Dissertationsprojekte

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Modelling snow cover dynamics in high mountain areas of the Himalayan range.

Johannes Weidinger, M.Sc.
Johannes.Weidinger"AT"uni-hamburg.de

Betreuung durch:  Prof. Dr. Jürgen Böhner

Laufzeit: 2016 - 2019

Projektbeschreibung:
The integration of robust snow cover or snow parameter models as reliable input information is a classic feature in hydrological runoff simulations or ecological habitat modelling (Carlson et al. 2015, Rohrer et al. 2013, Shrestha et al. 2012, Hiemstra et al. 2006). On account of the fact that snow cover is one of the most dynamic aspects of the cryosphere from a (intra)diurnal or seasonal point of view (Qu et al. 2006: 155), it is additionally expected to be one of the fastest changing climate features under current climate warming (IPCC, 2007). The close relationship between the spatial distribution of snow cover and plant communities eventually leads to major impacts on mountain ecosystems and their biota (Chen et al. 2011, Grabherr et al. 2010, Litaor et al. 2008). General circulation models are able to predict large scale climate variations in global dimensions, but dynamic small scale characteristics, such as rapid snow melt and its temporal alterations in high mountain regions are not represented sufficiently. Regional climate models with nesting provide an enhancement in case of horizontal resolution but come along with their own unique shortcomings, especially with the complex topography of the Central Himalayas (Pedersenand Egholm 2013: 206). Since high mountain areas, are generally remote, it is difficult to obtain data in high spatio-temporal resolutions (Gerlitz 2014). Earth observation systems, such as MODIS allow bridging this gap partly and offer snow (cover) data in daily temporal and medium spatial resolution, which can be applied as evaluation and training data for hydrological and statistical approaches. Nevertheless high spatial resolution remote sensing systems fail to generate surface data under cloudy conditions which are dominant during the highly seasonal climate (summer and winter monsoon) along the Himalayas. In Combination with reanalysis data such as ERA-Interim or MERRA data gaps and disadvantages of certain products can be enhanced and high spatio-temporal resolution environmental parameter data derived. Additional an existing meteorological network (between 3700 and 5100 m. a.s.l.) of the TREELINE project installed in the Rolwaling Himal, Nepal will serve as point observation to validate different modelling approaches (Schwab et al. 2015: 88). Within this thesis (combined) snow distribution models and snow recession models will be implemented for a research domain in the Rolwaling Himal (Nepal), employing state of the art machine learning algorithms. Bottom-up strategies provide inductive reasoning to derive rules for snow related processes out of climate and climate-related topographic data sets obtained by meteorological network stations and GIS. Daily snow distribution and several other environmental parameters will be predicted reliably in the research area, whereas further effort is necessary for predicting snow cover recession processes adequately. Both approaches underline the technical difficulties of snow cover modelling during the monsoon season, in accordance with previous studies. 

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Dynamical downscaling of climate fields in convection-permitting resolutions over complex mountainous terrain of Nepalese Himalaya.

Ramchandra Karki
Ramchandra.Karki"AT"studium.uni-hamburg.de

Betreuung durch: Prof. Dr. Jürgen Böhner

Laufzeit: 2015 - 2018

Projektbeschreibung:
In order to understand the meso/microscale atmospheric processes in the highly complex Himalayan terrain of Nepal, and to achieve how the present and future climate will vary across the different altitudinal range, dynamical downscaling particularly using Weather Research and Forecasting (WRF) model in kilometer to sub-kilometer spatial scale is being implemented in my PhD research work.

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Modelling Environmental and Social Impacts of Bioenergy from Oil Palm Cultivation in Nigerian Niger Delta.

Stanley Okoro, M.Sc.
Stanley.Okoro"AT"uni-hamburg.de

Betreuung durch: Prof. Dr. Udo Schickhoff

Laufzeit: seit 2014

Projektbeschreibung:
The increasing demand for bioenergy due to its climate mitigation ability has been promoting the expansion of a number of agricultural commodities; this includes oil palm (Elaeis guineensis).The commercial cultivation of oil palms and other bioenergy crops has been leading to competition with food and environmental degradation, causing one of the major issues confronting many governments around the world. This problem has been acute especially in developing countries where there is often a lack of understanding of environmental and societal interactions with respect to land use issues. My project is aimed to employ the integration of Remote Sensing, GIS and Constraint Optimization Modelling approach with the view to evaluate the environmental and social impacts of bioenergy production from oil palm cultivation on the Nigerian Niger Delta environment.

