelner Schichten und Horizonte über unterschiedliche Profile hinweg anhand charakteristischer sedimentologischer und pedogenetischer Merkmale. Nachfolgende bodenchemische und sedimentologische Laboruntersuchungen an ausgewählten Profilen sollen über die Bestimmung von Korngrößenverhältnissen, Gehalten an organischem Kohlenstoff, Kalk- und Eisengehalten, sowie der magnetischen Suszeptibilität die Geländebefunde stützen und in unklaren Fällen eine Unterscheidung von Böden und Bodensedimenten erleichtern. Die zeitliche Auflösung der Sedimentabfolgen soll über Radiokarbondatierungen realisiert werden, mit dem letztendlichen Ziel, eine detaillierte fluviale Sedimentationsgeschichte für das Spätquartär zu erarbeiten. In einem weiteren Schritt werden begleitend zu einer detaillierten Einzugsgebietscharakteristik die chronostratigraphischen Befunde einem intensiven Vergleich mit in der Literatur verfügbaren Studien an Sekundärarchiven zugeführt, um Beziehungsgeflechte zwischen fluvialer Dynamik und verschiedenen Einflussfaktoren aufzudecken. Im Rahmen dieser Dissertation konnten zunächst 36 Profilaufschlüsse detailliert bearbeitet und zudem 13 Rammkernsondierungen in Flussauenpositionen abgeteuft werden. Für den chronologischen Rahmen wurden 70 Radiokohlenstoffproben datiert. Die Ergebnisse zeigen ein deutliches Muster von Sedimentationsphasen und Zeiten der Stabilität mit einhergehender Bodenbildung für jedes Flusseinzugsgebiet. Dabei konnte die Sedimentationsgeschichte der Flusssysteme Rio Guadalete und Rio Guadalquivir für die letzten 15.000 Jahre und des Rio Jarama für die letzten 43 ka rekonstruiert werden. Dank der Fülle an verfügbaren Studien an terrestrischen Vergleichsarchiven mit klima- und umweltrelevantem Bezug war es möglich, den Einfluss der unterschiedlichen Parameter Klima, Vegetation, Mensch und Tektonik, bzw. Erosionsbasis auf die fluviale Sedimentationsdynamik zu prüfen. So zeigte sich, dass vor allem rasche Klimaänderungen in der Lage waren die Mobilisierung von Sedimenten im Einzugsgebiet und deren Ablagerung in den Flussauen zu initiieren. Dahingegen bewirkten anhaltende klimatische Gunstphasen eine Stabilisierung mit einhergehender Bodenbildung, wie für die Zeiträume zwischen 13.3 und 12.7 ka, 7 und 5.1 ka, 2.8 und 2.3 ka, 1.4 und 1.2 ka, sowie 0.8 und 0.5 ka cal. BP für sämtliche Flusssysteme zu verzeichnen ist. Perioden verstärkter Sedimentation folgten in der Regel Phasen klimatischer Aridifizierung, welche über eine Schwächung der Vegetationsbedeckung und Akzentuierung des hydrologischen Abflussregimes in der Lage waren auf das fluviale System Einfluss zu nehmen. Entsprechende Muster konnten für die Zeiträume zwischen 8 und 7 ka, 5 und 3.8 ka, 2.2 und 1.5 ka, sowie um 1 ka als auch 0.4 ka cal. BP dokumentiert werden. Dem überregional wirksamen Einfluss des Faktors Klima steht jedoch eine starke landschaftsgeschichtliche Individualität der verschiedenen Regionen gegenüber, welche in weiteren, regional begrenzten Phasen fluvialer Aktivität zum Ausdruck kommt. Ausschlaggebend sind hier neben der Ausbildung regionaler Klimaunterschiede unter Anderem tektonische Verstellungen, welche für das in Zentralspanien gelegene System des Rio Jarama belegt werden konnten, oder spätpleistozäne und holozäne Meeresspiegelschwankungen, welche sich vor allem auf die fluviale Dynamik im Unterlauf des in SW-Spanien gelegenen Rio Guadalete auswirkten. Desweiteren können Unterschiede in Reaktionsdauer und -geschwindigkeit fluvialer Systeme mit variierendem Puffervermögen der Flusseinzugsgebiete gegenüber äußeren Einflüssen erklärt werden. Das intensivierte Wirken des Menschen im Spätholozän führte allem Anschein nach zu einer Verstärkung der Wirkung klimatischer Impulse, wobei sich klare Evidenzen für eine Beteiligung des Menschen an der Sedimentmobilisierung erkennen lassen, der Umfang des Einflusses des Menschen aber in der Regel nicht klar von dem des Klimas zu trennen ist.

