Search

Zum Ende des Jahres 2018 wurde in Deutschland der Steinkohlenbergbau eingestellt. Damit beginnt auch in den bis zuletzt aktiven Revieren die Phase des Nachbergbaus inklusive einer dauerhaften Wasserhaltung. Diese beinhaltet typischerweise eine teilweise Grubenflutung und die Ableitung von Grubenwasser in nahegelegene Vorfluter. Im Blickpunkt der öffentlichen und wissenschaftlichen Diskussion stehen bergbauliche Schadstoffquellen und deren Risiken für die oberflächennahen Trinkwasserressourcen. Es existieren eine Reihe Kriterien und Kontrollmechanismen, um potenziellen Schadstoffaustrag zu erkennen und zu verhindern. Dazu zählen moderne Monitoringprogramme und Modellanwendungen, welche bestehende Schadstoffprognosen verbessern können. Daneben ist auch eine rechtlich und fachlich begründete Bewertung von Gefahrenszenarios eine entscheidende Größe für nachhaltiges Risikomanagement. Der Grubenwasseranstieg eröffnet jedoch auch Chancen, ehemalige Bergwerke für energetische Nutzungen umzurüsten. Bereits heute werden Heizkraftwerke mit Grubenwasser betrieben und es besteht großes Ausbaupotenzial. Dieser Beitrag diskutiert die Chancen und Risiken von Grubenflutungen in Deutschland und gibt einen Ausblick, welche Entwicklungen und Herausforderungen in Zukunft zu erwarten sind., Universität Greifswald (1032), Groundwater in former German coal mining areas—a scientific perspective on mine floodings

Illustrationen

GIS-based multicriteria evaluation (MCE) provides a framework for analysing complex decision problems by quantifying variables of interest to score potential locations according to their suitability. In the context of earthquake preparedness and post-disaster response, MCE has relied mainly on uninformed or non-expert stakeholders to identify high-risk zones, prioritise areas for response, or highlight vulnerable populations. In this study, we compare uninformed, informed non-expert, and expert stakeholders’ responses in MCE modelling for earthquake response planning in Vancouver, Canada. Using medium- to low-complexity MCE models, we highlight similarities and differences in the importance of infrastructural and socioeconomic variables, emergency services, and liquefaction potential between a non-weighted MCE, a medium-complexity informed non-expert MCE, and a low-complexity MCE informed by 35 local earthquake planning and response experts from governmental and non-governmental organisations. Differences in the observed results underscore the importance of accessible, expert-informed approaches for prioritising locations for earthquake response planning and for the efficient and geographically precise allocation of resources., Friedrich-Alexander-Universität Erlangen-Nürnberg (1041)

The Namibian Mesozoic successions may be remnant of a high dynamic sedimentary system that is characterized by multiple stages of sediment accumulation and erosion with contemporaneous homogenization starting with the deposition of the Permo-Carboniferous Dwyka Group strata and continues at least until the Lower Cretaceous. The Lower Cretaceous sedimentary system is interpreted to have involved at least an area covering the whole SW Gondwana, documenting the sedimentary history during the evolution from an ice house environment to an arid desert. To test the sediment homogenization hypothesis, we applied a combination of isotopic and morphometric data on detrital zircon grains, as well as whole-rock geochemical data of selected Mesozoic sandstones from Namibia. As a base for the interpretation of the detrital zircon age data we compiled a zircon age dataset with c. 44,000 analyses for the southern African region. All samples reveal a major detrital pan-African zircon age peak of c. 0.5–0.7 Ga sourced from the pan-African magmatic events occurring around the Kalahari Craton margin. The lowermost Triassic is characterized by the occurrence of additional Mesoproterozoic and Paleoproterozoic age peaks of c. 1.0–1.2 Ga and 1.8–2.0 Ga with a majority of zircon grains showing angular shapes. The protosource of these grains is interpreted to possibly be the Namaqua Metamorphic Complex and other Paleoproterozoic structural units deformed in course of the Namaqua orogeny. In contrast, other samples show a prominent Permo-Triassic age peak and completely rounded zircon grains, putatively derived from within the Gondwanides volcanic arc. The disparity in the zircon age pattern may point towards a change in provenance and also a change in the whole system of zircon recycling during the Mesozoic southern Gondwana. The Lower Triassic Neu Loore fm. are constrained to more local bedrock sources and short zircon transport distance. In contrast, zircon grains of the Middle Triassic Omingonde, the Jurassic Etjo und the Cretaceous Twyfelfontein formations are an expression for a major recycling and sediment homogenization system. The system was facilitated by an interplay between fluvial and eolian sedimentary transport systems.

Ill., graph. Darst., Kt.

Ill., graph. Darst., Kt.

Ill., graph. Darst., Kt.

graph. Darst.

Ill., graph. Darst., Kt.

