Evaluation of empirical approaches to estimate the variability of erosive inputs in river catchments

Die Dissertation erforscht die Unsicherheit, Sensitivität und Grenzen großskaliger Erosionsmodelle. Die Modellierung basiert auf der allgemeinen Bodenabtragsgleichung (ABAG), Sedimenteintragsverhältnissen (SDR) und europäischen Daten. Für mehrere Regionen Europas wird die Bedeutung der Unsicherheit topographischer Modellparameter, ABAG-Faktoren und kritischer Schwebstofffrachten für die Anwendbarkeit empirischer Modelle zur Beschreibung von Sedimentfrachten und SDR von Flusseinzugsgebieten untersucht. Der Vergleich alternativer Modellparameter sowie Kalibrierungs- und Validierungsdaten zeigt, dass schon grundlegende Modellentscheidungen mit großen Unsicherheiten behaftet sind. Zur Vermeidung falscher Modellvorhersagen sind kalibrierte Modelle genau zu dokumentieren. Auch wenn die geschickte Wahl nicht-topographischer Algorithmen die Modellgüte regionaler Anwendungen verbessern kann, so gibt es nicht die generell beste Lösung. Die Ergebnisse zeigen auch, dass SDR-Modelle stets mit Sedimentfrachten und SDR kalibriert und evaluiert werden sollten. Mit diesem Ansatz werden eine neue europäische Bodenabtragskarte und ein verbessertes SDR-Modell für Einzugsgebiete nördlich der Alpen und in Südosteuropa abgeleitet. In anderen Regionen Europas ist das SDR-Modell bedingt nutzbar. Die Studien zur jährlichen Variabilität der Bodenerosion zeigen, dass jahreszeitlich gewichtete Niederschlagsdaten geeigneter als ungewichtete sind. Trotz zufriedenstellender Modellergebnisse überwinden weder sorgfältige Algorithmenwahl noch Modellverbesserungen die Grenzen europaweiter SDR-Modelle. Diese bestehen aus der Diskrepanz zwischen modellierten Bodenabtrags- und maßgeblich zur beobachteten bzw. kritischen Sedimentfracht beitragenden Prozessen sowie der außergewöhnlich hohen Sedimentmobilisierung durch Hochwässer. Die Integration von nicht von der ABAG beschriebenen Prozessen und von Starkregentagen sowie die Disaggregation kritischer Frachten sollte daher weiter erforscht werden.This dissertation thesis addresses the uncertainty, sensitivity and limitations of large-scale erosion models. The modelling framework consists of the universal soil loss equation (USLE), sediment delivery ratios (SDR) and European data. For several European regions, the relevance of the uncertainty in topographic model parameters, USLE factors and critical yields of suspended solids for the applicability of empirical models to predict sediment yields and SDR of river catchments is systematically evaluated. The comparison of alternative model parameters as well as calibration and validation data shows that even basic modelling decisions are associated with great uncertainties. Consequently, calibrated models have to be well-documented to avoid misapplication. Although careful choices of non-topographic algorithms can also be helpful to improve the model quality in regional applications, there is no definitive universal solution. The results also show that SDR models should always be calibrated and evaluated against sediment yields and SDR. With this approach, a new European soil loss map and an improved SDR model for river catchments north of the Alps and in Southeast Europe are derived. For other parts of Europe, the SDR model is of limited use. The studies on the annual variability of soil erosion reveal that seasonally weighted rainfall data is more appropriate than unweighted data. Despite satisfactory model results, neither the careful algorithm choice nor model improvements overcome the limitations of pan-European SDR models. These limitations are related to the mismatch of modelled soil loss processes and the relevant processes contributing to the observed or critical sediment load as well as the extraordinary sediment mobilisation during floods. Therefore, further research on integrating non-USLE processes and heavy-rainfall data as well as on disaggregating critical yields is needed

Comparison of GPR results with UAV photogrammetry at a Roman villa rustica in Noricum (southern Bavaria)

Ground penetrating radar was used for mapping the layout of a Roman villa rustica. Adjacent rescue excavation results were mapped by UAV photogrammetry. The combination with a photogrammetric model enables a ground truthing of GPR result

Reconstructing a Romanesque church based on GPR results

We present an integrated prospection of the remains a medieval monastery in Lower Franconia (Germany) built over with a Renaissance castle. The geophysical data is combined with a photogrammetric model of the Renaissance castle. Based on the geophysical data, a virtual reconstruction of the medieval church was achieved

Einfluss der Schweißparameter und Polaritätsmodulationen auf den Werkstoffübergang sowie Zu- und Abbrandverhalten von Legierungselementen beim Unterpulverschweißen

