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This dissertation deals with the increasingly recognized role of incumbent firms in advancing sustainability-oriented industry transitions. Incumbent firms are understood as firms-in-industries, which are embedded in established market structures and thereby contrast new entrant firms. The purpose of this research is twofold. First, to provide empirical evidence of barriers to and success factors of incumbent-driven industry transitions. Second, to unify hitherto dispersed descriptions of transition-related firm behaviour in a new understanding of incumbent firms in industry transitions. To this end, theoretical concepts are discussed and extended on the basis of different empirical studies in the German meat industry. The meat industry serves as suitable research setting due to its diverse sustainability challenges, ranging from climate change and pollution to animal welfare and public health, as well as its current developments towards sustainable protein alternatives. The meat context also offers opportunities to delve into individual-level processes influencing transition-related behaviour. The main contribution of this dissertation is a Multi Embeddedness Framework (MEF) that details processes and outcomes of integrated incumbent firm behaviour, including passive, reactive and proactive behaviors. The framework acknowledges the diversity in incumbent firm behaviors within industries and firms and provides new insights into transition-related behaviors at firm and individual level. With regard to the latter, the potential of learning about and from innovative start-up firms as well as shared sensemaking processes are discussed. The contents of this dissertation provide valuable contributions to the transition literature as well as important management implications with regard to the stimulation and promotion of proactive behaviors
The Sustainable Development Goals (SDGs) recognize the importance of the inextricable link between social and ecological systems and human quality of life (QoL) and biodiversity. Therefore, understanding the feedback and interactions between biodiversity, nature’s contributions to people (NCP), and QoL plays a central role in advancing toward sustainability. In this context, the social-ecological systems (SES) approach has advanced on the subject, particularly in recent decades; however, much remains to be done to comprehensively understand these relationships and interactions, especially at local decision-making scales. In this thesis, through the lenses of the SES approach, the researcher investigates connections between biodiversity, NCP, and QoL in a tropical dry forest (TDF) on the Western coast of Mexico. This place is one of the best-known Neotropical TDF and has been the focus of SES research in the past 20 years, making it an excellent case study for exploring these connections. First, to approach the need for dialogue among different global and local scales and between global and local frameworks, the thesis identifies five key components of the SES dynamics-(1) ecological supply, (2) co-production of NCP, (3) management, (4) demand, and (5) benefits - and three local decision-making scales of analysis: individual plot, smallholder, and land tenure or governance units. A literature review was performed on the social-ecological indicators for the last 11 years in the Chamela-Cuixmala region to operationalize this framework. Second, this thesis uses social-ecological information to identify social-ecological systems units (SESU) spatially explicitly. A methodology was provided to spatially identify the components of social-ecological systems that environmental conditions and management practices have shaped at three previously stated relevant decision-making scales: plots owned by individuals, plot owners, and governance units. To do so, the research group identified and characterized: (1) ecological clusters (EC), (2) social-management clusters (SC), and (3) SESU in a TDF in western Mexico. The findings suggested that decision-makers (ejidatarios, i.e., type of ownership (related to agrarian reform), that in most cases the land allocated is small-smallholders) are bounded by the topographical characteristics and the public policies that determine communal (or private) governance and the number of resources available to them. Finally, the thesis examines the self-perceived QoL across the different SESU, finding 48 QoL items, which were grouped into six categories: 1) social capital, 2) economic capital, 3) agency, 4) nature, 5) peasant non-work activities, and 6) government and services; and two additional dimensions referred to obstacles and enablers of QoL. The researchers found that the more land cover transformation, the more enablers, and obstacles of QoL are identified; emphasis was put on economic capital to achieve QoL. As management is intensified and governance fosters individualism across SES, the higher the Current Welfare Index, and the lower the self-perceived material and non-material satisfaction.