Ill., graph. Darst

ill., graphs, maps

This paper is a contribution to the special issue on Advances in Convection-Permitting Climate Modeling, consisting of papers that focus on the evaluation, climate change assessment, and feedback processes in kilometer-scale simulations and observations., A recently launched project under the auspices of the World Climate Research Program’s (WCRP) Coordinated Regional Downscaling Experiments Flagship Pilot Studies program (CORDEX-FPS) is presented. This initiative aims to build first-of-its-kind ensemble climate experiments of convection permitting models to investigate present and future convective processes and related extremes over Europe and the Mediterranean. In this manuscript the rationale, scientific aims and approaches are presented along with some preliminary results from the testing phase of the project. Three test cases were selected in order to obtain a first look at the ensemble performance. The test cases covered a summertime extreme precipitation event over Austria, a fall Foehn event over the Swiss Alps and an intensively documented fall event along the Mediterranean coast. The test cases were run in both “weather-like” (WL, initialized just before the event in question) and “climate” (CM, initialized 1 month before the event) modes. Ensembles of 18–21 members, representing six different modeling systems with different physics and modelling chain options, was generated for the test cases (27 modeling teams have committed to perform the longer climate simulations). Results indicate that, when run in WL mode, the ensemble captures all three events quite well with ensemble correlation skill scores of 0.67, 0.82 and 0.91. They suggest that the more the event is driven by large-scale conditions, the closer the agreement between the ensemble members. Even in climate mode the large-scale driven events over the Swiss Alps and the Mediterranean coasts are still captured (ensemble correlation skill scores of 0.90 and 0.62, respectively), but the inter-model spread increases as expected. In the case over Mediterranean the effects of local-scale interactions between flow and orography and land–ocean contrasts are readily apparent. However, there is a much larger, though not surprising, increase in the spread for the Austrian event, which was weakly forced by the large-scale flow. Though the ensemble correlation skill score is still quite high (0.80). The preliminary results illustrate both the promise and the challenges that convection permitting modeling faces and make a strong argument for an ensemble-based approach to investigating high impact convective processes., IG and LS have been supported by the Croatian Science Foundation (HrZZ) project CARE (no. 2831). JF acknowledges support by the Spanish R + D programme through MINECO/FEDER co-funded project INSIGNIA (CGL2016-79210-R). AL-G is supported by the Spanish government though grant BES-2016-078158 and MINECO/FEDER co-funded project MULTI-SDM (CGL2015-66583-R). JM and KW-S gratefully acknowledge the support by the German Science Foundation (DFG) through project FOR 1695. DM, MP, and HT gratefully acknowledge the support received via the Austrian Science Fund (FWF) project NHCM-2 (no. P24758-N29) and the projects HighEnd:Extremes and EASICLIM, funded by the Austrian Climate Research Programme (ACRP) of the Klima- und Energiefonds (nos. KR13AC6K10981 and KR16AC0K13160, respectively). SS and TL acknowledge the support of NOTUR project no. NN9280K and the Research Council of Norway and its basic institute support of their strategic project on Climate Services. RMC and PMMS gratefully acknowledge the support of the SOLAR project (PTDC/GEOMET/7078/2014) financed by the Portuguese Foundation for Science and Technology. EJ Kendon gratefully acknowledges funding from the Joint Department of Energy and Climate Change (DECC) and Department for Environment Food and Rural Affairs (Defra) Met Office Hadley Centre Climate Programme (GA01101). S. Khodayar research is supported by the Bundesministerium für Bildung und Forschung (BMBF; German Federal Ministry of Education and Research). Support of Ministry of Education, Youth and Sports of the Czech Republic for funding the participation in Euro-CORDEX activities via the scheme INTER-TRANSFER under the Grant no. LTT17007. Funding from the Research Council of Norway through the SUPER (Grant no. 250573) and HYPRE (Grant no. 243942) projects.

International audience; Madagascar houses one of the Earth’s biologically richest, but also one of most endangered, terrestrial ecoregions. Although it is obvious that humans substantially altered the natural ecosystems during the past decades, the timing of arrival of early inhabitants on Madagascar as well as their environmental impact is still intensively debated. This research aims to study the beginning of early human impact on Malagasy natural ecosystems, specifically on Nosy Be island (NW Madagascar) by targeting the sedimentary archive of Lake Amparihibe, an ancient volcanic crater. Based on pollen, fungal spore, other non-pollen palynomorph, charcoal particle and diatom analyses combined with high-resolution sediment-physical and (in)organic geochemical data, paleoenvironmental dynamics during the past three millennia were reconstructed. Results indicate a major environmental change at ca. 1300 cal BP characterized by an abrupt development of grass (C4) dominated and fire disturbed landscape showing the alteration of natural rain forest. Further, increased soil erodibility is suggested by distinct increase in sediment accumulation rates, a strong pulse of nutrient input, higher water turbidity and contemporaneous increase in spores of mycorrhizal fungi. These parameters are interpreted to show a strong early anthropogenic transformation of the landscape from rain forest to open grassland. After ca. 1000 cal BP, fires remain frequent and vegetation is dominated by forest/grassland mosaic. While natural vegetation should be dominated by rain forest on Nosy Be, these last results indicate that human continuously impacted the landscapes surrounding the lake. At a local scale, our data support the “subsistence shift hypothesis” which proposed that population expansion with development of herding/farming altered the natural ecosystems. However, a precise regional synthesis is challenging, since high-resolution multi-proxy records from continuous sedimentary archives as well as records located further north and in the hinterland are still scarce in Madagascar. The lack of such regional synthesis also prevents precise comparison between different regions in Madagascar to detect potential (dis)similarities in climate dynamics, ecosystem responses and anthropogenic influences at the island’s scale during the (late) Holocene.

International audience; This title offers a dynamic understanding of tourism, usually defined in terms of clearly circumscribed places and temporalities, to grasp its changing spatial patterns.The first part looks at the "befores" – everyday places such as daily markets, flea markets, urban neighbourhoods, that have captured the tourists’ interest and have progressively experienced new development in their ordinary patterns. The second part investigates the "afters" – former tourist spaces moving beyond the tourism sphere and becoming places of everyday life, study, or work. Chapters explore what this means for local societies and examine this contemporary phenomenon of former tourist attractions becoming ordinary and everyday, and of ordinary places beginning to take on a tourist dimension. The hybridisation of tourist practices and ordinary practices is also explored through a range of international case studies and examples written by highly regarded and interdisciplinary academics.This edited volume will be of great interest to upper-level students, academics, and researchers in tourism, urban studies, and land use planning.