The Western Mediterranean realm is considered as a region highly sensitive with regard to climate changes and landscape transformations. Within its semi arid and semi humid areas, even slight climatic changes but also human interventions may result in far-reaching consequences in respect of environment and ecological systems. Thus, research on landscape development has a high relevance in geosciences, especially in the light of current climate change research. It is a major concern to reveal regularities and patterns in past landscape evolution in order to provide a basis for the assessment of future developments. For the reconstruction of late Quaternary environmental conditions fluvial sediments play an important role as they almost uniquely reflect landscapes and landscape changes on a regional scale. This is due to the fact that fluvial dynamics and all enclosed processes are based on multi-causal relationships and a variety of factors like climatic conditions, vegetation development, human impact, or tectonic activity finds expression in fluvial dynamics. About 70 % of the Iberian Peninsula is influenced by moist Atlantic air masses, but in the whole area there is a considerable research gap concerning the exploration of fluvial archives. Taking this into account, this dissertation aims to systematically work out fluvial sediment successions of two river systems, namely the Jarama River in central Spain and the Guadalete River in southwestern Spain. For complementary considerations, first stratigraphic results from the middle to lower Guadalquivir River in southern Spain will be consulted. In a first step, the objective is to intensively study and document sediment profiles for the purpose of deriving a valuable composite profile for each river system. In a second step, the significance of these composite profiles regarding palaeoenvironmental conditions as well as changes will be examined. Beside the reaction of fluvial systems towards climatic changes, relationships with other influencing factors are a main issue. On the basis of a supra-regional comparison a possible coupling of fluvial geomorphic systems and large-scale climate fluctuations shall be analyzed. Furthermore, it is intended to address issues like system connectivity or varying response times and response durations. The bases for these considerations are abundant sedimentary profile records supported by electrical resistivity tomography and percussion drillings. Stratigraphic work includes the differentiation of sediment units, the identification of soil horizons, and the correlation of specific layers and horizons across different profile sections based on sedimentologic and pedogenetic characteristics. Subsequent soil-chemical and sedimentological laboratory analyses on certain key-profiles imply grain-size analyses, the measurement of organic carbon content, calcium carbonate content, pedogenic and total iron contents, as well as magnetic susceptibility. Laboratory analyses are used to strengthen results of field work and to differentiate between soils and soil sediments in ambiguous cases. The chronological resolution of the sediment successions will be provided by radiocarbon dating. The final aim is to work out a detailed fluvial sedimentation history for the late Quaternary. The precise