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Replication Data for: "Impact of climate change on recharge and vadose-phreatic storage dynamics of a Mediterranean karst aquifer: Quantitative approach for the management of a complex groundwater resource"
No full textThis repository provides the resources related to the Ph.D. thesis titled "Impact of climate change on recharge and vadose-phreatic storage dynamics of a Mediterranean karst aquifer: Quantitative approach for the management of a complex groundwater resource"
Grundwasseranreicherung mit entsalztem Meerwasser in Festgesteinsgrundwasserleitern
No full textIn dieser Studie wird die Eignung von Festgesteinsaquiferen im östlichen mediterranen Raum zur Nutzung als Speicher von entsalztem Meerwasser untersucht. Hierzu wurden zunächst technische Kriterien als Indikatoren zur Eignung definiert und auf deren Basis eine Voruntersuchung durchgeführt, um anschließend für ausgewählte Aquifere mit numerischen Modellen Bewirtschaftungsmaßzahlen zu quantifizieren. Es zeigt sich, dass eine Reihe von Aquiferen als Speichermedium genutzt werden könnten, dies zum Teil sogar entgegen naheliegender Erwartungen
Variably saturated dual-permeability flow modeling to assess distributed infiltration and vadose storage dynamics of a karst aquifer – The Western Mountain Aquifer in Israel and the West Bank
No full textAvailable methods to quantify the recharge of karst aquifers usually rely on spatially and temporally aggregated precipitation measurements and simplified recharge models, employing transfer functions to account for the delay in infiltration and the distribution in time and space. They generally neglect the non-linear nature of infiltration dynamics through the vadose zone, characterized by dual flow behavior with slow diffuse and rapid focused recharge components. Here, we present a methodology that accounts for the physics of flow by employing a variably saturated dual-permeability flow model to simulate diffuse and preferential infiltration in a large-scale carbonate aquifer. The Western Mountain Aquifer (WMA) in Israel and the West Bank was selected as a suitable groundwater basin because of the large thickness of the vadose zone, extending over several hundred-meters, the availability of long-term data as well as the catchment size, stretching across a catchment area of circa 9000km2. Together, these characteristics allow the identification and quantification of the spatio-temporal distribution of the infiltration/recharge component, assessed at the level of the groundwater table. The presented methodology allows for improved water resources planning and generalization of the results, i.e., the robustness of large-scale model results with respect to local hydraulic parameter variations and data uncertainty. Semi-arid climate regions with a highly pronounced seasonality of precipitation and intense short-duration rainfalls, such as the Mediterranean region, represent a prime study location because of the clear and pronounced recharge input signals that are not superimposed by summer rainstorms. We simulate the complex dynamics of the dual-domain infiltration and partitioning of the precipitation input signal by employing HydroGeoSphere (HGS) for transient variably saturated water flow. Flow in the limestone rock matrix and high porosity system (i.e., conduits and fractures) is modeled by overlapping individual continua based on the bulk-effective Richards’ equation with van Genuchten (VG) parameters
Impact of climate change on recharge and vadose-phreatic storage dynamics of a Mediterranean karst aquifer: Quantitative approach for the management of a complex groundwater resource
No full textThe Mediterranean basin will be severely affected by global warming and decreased average rainfall and is often portrayed as the most prominent climate change hotspot. At the same time, the Mediterranean basin is endowed with many karst aquifers that are particularly susceptible to droughts due to their hydrogeological characteristics. This thesis addresses the impact of climate change and future groundwater management scenarios on the recharge and storage dynamics of Mediterranean karst water resources using the example of the Western Mountain Aquifer (WMA) in Israel and the West Bank. The main objectives of this thesis are (1) to demonstrate the applicability of variably saturated dual-permeability flow modeling at the catchment scale for the prediction of vadose-phreatic groundwater storage dynamics in karst, (2) the assessment of climate change and groundwater consumption effects and lastly (3) the development of management strategies to mitigate the effects of prolonged droughts. This study employs the finite element, distributed, dual-continuum flow simulator HydroGeoSphere on a high-performance-computing platform. Flow in the variably saturated fractured-porous subsurface is simulated using a dual-permeability approach based on Richards’ equation, assuming that homogenization of microscopic fluid dynamics is valid for both flow domains. We employ the van Genuchten material model to predict the partially saturated permeability but truncate the saturation-permeability relation under dry conditions to maintain a minimum permeability, accounting for gravity-dominated infiltration. This way, the duality of karstic flow, with rapid flow through conduits and slow flow through the rock matrix, can be modeled in both the vadose and phreatic zone. The simulation results highlight the relevance of thick vadose zones in karst aquifers. Vadose storage comprises circa ~45% of the overall dynamic storage in the WMA and has a significant smoothing influence on the temporal characteristics of recharge at the groundwater table of the WMA. Highly variable diurnal precipitation is dampened, and long-term seasonal fluxes become more prominent further from the surface. Subsequently, this thesis employs the presented model to forecast groundwater recharge and storage dynamics under climate change, where two coherent dynamically downscaled high-resolution regional climate projections (daily, 3km, and 8km resolution) until the year 2070 serve as input to the recharge assessment. The model predictions indicate that climate change has a mitigated impact on average recharge because of pathways of preferential infiltration in karst aquifers and the increased intensity of individual rainfall events. However, despite the attenuated decrease of long-term groundwater recharge, the extended meteorological drought periods over several years pose a significant challenge to the consistent freshwater supply from groundwater resources, requiring more resilient management options that generate surpluses in times of increased precipitation input and utilize the aquifer storage during droughts. Lastly, the developed model is employed to assess the storage potential of the WMA for managed aquifer recharge.2023-04-1
Bewertung der Anwendbarkeit von Single-Well Push-Pull Tracer-tests zur Bestimmung von Porosität und Dispersivität bei geringen hydraulischen Gradienten und in Brunnen mit großem Durchmesser
Full text linkDie Bachelorarbeit bezieht sich auf die Rohdaten, die bei DAKS hochgeladen sin
In-Situ Untersuchung des Sorptionsverhaltens von Natrium mittels eines Single-Well Push-Pull Tracerversuchs
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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