Environmental governance beyond borders: Governing telecoupled systems towards sustainability
(2023)
This doctoral dissertation analyses the environmental governance of long-distance social-ecological interactions in telecoupled systems in two issue domains: global commodity chains and infrastructure projects as part of China’s Belt and Road Initiative (BRI). Although both domains involve different governance actors, institutions and processes, they both concern the question of how the involved actors develop governance structures and institutional responses to telecoupling. This dissertation aims to contribute to a deeper understanding of how to govern environmental problems that are associated with global flows. Since many multilateral environmental governance initiatives have not yet produced the desired solutions to global problems, particular attention is directed at unilateral state-led governance approaches. This dissertation addresses the questions of (1) how to achieve a spatial fit between the scale of telecoupled systems and the scale of governance institutions, (2) how governance actors exercise agency in governing telecoupled systems, and (3) how state actors can govern the domestic and foreign environmental effects of telecoupled flows. The results show that creating a spatial fit in the governance of global commodity flows is challenging because boundary and resolution mismatches can emerge. Boundary mismatches denote situations where social-ecological problems transcend established jurisdictional boundaries, whereas resolution mismatches refer to governance institutions that have too coarse a spatial resolution to allow them to address the specific aspects of social-ecological problems effectively. No single governance institution is likely to avoid all mismatches, which highlights the need to align multiple governance approaches to effectively govern telecoupled systems.
This dissertation evaluated the efficacy of three different internet-based interventions that can be regarded as indirect interventions to reduce depression since they primarily targeted risk factors for depression. For this purpose three registered randomized controlled trials were conducted. In addition to assessing the efficacy of the interventions regarding the primary outcomes, the efficacy to reduce depression and further secondary outcomes was studied. In Study I (N=200) the efficacy of an internet-based stress management intervention (iSMI), which was adapted and tailored to career starting teachers, was compared to a waitlist control group (WLG). The participants of the intervention group (IG) reported significant reductions on the primary outcome perceived stress at post-intervention (T2) and three month follow-up (3-MFU). Furthermore, it was shown that the intervention indirectly also reduced depression at T2 and 3-MFU. The effects were sustained at an extended 6-MFU. Besides efficacy, the feasibility to complement the iSMI with a newly developed internet-based classroom management training was shown. Moreover, mediation analyses corroborated the role of problem- and emotion-focused coping skills in the intervention's effect on stress and the indirect effect of the intervention on depression through stress. Study II (N=262) demonstrated the efficacy of an internet- and app-based gratitude intervention on the reduction of primary assessed repetitive negative thoughts at T2 and 3-MFU, as compared to a WLG. The participants of the IG also reported significantly reduced depressive symptoms at T2, and 3-MFU, with significant clinically meaningful effects. The effects were sustained at an extended 6-MFU. Besides efficacy, mediation analyses showed that repetitive negative thinking mediated the gratitude intervention's effect on depression. Finally, Study III N(=351) showed that an internet-based intervention, tackling worries at the beginning of the COVID-19 pandemic, was effective as compared to an active mental health advice group. At T2, two weeks after randomization, the IG reported significantly reduced levels on the primary outcome worry as compared to controls. Participants of the IG also reported significantly reduced levels of depression at T2, with significant clinically meaningful reductions. The extended follow-ups in the IG indicated that the improvements from baseline were sustained until the 2-MFU and the 6-MFU. In a mediation analysis, worry was shown to mediate the intervention's effect on depression. Across all three studies a reliable deterioration of depression was occasionally observed. In summary, the studies in this dissertation demonstrated the efficacy of various indirect interventions focusing on rather common psychological problems to indirectly reduce depressive symptoms. The extent to which depression severity could be reduced is comparable to reductions found within participants with comparable baseline depression severity, in internet-based interventions directly addressing depressive symptoms. Indirect interventions are suggested to increase the uptake of interventions that reduce depressive symptoms, since they might be perceived as less stigmatizing and might broaden the range of interventions to choose from.
