SMHI:s hydrologiska prognos- och varningstjänst använder sig av meteorologiska ensembleprognoser som indata i hydrologiska modeller. De hydrologiskaensembleprognoserna tar därmed hänsyn till framtida osäkerhet i temperatur och nederbördoch används som underlag vid utfärdandet av risker och varningar för höga flöden. För närvarande beaktas dock inte osäkerheten i modellens starttillstånd, vilket består av de tillståndsvariabler i modellen som beskriver bland annat markvattenhalt och snötäcke. I dennastudie undersöktes hur starttillståndet i den hydrologiska modellen HYPE inverkar på prognoser i syfte att kvantifiera osäkerheten och på sikt möjliggöra säkrare prognoser.Studien hade tre mål: 1) Ta fram ett förslag på hur starttillståndet kan varieras för att ge en god uppskattning av prognososäkerheten relaterat till det hydrologiska starttillståndet. 2) Undersöka sambandet mellan starttillståndens spridning och det hydrologiska prognosfelet. 3) Analysera hur årstider, avrinningsområdens area, sjöprocent, skogsprocent och höjd över havet inverkar på prognososäkerheten. En central hypotes var att mindre skillnad mellan starttillståndets vattenföring och den observerade vattenföringen vid prognosstart resulterar i mer träffsäkra prognoser. Studien begränsades av att starttillstånden endast genererades med hjälp av störningar i drivdata.Indata till HYPE-modellen var femton temperatur- och nederbördsserier som manipulerats i syfte att skapa en ensemble av olika starttillstånd. Denna ensemble användes sedan för att göra vattenföringsprognoser med observerad temperatur och nederbörd som drivdata. Studien omfattade 76 avrinningsområden från hela Sverige med data för perioden 1999-2008. Prognoser utfördes varje dygn och ensemblespridningen utvärderades 2, 4 och 10 dygn in i prognosen. Samma utvärderingar utfördes även på autoregressiva prognoser, vilket innebär att modellerad rättas utefter observerad vattenföring.Resultaten indikerade ett samband mellan ensemblespridning och prognosfel, vilket innebär att spridning kan användas som ett mått på starttillståndets osäkerhet. Prognosfelet korrelerade positivt med skogsprocent och negativt med avrinningsområdenas area, sjöprocent och höjd över havet. Samma samband uppvisades mellan dessa områdesvariableroch spridning. Spridningen var störst på vintern och våren då normalisering skett med medelvattenföring över tio år, och under vår och sommar då normalisering skett med medelvattenföring per månad. Hypotesen att mindre skillnad mellan starttillståndets vattenföring och den observerade vattenföringen vid prognosstart resulterar i mer träffsäkraprognoser bekräftades av resultaten. Implementering av en ensemble av olika starttillstånd i operationella prognoser vid SMHIs hydrologiska prognos- och varningstjänst föreslås i syfte att kvantifiera osäkerheten och därigenom utöka bedömningsunderlaget vid utfärdande av risker och varningar. / The Hydrological Forecast and Warning Service of The Swedish Meteorological and Hydrological Institute (SMHI) use meteorological ensemble forecasts as input in hydrological models. The hydrological ensemble forecasts take the uncertainty of future temperature and precipitation into account and serve as the basis of issued risks and warnings of high flows. Currently not considered is the uncertainty of the initial state, which consists of state variables in the model describing for instance soil water content and snow pack. This study assessed the impact of the initial state on forecasts in the hydrological model HYPE aiming to quantify the uncertainty and eventually enable more accurate forecasts.There were three aims of this study : 1) Evaluate a suggestion about how the initial state can be varied to give a good estimation of forecast uncertainty related to the hydrological initial state. 2) Examine the relationship between the spread of initial states and the hydrological forecast error. 3) Analyze the impact of seasons, catchment area, lake percentage, forest percentage and elevation on forecast uncertainty. A central hypothesis was that a smaller difference between the discharge of the initial state and the observed discharge results in more accurate forecasts. A restriction of the study was that the initial states only could be generated by disturbances of forcing data in before the forecast.Input data to the HYPE model were fifteen temperature and precipitation series, manipulated to generate an ensemble of different initial states. This ensemble was then used to make discharge forecasts with observed temperature and precipitation as forcing data. The study was performed on 76 catchments all over Sweden with data from the time period 1999-2008. Forecasts were made every day and the ensemble spread was evaluated 2, 4 and 10 days into the forecast. Autoregressive forecasts where the modelled discharge is corrected after the observed discharge were executed and evaluated as well. The results indicated a relationship between ensemble spread and forecast error, which implies that the spread can be used as a measure of the uncertainty of the initial state. The forecast error and ensemble spread correlated positively to forest percentage and negatively to catchment area, lake percentage and elevation. The same trend was detected between spread and catchment characteristics. The spread was biggest in winter and spring when normalization was made with mean discharge for the ten-year period and in spring and summer when normalization was done with mean discharge per month. The hypothesis that a smaller difference between the discharge of the initial state and the observed discharge results in more accurate forecasts was confirmed by the results. An implementation of an ensemble of different initial states in operational forecasts at SMHI’s Hydrological Forecast and Warning Service is suggested in order to further quantify the uncertainty of hydrological forecasts, and thereby improve the basis of judgment when issuing risks and warnings.