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Pastoral Resources in the Naryn Area, Kyrgyz Republic, under Post-Socialist Transformation - Analysis, Monitoring and Forecasting

Franziska Hoppe, M.Sc.
Franziska.Hoppe"AT"uni-hamburg.de

Betreuung durch: Prof. Dr. Udo Schickhoff

Laufzeit: seit 2014

Projektbeschreibung:
Animal husbandry in mountainous regions has always played a major role in the life of Kyrgyz people and the livestock sector has been one of the strongest components of the regional economy during Soviet and post-Soviet times.Montane and alpine rangelands, which occupy 45% of the Kyrgyzstan’s land area, represent the significant basis for this economic sector. During the Soviet regime the livestock industry had been massively expanded. The first years after independence saw, a drastic reduction in livestock numbers, and a temporarily decreasing grazing pressure. However, in the further course of post-Soviet transformation livestock numbers have been considerably increasing again. By current estimates, at least 25-35 % of pasture areas are subject of vegetation and soil degradation. Using an interdisciplinary approach, the project TRANSPAST aims at assessing the capability of rangeland ecosystems to cope with increased grazing pressure, and at predicting the future pastoral resource availability under different land use scenarios. Based on collected data in the field, as well as their evaluation and including socio-economic aspects, a comprehensive understanding of human-environment interactions will be developed. In addition the project intends to predict the future pastoral resource availability under different land use scenarios, and to provide management suggestions.

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Bridging the Gap between Scales in Monitoring and Modeling Climate and Land Cover Feedback in a high mountain treeline ecotone in NE Nepal

Eleonore Schenk
Eleonore.Schenk"AT"uni-hamburg.de

Betreuung durch: Prof. Dr. Jürgen Böhner

Laufzeit: seit 2014

Projektbeschreibung:
The research entailed in this PhD thesis links the three research projects TREELINE, CLASH and LOWQM, all dealing with different impacts of climate change on the geo-ecosystems of High Asia. All three projects rely on high resolution climate data which are not readily available from measurements in the remote regions of High Asia and have to be derived by atmospheric modeling through an integrated dynamical and statistical downscaling approach. One of the goals of this PhD project to find an optimal configuration of the atmospheric model WRF-ARW (Weather Research and Forecasting Model - Advanced Research WRF) for the regionalization of hydroclimatic variables for two study regions in High Asia with different precipitation regimes and to quantify the added-values of the chosen dynamical downscaling approach. Furthermore, it is intended to model and analyze the effects of climate change on the treeline ecotone in Rolwaling Himal, Nepal by the means of a SVAT- model driven by the generated high-resolution atmospheric data.

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Treeline dynamics at Rolwaling Himal

Dipl. Geogr. Niels Schwab
Niels.Schwab"AT"uni-hamburg.de 

Betreuung durch: Prof. Dr. Udo Schickhoff

Laufzeit: seit 2013

Projektbeschreibung:
While at global scale plant growth limitation by low-temperature determines the position of natural alpine treelines, at smaller scales the factors and mechanisms influencing treeline characteristics are not well understood. Main objective of the project TREELINE is to detect the hitherto poorly understood driving forces for spatially differentiated treeline dynamics. As our study area, the secluded Rolwaling valley provides one of the rare near-natural Himalayan treelines with negligible human impact.
Forest ecological and dendroecological data and their analyses’ results will be this work’s contribution to TREELINE’s integrated landscape approach model. Appropriate forest and vegetation sampling methods will be applied at Rolwaling during extensive field campaigns. Open source GIS and statistics software (SAGA-GIS, R) will be used to elaborate and visualize results. Major tasks are to investigate age structure of stands and annual radial increment of trees for changes, with the aim of describing treeline dynamics at different positions of the valley’s slopes. Increments will be tested for correlation with data from high resolution climate modelling (see projects of E. Rauch and L. Gerlitz, both Hamburg). Moreover the spatial effectiveness of other relevant abiotic and biotic site factors, e.g. soil conditions and ground vegetation (see projects of M. Müller, Tübingen and B. Bürzle, Hamburg), will be analysed to explain spatially non-uniform treeline response patterns.

