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Rangelands are the most widespread land-use systems in drylands, where they often represent the only sustainable form of land-use due to the limited water availability. The intensity of the land-use of such rangeland ecosystems in drylands depends to a large extent on the climatic variability in time and space. Rangeland systems are seriously threatened by climate change, because climate change will alternate the availability of water in time and space. This dissertation therefore deals with the question which role climatic variability plays for the effects of grazing on vegetation in dry rangelands. The relatively intact steppes in central Mongolia were chosen as a model system. They are characterised by low precipitation and high climatic variability in the south (100mm annual precipitation), and comparatively high precipitation and low climatic variability in the north (250mm). The effects of grazing on vegetation on 15 grazing transects were investigated along the climatic gradient. The central elements were the plant species and their abundances on 10m x 10m areas, for which functional characteristics such as height, affiliation of functional groups or leaf nutrients were recorded. The main hypothesis of this dissertation is that grazing has a greater impact on vegetation communities with increasing rainfall. To test this hypothesis, three studies were carried out. In a first study, the research group found that the vegetation communities in the dry area differ strongly along the climatic gradient, while the plant communities in the wetter area differ more strongly along the grazing gradient. The results of the second study suggested that this difference can be explained by a functional environmental filter that becomes weaker from south to north as the niche spectrum increases. The third study has shown that this is likely a function of the higher availability of resources, which at the same time leads to higher grazing pressure, therewith stressing the vegetation especially in years with droughts. In summary, the author concludes that the climate gradient also represents an environmental filter that filters species for certain characteristics, thus having a significant influence on the vegetation. Climatic variability influences the effect of grazing on vegetation, which is particularly problematic where the grazing intensity is high and the species are less adapted to strong climatic fluctuations. Future scenarios predict increasing productivity and therefore increasing livestock density. This may lead to an increase in floristic and functional diversity across the climate gradient, but also to increasing grazing effects and therefore threads for overgrazing. Increasing climatic variability is likely to intensify this thread, especially in the moister regions, whereas the dry rangelands are likely to be more resilient due to the adaptation of the plants to non-equilibrium dynamics.
Food forests present a promising solution to address multiple sustainability challenges adaptable to local contexts. As biodiverse multi-strata agroforestry systems, they can provide several ecological, socio-cultural and economic services. They sequester carbon, limit soil erosion and regulate the micro-climate; they offer the opportunity for education on healthy diets and ecology, and they produce food and can create livelihood opportunities. However, despite their obvious benefits, food forests are still a niche concept. To date, research has focused on their ecological and social services; we lack an understanding of food forests as a comprehensive sustainability solution, including their economic dimension, and knowledge on how to develop them. Addressing these gaps, this qualitative research used a solution- and process-oriented methodology guided by transformational sustainability research. In a comparative case study approach, it created an inventory of 209 food forests, followed by interviews and site visits of 14 sites to understand their characteristics and assess their sustainability (Article 1). More indepth, it analyzed the implementation path of seven food forest for success factors, barriers and coping strategies (Article 2). Based on these insights, two experimental case studies were initiated to develop sustainable food forests with practice partners, one based in Phoenix, Arizona, U.S. and one in Lüneburg, Germany. Two studies analyzed the cases' outputs and processes highlighting success factors and challenges, including the role of a sustainable entrepreneurial ecosystem (Article 3, Phoenix case) and key features of productive partnerships to understand why one case succeeded and the other failed (Article 4). Findings include key features of existing and sustainable food forests as well as success factors on how to develop them; namely acquiring a complementary skill set that includes specialty farming and entrepreneurial know-how, securing sufficient start-up funds and long-term land access as well as overcoming regulatory restrictions. Supporting institutions are especially needed to integrate and professionalize the planning stage and provide know-how on alternative business practices. Key features of productive partnerships include an entrepreneurial attitude, access to support functions, long-term orientation and commitment to food system sustainability.