L'objectif général de cette thèse est axé sur l’amélioration de modèles agro-hydrologique spatialement distribués pour l’analyse d'agro-hydrosystèmes, sous contrainte de changements climatiques et anthropiques. Cette thèse est structurée autour de trois questions de recherche liées à : i) la représentation de la dynamique spatio-temporelle des systèmes de cultures pour leur utilisation en entrée de modèles agro-hydrologiques distribués ; ii) la représentation du niveau exploitation agricole et des décisions des agriculteurs dans les modèles agro-hydrologiques distribués ; iii) la capacité de ces modèles à simuler des changements climatiques et anthropiquesDes éléments de réponse à ces questions sont apportés par des approches de modélisation réalisées dans différents contextes et à différentes échelles d’espace et de temps. Ces différentes approches sont discutées en les comparant notamment avec d’autres travaux réalisés. Ces différentes études soulèvent la nécessité de développer des méthodologies permettant i) d’une part l’acquisition de données et leur intégration dans les modèles agro-hydrologiques distribués ii) et d’autre part l’amélioration de l’exploitation des simulations, notamment pour les transformer en informations pertinentes et accessibles pour les parties prenantes au niveau d’un territoire. Des perspectives, portant à la fois sur la prise en compte des incertitudes des simulations des modèles agro-hydrologiques et l’analyse de la robustesse de ces modèles, sont également considérées. / The general objective of this thesis is to improve spatially distributed agro-hydrological models for agro-hydrosystems analysis, under climatic and anthropogenic changes, in order to contribute to the identification of levers of action to mitigate effects of non-point source agricultural pollution. This thesis is structured around three research questions related to: i) the representation of spatio-temporal dynamics of cropping systems for their use as input in distributed agro-hydrological models; ii) the representation of farm level and decisions of farmers in distributed agro-hydrological models; and iii) the ability of these models to simulate climate and anthropogenic changes.Elements of response to these questions are provided by modeling approaches carried out in different contexts and at different scales of space and time. These approaches are discussed by comparing them with other works carried out. These different studies raise the need to develop methodologies allowing (i) the acquisition of data and their integration in distributed agro-hydrological models (ii) and, the improvement of the use of simulations results, in particular to transform them into relevant and accessible information for stakeholders at territorial level. Perspectives, covering both uncertainties of the simulations of the agro-hydrological models and the analysis of the robustness of these models, are also considered

Mangrove ecosystems thrive in (sub)tropical, intertidal areas where adaptations<p>like vivipary and the hydrochorous dispersal of propagules become an absolute<p>necessity. As propagule dispersal and early growth allow for the replenishment of<p>existing stands and colonization of new habitats, many authors recognize the<p>importance of these stages in structuring mangrove populations and communities.<p>However, when it comes to the actual propagule dispersal and recruitment<p>mechanisms, there is an apparent lacuna in the current understanding of<p>mangrove ecology. The period between the mature propagule falling from the<p>parental mangrove tree and the early growth of the established seedling, under<p>various possible circumstances, remains in the dark. In this study we focus on this<p>particular period by investigating both the places where these propagules end up<p>as the pathways their dispersal units follow. And we go one step further.<p><p>Mangrove forests are being destroyed worldwide at a threatening pace despite<p>their tremendous asset to coastal human communities and associated biological<p>species. The effect of human-induced (cutting and mangrove conversion to<p>aquaculture ponds) as well as indirectly and/or ‘naturally’ evolving disturbances<p>(sea level rise) on propagule hydrochory occupies an important place in this study.<p><p>Dispersal of water-buoyant propagules of the family Rhizophoraceae and<p>Acanthaceae (now including the Avicenniaceae) was studied in Gazi Bay (Kenya),<p>Galle and the Pambala-Chilaw Lagoon Complex (Sri Lanka). The study sites<p>differ both in tidal regime and vegetation structure, covering an interesting variety<p>of ecological settings to examine propagule dispersal. Field data and experiments<p>ranging from micro/ mesotopographical measurements and successive propagule<p>counts to hydrodynamic and propagule dispersal experiments were collected or<p>executed in situ.<p><p>Two main methodological approaches were employed. Firstly, the question on<p>mechanisms of propagule recruitment was addressed by statistically investigating<p>the effect of microtopography, top soil texture and above-ground-root complexes on<p>the stranding and self-planting of propagules (Chapter 2&3). Afterwards,<p>suitability maps were created using Geographical Information Systems (GIS) to<p>assess whether a particular mangrove stand has the ability to succesfully<p>rejuvenate. Furthermore, the effect of degradation (tree cutting) (Chapter 2&3),<p>sea level rise (Chapter 2&4) and microtopography-altering burrowing activities of<p>the mangrove mud lobster Thalassina anomala (Chapter 3), was incoporated in the<p>GIS-analyses. Secondly, the combined set-up of hydrodynamic modelling and<p>ecological dispersal modelling was developed to simulate propagule dispersal<p>pathways influenced by dispersal vectors (tidal flow, fresh water discharge, wind),<p>trapping agents (retention by vegetation or aerial root complexes) and seed<p>characteristics (buoyancy, obligated dispersal period) (Chapter 5&6). This type of<p>approach provided the possibility to explore propagule dispersal within its<p>ecological context, but was also applied to an implication of shrimp pond area<p>restoration (Pambala-Chilaw Lagoon Complex, Sri Lanka) (Chapter 5) and to<p>evaluate changes in propagule dispersal when sea level rises (Gazi Bay, Kenya)<p>(Chapter 6).