Glaciers in the dry Chilean Andes provide important ecological services, yet their mass balance response to past and ongoing climate change has been little studied. This study examines the recent (2002-2015), historical (1955-2005), and past (5000 m), using a combination of glaciological, geodetic, and ice core observations. Mass balance has been predominantly negative since 2002. Analysis of mass balance and meteorological data since 2002 suggests that mass balance is currently mostly sensitive to precipitation variations, while low temperatures, aridity and high solar radiation and wind speeds cause large sublimation losses and limited melting. Mass balance reconstructed by geodetic methods shows that Guanaco Glacier has been losing mass since at least 1955, and that mass loss has increased over time until present. An ice core recovered from the deepest part of the glacier in 2008 revealed that the glacier is cold-based with a -5.5 degrees C basal temperature and a warm reversal of the temperature profile above 60-m depth attributed to the recent atmospheric warming trend. Detailed stratigraphic and stable isotope analyses of the upper 20 m of the core revealed seasonal cycles in the delta O-18 and delta H-2 records with periods varying between 0.5 and 3 m. w.e. a(-1). Deuterium excess values larger than 10 parts per thousand suggest limited post-depositional sublimation, while the presence of numerous refrozen ice layers indicate significant summer melt. Tritium concentration in the upper 20 m of the core was very low, while Pb-210 was undetected, indicating that the glacier surface in 2008 was at least 100 years old. Taken together, these results suggest that Guanaco Glacier formed under drastically different climate conditions than today, with humid conditions causing high accumulation rates, reduced sublimation and increased melting. Reconstruction of mass balance based on correlations with precipitation and streamflow records show periods of sustained mass gain in the early 20th century and the 1980s, separated by periods of mass loss. The southern migration of the South Pacific Subtropical High over the course of the 20th and 21st centuries is proposed as the main mechanism explaining the progressive precipitation starvation of glaciers in this area.

International audience; This paper presents continuous, high resolution fossil pollen and microcharcoal records from Bo Langvlei, a lake in the Wilderness Embayment on South Africa’s southern Cape coast. Spanning the past ~1300 years and encompassing the Medieval Climate Anomaly (MCA; c. AD 950–1250) and the Little Ice Age (LIA; c. AD 1300–1850), these records provide a rare southern African perspective on past temperature, moisture and vegetation change during these much debated periods of the recent geological past. Considered together with other records from the Wilderness Embayment, we conclude that conditions in the region during the MCA chronozone were – in the context of the last 1300 years – likely relatively dry (reduced levels of Afrotemperate forest pollen) and perhaps slightly cooler (increased percentages of Stoebe-type pollen) than present. The most significant phase of forest expansion, and more humid conditions, occurred during the transition between the MCA and the most prominent cooling phase of the LIA. The LIA is clearly identified at this locality as a period of cool, dry conditions between c. AD 1600 and 1850. The mechanisms driving the changes observed in the Bo Langvlei pollen record appear to be generally linked to changes in temperature, and changes in the influence of tropical circulation systems. During warmer periods, moisture availability was higher at Bo Langvlei, and rainfall was perhaps less seasonal. During colder periods, precipitation resulting from tropical disturbances was more restricted, resulting in drier conditions. While increased precipitation has been reported during the LIA from Verlorenvlei in the Western Cape as a result of an equatorward displacement of the westerly storm-track at this time, the opposing response at Bo Langvlei suggests that any increased influence of westerlies was insufficient to compensate for the concurrent reduction in tropical/local rainfall in the region.

International audience; The objective of the study is to propose a relational approach of a collective organization in a Localized Agrifood System (LAS) to grasp collective action processes. The study was conducted in a producers’ association in two municipalities of the Campos de Cima da Serra region, in southern Brazil, where a mountain cheese, the Serrano cheese, is produced. We first conducted social network analyses (SNA) through sociometric interviews with producers’ members of the association, to understand how the different actors of the LAS as well as their relationship patterns frame collective action. Second, an analysis of territorial proximity, conducted through semi-structured interviews with members of the associations, was crossed with the SNA, to observe how the proximities shape social interactions and act as levers to generate collective action. The SNA showed first that networks were centralized, the extension agents having the central position. They are the drivers of collective action, but following a top-down approach. Second, the analysis revealed a lack of trust and reciprocity among producers leading to low level of cooperation. The president of the association played a key brokerage role, essential for the cohesion of the network. Finally, we showed that territorial proximities are instrumental in shaping social interactions in LAS: the less the actors are geographically isolated and the more they participate in cultural life, the more they interact in the association. Hence, territorial proximity appears promising for improving trust, cooperation relations and therefore collective action by increasing interactions among actors.