Collaborative governance is a promising approach to address the difficult challenges of sustainability through global public and private partnerships between diverse actors of state, market and civil society. The textile and clothing industry is an excellent example where a variety of such initiatives have evolved to address the wicked sustainability challenges. However, the question arises whether collaborative governance actually leads to transformation. In this dissertation, the author therefore questions whether and how collaborative governance in the textile sector provides space for, or pathways to, sustainability transformation. In three scientific articles and this framework paper, the author uses a mixed-methods research approach and follows scholars of sustainability science towards transformation research. First, he conducts a systematic literature review on inter-organizational and governance partnerships before diving into a critical case study on an interactive collaborative governance initiative, the German Partnership for Sustainable Textiles (Textiles Partnership). The multi-stakeholder initiative (MSIs) was initiated by the German government in 2015 and brings together more than 130 organizations and companies from seven stakeholder groups. It aims at improving working conditions and reducing environmental impacts in global textile and clothing supply chains. In two empirical articles, the author then explores learning spaces in the partnership and the ways in which governance actors navigate the complex governance landscape. For the former, he uses a quantitative and qualitative social network analysis based on annual reports and qualitative interviews with diverse actors from the partnership. Then, he uses qualitative content analysis of the interviews, policy documents and conducts a focus group discussion to validate assumptions about the broader empirical governance landscape and the social interactions within. Finally, in this framework paper, he uses theories of transformation to distinguish forms of change and personal, political and practical spheres of transformation, and reflects on the findings of the three articles in this cumulative dissertation.
Im Projekt "Nawi-In" (Naturwissenschaftlichen Unterricht inklusiv gestalten) wurde die Entwicklung professioneller Kompetenzen für den inklusiven naturwissenschaftlichen Unterricht von Lehramtsstudierenden der Primar- und Sekundarstufe beforscht. Dabei wurden Lehramtsstudierende des naturwissenschaftlichen Primar- und Sekundarstufenunterrichts über drei Semester im Projektbandseminar begleitet. Als Teilprojekt des Projekts "Nawi-In" setzt diese Arbeit den Schwerpunkt auf drei Fokusse: die Entwicklung des Kategoriensystems inklusiver naturwissenschaftlicher Unterricht (KinU), die Beforschung der professionellen Handlungskompetenz sowie der professionellen Wahrnehmung bezüglich inklusiven naturwissenschaftlichen Unterrichts. Im ersten Fokus geht es sowohl um die Entwicklung und Validierung des KinUs als auch um die Überprüfung der Gütekriterien des KinUs. Zunächst wurden die Charakteristika inklusiven naturwissenschaftlichen Unterrichts, die die Kategorien des KinUs 1.0 darstellen, in einem systematischen Review aus der Literatur induktiv abgeleitet. Die Kategorien (n=935) verteilten sich auf insgesamt vier Abstraktionsebenen von der allgemeinen Hauptkategorienebene über die Subkategorien-, Code- bis hin zur konkreten Subcode-Ebene des KinUs. Während zunächst n=16 Kategorien die Verbindung naturwissenschaftlicher Charakteristika mit der inklusiven Umsetzung auf der Hauptkategorien-Ebene gebildet haben, waren es nach der Weiterentwicklung und Überarbeitung des KinUs 2.0 n=15 Hauptkategorien. Die