<p><p>The main findings regarding propagule recruitment indicate that propagules are<p>not distributed equally or randomly within a mangrove stand, yet species-specific<p>distribution for anchorage occurs. Characteristics of the environment<p>(microtopography, top soil texture and above-ground root complex) influence<p>propagule recruitment in a way that complex root systems (e.g. pencil roots and<p>prop roots) facilitate the entanglement of dispersal units and a more compact soil<p>texture (like clay and silt) and a predominant flat topography creates suitable<p>areas for stranding and self-planting of propagules. This combines effects of<p>existing vegetation and abiotic factors on mangrove propagule establishment.<p>Since propagule dispersal is not solely determined by species-specific propagule<p>characteristics (e.g. buoyancy, longevity, etc.), I emphasize that propagule sorting<p>by hydrochory has to be viewed within its ecological context. Propagule retention<p>by vegetation and wind as a dispersal vector, deserve a prominent role in studies<p>on propagule dispersal. The significance of dense vegetation obstructing long<p>distance dispersal (LDD in its definition of this work), mainly in inner mangrove<p>zones, supports our main finding that propagule dispersal is largely a short<p>distance phenomenon. ‘Largely’ is here understood as quantitatively, not<p>excluding epic colonization events of rare but important nature.<p>In accordance with the Tidal Sorting Hypothesis (TSH) of Rabinowitz (1978a),<p>smaller, oval-shaped propagules were found to disperse over larger distances than<p>bigger, torpedo-shaped propagules. We can however not fully support the TSH<p>because (1) these differences are no longer valid when comparing between torpedoshaped<p>propagules of different sizes and (2) propagule dispersal is not always<p>directed towards areas more inland, but can be strongly concentrated towards the<p>edges of lagoons and channels<p><p>Anthropogenic pressure on mangrove ecosystems, more specifically clear-felling or<p>mangrove conversion to aquaculture ponds, imposes limitations on propagule<p>recruitment due to reduced propagule availability and a decrease in suitable<p>stranding areas where the architecture of certain root complexes, like prop roots<p>and pencil roots, function as propagule traps. These types of pressure appear to<p>have more severe consequences on propagule dispersal than the effect of sea level<p>rise on mangroves. Mangrove forests, which are not situated in an obviously<p>vulnerable setting, can be resilient to a relative rise in sea level if a landward shift<p>of vegetation assemblages and successful early colonization is not obstructed by<p>human-induced pressures. Also, and this renders mangrove forests vulnerable in<p>spite of their intrinsic resilience, when the ‘capital’ of forest is severely reduced or<p>impoverished as happens extensively worldwide, the ‘interest’ on this capital,<p>understood as propagule availability, delivery and trapping, will not allow them to<p>efficiently cope with sea level rise, putting sustainability of mangrove ecosystem<p>services and goods at risk.<p><p>In a larger framework of mangrove vegetation dynamics, knowledge on propagule<p>dispersal will benefit management strategies for the conservation of mangroves<p>worldwide, besides its fundamental interest to fully fathom the ecology of this<p>particular marine-terrestrial ecotone formation. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

L'objectif de la thèse est d'améliorer la compréhension des processus hydrologiques lors des événements de crues éclair. Se basant sur un modèle existant (MARINE), l'étude se concentre sur les processus internes au sol. Une étape préliminaire permet, à partir de l'analyse des données, de confirmer l'activité du socle rocheux durant les crues éclair. Une analyse structurelle de MARINE est réalisée, afin de connaître la sensibilité des flux de subsurface aux choix structurels. Une nouvelle modélisation, plus robuste et intégrant explicitement une représentation des roches altérées, est mise en place. Supposant des chemins préférentiels à l'interface sol/roche, le modèle donne une bonne reproduction des bassins sédimentaires. Sur les bassins granitiques, il sous-estime les récessions et, en conséquence, les éventuels seconds pics de crue, montrant la nécessité de représenter des flux significatifs sur ces bassins, y compris dans la zone altérée. / The purpose of this thesis is to improve the knowledge of hydrological processes during flash flood events using rainfall-runoff modelling. The project focuses on hydrological processes occurring into soil and subsoil horizons. A preliminary data analysis corroborates the activity of the weathered bedrock during flash floods. The hydrological response, simulated by the MARINE model, is then investigated to detect the sensitivity of subsurface flow processes to model assumptions. It leads to several modifications of the model structure in order to make it more robust. Moreover a two-layered soil column is implemented to explicitly integrate the activity of the weathered bedrock into the model. Assuming preferential path flows at the soil-bedrock interface, the model performs well on sedimentary watersheds, but underestimate recession curves and second flood peaks on granitic ones, showing the need to simulate as well significantcontribution from the weathered bedrock.