Das Thema dieser Dissertation sind die räumlichen Veränderungen durch die Zweiteilung der Studiengänge von den ehemaligen Diplom-/Magister- und Staatsexamensabschlüssen hin zu Bachelor- und Masterabschlüssen seit Umsetzung der Bologna-Reform. Dabei wird insbesondere der Aspekt der Studierendenmobilität untersucht, mit welchem weitreichende räumliche Effekte verbunden sind. Dies hängt mit der Homogenisierung und damit einhergehend besseren Vergleichbarkeit der Studienabschlüsse durch die Bologna-Reform, insbesondere der hiermit verbundenen Credit-Point-Struktur der Studiengänge, zusammen. Um diesen Sachverhalt zu untersuchen wird folgendes empirisches Vorgehen genutzt: In drei aufeinander aufbauenden wissenschaftlichen Artikeln werden zum einen mittels Sekundärstatistiken, Daten des Gießener Studierendensekretariats sowie eines Mikrodatensatzes aller deutschen Studierenden die räumlichen Auswirkungen der Bologna-Reform untersucht. So kann festgestellt werden, dass Bachelorstudierende trotz der besseren Vergleichbarkeit der Studiengänge weniger mobil sind als es Studierende der eingliedrigen Studienabschlüsse waren. Die Befunde für Masterstudierende hingegen zeigen, dass diese deutlich distanzunabhängiger in ihrer Studien- und Studienstandortwahl sind. Hier gibt es jedoch fächerbedingte Unterschiede. Während Studierende der Wirtschaftswissenschaften sehr mobil sind und insbesondere im Masterstudium erste arbeitsorientierte Wanderungstendenzen aufweisen, unter-scheiden sich Studierende der Ingenieurswissenschaften im zweigeteilten Studiensystem nur unwesentlich von Studierenden mit dem Abschlussziel Diplom. Die politisch gewünschte Steigerung der Mobilität kann zwar empirisch nachgewiesen werden. Sie variiert jedoch stark zwischen Studienabschlussarten, Fächern und auch Hochschultypen. Hiervon sind insbesondere Hochschulen in ländlichen Regionen betroffen, welche weniger Anziehungskraft für potenzielle Masterstudierende besitzen. Die in dieser Arbeit formulierten Limitationen aufgrund der genutzten Datengrundlage sowie die politischen Handlungsempfehlungen sollen Wege aufzeigen, Studierendenmobilität und deren Auswirkungen und Effekte zu evaluieren und mit Hilfe der vorgeschlagenen Maßnahmen in Zukunft besser zu steuern. Dabei bedarf es nicht nur hochschulspezifischer Projekte, sondern es wird vielmehr ein weiterreichendes regionales Konzept zur verbesserten Sichtbarkeit von Hochschulen benötigt. Zusammen mit Politik, Zivilgesellschaft und Unternehmen vor Ort sollen so die Studienangebote sowie Wege nach dem Studium für Studierende mit den Abschlusszielen Bachelor und/oder Master transparenter und nachhaltiger gestaltet werden. The thematic focus of this dissertation are investigations of the spatial changes through the division of the degree programs of the former diploma, magister and state graduate degrees into bachelor and master degrees. In particular, the aspect of student mobility is examined which is connected to spatial effects. This connection is due to the increased probability of remaining at a place of study after graduation, which undergoes massive change because of the shortened duration of study and the additional decision regarding the master´s degree since the implementation of the Bologna reform. Building on this, the empirical approach is based on the following: In three consecutive scientific articles, the spatial effects of the Bologna reform are examined using secondary statistics, data from the registrar´s office of the Justus-Liebig-University (JLU) Giessen and a microdata record of all German students. Here are some findings that reveal the serious changes caused by the Bologna reform. E.g., undergraduate bachelor students are less mobile than students of one-cycle degrees. However, master´s students show that they are significantly more distance-independent in their choice of study location. Nevertheless, there are subject-related differences. While students of economics are very mobile and show first work-oriented migration tendencies, students of engineering in the two-cycle study system differ only insignificantly from students aspiring diploma degrees. Although the politically desired increase in mobility can be demonstrated empirically, it varies significantly between degree types, subjects and also the type of institute. This particularly affects higher education institutions in rural areas, which are less attractive for po- tential master students of some subjects. The limitations formulated in this work based on the data used and the political recommendations for action can in future be taken to evaluate student mobility and its effects and to be better able to control them with the help of the proposed measures. These activities require more than university-specific projects, but rather a more far-reaching regional concept for improving the visibility of higher education institutions in order to make them attractive to potential students. Cooperations with politics, civil society, and local companies have to be made to attract students with the goal of finishing bachelor and/or master degrees.

International audience; 1. Biodiversity includes multiscalar and multitemporal structures and processes, with different levels of functional organization, from genetic to ecosystemic levels. One of the mostly used methods to infer biodiversity is based on taxonomic approaches and community ecology theories. However, gathering extensive data in the field is difficult due to logistic problems, especially when aiming at modelling biodiversity changes in space and time, which assumes statistically sound sampling schemes. In this context, airborne or satellite remote sensing allows information to be gathered over wide areas in a reasonable time. 2. Most of the biodiversity maps obtained from remote sensing have been based on the inference of species richness by regression analysis. On the contrary, estimating compositional turnover (beta‐diversity) might add crucial information related to relative abundance of different species instead of just richness. Presently, few studies have addressed the measurement of species compositional turnover from space. 3. Extending on previous work, in this manuscript, we propose novel techniques to measure beta‐diversity from airborne or satellite remote sensing, mainly based on: (1) multivariate statistical analysis, (2) the spectral species concept, (3) self‐organizing feature maps, (4) multidimensional distance matrices, and the (5) Rao's Q diversity. Each of these measures addresses one or several issues related to turnover measurement. This manuscript is the first methodological example encompassing (and enhancing) most of the available methods for estimating beta‐diversity from remotely sensed imagery and potentially relating them to species diversity in the field.

International audience; Sequences of lake sediments often form long and continuous records that may be sensitive recorders of seismic shaking. A multi-proxy analysis of Lake Bohinj sediments associated with a wellconstrained chronology was conducted to reconstruct Holocene seismic activity in the Julian Alps (Slovenia). A seismic reflection survey and sedimentological analyses identified 29 homogenite-type deposits related to mass wasting deposits. The most recent homogenites can be linked to historical regional earthquakes (i.e. 1348 AD, 1511 AD and 1690 AD) with strong epicentral intensity [greater than ‘damaging’ (VIII) on the Medvedev–Sponheuer–Karnik scale]. The correlation between the historic earthquake dataset and the homogenites identified in a core isolated from local stream inputs, allows interpretation of all similar deposits as earthquake related. This work extends the earthquake chronicle of the last 6600 years in this area with a total of 29 events recorded. The early Holocene sedimentary record is disturbed by a seismic event (6617 ± 94 yr cal BP) that reworked previously deposited sediment and led to a thick sediment deposit identified in the seismic survey. The period between 3500 to 2000 yr cal BP is characterized by a major destabilization in the watershed by human activities that led to increases in erosion and sedimentation rates. This change increased the lake’s sensitivity to recording an earthquake (earthquake-sensitivity threshold index) with the occurrence of 72 turbidite-type deposits over this period. The high turbidite frequency identified could be the consequence of this change in lake earthquake sensitivity and thus these turbidites could be triggered by earthquake shaking, as other origins are discarded. This study illustrates why it is not acceptable to propose a return period for seismic activity recorded in lake sediment if the sedimentation rate varies significantly.