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Statistical Downscaling of precipitation in Amazonia

Tobias Kawohl, M.Sc.
tobias.kawohl"AT"uni-hamburg.de

Betreuung durch: Prof. Dr. Udo Schickhoff

Laufzeit: seit 2013

Projektbeschreibung:
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Parametrisierung von Oberflächenabfluss auf landwirtschaftlich genutzten Flächen zur Abschätzung diffuser Stoffeinträge in Gewässer-Ökosysteme

Sandra Wendland, M.Sc.
Sandra.Wendland"AT"uni-hamburg.de

Betreuung durch: Prof. Dr. Jürgen Böhner

Laufzeit: seit 2013

Projektbeschreibung:
Nähr- und Schadstoffausträge von intensiv landwirtschaftlich genutzten Flächen können die Funktion angrenzender Ökosysteme nachteilig beeinflussen oder beeinträchtigen. Neben dem partikulären Transport von Bodenmaterial resp. Nähr- und Schadstoffen durch Bodenerosionsprozesse führt auch Oberflächenabfluss und der damit verbundene Transport gelöster Stoffe zu on-site Verlusten von produktionsrelevanten Nährstoffen sowie zu unerwünschten off-site Stoffeinträgen, selbst wenn die beteiligten Teilprozesse (Sättigungsabfluss, Hortonscher Landoberflächenabfluss) nicht erosiv wirksam sind. Während für die schlagbezogene Abschätzung von Erosionsrisiken eine Reihe etablierter statistischer und numerischer Modelle sowie praxistaugliche GIS-Applikationen zur Verfügung stehen, stellt die quantitative Erfassung potenzieller und aktueller on-site und off-site Risiken durch Oberflächenabfluss nach wie vor ein relevantes wissenschaftsmethodisches Problem dar. Vor diesem Hintergrund sollen im Rahmen des Dissertationsprojektes unterschiedliche Oberflächenabflussmodelle validiert und mit GIS-basierten geometrisch-topologischen Analysen verknüpft werden, um eine räumlich explizite quantitative Erfassung der Risikodisposition durch Oberflächenabfluss zu ermöglichen. Das Promotionsvorhaben ist eingebunden in eine Forschungskooperation mit Bayer CropScience (BCS) und zielt auf die Entwicklung eines WebGIS-basierten Diagnosis & Advisory Tools, das im Rahmen der landwirtschaftlichen Beratung die Auswahl geeigneter Managementstrategien zur präventiven Minderung von Produktionsrisiken sowie zum Erhalt von Bodenfruchtbarkeit und Ökosystemfunktionen unterstützen soll.

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Sensitivity of treeline at Rolwaling Himal to global warming – Analyses of vegetation and regeneration processes

Dipl. Biogeog. Birgit Bürzle
Birgit.Buerzle"AT"uni-hamburg.de

Betreuung durch: Prof. Dr. Udo Schickhoff

Laufzeit: seit 2013

Projektbeschreibung:
Climate warming is expected to induce treelines to advance to higher elevations since, at a global scale, low-temperature growth limitation determines the position of natural alpine treelines. On a regional and local scale, however, treeline position, form (spatially pattern), and dynamics depend on multiple interactions of influencing factors and mechanisms. Thus empirical studies give evidence of both advancing treelines as well as rather insignificant responses. This inconsistency of findings is not well understood and pointing to considerable research deficits, concerning the effects of global and local factors. Furthermore, past treeline studies mainly focused on the response of mature trees (e.g. growth, growth form) to climate warming. Since treeline advance particularly depends on successful dispersal of seeds and the survival of young seedlings, future assessments have in particular to consider the response of pre-established life stages to climate warming.
Integrating field sampling/mapping and experimental treatments, the PhD project aims at investigating the sensitivity and response of the treeline ecotone in Rolwaling Himal, Nepal, to climate warming. Focusing on tree recruitment and regeneration processes, treeline response will be analysed by correlating patterns of naturally established seedlings with microhabitat conditions and mechanisms (e.g. plant interactions associated with facilitation, competition, feedback systems, shelter elements). In order to explore the future potential for climate change-induced treeline advance, regeneration analyses will be complemented by an experimental approach using open top chambers (OTCs).