Der Landschaftswasserhaushalt stellt die Integrationsebene der Geokomponenten Klima, Boden und Landnutzung dar und unterliegt aktuell einer intensiven Forschungstätigkeit. Die charakteristische Ausprägung des Landschaftswasserhaushaltes ist in der mitteleuropäischen Kulturlandschaft das Ergebnis einer von vielfältigen Triebkräften bestimmten komplexen Nutzung. Diese existierenden Nutzungsansprüche werden aber nicht gezielt zur Optimierung des Landschaftswasserhaushaltes koordiniert, da die handelnden Akteure teils völlig gegensätzlichen Zielrichtungen verfolgen. Insgesamt gesehen bietet die Optimierung der nicht besiedelten Landfläche auf Grund ihrer großen Flächeninanspruchnahme die größten Potentiale der Beeinflussung des Landschaftswasserhaushaltes. In der vorliegenden Arbeit werden mit der hydrologischen Modellierung und der funktionalen Landschaftsbewertung zwei völlig unterschiedliche methodische Ansätze zur Analyse hydrologischer Prozesse im Landschaftswasserhaushalt genutzt, um die Reaktion des Wasserhaushaltes auf Landschaftsveränderungen zu untersuchen. Es wird am Beispiel eines Flusseinzugsgebietes im Erzgebirge gezeigt, inwieweit sich durch ein Niederschlag-Abfluss-Modell Änderungen im Wasserhaushalt von Landnutzungsszenarien aufzeigen lassen, die auf der Grundlage von Landschaftsbewertungsverfahren erstellt wurden. Es sollen also mittels hydrologischer Modellierung die qualitativen Resultate eines deutlich einfacher zu realisierenden Planungsverfahrens quantifiziert werden. Auf der Basis der bewerteten Landschaftsfunktionen Abflussregulationsfunktion, Wassererosionswiderstand, Ertragspotential und physikochemisches Filtervermögen des Bodens wurden durch multikriterielle Optimierung mit der Software LNOPT zwei sich unterscheidende Szenarien, ein eher realistisch angelegtes Szenario (Realszenario) und ein Szenario mit möglichst hoher Retentionswirkung (Szenario Abflussminimierung) entwickelt. Beide Szenarien sind an die Realität angelehnt und nicht fiktiv, wodurch sich starke Einschränkungen hinsichtlich der optimierbaren Fläche ergeben. So stehen nur 36,5 % der Gesamtfläche zur Landnutzungsoptimierung zur Verfügung wovon nur 12,5 % der Fläche durch den Optimierungsprozess in ihrer Nutzung umgewidmet wird. Der Wasserhaushalt der entwickelten Landnutzungsszenarien wurde mit dem Wasserhaushaltssimulationsmodell WaSiM-ETH in zehn ausgewählten Teileinzugsgebieten modelliert. Die Gebietsanpassung erfolgte dabei an den Pegeln Lauenstein und Geising mit einem multi-response Ansatz, der auch Ergebnisse einer Ganglinienseparation und Vergleiche zu einer Arbeit im benachbarten Weißeritzeinzugsgebiet berücksichtigt. Im Ergebnis zeigte die Validierung eine gelungene Gebietsanpassung des Modells WaSiM-ETH mit geringen Schwächen im Winter und bei außergewöhnlichen Extremereignissen. Insgesamt zeigt sich in allen modellierten Teileinzugsgebieten ein Rückgang des Gesamtabflusses, allerdings in Größenordnungen, die sich räumlich sehr stark unterscheiden. Berechnet wurde dabei nur der Wasserhaushalt für das Szenario „Abflussminimierung“, da sich beide Szenarien in den hydrologisch ähnlichen Teileinzugsgebieten nur wenig unterscheiden. Die statistische Auswertung der Ergebnisse erfolgte mit Spearmans Rangkorrelations¬koeffizient und zeigte: • dass mit steigender Höhenlage die Möglichkeiten der Abflussminimierung durch Landnutzungsveränderungen abnehmen. Im Indikator Höhenlage spiegeln sich dabei mehrere Parameter wider, welche die sich mit der Höhe wandelnden Klima-, Boden- und Reliefbedingungen ausdrücken. • dass mögliche Abflussminderungen mit dem Ackeranteil eines Einzugsgebietes positiv signifikant korreliert sind. Die Abflussminderungspotentiale steigen also mit steigendem Ackeranteil an. • dass die absolute Niederschlagsmenge keinen direkten Einfluss auf die Abflussminderung hat, vielmehr ist die jährliche Niederschlagsverteilung bedeutsam für die Möglichkeiten des Wasserrückhaltes in der Fläche. Als Voraussetzung für die erfolgreiche Anwendung von LNOPT im Rahmen hydrologischer Fragestellungen sind die Berücksichtigung beziehungsweise Bearbeitung folgender Punkte: • Ermittlung der hydrologischen Senkenpotentiale zu Beginn des Planungsprozesses um sich auf Gebiete mit hohem hydrologischen Senkenpotential zu konzentrieren, • Planung von Landnutzungsveränderungen hinsichtlich Nutzungstyp, Nutzungsart oder Nutzungsintensität anhand von Bewertungsverfahren, welche die hydrologischen Differenzen gut widerspiegeln, • Einbeziehung der handelnden Akteure in den Planungsprozess um die möglichst vollständige Umsetzung der geplanten Maßnahmen zu ermöglichen. Mit der vorliegenden Arbeit wird gezeigt, dass im Mittelgebirgsraum Abflussminderungspotentiale im Zuge von Landnutzungsveränderungen vorhanden sind, diese aber regional sehr stark differenziert ausgeprägt sind. Methodisch konnte demonstriert werden, dass das eingesetzte Verfahren der multikriteriellen Landnutzungsoptimierung zur Planungsunterstützung im Rahmen hydrologischer Fragestellungen genutzt werden kann, wenn die genannten Rahmenbedingungen beachtet werden. / The hydrological balance of a landscape integrates different geocomponents such as climate, soil and land use and is an object of intensive research activities. The specific characteristic of the hydrological balance of a landscape shows the result of a complex utilisation system which is caused by manifold driving forces. Due to different strategic objectives of thestakeholders, their demands are contrasting and therefore it is very difficult to coordinate these demands with respect to influencing the hydrological balance of a landscape. Changes of land use in non-settled areas have the highest potential of modifying the hydrological balance of a landscape due to the large extent of affected area. In this thesis two different methodical approaches are used to analyse the hydrological processes in the water balance of a landscape in order to investigate the effects of land use changes on the hydrological balance of a landscape. The applied methods are hydrological modelling and functional landscape assessment. Hydrological modelling quantifies the water balance of scenarios made by a much easier to realise planning method on the basis of a functional landscape assessment. Land use scenarios on the basis of a functional landscape assessment can be build through a multi-criteria optimisation process using the software LNOPT (“land use op-timisation”). By using this method, the hydrological balance of a landscape and the specific local conditions are described by the following landscape functions: runoff regulation, resistance against water erosion, biotic yield potential and physical-chemical cleaning potential of soils. On the basis of the assessment of these landscape functions, two land use scenarios were developed using the method of multi-criteria optimisation, namely, a more realistic scenario and one with the highest possible water retention potential. Even though both scenarios are different in their closeness to reality, they are both inspired by reality and not just fictitious. Due to different restrictions only 36.5 % of the entire catchment area could be used in the optimisation process. In the scenario with the highest possible water retention potential only 12.5 % of the land use was changed and in the more realistic scenario the changes were slightly smaller. The water balance