Gegenstand der Untersuchungen sind Kavernenvorgänge und Werkstofftransfer beim Unterpulverschweißen unter besonderer Berücksichtigung des Zu- und Abbrandes von Legierungselementen und Eisenbegleitern. Dabei wurde der Einfluss von Schweißparametervariationen, insbesondere die Wirkung durch Verschiebung des Zeitanteils der Wechselstromhalbwellen, untersucht. Die Untersuchungen wurden an Massiv- und Fülldrähten mit unterschiedlichen Legierungskonzepten durchgeführt. Die Übertragbarkeit der Erkenntnisse auf UP-Mehrdrahtschweißungen wurde durch begleitende chemische Untersuchungen dargestellt

Good Intentions: Adaptive Parameter Management via Intent Signaling

Parameter management is essential for distributed training of large machine learning (ML) tasks. Some ML tasks are hard to distribute because common approaches to parameter management can be highly inefficient. Advanced parameter management approaches -- such as selective replication or dynamic parameter allocation -- can improve efficiency, but to do so, they typically need to be integrated manually into each task's implementation and they require expensive upfront experimentation to tune correctly. In this work, we explore whether these two problems can be avoided. We first propose a novel intent signaling mechanism that integrates naturally into existing ML stacks and provides the parameter manager with crucial information about parameter accesses. We then describe AdaPM, a fully adaptive, zero-tuning parameter manager based on this mechanism. In contrast to prior systems, this approach separates providing information (simple, done by the task) from exploiting it effectively (hard, done automatically by AdaPM). In our experimental evaluation, AdaPM matched or outperformed state-of-the-art parameter managers out of the box, suggesting that automatic parameter management is possible

Modelling nutrient pollution in the Danube River Basin: a comparative study of SWAT, MONERIS and GREEN models

The Water Framework Directive requires the development and implementation of river basin management plans for improving the ecological status of freshwater bodies throughout Europe. The scientific community supports this process by developing decision-support tools for identifying the principal sources of water pollution. Models, however, are imperfect representations of the real world, and are conditioned by structural uncertainty, implicit in the description of biophysical processes, and data uncertainty, as well as in the various restrictions of the environmental data the models were developed. Hence, decision makers must plan management actions on the basis of the best available, however still incomplete, knowledge. The comparison of independent assessments may offer insights that are useful for decision-making, e.g. for identifying knowledge gaps, identifying data uncertainties, consolidating investigation results, and increasing stakeholders’ acceptance. The Danube River is the second largest and most international river of Europe. Its basin covers approximately 803,000 km2 of Central and South-Eastern Europe and is shared by 19 countries. Within the context of fostering scientific collaboration in the Danube region and under the auspices of the International Commission for the Danube River Protection (ICPDR), three independent model (SWAT, MONERIS and GREEN) were compared with the objective of reaching a shared appraisal of nutrient pressures and drivers in the Danube Basin. Annual water discharge (Flow, m3/s) as well as annual loads of total nitrogen (TN, ton/y) and total phosphorus (TP, ton/y) were compared at the outlet of 18 ICPDR regions for the decade 2000-2009. For each region, mean annual values, correlation, standard deviation, and root mean square error of model simulations were analysed. Good water discharge simulations across the basin confirmed that hydrology was correctly represented in all models. The nutrients comparison revealed for some assessment regions the need for a spatially and temporarily intensified monitoring especially for TN. Concerning TP, SWAT and MONERIS had comparable long mean annual TP loads, but differed for amplitude and phases; while GREEN generally overestimated TP loads. Despite differences in model approaches and considered input data, the three assessments were coherent, and all three models may be confidently used for river basin management of the region.JRC.H.1-Water Resource

Conceptualizing Environmental Citizenship for 21st Century Education

This open access book is about the development of a common understanding of environmental citizenship. It conceptualizes and frames environmental citizenship taking an educational perspective. Organized in four complementary parts, the book first explains the political, economic and societal dimensions of the concept. Next, it examines environmental citizenship as a psychological concept with a specific focus on knowledge, values, beliefs and attitudes. It then explores environmental citizenship within the context of environmental education and education for sustainability. It elaborates responsible environmental behaviour, youth activism and education for sustainability through the lens of environmental citizenship. Finally, it discusses the concept within the context of different educational levels, such as primary and secondary education in formal and non-formal settings. Environmental citizenship is a key factor in sustainability, green and cycle economy, and low-carbon society, and an important aspect in addressing global environmental problems. It has been an influential concept in many different arenas such as economy, policy, philosophy, and organizational marketing. In the field of education, the concept could be better exploited and established, however. Education and, especially, environmental discourses in science education have a great deal to contribute to the adoption and promotion of environmental citizenship.info:eu-repo/semantics/publishedVersio