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Modelling changing distribution ranges of Himalayan plant species under climate change conditions

Maria Bobrowski, M.Sc.
Maria.Bobrowski"AT"uni-hamburg.de

Betreuung durch: Prof. Dr. Udo Schickhoff

Laufzeit: seit 2013

Projektbeschreibung:
Global warming and other global environmental changes (e.g. habitat loss and fragmentation, accumulation of nutrients and pollutants, biological invasions) are increasingly threatening biodiversity and ecosystem services. Due to above-average warming rates high latitude and high altitude regions are particularly susceptible to climate warming effects. Recent observational, experimental and modelling work has pointed to major changes in arctic and montane ecosystems as a result of climate change. Significant changes in the distribution of species and ecosystems have to be expected. A number of different modelling approaches has been developed such as Maxent and BIOMOD, forecasting future species distributions under climate change conditions. Hitherto published results of respective modelling studies primarily refer to plant species and communities of the European Alps. For the Himalayan mountain range, species or habitat distribution modelling studies have not been conducted so far. It is therefore the objective of this thesis to investigate how and to what extent Himalayan plant species distribution ranges may change or shift under climate change conditions. In order to predict future distribution ranges, species distribution modelling will be applied based on geocoded information on current species distributions and quantified environmental niches of species.

Upgrading, competitive strategies, and uneven development. Embedding upgrading of Argentinian soft commodity chains in its political-economic environment. (working title)

Christin Bernhold (Universität Zürich)

Betreuung durch: Prof. Dr. Christian Berndt, Prof. Dr. Christof Parnreiter, Prof. Dr. Víctor Ramiro Fernandez, Prof. Dr. Benedikt Korf

Laufzeit: 2013-2017

Projektbeschreibung:
Within economic geography, much of today’s research on the interweaving of local developments and global political economy draws from conceptual frameworks such as global commodity or value chains (GCCs/GVCs), and global production networks (GPNs). However, while GCC research was initially intended to critically analyze uneven development and center-periphery relations in the global political economy, many academics have sidelined issues of inequality and social antagonisms. Instead, scholars and policy makers increasingly focus on upgrading. The latter is regarded as being critical for achieving socio-economic progress.

My PhD-project is designed as an empirically informed ideology critique of upgrading as a new paradigm for development. Critical political economy comprises my theoretical framework: I seek to strengthen approaches that analyze how social relations of production shape both upgrading strategies and its social outcomes with respect to inequality and variation over uneven geographies of capitalism. Yet, my research is strongly based on empirical work, designed as a multi-sited endeavor that relies on semi-structured interviews, text corpora, and quantitative data. First, it investigates competitive and upgrading strategies of companies and business associations (as well as their limits) in the soy agro-industrial chain in Argentina, especially in the Pampa region. Second, it looks at contradictory and unequal socio-economic outcomes of soy chain upgrading and at how historically modifying social relations, and economic as well as politico-ideological struggles shape them.