characterization of the catchment areas, together with a comparison of the stratigraphic findings and secondary archive information from the literature, will enable the identification of relationships between fluvial dynamics and different influencing factors. In this dissertation, 36 profile sections have been worked out intensively. Furthermore, 13 percussion drillings were conducted in floodplain positions with insufficient exposure conditions. For the chronological frame 70 radiocarbon samples have been dated. The obtained results show a significant pattern of sedimentation periods and phases of stability associated with soil formation for each river system. The sedimentation history of the Guadalete and Guadalquivir Rivers could be reconstructed for the last 15 ka, while conclusions with regard to sedimentation dynamics of the Jarama River could be drawn for a period of 43 ka. Thanks to an abundance of available studies on other terrestrial archives with climatic or environmental relevance, it was possible to assess the influence of different parameters such as climate, vegetation, humankind, tectonics, and base-level changes on fluvial sedimentation dynamics. It emerged that, first and foremost, rapid climate changes had significant impact on the mobilization of sediments in the catchment area as well as their deposition in floodplain positions. On the other hand prolonged periods of climatic amelioration caused floodplain stability along with soil formation, as documented for the time spans between 13.3 and 12.7 ka, 7 and 5.1 ka, 2.8 and 2.3 ka, 1.4 and 1.2 ka, as well as 0.8 and 0.5 ka cal. BP in several river systems. Periods of increased sedimentation were initiated by phases of climatic aridification that affected fluvial systems through the weakening of the vegetation cover and the accentuation of the hydrological discharge regime. Corresponding patterns have been found for the time intervals between 8 and 7 ka, 5 and 3.8 ka, 2.2 and 1.5 ka, as well as around 1 ka and 0.4 ka cal. BP. The supra-regional effectiveness of the factor climate is contrasted by a strong regional individuality of the river catchments that is expressed by further, regionally limited phases of fluvial activity. Crucial to this development – apart from regional climate differences – are, inter alia, tectonic movements as evidenced for the Jarama River system in central Spain, or late Pleistocene and Holocene sea-level fluctuations that primarily affected fluvial dynamics along the lower course of the Guadalete River in southwestern Spain. Furthermore, it can be shown that variations in time and duration of fluvial system response are attributable to differing buffer capacities of river catchments towards external influences. The increase of human impact during the late Holocene apparently provoked a reinforcement of the effects of climatic impulses. There are clear evidences for the participation of humans in the mobilization of sediments; however, concerning the degree of influence it is hardly possible to differentiate between the factors humans and climate.:1 Introduction 1.1 Relevance of fluvial records in the context of climate change and landscape evolution in the Western Mediterranean 1.2 Environmental significance of fluvial deposits 1.3 Objectives and methodological approach 2 Late Quaternary fluvial dynamics of the Jarama River 2.1 Introduction 2.2 Study area 2.2.1 Geological and tectonic background 2.2.2 Geomorphological setting of the Jarama valley 2.3 Methods 2.4 Fluvial architecture and characteristics of the sedimentary units 2.4.1 Sequence 1 – Late Pleistocene 2.4.2 