Weiterentwicklung des KinUs fand mithilfe der Validierung durch Datentriangulation statt. Durch die Anwendung des KinUs auf Video- und transkribierte Audiodaten wurden fortlaufend weitere Kategorien induktiv abgeleitet. Zudem wurde die Struktur des KinUs vereinfacht, sodass die inklusiven Zugänge zu jedem naturwissenschaftlichen Charakteristikum bis zur Code-Ebene als ein gleichbleibendes Muster abgebildet werden können. Der zweite Fokus bezieht sich auf die Entwicklung und Beforschung der professionellen Handlungskompetenz der Lehramtsstudierenden bezüglich inklusiven naturwissenschaftlichen Unterrichts. Dabei wurde analysiert, welche inklusiv naturwissenschaftlichen Charakteristika Lehramtsstudierende in ihrem Unterricht implementieren, wie sich ihre professionelle Handlungskompetenz während der Praxisphase entwickelt sowie welche Unterschiede und Gemeinsamkeiten sich für die Primar- und Sekundarstufen bezüglich ihrer professionellen Handlungskompetenz ergeben. Dafür wurden die Unterrichtsvideos, die die Studierenden während der Praxisphase jeweils zweimal von ihrem eigenen Unterricht angefertigt haben, mit dem KinU qualitativ inhaltlich analysiert. Insgesamt haben die Studierenden zwar unterschiedliche Zugänge auf der Subkategorien-Ebene zum naturwissenschaftlichen Unterricht implementiert, allerdings haben sie den Schülern innerhalb dieser Zugänge nur selten verschiedene Optionen geboten. Im Vergleich der Schulstufen zeigt sich, dass sich die zunehmende Fachlichkeit von der Primar- zur Sekundarstufe widerspiegelt. Insgesamt haben die Studierenden von dem ersten zum zweiten Unterrichtsvideo zunehmend mehr inklusiv naturwissenschaftliche Charakteristika in ihren Unterricht implementiert. Im dritten Fokus wurde die professionelle Wahrnehmung von Lehramtsstudierenden bezüglich inklusiven naturwissenschaftlichen Unterrichts beforscht. Dabei wurde analysiert, welche inklusiv naturwissenschaftlichen Charakteristika Lehramtsstudierende wahrnehmen, wie sich ihre professionelle Wahrnehmung entwickelt sowie welche Unterschiede und Gemeinsamkeiten sich für die Primar- und Sekundarstufe bzgl. ihrer professionellen Wahrnehmung ergeben. Dafür wurden video-stimulierte Reflexionen durchgeführt, wobei die Studierenden Videoszenen bzgl. inklusiven naturwissenschaftlichen Unterrichts beschreiben, interpretieren sowie Handlungsalternativen generieren sollten. Bei den Video-Stimulated Reflections (VSRef) haben die Studierenden eine Videovignette aus einem Sachunterricht zum Thema Löslichkeit reflektiert. Die VSRefs wurden zu drei Zeitpunkten durchgeführt: vor dem ersten Mastersemester und vor sowie nach der Praxisphase im zweiten Mastersemester. Zudem wurden während der Praxisphase jeweils zweimal mit allen Studierenden Video-Stimulated Recalls (VSR) durchgeführt. Dabei haben die Studierenden Ausschnitte ihrer eigenen Unterrichtsvideos reflektiert. Sowohl die VSRef als auch die VSR wurden transkribiert und mit dem KinU qualitativ inhaltlich analysiert. Die Lehramtsstudierenden haben zunehmend mehr inklusiv naturwissenschaftliche Charakteristika in den eigenen und fremden Unterrichtsvideos wahrgenommen. Zwischen den Schulstufen waren nur geringe Unterschiede zu erkennen. Am häufigsten haben die Studierenden Zugänge zur inklusiven Gestaltung der Anwendung naturwissenschaftlicher Untersuchungsmethoden wahrgenommen. Insgesamt zeigt sich, dass die Lehramtsstudierenden ihre professionellen Kompetenzen bzgl. inklusiven naturwissenschaftlichen Unterrichts weiterentwickeln konnten. Zudem wurde mit der Entwicklung des KinUs ein Kategoriensystem zur Beforschung und ein Unterstützungsraster für Lehrkräfte zur Gestaltung inklusiven naturwissenschaftlichen Unterrichts geschaffen.