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The rise of finance in the wind industry - Financialization in global commodity chains. The German onshore wind energy market as a case study (working title)

Philipp Jantz, M.Sc.
philipp.jantz@studium.uni-hamburg.de

Betreuung durch: Prof. Dr. Christof Parnreiter, Prof. Dr. Jürgen Oßenbrügge

Laufzeit: 2014-2017

Projektbeschreibung:
The energy revolution represents one of the greatest challenges of our times. Wind energy plays a special role within this implementation of sustainable energy supply. The increasing complexity of wind park planning, construction and operation, initiated by policy and economy, as well as the required targets for transferring renewable energies into a free market, is a difficult task for wind energy projects in Germany today and will be in the future as well. Hereby the main challenge will be to operate a wind energy project economically stable despite fluctuating feed-in tariffs, changes of the political framework and negative electricity prices. The wind industry and the financial sector are addressing these new challenges with ever new ideas. In this context, an analysis from the perspective of the Global Commodity Chain approach will be presented, which will show the exchange relations between the wind industry and the financial sector and explain changes and shifts in this system. The aim is to analyze what influence the financial sector has on the development of wind energy, identify the role of the financial sector in the commodity chain of wind energy and find out why it comes to financialization processes in the German wind industry.

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Dealing with sea level rise on small Maledivian Islands

Arne Hennig
arne.hennig"AT"uni-hamburg.de 

Betreuung durch: Prof. Dr. Beate M. W. Ratter

Laufzeit: 2016-2019

Projektbeschreibung:

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Adaptability of social-ecological systems. Environmental knowledge, learning and governance on small islands from a complexity theory perspective. The Bahamas as a case study

Lars Bomhauer-Beins, M.Sc.
lars.bomhauer-beins"AT"uni-hamburg.de 

Betreuung durch: Prof. Dr. Beate M. W. Ratter

Laufzeit: 2015-2018

Projektbeschreibung:
Small islands can be perceived as complex social-ecological systems. Many Small Island Developing States (SIDS) face a number of global climate change risks which threaten a sustainable development process. Conceptually based on complexity theory and resilience perspective, the project’s objectives are to analyze how social agents respond to natural pressures and stressors, and how risk and environmental knowledge are produced, integrated and employed to strengthen adaptability and social-ecological resilience. For this purpose, it is necessary to examine knowledge exchange processes across various scales from global to local. Specifically, focus will be put on the interrelations of trans-local expert knowledge and local lay knowledge as well as on the role that hybrid forms of knowledge play in specific contexts. Furthermore, particular emphasis will be laid on the modes of communication and learning processes which influence an adaptive environmental and risk management. In a final step it is aimed to utilize the results for the improvement of adaptive and participatory modes of social-ecological systems governance.

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New Spaces for Climate Change - The Societal Construction of Landscapes in Times of a Changing Climate

Vera Köpsel, M.Sc.
vera.koepsel"AT"uni-hamburg.de 

Betreuung durch: Prof. Dr. Beate M. W. Ratter

Laufzeit: 2014-2017

Projektbeschreibung:
The impacts of climate change are likely to alter the appearance of many coastal landscapes, for example through extreme weather, flooding or increased cliff erosion. To the people living and working in affected places, such changing landscapes are not merely physical spaces, but places of everyday life, cultural heritage and personal attachments. The same holds true for the staff of organizations who shape the delivery of adaptation strategies on the ground. To understand the role different perceptions of landscapes play in climate change adaptation on the local level, this PhD project takes on a social-constructivist perspective by asking: How are landscapes and landscape changes subjectively constructed by different actors in environmental management? How do adaptation measures arise at the nexus of landscape, local debates, and regional identity? As an empirical case study serves the Godrevy headland in Cornwall (UK), a rural peninsula whose coastal landscapes and cultural heritage are central to its regional identity and economic activities. This thesis is based on the results of qualitative interviews with key persons involved in landscape and adaptive management in Cornwall and discusses the implications of contrasting landscape perceptions for climate change adaptation in rural coastal regions. 

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Enhancing Risk Management in Multi-Sektor-Stakeholder-Situations

Birgit Gerkensmeier
birgit.gerkensmeier"AT"hzg.de  

Betreuung durch: Prof. Dr. Beate M. W. Ratter

Laufzeit: 2014-2017

Projektbeschreibung:
Coastal regions, such as the PhD’s case study area of the trilateral (Dutch, German and Danish) Wadden Sea Region, are already vulnerable to environmental and societal risks and vulnerability is expected to increase in coming decades with encompassing new challenges such as demographic changes and conflicting uses of space, both on land and at sea. In the face of these challenges, increased scientific information and knowledge on its own seems to be insufficient to reach sustainability and effective risk management; on the contrary participatory activities are needed to facilitate integration of formal and informal knowledge as well as different interests and risk perceptions. Although scientific discussions encourage a shift from governmental top-down decision-making to broader, collaborative forms in risk management, there is, however, an increased demand on addressing its practical implementations.