simulation model WaSiM-ETH is well suited to quantify changes in the hydrological balance in the context of land-use changes at the meso-scale. The adaptations to the catchment area characteristics were done by the calibration on the gauges Lauenstein and Geising in a multi response approach considering results of a hydrograph curve separation and the results of a research in the neighbouring Weisseritz catchment. The validation shows a successful adaptation to the regional catchment area characteristics with minor shortcomings in winter and by extraordinary high precipitation events. In the whole investigated area possible changes of the hydrological balance are rather negligible due to only small land use changes. But in 10 selected subcatchments the hydrological modelling shows a decrease of discharge in the scenario with the highest possible water retention potential. The dimensions of the decrease in the discharge are regionally very different due to varying spatial characteristics. These differences get systemised through a statistical analysis using the Spearman’s Rank Correlation Coefficient. The following correlations were found: • The possibilities of a decrease in discharge through land use modification are getting smaller with an increase in altitude. The complex indicator “altitude” contains different parameters which reflect the shifting of climatic, soil and relief conditions with changing altitude. • The possibilities of a decrease in discharge are getting higher with the percentage of arable land in the subcatchments. • The amount of precipitation has no direct influence of the possible decrease in discharge in the subcatchments. The influence of the annual variation of precipitation is larger than the absolute annual amount of precipitation. For a successful application of LNOPT for the development of land use scenarios with a hydrologic context the following requirements have to be considered: • ahead of the planning process, pedological and geological potentials of the investigated area in terms of a decrease in discharge should be investigated • landscape functions which show hydrological differences in terms of land use types, the kind and the intensity of land use should be used • local steak holders should be integrated in the planning process to ensure the complete implementation of the planned measures as much as possible. In this thesis it could be shown that mountainous regions have a potential for a decrease in discharge caused by a land use change, but with substantial regional variations. The evaluation of the used methods demonstrated that the multi-criteria optimisation software LNOPT is well suited to support hydrological related planning processes if conditions mentioned above are considered.

Pollution of surface and groundwater, due to improper land management, has become a major problem worldwide. Integrated watershed modelling provides a tool for the understanding of the processes governing water and matter transport at different scales within the watershed. The Soil Water Assessment Tool (SWAT) has been successfully utilized for the combined modelling of water fluxes and quality within a large range of scales and environmental conditions across the world. For suitable assessments integrated watershed models require large data sets of measured information for both model parameterization as for model calibration and validation. Data scarcity represents a serious limitation to the use of hydrologic models for supporting decision making processes, and may lead unsupported statements, poor statistics, misrepresentations, and, ultimately, to inappropriate measures for integrated water resources management efforts. In particular, the importance of spatially distributed soil information is often overlooked. In this thesis the eco-hydrological SWAT model was been applied to assess the water balance and diffuse pollution loadings of two rivers within a rural context at the mesoscale watershed level: 1) the Western Bug River, Ukraine, 2) the Águeda River, Portugal. Both watersheds in focus serve as examples for areas where the amount and quality of the measured data hinders a strait forward hydrologic modelling assessment. The Dobrotvir watershed (Western Bug River, Ukriane) is an example of such a region. In the former Soviet Union, soil classification primarily focused on soils of agricultural importance, whereas, forested, urban, industrial, and shallow soil territories were left underrepresented in the classification systems and resulting soil maps. Similarly the forest-dominated Águeda watershed in North-Central Portugal is a second example of a region with serious soil data availability limitations. Through the use of pedotransfer functions (PTFs) and the construction of soil-landscape models the data gaps could be successfully diminished, allowing a subsequent integrated watershed modelling approach. A valuable tool for the data gap closure was the fuzzy logic Soil Land Inference Model (SoLIM) which, combined with information from several soil surveys, was used to create improved maps. In the Dobrotvir watershed the fuzzy approach was used to close the gaps of the existing soil map, while in the Águeda watershed a new soil properties map, based upon the effective soil depths of the landscape, was constructed. While the water balance simulation in both study areas was successful, a calibration parameter ensemble approach was tested for the Águeda watershed. In the common modelling practice the individual best simulation and best parameter set is considered, the tested approach involved merging individual model outputs from numerous acceptable parameter sets, tackling the problematic of parameter equifinality. This procedure was tested for both original soil map and the newly derived soil map with differentiation of soil properties. It was noticeable that a better model set-up, with a better representation of the soil spatial distribution, was reflected in tighter model output spreads and narrower parameter distances. A further challenge was the calibration of water quality parameters, namely nitrate-N in the Dobrotvir watershed and sediment loads in the Águeda watershed. The limited amount of water quality observations were handled by assessing and by process verification at the smallest modelling unit, the hydrological response unit (HRU). The ruling hydrological processes could be depicted by combining own measured data and modelling outputs. The management scenario simulations showed the anticipated response to changes in management and reflected the rational spatial variation within the watershed reasonably well. The impacts of the different intervention options were evaluated on water balance, nitrate-N export and sediment yield at the watershed, sub-watershed and, when feasible, HRU level. This thesis covers two regional case studies with particular data limitations and specific processes of water and matter fluxes. Still, data reliability is a problem across the globe. This thesis demonstrates how relevant it is to tackle shortages of spatially differentiated soil information. The considered approaches contribute toward more reliable model predictions. Furthermore, the tested methods are transferable to other regions with differing landscape and climate conditions with similar problems of data scarcity, particularly soil spatially differentiated information.