Nachhaltigkeitsziele im Sinne einer Ökologie, Ökonomie und Soziokultur lassen sich im Bauwesen auf verschiedene Instrumente zurückführen. Optimierung des Wärmeschutzes durch die Energieeinsparverordnung (Effizienz) oder Minimierung von Abfall im Kreislaufwirtschaftsgesetz (Suffizienz). Um jedoch eine neue Qualität der Nachhaltigkeit zu schaffen, ist ein Paradigmenwechsel notwendig. Dabei können Cradle to Cradle Prinzipien als ökoeffektive Methode angewandt werden, in dem exemplarisch die Biodiversität eingebunden, gesunde Bauprodukte verbaut und erneuerbare Energien genutzt werden. Die Natur dient als Vorbild (Konsistenz). Demnach werden Gebäude nützlich für Mensch, Umwelt und Gesellschaft umgesetzt und gleichzeitig Werte geschaffen. Für den deutschen Einzelhandel bestehen vielschichtige Potenziale, da der Gebäudebestand mit mehreren Millionen Quadratmetern bedeutend ist und die Bauwerke aufgrund von Konzeptänderungen oder Verschleiß der Ladenflächen regelmäßig umgebaut werden. Die Forschung beginnt mit einer Bestandsaufnahme von Cradle to Cradle Bauprodukten und Analyse eines real umgesetzten Einkaufszentrums. Um Einflussfaktoren von Stakeholdern zu identifizieren, wurden qualitative Experteninterviews mit ausgewählten Projektbeteiligten aus Bauherrn, Betreibern, Beratern, Mietparteien und Herstellern durchgeführt. Im Rahmen des Forschungsvorhabens wurde untersucht, inwieweit sich Bauprodukte aus der Gebäudeplanung in wissenschaftlicher Theorie und praktischer Bauwirtschaft umsetzen lassen, Geschäftsmodelle anwendbar sind, Trends und Innovationen im Zusammenhang stehen oder Änderungen in Politik oder Wirtschaft notwendig sind. Im Ergebnis wurden Maßnahmen für eine neue Qualität der Nachhaltigkeit bei Einzelhandelsgebäuden identifiziert. Exemplarisch wird anhand der Interviews deutlich, dass neben einem staatlichen Umweltzeichen oder einer Green Building Planungsdisziplin, insbesondere die Ökonomie in Form von Investitions- und Betriebskosten den größten Stellenwert besitzt. Es braucht einen staatlichen Regulierungsrahmen und neue Geschäftsmodelle, damit nachhaltige Bauprodukte wirtschaftlich werden und durch Stakeholder in den Prozessen der Planung, Bauausführung und dem Betrieb berücksichtigt werden.
Undertaking local actions, such as implementing public (sustainability) policy, plays a crucial role in achieving sustainable development (SD) at the municipal level. In this regard, indicator-based assessment supports effective implementation by measuring the SD process, based upon evidence-based outcomes that indicators produce. Over the last decade, using subjective indicators, which rely on an individual's self-perception to measure subjects, has gained its significance in sustainability assessment, in line with the increasing importance of signifying individual's and community's well-being (WB) in the context of SD. This study aims to discuss and clarify the scope and functions of subjective sustainable development indicators (SDIs) conceptually and theoretically while examining the usability of such indicators employed in the practice of assessing sustainability policy and action process in a Japanese municipality. Furthermore, the potential usability of using subjective SDIs in monitoring a municipal initiative of the United Nations’ Sustainable Development Goals (SDGs) is also explanatorily examined. The present paper consists of a framework paper and three individual studies. In the framework paper, Section 1 introduces the global transition of SD discourse and the role that local authorities and implementing public policy play in achieving SD while outlining how WB positions in the SD context. Section 2 provides a brief overview of the major scope of overall SDIs at the conceptual and theoretical levels. Section 3 defines WB in the study's own right while exploring the scope of indicators measuring WB. In addition, this study strives to further clarify the peculiar scope of SDIs, measuring WB by synthesising the findings. Section 4 overviews how SD at the municipal level in Japan is practiced while acknowledging the extent to which residents perceive WB and SDGs in policymaking. Section 5 provides a brief yet extensive summary of the three individual studies. Section 6 discusses the findings while presenting implications for further study and practices of subjective SDIs. Furthermore, the three individual studies provide a thorough and in-depth discussion of the study subject. Study 1 illustrates the SD trend at the municipal level in Japan and the growing recognition of using subjective SDIs in public (sustainability) policy assessment in exploring comparative SDI systems to municipality groups. The findings, in turn, raise the need for a further study on subjective SDIs. Study 2 extensively discusses the concept of WB as the overarching subject to be measured while examining varying approaches and scopes of SDIs. It identifies three differentiated WB (i.e., material and social objective WB as well as subjective WB) and distinctive approaches of subjective SDIs (i.e., expert-led and citizen-based approaches) alongside objective SDIs. The findings suggest that these SDIs identified are, conceptually, most capable of measuring associated WB; for instance, citizen-based subjective SDIs can most optimally measure subjective WB. Finally, Study 3 examines the usability of (citizen-based) subjective SDIs in a practice of assessing public policy, aiming at municipal SD, and the potential usability of using such indicators in monitoring a municipal SDG initiative. The findings highlight the determinants and obstacles of using subjective SDIs as well as signifying WB in measuring progress of a municipal SD practice.