Sequence 2 – Early to Mid-Holocene 2.4.3 Sequence 3 – Mid-Holocene to Roman period 2.4.4 Sequence 4 – Little Ice Age 2.5 Interpretation - Stages of floodplain development 2.5.1 Extensive aggradations during Marine Isotope Stage (MIS) 3 2.5.2 Increased fluvial activity in the course of the Last Glacial Maximum (LGM) 2.5.3 Sand deposits (Unit 3) at the end of MIS 2 2.5.4 Younger Dryas and Early to Mid-Holocene sedimentation 2.5.5 Mid-Holocene warm period and climatic collapse 2.5.6 Highly dynamic floodplain aggradations and 3.0 ka-aridity crisis 2.5.7 Extensive sand deposition at 2.8 ka BP and following floodplain stability 2.5.8 Flood loam accumulation during the Roman epoch 2.5.9 Alternating flood loam accumulation and soil formation during the Medieval period 2.5.10 Accentuated fluvial dynamics during the Little Ice Age and recent flooding 2.6 Human influence versus climatic control factors 2.7 Significance of fluvial records in a spatial context 2.8 Conclusion 3 Late Pleistocene and Holocene fluvial dynamics of the lower Guadalete River 3.1 Introduction 3.2 Study area 3.3 Methods 3.4 Stratigraphic findings and sedimentation patterns within the Guadalete valley 3.4.1 Upper downstream section 3.4.1.1 Late Pleistocene sediments 3.4.1.2 Mid-Holocene sediments (5000 - 2000 cal. a BP) 3.4.1.3 Late Holocene sediments (<2000 cal. a BP) 3.4.1.4 Composite profile 3.4.2 Lower downstream section close to the estuary 3.4.2.1 Early Holocene sediments (~10000 - 8000 cal. a BP) 3.4.2.2 Mid- to late-Holocene sediments (<8000 cal. a BP) 3.5 Interpretation – Floodplain evolution and the influencing factors 3.5.1 Stages of floodplain evolution 3.5.1.1 Late Pleistocene dynamics (SU-1 to SU-3) 3.5.1.2 Early Holocene dynamics (SU-4 to SU-7) 3.5.1.3 Mid-Holocene dynamics (SU-8) 3.5.1.4 Mid-Holocene aridity collapse (SU-9a to SU-9c) 3.5.1.5 Late Holocene dynamics (SU-10 to SU-12) 3.5.1.6 Increased dynamics during the Little Ice Age (LIA) (SU-13a to SU-14) 3.6 Conclusion 4 Western Mediterranean environmental changes 4.1 Introduction 4.2 Study area 4.2.1 Jarama River 4.2.2 Guadalete River 4.2.3 Guadalquivir River 4.3 Methods 4.4 Results 4.4.1 Stratigraphic findings of the Jarama River 4.4.1.1 Fluvial architecture 4.4.1.2 Sedimentation patterns 4.4.1.3 Periods of soil formation 4.4.2 Stratigraphic findings of the Guadalete River 4.4.2.1 Fluvial architecture 4.4.2.2 Sedimentation patterns 4.4.2.3 Periods of soil formation 4.4.3 Stratigraphic findings of the Guadalquivir River 4.4.3.1 Fluvial architecture 4.4.3.2 Sedimentation patterns 4.4.3.3 Periods of soil formation 4.5 Discussion 4.5.1 General view of fluvial architectural patterns as basis for interpretations 4.5.2 Fluvial dynamic patterns and possible forcing mechanisms 4.5.3 The role of climate in triggering fluvial dynamics 4.5.4 Supra regional comparison of examined floodplain records 4.5.5 Variability of fluvial dynamics: A matter of sensitivity? 4.5.6 Large-scale consideration of Western Mediterranean fluvial records 4.5.7 Interrelations between North Atlantic sea surface temperature and landscape dynamics on the Iberian Peninsula 4.5.8 Landscape dynamics and corresponding atmospheric conditions 4.6 Conclusion Acknowledgements References 5 Synthesis 5.1 General architectural patterns of examined river floodplains in Spain 5.2 Assessment of influencing factors and their relevance for fluvial dynamics 5.3 Interpretations in terms of palaeo-environmental conditions 5.4 Comparative consideration of the various study areas 5.5 Climate change and implications for fluvial system behavior 5.6 Outlook References / Der westliche Mediterranraum