Tesis por compendio / [ES] Los Pavimentos Permeables (PP) son una técnica de los denominados Sistemas Urbanos de Drenaje Sostenible (SUDS). A diferencia de otras técnicas de este tipo, proporciona una superficie dura transitable a la vez que gestiona las aguas pluviales superficiales, siendo sus propiedades hidráulicas fundamentales para su rendimiento como SUDS. Esta tesis explora el rendimiento hidráulico de los PP, basándose en el modelo hidrológico-hidráulico de PP proporcionado en el ampliamente utilizado Storm Water Management Model (SWMM). La tesis se presenta en un formato de tres artículos. Así, tras una aproximación a la pregunta general de investigación dada en el primer capítulo introductorio, el segundo capítulo del documento analiza qué parámetros son los más influyentes y cuáles son despreciables en el modelo, proporcionando un análisis de sensibilidad general. El siguiente capítulo explora la relación entre el modelo de PP de SWMM y el modelo de número de curva (CN), ampliamente utilizado, en lo que respecta a la escorrentía deducida por ambos modelos en función de la permeabilidad del pavimento. En el cuarto capítulo se analiza la respuesta del PP en condiciones experimentales controladas y se compara con el modelo de PP dado en SWMM. Tras una discusión general de los resultados en el quinto capítulo, se ofrecen unas conclusiones generales en el último. La tesis profundiza en el conocimiento del comportamiento hidráulico de los PP para ayudar a profesionales e investigadores en su caracterización. / [CA] Els Paviments Permeables (PP) són una tècnica dels denominats Sistemes Urbans de Drenatge Sostenible (SUDS). A diferència d'altres tècniques d'aquest tipus, proporciona una superfície dura transitable alhora que gestiona les aigües pluvials superficials, sent les seues propietats hidràuliques fonamentals per al seu rendiment com SUDS. Aquesta tesi explora el rendiment hidràulic dels PP, basant-se en el model hidrològic-hidràulic de PP proporcionat en l'àmpliament utilitzat Storm Water Management Model (SWMM). La tesi es presenta en un format de tres articles. Així, després d'una aproximació a la pregunta general d'investigació donada en el primer capítol introductori, el segon capítol del document analitza quins paràmetres són els més influents i quins són menyspreables en el model, proporcionant una anàlisi de sensibilitat general. El següent capítol explora la relació entre el model de PP de SWMM i el model de número de corba (CN), àmpliament utilitzat, pel que fa a l'escolament deduït per tots dos models en funció de la variable permeabilitat del paviment. En el quart capítol s'analitza la resposta del PP en condicions experimentals controlades i es compara amb el model de PP donat en SWMM. Després d'una discussió general dels resultats en el cinqué capítol, s'ofereixen unes conclusions generals en l'últim. La tesi aprofundix en el coneixement del comportament hidràulic dels PP per a ajudar a professionals i investigadors en la seua caracterització. / [EN] Permeable Pavements (PP) are a Sustainable Urban Drainage System (SUDS) technique. Unlike other such techniques, it provides a transitable hard surface while managing surface stormwater, being its hydraulic properties fundamental for its performance as a SUDS. This dissertation explores the hydraulic performance of PPs, based on the hydrologic-hydraulic model of PP provided in the widely used Storm Water Management Model (SWMM). The dissertation is presented in a \textit{three-paper} format. Accordingly, after an approach to the general research question given in the first introductory chapter, the second chapter of the document analyses which parameters are the most influential and which are negligible in the model by providing a general sensitivity analysis. The next chapter explores the relation between the PP model from SWMM and the widely used Curve Number (CN) model regarding runoff generated by both models and examines the relationship between both approaches based on the pavement permeability variable. The fourth chapter analyses the PP response under controlled experimental conditions and compares it with the PP model given in SWMM. After a general discussion of the results in the fifth chapter, general conclusions are given in the last chapter. The dissertation deepens the understanding of the hydraulic behaviour of PPs to help practitioners and researchers with its characterisation. / Madrazo Uribeetxebarria, E. (2023). Modelling the Hydraulic Response of Permeable Pavements: a Numerical and Experimental Approach for Model Comparison and Sensitivity Analysis to Design Parameters [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/196085 / Compendio