This dissertation addresses two research gaps in the literature on Chinese cross-border acquisitions (CBAs) in developed economies (DEs). On the one hand, it examines how knowledge transfer (KT) in the context of Chinese CBAs in DEs is organized on the firm level from an organizational learning perspective. On the other hand, against the background of a rising importance of company networks due to the emergence of the knowledge-based economy, it investigates the impact of Chinese CBAs on the existing business-to-business (B2B) customer and supplier relationships of the acquired enterprise. Empirically, this thesis employs a multiple case study and investigates Chinese acquisitions in the German industrial sector as a representative sample of Chinese CBAs in DEs. In addition, this thesis carries out a systematic review of the academic literature on the internationalization of Chinese firms (ICF) published between 2011 and June 2017, supplementing a previous review article on this subject by Deng (2012) and ensuring that the empirical investigation is based on the most recent research results. The findings of this dissertation reveal that the management actions to achieve KT in the context of Chinese CBAs in DEs include the establishment of jointly operated R&D centers and joint ventures, as well as the reaching of license agreements between the Chinese parent company and the acquired target firm. Additional management measures include the training of employees, the formation of international project teams, the ue of digital communication tools, and the posting of employees abroad. Another central finding of this thesis is that while the dominant KT direction remains from the acquired enterprise to the Chinese parent company and knowledge transmission in particular concerns the technological area, KT meanwhile also occurs bi-directionally. The effectiveness of the KT process is moderated by the absorptive and disseminative capacities of the employees of the Chinese parent company and the acquired firm, knowledge characteristics, and the handling of intercultural issues. Furthermore, the research results of this dissertation demonstrate that Chinese CBAs in DEs hardly lead to significant and permanent adverse effects on the existing B2B customer and supplier network of the acquired enterprises from DEs. The rather preserving integration behavior of Chinese acquirers, the long-term strategic orientation of the Chinese parent com-panies and the involvement of key customers during the negotiation phase explain this result.

Poster; Julian Alps are characterised by a moderate to high seismic activity that has included several destructive earthquakes, such as the 1511 AD “Idrija” earthquake (MSK = X). Accurate assessment of the seismic hazard is required to reduce the high vulnerability of this region. Earthquake shaking may destabilise previously deposited sediment, which slides to the bottom of the lake and formed seismically induced mass wasting deposits (MWD), such as turbidites or homogenites.

A better understanding of regional-scale precipitation patterns in the Himalayan region is required to increase our knowledge of the impacts of climate change on downstream water availability. This study examines the impact of four cloud microphysical schemes (Thompson, Morrison, Weather Research and Forecasting (WRF) single-moment 5-class, and WRF double-moment 6-class) on summer monsoon precipitation in the Langtang Valley in the central Nepalese Himalayas, as simulated by the WRF model at 1 km grid spacing for a 10 day period in July 2012. The model results are evaluated through a comparison with surface precipitation and radiation measurements made at two observation sites. Additional understanding is gained from a detailed examination of the microphysical characteristics simulated by each scheme, which are compared with measurements using a spaceborne radar/lidar cloud product. Also examined are the roles of large- and small-scale forcings. In general, the schemes are able to capture the timing of surface precipitation better than the actual amounts in the Langtang Valley, which are predominately underestimated, with the Morrison scheme showing the best agreement with the measured values. The schemes all show a large positive bias in incoming radiation. Analysis of the radar/lidar cloud product and hydrometeors from each of the schemes suggests that “cold-rain” processes are a key precipitation formation mechanism, which is also well represented by the Morrison scheme. As well as microphysical structure, both large-scale and localized forcings are also important for determining surface precipitation.

The planning system of Kabul City was strongly influenced by the Soviet master planning attempts, which started in the 1960s and continued to prevail until the end of the twentieth century. Despite the Soviet master plans were not fully implemented, their strong impact is still evident in the planning system of Afghanistan. An important event which had an immense negative impact on the development Kabul was the civil war of 1992 -1996, in which, the majority of the city’s infrastructure was destroyed and the social fabric of the city was torn apart. This was followed by the five-year rule of the Taliban, which prevented any reconstruction effort. The fall of the Taliban Regime in Afghanistan and establishment of the new government was an important milestone for the development of Kabul City. The relative stability of the post-Taliban Kabul paved the way for vast reconstruction efforts. Meanwhile, the massive return of the refugees and internally displaced people to major cities, especially Kabul, resulted in the emergence of many new challenges. Over seventy percent of the Kabul City area was occupied by informal settlements with no or limited access to basic services and infrastructure. The new situation was involved with conflict of planning ideas for the future of Kabul City. The ideas varied from reviving of the Soviet master plans to new planning solutions for the existing city and as well as the proposal for a new city in the north of the existing Kabul City. The major urban planning and management efforts for post-conflict Kabul includes the preparation of the Development Plan for Kabul in 2008, which was funded by the World Bank and carried out by ICT, an Indian company; revision of ICT plan by JICA team in 2011; and preparation of the Master Plan for Kabul New City in Dehsabz by JICA in 2009. Moreover, several independent construction and reconstruction projects were implemented in Kabul City, which was not part of any of the mentioned large-scale city development plans. The large-scale master plans for Kabul City and Kabul New City were influenced by utopian concepts, which in many cases did not fit to the socio-economic context of Afghanistan. The study and assessment of the various planning and management attempt for post-Taliban Kabul indicate the fact that none of the large-scale master plans did make their way to implementation stages. Therefore, it was concluded that the large-scale top-down city level master plans, despite of consuming large amounts of resources and time, were not able to address the fundamental problems and issues of urban planning and management of post-Taliban Kabul. Nevertheless, feasibility and applicability of smaller scale project have been more than the large-scale utopian concepts. The independent projects have been more efficient and have tangible results. Although, in some cases, the lack of coordination among various city-level projects resulted in the inefficient implementation of some projects and waste of the resources. Therefore, substitution of the prevailing large-scale top-down planning system with a bottom-up system of city planning, based on the coordination of various city-level projects, was suggested and recommended.