gilt als landschaftlich und klimatisch hochsensible Region, für deren semiaride bis semihumide Gebiete bereits kleinere klimatische Änderungen, aber auch Eingriffe des Menschen, mit weitreichenden Folgen für Umwelt und ökologische Systeme verbunden sein können. Forschungen zum Landschaftswandel nehmen hier vor allem vor dem Hintergrund des derzeitigen Klimawandels einen hohen Stellenwert in den Geowissenschaften ein. Ein wichtiges Anliegen ist dabei, in früheren Landschaftswandeln Muster zu entdecken, welche als Grundlage für Bewertungen zukünftiger Veränderungen dienen können. Für die Rekonstruktion spätquartärer Umweltbedingungen kommt fluvialen Sedimenten eine besondere Rolle zu. Wie kein anderes Archiv spiegeln fluviale Sedimentabfolgen Landschaftszustände und -entwicklung auf regionaler Ebene wieder. Dies ist dem Umstand geschuldet, dass fluviale Dynamik mit allen inbegriffenen Prozessen auf polykausalen Zusammenhängen beruht und somit eine Vielzahl an Faktoren, wie klimatische Verhältnisse und Vegetationsentwicklung, menschliche Einflussnahme oder tektonische Aktivität Ausdruck in fluvialer Dynamik finden. Von feuchten atlantischen Luftmassen geprägte Gebiete nehmen etwa 70 % der Fläche der Iberischen Halbinsel ein, allerdings besteht hier eine erhebliche Forschungslücke im Bereich der Analyse fluvialer Archive. Diesem Umstand soll in vorliegender Dissertation in Form einer systematischen Aufarbeitung der fluvialen Sedimentabfolgen zweier Flusssysteme in Zentralspanien (Rio Jarama), sowie in SW-Spanien (Rio Guadalete) Rechnung getragen werden. Für ergänzende Betrachtungen werden dabei erste Befunde zur stratigraphischen Gliederung des Guadalquivir-Mittellaufes in S-Spanien herangezogen. Ziel der Arbeiten ist es zunächst über umfangreiche Aufnahmen und Dokumentationen von Sedimentprofilen ein belastbares Standardprofil für jedes Flusssystem zu erarbeiten und dieses hinsichtlich der Aussagekraft in Bezug auf Paläoumweltbedingungen und vor allem -wandeln zu prüfen. Neben der möglichen Reaktion fluvialer Systeme auf klimatische Änderungen, stehen dabei vor allem auch Beziehungsgeflechte zu anderen Einflussfaktoren im Vordergrund. Anhand eines überregionalen Vergleichs soll eine mögliche Kopplung fluvialmorphologischer Systeme an großräumige Klimafluktuationen untersucht werden, zudem soll weiteren Themenkomplexen, wie der Konnektivität verschiedener Systeme oder unterschiedlichen Reaktionszeiten und -geschwindigkeiten nachgegangen werden. Grundlage für diese Betrachtungen bilden dabei aus zahlreichen Geländeaufnahmen resultierende Profilaufnahmen, sowie Ergebnisse geoelektrischer Messungen und Bohrsondierungen. Stratigraphische Arbeiten belaufen sich zunächst auf die Untergliederung verschiedener Sedimenteinheiten, die Ausweisung von Bodenhorizonten, sowie die Korrelation einzelner Schichten und Horizonte über unterschiedliche Profile hinweg anhand charakteristischer sedimentologischer und pedogenetischer Merkmale. Nachfolgende bodenchemische und sedimentologische Laboruntersuchungen an ausgewählten Profilen sollen über die Bestimmung von Korngrößenverhältnissen, Gehalten an organischem Kohlenstoff, Kalk- und Eisengehalten, sowie der magnetischen Suszeptibilität die Geländebefunde stützen und in unklaren Fällen eine Unterscheidung von Böden und Bodensedimenten erleichtern. Die zeitliche Auflösung der Sedimentabfolgen soll über Radiokarbondatierungen realisiert werden, mit dem letztendlichen Ziel, eine detaillierte fluviale Sedimentationsgeschichte für das Spätquartär zu erarbeiten. In einem weiteren Schritt werden begleitend zu einer detaillierten Einzugsgebietscharakteristik