The research described in this dissertation focuses on developing a process to remove oligomers and suppress their formation by intercepting the aging procedure's precursors using adsorbents when biodiesel and its blends are used as fuel. So far, there has been no attempt to cause the stabilization of biodiesel and its blends using adsorbents from open literature. This investigation is one of the first studies on the use of adsorbents to mitigate biodiesel and diesel fuel's stability behavior–biodiesel blends and the removal of oligomers or suppressing the formation of high molecular mass species in aging oil. This study's primary aim has been achieved by several experimental measurements that provided results on adsorbents' effecton fuel oxidative stability, especially ester-based fuel like biodiesel and its blends. The chemical composition and some critical rheological analyses of the samples have been measured to understand their role in the oxidation of the sample by comparing the presence and absence of the adsorbents during the aging process. Furthermore, it aims to use adsorbents to suppress oligomers' formation and remove them in aging oil due to the influence of biodiesel and its blends. The research project also seeks to stabilize fuel, especially ester-based fuel like biodiesel, and its blends using the adsorbents. The adsorbents' application will enhance biodiesel's oxidative stability and its blends during long-term storage or application, focusing on its use in plug-in hybrid vehicles, emergency power plants,and generators. The combustion engine only starts in plug-in hybrid vehicles if the battery cannot supply energy on longer journeys. As a result, the fuel remains longer in plug-in hybrid vehicles. Fuels that are exposed to heat and oxygen over anextendedperiod can form aging products. These aging products lead to the formation of deposits, especially in the case of diesel fuels mixed with biodiesel content,and can, therefore, endanger the operational safety of the vehicle in critical components such as injectors or filter units.
This thesis aims to contribute to a better understanding of the actual implementation of transdisciplinary research in sustainability science. Following three aims, this work likes to (1) contribute to the measurability of transdisciplinary research processes as well as their societal and academic outputs and impacts, to (2) demarcate transdisciplinary research from other modes of research in sustainability science and to (3) identify and examine the determinants that shape the contribution of transdisciplinary research to societal action for sustainable development and to scientific knowledge production. To serve these aims a mixed methods approach is applied that combines strong quantitative elements with in-depth qualitative analyses that integrate the perspectives of practitioners. This thesis provides a broad set of indicators to describe and assess transdisciplinary research that translate theoretical concepts form transdisciplinarity theory into observable variables. The indicators offer a holistic perspective on transdisciplinary research by representing research mode characteristics, societal as well as scientific outcomes of research projects and their specific context. To theoretically demarcate transdisciplinary research from other forms of research, a narrative literature review first elaborates the differences between "normal science", political use of scientific knowledge and transdisciplinarity in their underlying logics of problem definition, knowledge production and research utilization. Subsequently, these concepts were compared with perspectives and expectations of practitioners in the forest sector on integrative research settings. Moreover, a cluster analysis of data from 59 research projects identified five research modes that empirically demarcate ideal-typical transdisciplinary research from other research modes within sustainability science: (1) purely academic research, (2) practice consultation, (3) selective practitioner involvement, (4) ideal-typical transdisciplinary research and (5) practice-oriented research. Based on this finding, transdisciplinary research can be characterized as an intensive, but balanced involvement of practitioners. It incorporates not only the needs and goals of the practitioners but also their norms and values. Ideal-typical transdisciplinary research goes beyond mere consultatory research approaches and must be distinguished from what is conceptualized as applied research. Regression analysis of 81 research projects and statistical group comparisons of the five research mode clusters show that societal and academic outputs and impacts vary with specific project characteristics and combinations of project characteristics defined as research modes. The findings indicate that more interactive research modes reach more societal impacts. In particular, the involvement of practitioners in early project phases and the targeted dissemination of the research results positively affect societal impacts. This finding also aligns with practitioner expectations on integrative research and research utilization, provided by qualitative analysis. Moreover, the quantitative results show that scientific outputs and impacts decrease with the intensity of interactions, indicating a trade-off between societal and scientific outcomes and impacts. Overall, the empirical results of this thesis support the claimed effectiveness of transdisciplinary research in providing societally relevant, applicable knowledge and encourage further funding of transdisciplinary research by funding agencies.
