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River landscapes have an important function in the landscape in terms of coastal use and the opportunities they provide and they offer different cultural ecosystem services (CES). CES have a significant impact on human welfare in terms of the recreational, aesthetic and spiritual benefits these generate for people. However, the modelling and analysis of these services is more limited versus other ecosystem services due to their intangibility and subjectivity which creates unique challenges. Recently, social media data have provided an opportunity to generate spatial models of CES, offering significant cost and time advantages. Nevertheless, the usefulness of these novel data sources still requires more investigation versus more traditional survey techniques. This study aims to understand the variety of information provided by the images that users upload publicly on a daily basis to social media in a urban/rural setting. Specifically, CES provided by the open and green spaces around the Lower Rhine (Nederrijn) in Wageningen were studied using images uploaded to the social media platform Flickr. A photographic survey was then conducted to compare the utility and accuracy of these new data versus traditional techniques. In doing so, spatial data, ratings and survey evaluations related to the photographs were digitised, classified and integrated with land cover features. The results show that there is a good consistency between the two sources of data and that a wide range of CES measures can be established using these novel data sources. More work is now needed in developing spatial indicators of CES relevant to local assessments, such as the one carried out in this study. Focusing on the Lower Rhine region as a case study, we used the Flickr digital platform to address the following three key questions: (1) What is the spatial distribution of CES? (2) Do users who post on the Flickr platform fully represent the cultural identity of the community and visitors in the region? (3) Which land-cover types of the Lower Rhine region are most appreciated for CES and what are the aesthetic preferences of visitors and experts that correspond to this?

This thesis examines the largest floods of the Lower Rhine river over the past centuries to millennia (Late Holocene to historic time frame). Its central objective is to quantify these events. First, the thesis determines maximum water levels in the past based on sedimentological interpretation of archaeological stratigraphy and geographical survey of epigraphic marks. Next, it provides detailed reconstructions of the alluvial terrain of the Lower Rhine valley and delta, covering the early modern channel bathymetry restored from historic maps and the medieval floodplain topography restored from geomorphological analysis and interpolation. The past landscape context then serves to set up a palaeoflood hydraulic model that resolves the discharges of the largest floods by linking the simulation results to reconstructed water levels. The insights gained in this thesis may ultimately contribute to the design of future flood protection measures. The overarching findings demonstrate that reliable quantification of past floods in lowland river settings necessitates a two-dimensional approach, when it comes to the required flood level and landscape reconstructions and the discharge calculations. Furthermore, the findings show that palaeoflood research benefits from a multidisciplinary approach, with the primary methodological focus depending on the selected casus and targeted time period. The results include successfully reconstructed pre-instrumental flood levels across the Lower Rhine valley and delta by integrating archaeological, geological, and historical sources (Chapters 2, 3, and 6). Additionally, the results encompass successful reconstructions of the landscape for two key periods: before the onset of river normalisation in the mid-nineteenth century and before the onset of embankment in medieval times (Chapters 4 and 5). Finally, the thesis provides an estimate for the ‘millennial’ discharge in the Late Holocene by numerical flood simulations in the pre-embanked landscape context, resulting in a value of 14,000 m3/s (Chapter 6). Further output of the Floods of the Past, Design for the Future project shows that the landscape context prior to normalisation is crucial to constraining discharge magnitudes of individual historic flood events.

Concern about fisheries impact on marine ecosystems has raised the interest in the reconstruction of the state of marine ecosystems and the nature of the human activities in the past. We present late 16th century information on the occurrence and relative abundance of biota in Dutch coastal and inland waters (50 marine fish, 13 diadromous or freshwater and 4 marine mammal species), as well as a description of the sea fisheries (target species, fishing grounds, gear), fish trade, export, and fish consumption in Holland as documented in the handwritten Fish Book by Adriaen Coenen (1577–1581). The species composition and abundances are compared to published trawl survey data from around 1900 and in the 1990s. Fish species that have disappeared almost completely, were already rare around 1900 and are characterised by a large body size (rays and sharks, sturgeon, ling), whereas currently abundant species were already abundant in the 16th century. Intensive fisheries for herring occurred near Orkney, Fairhill and Shetland. Coastal and freshwater fisheries provided fresh fish for local as well as export markets, but also provided bait for the massive offshore hook and line fishery for the production of salted cod, which remained largely unnoticed. Dried flatfish were exported to Germany. Consumption of fish and marine invertebrates differed between social classes. Coenen distinguished eight consumer categories, a refinement of the categories ‘rich’ and ‘poor’ used in archaeological studies.