As research has expanded on the environmental impact of stormwater on receiving ecosystems more focus is now being put on the quality issues of stormwater. Biofilters are one of many nature-based solutions that have been developed for that purpose and are also the subject of this study. In order to plan and implement biofilters, predictive models can be useful tools to forecast their performance on a given site. The aim of this study was to investigate the possibilities and limitations of modelling the treatment of stormwater in a biofilter using MIKE+. This was done by first trying to model the hydrological conditions of a biofilter from a study site in Sundsvall and thereafter coupling a water treatment model created in ECO Lab.  The results showed that there were some notable differences between the parameters affecting the hydrological flow in reality and what is currently possible to model in MIKE+. It was seen that the Soakaway node used to model biofilters needs to be complexified in order to properly model the hydrological conditions of biofilters. The main improvements required are that the flow attenuation should occur within the Soakaway node rather than before or after and that it should be based on soil properties. The retention volume also needs to be integrated in the node and a varying exfiltration rate is believed to be required to fit the varying nature of evapotranspiration.  The hydrological model was seen to have a great impact on the water treatment model and some limitations with the program and the used model were identified. Regarding ECO Lab, the program is currently unable to consider interevent processes when the biofilter is empty. These processes can however be of great importance for some contaminants. The program also assumes a time dependency whereas it has been seen that a short retention time may be sufficient to achieve good reduction efficiency. The model used is a highly lumped conceptual model with few parameters so further research aiming at the creation of correction factors for the main affecting parameters is believed to be required in order to avoid design specific calibration. Calibration should also occur over a longer time period in order to consider the variability of stormwater. / I takt med att forskningen kring dagvattens miljöpåverkan på mottagande ekosystem avancerats har hanteringen av dagvatten gått från att enbart fokusera på dess kvantitet till att även fokusera på dess kvalitet. Biofilter är en av flera naturbaserade lösningar som utvecklats för detta ändamål. För att kunna planera och implementera biofilter kan prediktiva modeller vara användbara verktyg för att förutse deras prestanda i ett tilltänkt område. Syftet med denna studie var att undersöka möjligheterna att modellera dagvattenreningen i ett biofilter med hjälp av MIKE+. Detta gjordes genom att först försöka modellera de hydrologiska förhållandena i ett biofilter från ett studieområde i Sundsvall och därefter koppla en vattenreningsmodell skapad i ECO Lab.  Resultatet visade att det finns några märkbara skillnader mellan de parametrar som påverkar det hydrologiska flödet i biofilter i verkligheten och vad som för närvarande är möjligt att modellera i MIKE+. Det visades att Soakaway-noden som används för att modellera biofilter behöver utvecklas för att kunna modellera de hydrologiska förhållandena på ett korrekt sätt. De främsta förbättringar som krävs är att flödesdämpningen bör ske inom Soakaway-noden snarare än innan eller efter och att denna flödesdämpning bör baseras på filtrets markegenskaper. Retentionsvolymen behöver dessutom integreras i noden och en varierande exfiltrationshastighet tros krävas för att kunna ta hänsyn till hur evapotranspiration varierar över tid.  Den hydrologiska modellen sågs ha stor inverkan på vattenreningsmodellen och vissa begränsningar kunde visas hos programmet och den använda modellen. När det gäller ECO Lab kan programmet för närvarande inte ta hänsyn till processer mellan event när biofiltret är tomt. Dessa processer kan dock ha stor betydelse för vissa föroreningar. Programmet förutsätter också ett tidsberoende trots att forskning visat att en kort uppehållstid kan vara tillräcklig för att uppnå god reningseffekt. Modellen som används är en mycket enkel konceptuell modell med få parametrar så vidare forskning rekommenderas med syfte att skapa korrektionsfaktorer för att bättre ta hänsyn till de viktigaste reningsfaktorer och undvika platsspecifik kalibrering. Kalibreringen bör även ske under en längre tidsperiod för att ta hänsyn till variationerna i dagvatten.