A global compilation of glacier advances and retreats for the past two millennia grouped by 17 regions (excluding Antarctica) highlights the nature of glacier fluctuations during the late Holocene. The dataset includes 275 time series of glacier fluctuations based on historical, tree ring, lake sediment, radiocarbon and terrestrial cosmogenic nuclide data. The most detailed and reliable series for individual glaciers and regional compilations are compared with summer temperature and, when available, winter precipitation reconstructions, the most important parameters for glacier mass balance. In many cases major glacier advances correlate with multi-decadal periods of decreased summer temperature. In a few cases, such as in Arctic Alaska and western Canada, some glacier advances occurred during relatively warm wet times. The timing and scale of glacier fluctuations over the past two millennia varies greatly from region to region. However, the number of glacier advances shows a clear pattern for the high, mid and low latitudes and, hence, points to common forcing factors acting at the global scale. Globally, during the first millennium CE glaciers were smaller than between the advances in 13th to early 20th centuries CE. The precise extent of glacier retreat in the first millennium is not well defined; however, the most conservative estimates indicate that during the 1st and 2nd centuries in some regions glaciers were smaller than at the end of 20th/early 21st centuries. Other periods of glacier retreat are identified regionally during the 5th and 8th centuries in the European Alps, in the 3rd–6th and 9th centuries in Norway, during the 10th–13th centuries in southern Alaska, and in the 18th century in Spitsbergen. However, no single period of common global glacier retreat of centennial duration, except for the past century, has yet been identified. In contrast, the view that the Little Ice Age was a period of global glacier expansion beginning in the 13th century (or earlier) and reaching a maximum in 17th–19th centuries is supported by our data. The pattern of glacier variations in the past two millennia corresponds with cooling in reconstructed temperature records at the continental and hemispheric scales. The number of glacier advances also broadly matches periods showing high volcanic activity and low solar irradiance over the past two millennia, although the resolution of most glacier chronologies is not enough for robust statistical correlations. Glacier retreat in the past 100–150 years corresponds to the anthropogenic global temperature increase. Many questions concerning the relative strength of forcing factors that drove glacier variations in the past 2 ka still remain.

International audience

In dieser Dissertation werden erstens die Methodenverständnisse von Planungswissenschaftlern und Planungspraktikern analysiert und zweitens Hemmnisse und Gelin-genskriterien identifiziert, die beim Methodeneinsatz in der räumlichen Planung auftreten können. Das Ziel dieser Arbeit ist es, ein Bewusstsein für den Begriff Methoden und für den Methodeneinsatz zu schaffen. Das Forschungsdesign setzte sich aus einer Expertenstudie mit leitfadengestützten Experteninterviews sowie einer vergleichenden Fallstudienanalyse zusammen. Die Expertenstudie bestand aus 22 Interviews mit Planerinnen und Planern, die inhaltsanalytisch ausgewertet wurden. Zusätzlich wurde eine deskriptive Auswertung hinsichtlich der Bekanntheit und Anwendung von Methoden durchgeführt. Diese Daten dienten für eine Typenbildung mittels einer Clusteranalyse. Anhand der Fallstudienanalyse wurde der Methodeneinsatz in zwei Projekten der Sozialen Stadt West und zwei Stadtumbauprojekten in Frankfurt a.M. und Fulda untersucht. Dazu wurden 32 qualitative Interviews durchgeführt und inhaltsanalytisch ausgewertet sowie Dokumente analysiert. Zudem erfolgte eine Einordnung der Ergebnisse der Experten- und der Fallstudie in das „Planungsmodell der dritten Generation“ von SCHÖNWANDT (2002). In der Expertenstudie wurden folgende Hemmnisse und Gelingenskriterien aufgezeigt, die beim Methodeneinsatz auftreten können: fehlende Ressourcen, fehlende Metho-denkompetenz, Theorie-Praxis-Gap, Überforderung durch Methoden und Methodenüberdruss (Hemmnisse) sowie Methodenkompetenz, Flexibilität, die Anwendung verständlicher Methoden, Kommunikation und eine Methodenreflexion (Gelingenskriterien). In der Fallstudienanalyse wurde der Methodeneinsatz an vier konkreten Planungsprozessen nachvollzogen sowie die identifizierten Hemmnisse und Gelingenskriterien überprüft. Die Analyse der Methodenverständnisse der Planungswissenschaftler sowie der Planungspraktiker zeigt, dass die Begriffe unterschiedlich wahrgenommen und definiert werden und eine Vielzahl an unterschiedlichen Definitionen vorliegt. Eine Empfehlung ist daher, die Methodenreflexion im Planungsalltag zu fördern, um den Methodeneinsatz nachzuvollziehen und ggf. zu verbessern.