Companies increasingly use social and environmental accounting and reporting (SEAR) to measure, manage, and report their influence on ecological and social issues, i.e., climate change and human rights violations. Nowadays, there are many different tools, frameworks, and standards for SEAR that companies can use. Beyond the content presented in the tool itself, e.g., social and/or ecological information, these tools differ, among others, by the language used and the type of data collected (e.g., qualitative, quantitative, or monetary data). This dissertation aims to expand previous literature by clarifying the effects of SEAR on corporate decision-making and its influencing factors. Additionally, antecedents for implementation and use of SEAR in regard to supporting sustainability decision-making are discussed. For this purpose, the given dissertation investigates public sustainability reports by companies with different environmental orientation, conducts two survey-based case studies on the effects of different types of SEAR and one qualitative case study on the antecedents of institutionalizing management accounting change through SEAR. The results lead to seven criteria that practitioners and researchers should recognize for supporting successful SEAR regarding a company's environmental orientation, the role of employees and leadership as well as the specific SEAR tool itself.
Urban areas are prone to climate change impacts. Simultaneously the world's population increasingly resides in cities. In this light, there is a growing need to equip urban decision makers with evidence-based climate information tailored to their specific context to adequately adapt to and prepare for future climate change. To construct climate information high-resolution regional climate models and their projections are pivotal. There is a need to move beyond commonly investigated variables, such as temperature and precipitation, to cover a wider breath of possible climate impacts. In this light, the research presented in this thesis is centered around enhancing the understanding about regional-to-local climate change in Berlin and its surroundings, with a focus on humidity. More specifically, following a regional climate modelling and data analysis approach, this research aims to understand the potential of regional climate models, and the possible added value of convection-permitting simulations, to support the development of high-quality climate information for urban regions, to support knowledge-based decision-making. The first part of the thesis investigates what can already be understood with available regional climate model simulations about future climate change in Berlin and its surroundings, particularly with respect to humidity and related variables. Ten EURO-CORDEX model combinations are analyzed, for the RCP8.5 emission scenario during the time period 1970-2100, for the Berlin region. The results are the first to show an urban-rural humidity contrast under a changing climate, simulated by the EURO-CORDEX ensemble, of around 6% relative humidity, and a robust enlarging urban drying effect, of approximately 2-4% relative humidity, in Berlin compared to its surroundings throughout the 21st century. The second part explores how crossing spatial scales from 12.5km to 3km model grid size affects unprecedented humidity extremes and related variables under future climate conditions for Berlin and its surroundings. Based on the unique HAPPI regional climate model dataset, two unprecedented humidity extremes are identified happening under 1.5°C and 2°C global mean warming, respectively SH>0.02 kg/kg and RH<30%. Employing a double-nesting approach, specifically designed for this study, the two humidity extremes are downscaled to the 12.5km grid resolution with the regional climate model REMO, and thereafter to the 3km with the convection-permitting model version of REMO (REMO NH). The findings indicate that the convection-permitting scale mitigates the SH>0.02kg/kg moist extreme and intensifies the RH<30% dry extreme. The multi-variate process analysis shows that the more profound urban drying effect on the convection-permitting resolution is mainly due to better resolving the physical processes related to the land surface scheme and land-atmosphere interactions on the 3km compared to the 12.5km grid resolution. The results demonstrate the added value of the convection-permitting resolution to simulate future humidity extremes in the urban-rural context. The third part of the research investigates the added value of convection-permitting models to simulate humidity related meteorological conditions driving specific climate change impacts, for the Berlin region. Three novel humidity related impact cases are defined for this research: influenza spread and survival; ragweed pollen dispersion; and in-door mold growth. Simulations by the regional climate model REMO are analyzed for the near future (2041-2050) under emission scenario RCP8.5, on the 12.5km and 3km grid resolution. The findings show that the change signal reverses on the convection-permitting resolution for the impact cases pollen, and mold (positive and negative). For influenza, the convection-permitting resolution intensifies the decrease of influenza days under climate change. Longer periods of consecutive influenza and mold days are projected under near-term climate change. The results show the potential of convection-permitting simulations to generate improved information about climate change impacts in urban regions to support decision makers. Generally, all results show an urban drying effect in Berlin compared to its surroundings for relative and specific humidity under climate change, respectively for the urban-rural contrast throughout the 21st century, for the downscaled future extreme conditions, and for the three humidity related impact cases. Added value for the convection-permitting resolution is found to simulate humidity extremes and the meteorological conditions driving the three impacts cases.