North Sea houting, Coregonus oxyrinchus, became extinct in the River Rhine in the 1940 s and was reintroduced in the 1990 s. To study the migration history of individuals, the 88Sr:44Ca ratio of scales of 39 houting (10–44 cm TL) caught in Lake IJsselmeer was analysed using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Scales of houting inhabiting freshwater ponds and two Danish rivers containing the last original populations in the North Sea basin were used as controls. Fish that lived exclusively in freshwater had 88Sr:44Ca ratios of around 0.2 from the nucleus to the edge; 29 of the analysed houting from Lake IJsselmeer were of this type. Most of these were small, but some were mature and up to 42 cm in length. Seven houting had 88Sr:44Ca ratios over 0.27 from the nucleus to the scale maximum values, indicating migration to the sea at early life stages. Three houting with low 88Sr:44Ca ratios at the scale nucleus and increased 88Sr:44Ca ratios towards the scale edge probably lived in freshwater for a longer period after hatching and then moved to brackish/marine environments. The scale analysis indicates different migration patterns for houting in Lake IJsselmeer and provides evidence that this species (1) is sometimes able to pass the migratory barriers between the Wadden Sea and Lake IJsselmeer, and (2) does not need to migrate to sea to reach maturity.

Anadromous North Sea houting (NSH, Coregonus oxyrinchus) was historically distributed in the Wadden Sea extending from Jutland (Denmark) to the Schelde delta (Netherlands). The species has been considered extinct in the Rhine since the 1940s; however, a successful re-introduction programme re-established a self-reproducing population. Telemetry data of adult NSH (NEDAP TRAIL System®) were used for a first description of the timing of spawning migrations of NSH in winter, but also suggested that the River IJssel, a lower branch of the Rhine, may serve as spawning ground. This was further proven in spring 2010 with drift net catches of 218 freshly hatched NSH larvae sampled directly upstream from Kampen, where the IJssel discharges into Lake IJsselmeer. These larvae did not differ between controls from a hatchery that were about 12 h of age, indicating that the drifting larvae of NSH must have hatched in upstream areas of the River IJssel.

A Chézy-based hydraulic model was run to estimate the magnitude of extreme floods of Middle Holocene age in the Lower Rhine Valley (Germany). Input parameters were gathered from the field and literature, and used in ten scenarios to calculate a best guess estimate for the minimum size of extreme floods. These events have been registered as slackwater deposits on elevated terrace levels and in a palaeochannel fill. The modelled minimum discharge is 13,250 m3 sec-1 for a Middle Holocene flood with an estimated recurrence interval between 1,250 and 2,500 years. A sensitivity analysis on different input parameters enables evaluation of factors which cause the relatively large range in modelled discharges. Understanding the origin of uncertainties in modelled discharges is important for making geologically based calculations of palaeoflood magnitudes important in modern flood frequency analyses, which generally lack information on the magnitudes of rare events. © 2013 IWA Publishing.

A Chézy-based hydraulic model was run to estimate the magnitude of extreme floods of Middle Holocene age in the Lower Rhine Valley (Germany). Input parameters were gathered from the field and literature, and used in ten scenarios to calculate a best guess estimate for the minimum size of extreme floods. These events have been registered as slackwater deposits on elevated terrace levels and in a palaeochannel fill. The modelled minimum discharge is 13,250 m3 sec-1 for a Middle Holocene flood with an estimated recurrence interval between 1,250 and 2,500 years. A sensitivity analysis on different input parameters enables evaluation of factors which cause the relatively large range in modelled discharges. Understanding the origin of uncertainties in modelled discharges is important for making geologically based calculations of palaeoflood magnitudes important in modern flood frequency analyses, which generally lack information on the magnitudes of rare events. © 2013 IWA Publishing.

In the Weichselian, the Lower Rhine in the Dutch-German border region has used three courses, dissecting ice-marginal topography inherited from the Saalian. In the Late Weichselian, the three courses functioned simultaneously, with the central one gaining importance and the outer ones abandoning. This study aims to reconstruct the fluvial development and forcings that culminated in abandonment of the northern branch ‘Oude IJssel-Rhine’, at the time of the Lateglacial to Holocene transition. The fluvial architecture is studied using a cored transect over the full width of the valley, detailed cross-sections over palaeochannels and geomorphological analysis using digital elevation and borehole data. Biostratigraphy, radiocarbon dating and OSL dating provide a timeframe to reconstruct the temporal fluvial development. In its phase of abandonment, the fluvial evolution of the Oude IJssel-Rhine course is controlled by the ameliorating climate and related vegetation and discharge changes, besides by intrinsic (autogenic) fluvial behaviour such as the competition for discharge with the winning central branch and the vicinity of the Lippe tributary confluence. The rapid climate warming at the start of the Late Glacial resulted in flow contraction as the initial response. Other fluvial geomorphic adjustments followed, with some delay. An aggrading braided or transitional system persisted until the start of the Allerod, when channel patterns finally changed to meandering. Floodplain incision occurred at the Allerod - Younger Dryas transition and a multi-channel system developed fed by Rhine discharge. At the start of the Holocene, this system transformed into a small-scale, local meandering system, which was abandoned shortly after the start of the Holocene. The final abandonment of the Oude IJssel-Rhine and Niers-Rhine courses can be attributed to deep incision of the Central Rhine course in the earliest Holocene and is considered to be controlled by flow contraction induced by climate and related vegetation and discharge changes.