[Departement_IRSTEA]Eaux [TR1_IRSTEA]ARCEAU [ADD1_IRSTEA]Hydrosystèmes et risques naturels; Summary Flash floods represent one of the most destructive natural hazards in the Mediterranean region. These floods result from very intense and spatially heterogeneous rainfall events. Distributed hydrological models are valuable tools to study these phenomena and increase our knowledge on the main processes governing the generation and propagation of floods over large spatial scales. They are generally built using a bottom\textendashup approach that generalizes small-physics representations of processes. However, top\textendashdown or data-driven approach is increasingly shown to provide also valuable knowledge. A simplified semi-distributed continuous hydrological model, named SIMPLEFLOOD, was developed, based on the simple dynamical system approach (SDSA) proposed by Kirchner (WRR, 2009, 45, W02429), and applied to the Ardèche catchment in France (2388km2). This data-driven method assumes that discharge at the outlet of a given catchment can be expressed as a function only of catchment storage. It leads to a 3-parameter nonlinear model according to rainfall and runoff observations. This model was distributed over sub-catchments and coupled with a kinematic wave based flow propagation module. The parameters were estimated by discharge recession analyses at several gauged stations. Parameter regionalization was conducted using a Factorial Analysis of Mixed Data (FAMD) and Hierarchical Classification on Principal Component (HCPC) in order to find relationships between the SDSA approach and catchments characteristics. Geology was found to be the main predictor of hydrological response variability and model parameters were regionalized according to the dominant geology. The SIMPLEFLOOD model was applied for a 12-year continuous simulation over the Ardèche catchment. Four flash flood events were also selected for further analysis. The simulated hydrographs were compared with the observations at 11 gauging stations with catchment size ranging from 17 to 2300km2. The results show a good performance of the model for the continuous and flash flood events occurring under wet conditions, whereas the model underestimates discharge for events occurring after a long dry period. The simple modeling approach provided interesting insight into the Ardèche catchment functioning and offers perspective for a better simulation of flash floods, mainly under wet conditions.

International audience; The presence of water at volcanic vents can have dramatic effects on fragmentation and eruption dynamics, but little is known about how the presence of particulate matter in external water will further alter eruptions. Volcanic edifices are inherently "dirty" places, where particulate matter of multiple origins and grainsizes typically abounds. We present the results of experiments designed to simulate non-explosive interactions between molten basalt and various "coolants," ranging from homogeneous suspensions of 0 to 30 mass% bentonite clay in pure water, to heterogeneous and/or stratified suspensions including bentonite, sand, synthetic glass beads and/or naturally-sorted pumice. Four types of data are used to characterise the interactions: (1) visual/video observations; (2) grainsize and morphology of resulting particles; (3) heat-transfer data from a network of eight thermocouples; and (4) acoustic data from three force sensors. In homogeneous coolants with ~20% sediment, heat transfer is by forced convection and conduction, and thermal granulation is less efficient, resulting in fewer blocky particles, larger grainsizes, and weaker acoustic signals. Many particles are droplet-shaped or/and "vesicular," containing bubbles filled with coolant. Both of these particle types indicate significant hydrodynamic magma-coolant mingling, and many of them are rewelded into compound particles. The addition of coarse material to heterogeneous suspensions further slows heat transfer thus reducing thermal granulation, and variable interlocking of large particles prevents efficient hydrodynamic mingling. This results primarily in rewelded melt piles and inefficient distribution of melt and heat throughout the coolant volume. Our results indicate that even modest concentrations of sediment in water will significantly limit heat transfer during non-explosive magma-water interactions. At high concentrations, the dramatic reduction in cooling efficiency and increase in mingling help to explain globular peperite, and provide information relevant to analyses of premixing associated with highly-explosive molten fuel-coolant interactions in debris-filled volcanic vents.

Poster; International audience; Les Alpes Juliennes sont caractérisées par une activité tectonique importante et souvent destructrice.

International audience; We present results of experiments that use small chemical explosive charges buried in layered aggregates to simulate the effects of subsurface hydrothermal and phreatomagmatic explosions at varying depths and lateral locations, extending earlier experimental results that changed explosion locations only along a vertical axis. The focus is on the resulting crater size and shape and subcrater structures. Final crater shapes tend to be roughly circular if subsurface explosion epicenters occur within each other’s footprints (defined as the plan view area of reference crater produced by a single explosion of a given energy, as predicted by an empirical relationship). Craters are elongate if an epicenter lies somewhat beyond the footprint of the previous explosion, such that their footprints overlap, but if epicenters are too far apart, the footprints do not overlap and separate craters result. Explosions beneath crater walls formed by previous blasts tend to produce inclined (laterally directed) ejecta jets, while those beneath crater centers are vertically focused. Lateral shifting of explosion sites results in mixing of subcrater materials by development of multiple subvertical domains of otherwise pure materials, which progressively break down with repeated blasts, and by ejection and fallback of deeper-seated material that had experienced net upward displacement to very shallow levels by previous explosions. A variably developed collar of material that experienced net downward displacement surrounds the subvertical domains. The results demonstrate key processes related to mixing and ejection of materials from different depths during an eruptive episode at a maar-diatreme volcano as well as at other phreatomagmatic and hydrothermal explosion sites.