In this spirit the PhD project hypothesize the demand of further rethinking risk management in a way that dealing with risk becomes a more societal endeavour marking a significant departure from the current dominant technical risk management paradigm. Aiming to contribute to develop and strengthen implementation of social processes in coastal risk management the PhD project focuses on the question what kind of structural improvement is necessary in order to enhance participatory processes in multi-stakeholder environments, how they can be targeted methodically, and which spatial dimension will represent an efficient level to implement enhanced participatory and negotiation processes in the cross-national Wadden Sea Region.

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Sustainable adaptation to climate change – exploring perceptions and adaptive capacity of agricultural smallholder groups in St Lucia (working title)

Franziska Wolf, B.A. int, BBA, MIBA
franziska.wolf"AT"haw-hamburg.de

Betreuung durch: Prof. Dr. Beate M. W. Ratter

Laufzeit: 2013-2018

Projektbeschreibung:
The present work investigates the prospects of sustainable community-based adaptation in a small island context. By means of an integrated framework, local adaptive capacity as a component of social vulnerability will be assessed. In particular, focus is given to assessing the adaptive capacity of vulnerable groups to climate variability and climate change. In line with the principles of action research with its typical iterative, cyclical learning dimensions, the present work thus utilizes vulnerability theory, complemented with insights from learning theories, to assess and explain the adaptive potential of distinctive vulnerable groups on small islands.

Operationally, the case study focuses on farmer and fishery producer groups in St Lucia, a Caribbean SIDS, and examines their adaptive capacity and resulting social vulnerability to a changing environment, attributable, at least partly, to climate variability and climate change. At the heart of this work is a qualitative investigation into how climate change and climate variability are perceived by these agents, how they receive, process and disseminate related information and knowledge, and the capacity-building they anticipate or may subsequently take.

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Fairer Handel in Zeiten globaler Vernetzung - Machtverschiebung in globalen Wertschöpfungsketten

Dipl. Geogr. Jutta Kister
Jutta.Kister"AT"uibk.ac.at

Betreuung durch: Prof. Dr. Martina Neuburger

Laufzeit: seit 2013

Projektbeschreibung:
Der Faire Handel hat sich in Europa in den vergangenen Jahren zu einem großen Wachstumsmarkt entwickelt und erfährt damit vor allem im Globalen Norden eine neue Dynamik. Die inhärenten Spannungen zwischen den sozialen Prinzipien und den Marktprinzipien, in denen sich der Faire Handel bewegen muss, verschärfen sich, je kommerziell erfolgreicher die fair gehandelten Produkte werden. Dies wirkt sich nicht allein auf die räumliche Verteilung von ökonomischen Tätigkeiten aus, sondern auch auf die Macht- und Steuerungsstrukturen in den Globalen Ketten.

Anhand des Fairen Handels in Deutschland werden die Ketten-Konfigurationen unterschiedlicher Produkte analysiert und in Typen untergliedert. Insbesondere die Beziehungen an der Schnittstelle zwischen produzierenden und aufkaufenden Akteuren sind Veränderungen unterlegen und essentiell für die vertiefte Analyse der Steuerungs- und Machtstrukturen. Darüber hinaus werden Näheverhältnisse in den Beziehungen zwischen Produzent und Konsument im Spannungsfeld von Kontrolle und solidarischem Empowerment der Produzenten diskutiert. Im Forschungsprojekt steht die Fokussierung komplexer Verflechtungen (alternativer) globaler Handelsbeziehungen und die Aushandlungen zwischen Wirtschaft und Gesellschaft im Mittelpunkt. Qualitative sozialwissenschaftliche Methoden und mehrere Analyseebenen entlang der Ketten unterstützen eine holistische Betrachtung alternativer globaler Wertschöpfungsketten.

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