This dissertation contributes to research on generating actionable knowledge for coastal governance to enhance the resilience of coastal social-ecological systems (SES) to climate change. It does this by providing theoretical, methodological and empirical insights on three research questions (RQs). These are: (1) what is a more actionable concept for applying the concept of resilience in coastal governance?; (2) what methods and approaches are suitable to generate actionable knowledge for coastal governance?; (3) what obstacles to knowledge co-production exist for early-career researchers (ECRs) and how can they be overcome? The RQs are addressed in five publications. For answering RQ1, the dissertation applies a research synthesis to bring together common themes and challenges documented in resilience, climate change and environmental governance literature. For answering RQ2, different methods and approaches for generating actionable knowledge are proposed and tested using a case-study in the SES of Algoa Bay, South Africa. These include (i) the analysis of stakeholder agency; (ii) the application of a stakeholder analysis; and (iii) the combination of a capital approach framework, and fuzzy cognitive mapping. Finally, for answering RQ3, the thesis provides a perspective on the obstacles that especially ECRs face, and actions that are needed to create the conditions under which knowledge co-production processes can be successful. This is done by applying a multi-method approach combining an online survey and workshop targeted at ECRs in the marine sciences. Key findings suggest that system and transformative knowledge are particularly important when applying the concept of resilience in coastal governance to generate actionable knowledge. The different methods and approaches that are proposed and tested contribute to generating both system and transformative knowledge. Firstly, they provide an overview of the capacities of different stakeholders to act, shed light on current collaboration and knowledge exchange, and enable the identification of different governance processes for coastal governance and climate change adaptation (system knowledge). Secondly, results have implications for how to improve knowledge exchange and identify leverage points that can enhance overall governance performance, thus providing recommendations on actions and processes that can enhance climate resilience in the case-study area (transformative knowledge). It is also highlighted how knowledge co-production can contribute to generating system and transformative knowledge together with stakeholders, and what actions are needed to build the capacities to translate knowledge into action. Additionally, the findings of this dissertation put forward actions that are needed at different organisational levels of the academic system to facilitate knowledge co-production processes with stakeholders involved in coastal governance. The results of this dissertation have implications for stakeholders and decision-making in the case-study area, as well as for environmental governance, climate change adaptation and broader sustainability research. Implications for stakeholders include recommendations for implementing formal commitments to share climate information across levels and sectors, establishing the role of information providers in the municipality, and reinforcing human capital within the local municipality in Algoa Bay. Findings also suggest the need for a more integrated approach to climate change adaptation in coastal planning and management frameworks. It also suggests that the conservation of environmental assets presents an important bottleneck for resilience management and needs to be further prioritised within decision-making. Implications for research include the applicability of methods beyond the context of this dissertation; a more actionable concept for approaching resilience in (coastal) governance systems; and a more critical reflection on how transformative research is conducted, and what academic foundation is needed so that it can fulfil its societal goal.
The food and land use system is one of the most important global economic sectors. At the same time, today's resource-intensive agricultural practices and the profit orientation in the food value chain lead to a loss of biological diversity and ecosystem services, high emissions, and social inequality - so-called negative externalities. From a scientific perspective, there is a broad consensus on the need to transform the current food system. This paper investigates the suitability of True Cost Accounting (TCA) as an approach to inte-grating positive and negative externalities into business decisions in the food and land use system, focusing on the retail sector due to its high market power and resulting influence on externalities along the entire food value chain. For this purpose, a qualitative study was con-ducted with sustainability managers of leading European food retail companies in terms of their annual turnover, sustainable finance experts, and political actors related to environmental and social policy. A sample of N=11 participants was interviewed about the emergence and meas-urement of externalities along the food value chain, the current and future relevance of knowing about externalities for food retail companies, and the market and policy framework necessary for the application of TCA. The data collected was evaluated using the method of qualitative content analysis according to Mayring. Findings show that TCA is a suitable method for capturing positive and negative external ef-fects along the food value chain and thus also for meeting the growing social, political, and financial demands for its sustainable orientation. At the same time, there are still some chal-lenges in the application of TCA, both from a theoretical and a practical point of view. The main challenges at present are the lack of a standardised methodology, data availability, and key performance indicators. Due to the focus on prices, margins and competitors, food retail groups, in particular, emphasise the risk of revenue and profit losses as well as customer churn when applying TCA. Hence, the introduction of TCA in the food and land use system requires the development of measures that are socially acceptable, backed by legal frameworks and promote the scientific development of the methodology. This offers the opportunity to create a level playing field, apply the polluter-pays principle to the entire value chain and support science in developing appropriate indicators as well as a TCA database. Food retail companies can benefit from addressing TCA at an early stage by analysing their value chain to initiate change processes early, identify risk raw materials and products, reduce negative externalities through targeted measures, sensitise customers to the issue and thus differentiate themselves from competitors.