Floods are one of the most devastating types of worldwide disasters in terms of human, economic, and social losses. If authoritative data is scarce, or unavailable for some periods, other sources of information are required to improve streamflow estimation and early flood warnings. Georeferenced social media messages are increasingly being regarded as an alternative source of information for coping with flood risks. However, existing studies have mostly concentrated on the links between geo-social media activity and flooded areas. This thesis aims to show a novel methodology that shows a way to close the research gap regarding the use of social networks as a proxy for precipitation-runoff and flood forecast estimates. To address this, it is proposed to use a transformation function that creates a proxy variable for rainfall by analysing messages from geo-social media and precipitation measurements from authoritative sources, which are then incorporated into a hydrological model for the flow estimation. Then the proxy and authoritative rainfall data are merged to be used in a data assimilation scheme using the Ensemble Kalman Filter (EnKF). It is found that the combined use of authoritative rainfall values with the social media proxy variable as input to the Probability Distributed Model (PDM), improves flow simulations for flood monitoring. In addition, it is found that when these models are made under a scheme of fusion-assimilation of data, the results improve even more, becoming a tool that can help in the monitoring of \"ungauged\" or \"poorly gauged\" catchments. The main contribution of this thesis is the creation of a completely original source of rain monitoring, which had not been explored in the literature in a quantitative way. It also shows how the joint use of this source and data assimilation methodologies aid to detect flood events. / As inundações são um dos tipos mais devastadores de desastres em todo o mundo em termos de perdas humanas, econômicas e sociais. Se os dados oficiais forem escassos ou indisponíveis por alguns períodos, outras fontes de informação são necessárias para melhorar a estimativa de vazões e antecipar avisos de inundação. Esta tese tem como objetivo mostrar uma metodologia que mostra uma maneira de fechar a lacuna de pesquisa em relação ao uso de redes sociais como uma proxy para as estimativas de precipitação e escoamento. Para resolver isso, propõe-se usar uma função de transformação que cria uma variável proxy para a precipitação, analisando mensagens de medições geo-sociais e precipitação de fontes oficiais, que são incorporadas em um modelo hidrológico para a estimativa de fluxo. Em seguida, os dados de proxy e precipitação oficial são fusionados para serem usados em um esquema de assimilação de dados usando o Ensemble Kalman Filter (EnKF). Descobriu-se que o uso combinado de valores oficiais de precipitação com a variável proxy das mídias sociais como entrada para o modelo distribuído de probabilidade (Probability Distributed Model - PDM) melhora as simulações de fluxo para o monitoramento de inundações. A principal contribuição desta tese é a criação de uma fonte completamente original de monitoramento de chuva, que não havia sido explorada na literatura de forma quantitativa.

Die Untersuchung von Klimaszenarien ergab, dass die Grundwasserneubildung in Nordostdeutschland abnehmen könnte. Um Süßgewässer zu erhalten müssen neue Strategien entwickelt werden. Im Gebiet des Lietzengrabens wird Klarwasser eingeleitet, um Feuchtgebiete und Seen zu erhalten. Diese Strategie wurde durch eine Szenarioanalyse erarbeitet, die sich auf das hydrologische iterative Modell ArcEGMO-ASM stützte. In dieser Arbeit wurde das voll integrierte Modell HydroGeoSphere genutzt, um den Fluss von Wasser an der Oberfläche und im Untergrund zu simulieren. Basierend auf dieser Simulation wurden Fließpfade und Aufenthaltszeiten abgeschätzt. Die Ergebnisse beider Modelle wurden analysiert und verglichen. Mit beiden Modellen war es möglich, die Abfluss- und Grundwasserdynamiken im Einzugsgebiet zu reproduzieren. Bei der Anwendung von HydroGeoSphere fehlten Möglichkeiten zur Berücksichtigung von z.B. Schneefall und Wehren, welche in ArcEGMO-ASM vorhanden sind. Die Kalibrierung des Modells lieferte Parameterwerte, die eine Reproduktion der Dynamiken erlaubten. Allerdings könnte HydroGeoSphere nur eingeschränkt nutzbar sein, da die Werte teils unrealistisch waren. HydroGeoSphere ermöglichte aber die Abschätzung von unterirdischen Fließpfaden und Aufenthaltszeiten. Weiter wurde der Austritt von Grundwasser in einen Bachabschnitt durch Messungen bestimmt und mit Simulationsergebnissen verglichen. Keines der Modelle war geeignet, die räumlichen Muster auf dieser Skala zu reproduzieren. Die simulierten Exfiltrationsraten wichen von den beobachteten ab. Der Vergleich von ArcEGMO-ASM und HydroGeoSphere zeigte die Vorteile und Grenzen der Modelle auf. Der Einsatz von HydroGeoSphere bei Untersuchungen von Bewirtschaftungsstrategien macht sich noch nicht bezahlt, vergleicht man den Aufwand mit den Vorteilen. Da HydroGeoSphere weiterentwickelt wird und die Rechenkapazitäten zunehmen, könnte das Modell in der nahen Zukunft in der Praxis nutzbar sein. / Analysis of climatic scenarios for North-East Germany showed that groundwater recharge could decline. In order to sustain freshwaters, new strategies must be developed. At the Lietzengraben catchment treated wastewater is discharged to sustain wetlands and lakes in the catchment. This management strategy was developed previously by scenario analysis, performed by the hydrological iterative model ArcEGMO-ASM. In this work, the fully integrated model HydroGeoSphere was used to simulate the surface and subsurface water flow in the catchment. Based on the simulation results, flow paths and residence times were estimated. The results of the simulations by both models were investigated and compared. It was possible to reproduce the catchment dynamics regarding discharge and groundwater heads reasonably well with both models. The application of HydroGeoSphere was limited due to the inability of the model to represent features like snowfall and weirs, which are represented in ArcEGMO-ASM. The calibrated parameter values enabled the model to reproduce the catchment dynamics reasonably well. HydroGeoSphere may be limited in its use since the obtained values are partially unrealistic. HydroGeoSphere allowed the approximation of subsurface flow paths and residence times. The exfiltration of groundwater to a stream reach was estimated by measurements and compared to simulation results. Both models were not able to reproduce the spatial patterns on a sub-reach scale and the calculated exfiltration rates did not match the observed rates. The comparison of ArcEGMO-ASM and HydroGeoSphere showed the advantages and limitations of both models. Comparing the overall additional effort to the benefits, however, the application of HydroGeoSphere to investigations regarding management strategies or scenario analyses may not pay off. Since HydroGeoSphere is under steady development and computational resources improve, the use of HydroGeoSphere may be applicable in the near future.