Design methods for collaborative knowledge production in inter- and transdisciplinary research
(2022)
This dissertation seeks to better understand how design methods facilitate collaborative knowledge production and integration in inter- and transdisciplinary sustainability research. Through five independent papers, this dissertation contributes to addressing the research question on four levels – conceptual-epistemological, empirical, methodological and practical. By exploring the linkages between design research and inter- and transdisciplinary research, a conceptual basis for the targeted use of design methods in collaborative processes of inter- and transdisciplinary research is laid and their spectrum of methods is expanded. This is followed by the development of a transformative epistemology in and for problem-oriented, collaborative forms of research, such as transdisciplinary sustainability research, called problematic designing. Based on a deeper understanding of integration and collaborative knowledge production, as well as its accompanying challenges, empirical research into applying design prototyping as a method in and for situations of collaborative research was conducted. To this end, the findings provide a fundamental basis for the facilitation of inter- and transdisciplinary research processes when dealing with complex problems. With its inherent openness and iterative approach in addressing the unknowns of complex phenomena, design prototyping contributes to the required form of imagination that enables to anticipate possible futures. Furthermore, by including visual-haptic modes of expression, design prototyping reduces the dominance of language and text in scientific negotiation processes and does justice to the diversity of cognitive modes. Finally, the empirical findings of this dissertation emphasise the importance of the visual-haptic dimension for collaborative knowledge production and the communication of knowledge, and provide insights into the visual structuring of human thought processes. The results on material metaphors, collaborative prototyping and material-metaphorical imagery contribute decisively to the basic knowledge of the epistemological quality of design and the importance of the visual and haptic for thought processes in general. The extension and adaptation of existing analysis methods in this dissertation add to the further development of analysis of visual-haptic data. The results are once again reflected in the synthesis of this framework paper as cross-cutting issues.
The transition of our energy system towards a generation by renewables, and the corresponding developments of wind power technology enlarge the requirements that must be met by a wind turbine control scheme. Within this thesis, the role of modern, model-based control approaches in providing an answer to present and future challenges faced by wind energy conversion systems is discussed. While many different control loops shape the power system in general, and the energy conversion process from the wind to the electrical grid specifically, this work addresses the problem of power output regulation of an individual turbine. To this end, the considered control task focuses on the operation of the turbine on the nonlinear power conversion curve, which is dictated by the aerodynamic interaction of the wind turbine structure and the current inflow. To enable a power tracking functionality, and thereby account for requirements of the electrical grid instead of operating the turbine at maximum efficiency constantly, an extended operational range is explicitly considered in the implemented control scheme. This allows for an adjustment of the produced power depending on the current state of the electrical grid and is one component in constructing a reliable and stable power system based on renewable generation. To account for the nonlinear dynamics involved, a linear matrix inequalities approach to control based on Takagi-Sugeno modeling is investigated. This structure is capable of integrating several degrees of freedom into an automated control design, where, additionally to stability, performance constraints are integrated into the design to account for the sensitive dynamical behavior of turbines in operation and the loading experienced by the turbine components. For this purpose, a disturbance observer is designed that provides an estimate of the current effective wind speed from the evolution of the measurements. This information is used to adjust the control scheme to the varying operating points and dynamics. Using this controller, a detailed simulation study is performed that illustrates the experienced loading of the turbine structure due to a dynamic variation of the power output. It is found that a dedicated controller allows wind turbines to provide such functionality. Additionally to the conducted simulations, the control scheme is validated experimentally. For this purpose, a fully controllable wind turbine is operated in a wind tunnel setup that is capable of generating reproducible wind conditions, including turbulence, in a wide operational range. This allows for an assessment of the power tracking performance enforced by the controller and analysis of the wind speed estimation error with the uncertainties present in the physical application. The controller showed to operate the turbine smoothly in all considered operating scenarios, while the implementation in the real-time environment revealed no limitations in the application of the approach within the experiments. Hence, the high flexibility in adjusting the turbine operating trajectories and structural design characteristics within the model-based design allows for efficient controller synthesis for wind turbines with increasing functionality and complexity.