die chronostratigraphischen Befunde einem intensiven Vergleich mit in der Literatur verfügbaren Studien an Sekundärarchiven zugeführt, um Beziehungsgeflechte zwischen fluvialer Dynamik und verschiedenen Einflussfaktoren aufzudecken. Im Rahmen dieser Dissertation konnten zunächst 36 Profilaufschlüsse detailliert bearbeitet und zudem 13 Rammkernsondierungen in Flussauenpositionen abgeteuft werden. Für den chronologischen Rahmen wurden 70 Radiokohlenstoffproben datiert. Die Ergebnisse zeigen ein deutliches Muster von Sedimentationsphasen und Zeiten der Stabilität mit einhergehender Bodenbildung für jedes Flusseinzugsgebiet. Dabei konnte die Sedimentationsgeschichte der Flusssysteme Rio Guadalete und Rio Guadalquivir für die letzten 15.000 Jahre und des Rio Jarama für die letzten 43 ka rekonstruiert werden. Dank der Fülle an verfügbaren Studien an terrestrischen Vergleichsarchiven mit klima- und umweltrelevantem Bezug war es möglich, den Einfluss der unterschiedlichen Parameter Klima, Vegetation, Mensch und Tektonik, bzw. Erosionsbasis auf die fluviale Sedimentationsdynamik zu prüfen. So zeigte sich, dass vor allem rasche Klimaänderungen in der Lage waren die Mobilisierung von Sedimenten im Einzugsgebiet und deren Ablagerung in den Flussauen zu initiieren. Dahingegen bewirkten anhaltende klimatische Gunstphasen eine Stabilisierung mit einhergehender Bodenbildung, wie für die Zeiträume zwischen 13.3 und 12.7 ka, 7 und 5.1 ka, 2.8 und 2.3 ka, 1.4 und 1.2 ka, sowie 0.8 und 0.5 ka cal. BP für sämtliche Flusssysteme zu verzeichnen ist. Perioden verstärkter Sedimentation folgten in der Regel Phasen klimatischer Aridifizierung, welche über eine Schwächung der Vegetationsbedeckung und Akzentuierung des hydrologischen Abflussregimes in der Lage waren auf das fluviale System Einfluss zu nehmen. Entsprechende Muster konnten für die Zeiträume zwischen 8 und 7 ka, 5 und 3.8 ka, 2.2 und 1.5 ka, sowie um 1 ka als auch 0.4 ka cal. BP dokumentiert werden. Dem überregional wirksamen Einfluss des Faktors Klima steht jedoch eine starke landschaftsgeschichtliche Individualität der verschiedenen Regionen gegenüber, welche in weiteren, regional begrenzten Phasen fluvialer Aktivität zum Ausdruck kommt. Ausschlaggebend sind hier neben der Ausbildung regionaler Klimaunterschiede unter Anderem tektonische Verstellungen, welche für das in Zentralspanien gelegene System des Rio Jarama belegt werden konnten, oder spätpleistozäne und holozäne Meeresspiegelschwankungen, welche sich vor allem auf die fluviale Dynamik im Unterlauf des in SW-Spanien gelegenen Rio Guadalete auswirkten. Desweiteren können Unterschiede in Reaktionsdauer und -geschwindigkeit fluvialer Systeme mit variierendem Puffervermögen der Flusseinzugsgebiete gegenüber äußeren Einflüssen erklärt werden. Das intensivierte Wirken des Menschen im Spätholozän führte allem Anschein nach zu einer Verstärkung der Wirkung klimatischer Impulse, wobei sich klare Evidenzen für eine Beteiligung des Menschen an der Sedimentmobilisierung erkennen lassen, der Umfang des Einflusses des Menschen aber in der Regel nicht klar von dem des Klimas zu trennen ist.:1 Introduction 1.1 Relevance of fluvial records in the context of climate change and landscape evolution in the Western Mediterranean 1.2 Environmental significance of fluvial deposits 1.3 Objectives and methodological approach 2 Late Quaternary fluvial dynamics of the Jarama River 2.1 Introduction 2.2 Study area 2.2.1 Geological and tectonic background 2.2.2 Geomorphological setting of the Jarama valley 2.3 Methods 2.4 Fluvial architecture and characteristics of the sedimentary units 2.4.1 