In the Weichselian, the Lower Rhine in the Dutch-German border region has used three courses, dissecting ice-marginal topography inherited from the Saalian. In the Late Weichselian, the three courses functioned simultaneously, with the central one gaining importance and the outer ones abandoning. This study aims to reconstruct the fluvial development and forcings that culminated in abandonment of the northern branch ‘Oude IJssel-Rhine’, at the time of the Lateglacial to Holocene transition. The fluvial architecture is studied using a cored transect over the full width of the valley, detailed cross-sections over palaeochannels and geomorphological analysis using digital elevation and borehole data. Biostratigraphy, radiocarbon dating and OSL dating provide a timeframe to reconstruct the temporal fluvial development. In its phase of abandonment, the fluvial evolution of the Oude IJssel-Rhine course is controlled by the ameliorating climate and related vegetation and discharge changes, besides by intrinsic (autogenic) fluvial behaviour such as the competition for discharge with the winning central branch and the vicinity of the Lippe tributary confluence. The rapid climate warming at the start of the Late Glacial resulted in flow contraction as the initial response. Other fluvial geomorphic adjustments followed, with some delay. An aggrading braided or transitional system persisted until the start of the Allerød, when channel patterns finally changed to meandering. Floodplain incision occurred at the Allerød - Younger Dryas transition and a multi-channel system developed fed by Rhine discharge. At the start of the Holocene, this system transformed into a small-scale, local meandering system, which was abandoned shortly after the start of the Holocene.The final abandonment of the Oude IJssel-Rhine and Niers-Rhine courses can be attributed to deep incision of the Central Rhine course in the earliest Holocene and is considered to be controlled by flow contraction induced by climate and related vegetation and discharge changes.

Auf der Basis einer detaillierten Lössstratigraphie wurden auf dem Lössplateau des westlichen Niederrheins von einer Abbauwandgesamtfläche von 11.000qm die Anteile der wichtigsten Lösseinheiten berechnet. Darin nimmt der Brabant-Löss (spätes Jüngeres Hochwürm, MIS 2) 45% Anteil ein, also nahezu die Hälfte des vorhandenen Lösses, der Hesbaye-Löss (frühes Jüngeres Hochwürm, MIS2) etwa 5%. Ein Viertel des Lösses (25%) geht an den Keldach-Löss (Älteres Hochwürm, MIS4), nur wenig (1,5%) an den Rheingau-Löss (MIS 5). Dem Prä-Eem-Löss gehört das letzte Viertel (24%) desgesamten Lösses. Eine statistische Suche nach prähistorischen Funden erbrachte 131 paläolithische Knochen und Artefakte, die stratigraphisch genau zugeordnet werden konnten. Die Hauptmasse der Funde gehört den beiden Stadien MIS4 und MIS2 an – bemerkenswerterweise zwei kalten Perioden. Das Fehlen interglazialer Funde – solche sind vom übrigen Lössplateau durchaus bekannt – wird der starken periglazialen Abtragung und Einebnung in Plateauposition zugeschrieben. Die vorliegenden Funde belegen erstmals lokale Jagdaktivität während feuchter Perioden im Stadium MIS4. Ob die Funde aus dem MIS2 autochthon sind oder aus älteren Schichten aufgearbeitet wurden, muss offen bleiben., research

Trois figures illustrent cet article, complété par un court lexique.; International audience; Over twenty-first century, the aging issue will be central in Europe as in the world. In France in 2030, according to average projections, the population of France should age, the number of seniors is expected to grow and the dependent elderly people also. But, first, these developments would be very different according to territories including their urban or rural character. Moreover, the pace of these developments would be discontinuous.; Au fil du, la question du vieillissement sera centrale en Europe comme dans le monde. En France, à l'horizon 2030, selon les projections moyennes, la population de la France devrait vieillir, le nombre des personnes âgées devrait progresser et celui des personnes âgées dépendantes également. Mais, d'une part, ces évolutions seraient très différenciées selon les territoires et notamment leur caractère urbain ou rural. D'autre part, le rythme de ces évolutions serait discontinu.

Key variables in ecosystems tend to operate on widely different time-scales. These time-scales become relevant when a disturbance rocks the ecosystem. Here we try to explain the fast dynamics of plankton and nutrients in the water column of floodplain lakes after disturbances (inundations). We take advantage of natural experiments, that is occasional massive overflow of floodplain takes with river water. We sampled 10 lakes in two floodplains along the Dutch river Waal monthly for 3 years, capturing the impact of three inundation events. The inundations reset the plankton as well as chemical composition of most lakes to largely the same state. While biologically inert macro-ion data reflected a large and long lasting impact of the river water, dynamics of nutrients, phytoplankton and zooplankton communities between lakes diverged in a few weeks to regimes characteristic for the different lakes. While one spring inundation synchronized plankton dynamics to let the subsequent clear water phase occur at the same moment in different lakes, winter inundations did not have the same effect and apparently dynamics quickly diverged. Our results showed that effects of inundations and other processes that affect the state of the ecosystem should be studied considering the level of the slow components such as the sediment nutrient pool, fish stock and macrophyte communities. Plankton communities and take water nutrient status give a practically instantaneous reflection of the condition of these slow components. Copyright (C) 2008 John Wiley & Sons, Ltd.