Topographische Kenntnisse und Fähigkeiten haben nicht nur nach der Meinung gesellschaftlicher Spitzenrepräsentanten und Geographieexperten einen hohen Stellenwert, sondern auch aus waldorfpädagogischer Sicht sind sie für die Bildung und die Persönlichkeitsentwicklung bzw. Selbstkompetenz des jungen Menschen von Bedeutung. Insofern bietet es sich an, den Erdkundeunterricht an Waldorfschulen gerade an diesem ganz entscheidenden Bereich näher zu beleuchten. Die topographischen Kenntnisse und Fähigkeiten werden dabei in der vorliegenden Arbeit im Sinne der Bildungsstandards in fünf Dimensionen gegliedert, die zusammen den Kompetenzbereich der Räumlichen Orientierung bilden. In verschiedenen Studien sind die Istwerte von Schülerinnen und Schülern der Regelschule zu diesem Kompetenzbereich untersucht worden, am umfangreichsten 2008/09 in einer Querschnittstudie, die deshalb als Vergleichsgrundlage für die hier vorliegende Arbeit herangezogen wurde. Außerdem sind die Einflussfaktoren, die die Ausprägung dieser Kenntnisse und Fähigkeiten bestimmen, in diversen Untersuchungen herausgearbeitet worden. In der vorliegenden Studie wird untersucht, ob sich die Lernergebnisse der Schülerinnen und Schüler der Waldorfschule in diesem Kompetenzbereich von denen der Regelschule sowohl in ihrer Ausprägung als auch in der Wirksamkeit der Einflussfaktoren unterscheiden. Die Grundlage für die Annahme von Unterschieden ist die aus der Literatur abgeleitete Feststellung, dass die Waldorfschule als ein besonderer Schultyp innerhalb der klassischen Reformpädagogik ein anderes Lehrplankonzept verfolgt und anderen Einflussfaktoren unterliegt. Um dieses Lehrplankonzept für das Fach Erdkunde und damit auch für die Vermittlung topographischer Kenntnisse und Fähigkeiten in seiner realen Umsetzung genauer zu erfassen, wurden 58 Lehrkräfte von 38 Waldorfschulen in fokussierten Interviews befragt. Dabei konnte festgestellt werden, dass die Waldorfschulen trotz einiger individueller Abweichungen ein relativ homogenes Konzept im Fach Erdkunde bis zur 10. Klasse praktizieren, das in der vorliegenden Arbeit genauer vorgestellt wird. Als Einflussfaktoren, die sich neben der Qualität des Unterrichts, die die einzelne Lehrkraft zu verantworten hat, auf die schulische Vermittlung von Räumlicher Orientierung auswirken könnten, wurden aufgrund der Untersuchung des Forschungsstandes vor allem motivationale Aspekte, der besondere soziokulturelle Hintergrund, ein zwischen dem Niveau der Realschule und des Gymnasiums anzunehmendes kognitives Ausgangsniveau und Besonderheiten in der Lehrerausbildung ermittelt. Vor diesem Hintergrund sind die Ergebnisse der Schülerbefragung zu betrachten, die im Rahmen der vorliegenden Arbeit im Schuljahr 2012/13 bei 616 Schülerinnen und Schülern am Ende der 10. Klasse an 18 Waldorfschulen in drei Bundesländern durchgeführt wurde, wobei Vergleichswerte zu den verschiedenen Schultypen der Regelschule vorlagen. Legt man das anzunehmende kognitive Ausgangsniveau zwischen Realschule und Gymnasium als Maßstab zugrunde, so erzielen die Schülerinnen und Schüler der Waldorfschulen in vielen Bereichen der Räumlichen Orientierung durchschnittliche bis signifikant überdurchschnittliche Ergebnisse und nur in einigen wenigen Bereichen, etwa bei den Items zu politisch administrativen Strukturen, waren Defizite feststellbar. Bei den Einflussfaktoren, die für diese Ergebnisse mitverantwortlich sind, erweisen sich nach den Ergebnissen der Schülerbefragung vor allem motivationale Faktoren sowie einige Faktoren des soziokulturellen Hintergrunds als signifikant wirksam. Auch die Bundeslandzugehörigkeit spielt entgegen der Erwartung eine gewisse Rolle, ebenso der erstmals empirisch erfasste Faktor der Größe des Schulstandorts. Im Unterschied zur Regelschule hat der soziale Status an der Waldorfschule augenscheinlich keine Bedeutung für die Lernleistung, auch die Geschlechtszugehörigkeit spielt eine deutlich geringere Rolle. Auch wenn die Schülerinnen und Schüler der Waldorfschulen bei der Ausprägung topographischer Kenntnisse und Fähigkeiten durchaus mit denen der Regelschulen mithalten und sie partiell signifikant übertreffen können, bleibt doch das Ergebnis vor allem im Bereich des basalen Orientierungswissens hinter den Sollwertstudien zurück. Daher werden in der vorliegenden Arbeit abschließend einige Vorschläge unterbreitet, wie das Ergebnis in Zukunft optimiert werden könnte. Die Regelschulen wiederum könnten von der Übernahme einiger Paradigmen der Waldorfschule profitieren. Dazu sind aber noch einige Forschungsdesiderate, die zum Abschluss der Studie genannt werden, in Angriff zu nehmen.

International audience; Holocene glacier records from the western European Alps are still sparse, although a number of sites are well suited to constraining pre- and early- Little Ice Age (LIA) glacier advances. The present study provides the first dendrochronologically-based and calendar-dated Neoglacial glacier chronology for the Mont Blanc massif, French Alps. It is based on the analysis of over 240 glacially buried Pinus cembra subfossil logs and wood remains found either embedded-in-till or as detrital material in the Mer de Glace right lateral moraine. Only a few of the samples were found to be ‘formally in situ’ but we show that some logs were ‘virtually in situ’ (not rooted but showing little or no evidence of reworking) and could be used to accurately reconstruct past glacier margin behavior in space and time. Uncertainties regarding the other samples may relate to original growth location and/or to outer wood decay. The resulting dates (followed by a ‘+’) were therefore considered maximum-limiting ages for glacier advances. The main burial events – interpreted as glacier advances – occurred between ca 1655+ and 1544+ BC, between ca 1230+ and 1105+ BC, between ca 1013+ and 962+/937+ BC, at ca 802–777 BC, after 608+ BC, between 312 and 337 AD, between ca 485+ AD and 606+ AD, between 1120 and 1178 AD, between ca 1248 and 1278+/1296 AD, and after 1352+ AD. These advances predate the late LIA maxima known from historical sources. The magnitude of the advances gradually increased to culminate in three near-Neoglacial maxima during the 7th, 12th and 13th centuries AD, followed by a first LIA/Neoglacial maximum in the second half of the 14th century AD. The pattern of Neoglacial events described here is coherent with Central and Eastern Alpine glacier chronologies. This indicates marked synchronicity of late Holocene glacier variability and forcing at a regional scale, although occasional differences could be detected between ‘Western’ and ‘Eastern’ records. The Mer de Glace record also confirms the link between the timing of sediment erosion in a high-elevation glaciated Alpine catchment and subsequent deposition in the sub-alpine Lake Bourget.