Sequence 1 – Late Pleistocene 2.4.2 Sequence 2 – Early to Mid-Holocene 2.4.3 Sequence 3 – Mid-Holocene to Roman period 2.4.4 Sequence 4 – Little Ice Age 2.5 Interpretation - Stages of floodplain development 2.5.1 Extensive aggradations during Marine Isotope Stage (MIS) 3 2.5.2 Increased fluvial activity in the course of the Last Glacial Maximum (LGM) 2.5.3 Sand deposits (Unit 3) at the end of MIS 2 2.5.4 Younger Dryas and Early to Mid-Holocene sedimentation 2.5.5 Mid-Holocene warm period and climatic collapse 2.5.6 Highly dynamic floodplain aggradations and 3.0 ka-aridity crisis 2.5.7 Extensive sand deposition at 2.8 ka BP and following floodplain stability 2.5.8 Flood loam accumulation during the Roman epoch 2.5.9 Alternating flood loam accumulation and soil formation during the Medieval period 2.5.10 Accentuated fluvial dynamics during the Little Ice Age and recent flooding 2.6 Human influence versus climatic control factors 2.7 Significance of fluvial records in a spatial context 2.8 Conclusion 3 Late Pleistocene and Holocene fluvial dynamics of the lower Guadalete River 3.1 Introduction 3.2 Study area 3.3 Methods 3.4 Stratigraphic findings and sedimentation patterns within the Guadalete valley 3.4.1 Upper downstream section 3.4.1.1 Late Pleistocene sediments 3.4.1.2 Mid-Holocene sediments (5000 - 2000 cal. a BP) 3.4.1.3 Late Holocene sediments (<2000 cal. a BP) 3.4.1.4 Composite profile 3.4.2 Lower downstream section close to the estuary 3.4.2.1 Early Holocene sediments (~10000 - 8000 cal. a BP) 3.4.2.2 Mid- to late-Holocene sediments (<8000 cal. a BP) 3.5 Interpretation – Floodplain evolution and the influencing factors 3.5.1 Stages of floodplain evolution 3.5.1.1 Late Pleistocene dynamics (SU-1 to SU-3) 3.5.1.2 Early Holocene dynamics (SU-4 to SU-7) 3.5.1.3 Mid-Holocene dynamics (SU-8) 3.5.1.4 Mid-Holocene aridity collapse (SU-9a to SU-9c) 3.5.1.5 Late Holocene dynamics (SU-10 to SU-12) 3.5.1.6 Increased dynamics during the Little Ice Age (LIA) (SU-13a to SU-14) 3.6 Conclusion 4 Western Mediterranean environmental changes 4.1 Introduction 4.2 Study area 4.2.1 Jarama River 4.2.2 Guadalete River 4.2.3 Guadalquivir River 4.3 Methods 4.4 Results 4.4.1 Stratigraphic findings of the Jarama River 4.4.1.1 Fluvial architecture 4.4.1.2 Sedimentation patterns 4.4.1.3 Periods of soil formation 4.4.2 Stratigraphic findings of the Guadalete River 4.4.2.1 Fluvial architecture 4.4.2.2 Sedimentation patterns 4.4.2.3 Periods of soil formation 4.4.3 Stratigraphic findings of the Guadalquivir River 4.4.3.1 Fluvial architecture 4.4.3.2 Sedimentation patterns 4.4.3.3 Periods of soil formation 4.5 Discussion 4.5.1 General view of fluvial architectural patterns as basis for interpretations 4.5.2 Fluvial dynamic patterns and possible forcing mechanisms 4.5.3 The role of climate in triggering fluvial dynamics 4.5.4 Supra regional comparison of examined floodplain records 4.5.5 Variability of fluvial dynamics: A matter of sensitivity? 4.5.6 Large-scale consideration of Western Mediterranean fluvial records 4.5.7 Interrelations between North Atlantic sea surface temperature and landscape dynamics on the Iberian Peninsula 4.5.8 Landscape dynamics and corresponding atmospheric conditions 4.6 Conclusion Acknowledgements References 5 Synthesis 5.1 General architectural patterns of examined river floodplains in Spain 5.2 Assessment of influencing factors and their relevance for fluvial dynamics 5.3 Interpretations in terms of palaeo-environmental conditions 5.4 Comparative consideration of the various study areas 5.5 Climate change and implications for fluvial system behavior 5.6 Outlook References