Contemporary society is shaped by the idea that time is, above all, a scarce economic resource that must be used efficiently. Increasingly, however, scientific findings suggest that such a way of perceiving of time seems a major cause of the current global climate and sustainability crisis. Considerably less research work has been carried out in relation to the role of individual time-related needs regarding unsustainable consumption behaviour, although consumer research has been addressing needs-oriented approaches to sustainable consumption for a long time. Environmental and Sustainability Education (ESE) is considered an essential strategy to achieve the global sustainability goals of Agenda 2030. Internationally, as well as on a national level, ESE is increasingly mainstreamed in educational curricula and practice. Given the relation between time, needs and sustainability, it appears valuable to inquire into this field from the perspective of ESE. The core research interest of this cumulative dissertation is therefore the question of how the connection between time, our needs and sustainability can be conveyed through pedagogical approaches. The inquiry used an exploratory, qualitative research design to address this question. In a first step, the concept of sustainability-related time use competence was developed. This then served as a guiding concept for the understanding of time used in this work and as the overall objective for the educational intervention developed and piloted as part of the research. Next, a content analysis of German curricula was conducted with the aim of determining whether and to what extent these address the relation between time and sustainability. The results show curricula contain only a few starting points that encourage a connection between time and sustainability in school lessons. The study further indicates that an understanding of time as a scarce resource to be used efficiently has prevailed in school contexts so far. The next step involved developing and piloting a time use competence curriculum in cooperation with three partner schools, using an Action Research Approach. This intervention followed the pedagogical approach of Self-Inquiry Based Learning (SIBL) seeking to sensitise learners to the relation between individual needs and consumer behaviour. During implementation, which lasted one semester, students logged their time, were encouraged to reflect on their personal needs, and subsequently implement individual change projects related to time use. This was embedded in continuous reflective individual and group exercises. The results strengthen the hypothesis that there is a relation between time use and sustainability. Furthermore, the pedagogical approach of SIBL has proven suitable to enable students to reflect on their time use and to raise their awareness of the role of individual needs. Participants reported that changes in time use did indeed increase their personal well-being. A third empirical study was carried out, inquiring into students' time use during the period of COVID-19-induced school closures, using a Grounded Theory Approach. Since the pandemic disrupted young peoples' routines drastically, the research focused on which kinds of learning experiences students made during this time and which insights can be derived for ESE. The results of the semi-structured interviews with 69 participants show first that a variety of learning experiences are revealed, such as learning one's own learning and everyday rhythms or creatively adapting consumption habits to the new situation of "lockdown". Overall, a key finding of this work is that students are currently unable to adequately realise their time-related needs. In view of the findings from research on time and sustainability, one recommendation is therefore that everyday school life could give students more space to organise their time according to their needs. Furthermore, it would be advisable to give the topic of time in connection with sustainability more space in curricula and in teacher training. The experiences during the pandemic have shown that schools and all actors involved including students and teachers, are so far insufficiently prepared to handle crises. Here, the approach to time use competence piloted in this work can offer valuable stimulations for ESE research and practice. This is especially true since it is compatible with existing approaches to key competencies for sustainability by seeking to complement them with a stronger focus on individual, needs-oriented time shaping.
To respond to the challenges of the Anthropocene, scholars from various disciplines increasingly emphasize that a mere outer transformation is insufficient and that we also need an inner transformation that addresses deep leverage points. Yet, the open questions are how the inner and outer dimensions relate to each other and how inner transformation might lead to outer transformation. How we attempt to answer these questions is determined by our dominant paradigm. Paradigms define how we understand and shape the world, and thus, they define how we conceptualize challenges, such as inner and outer transformation. Various authors argue that the dominant paradigm, which is characterized by reductionism, empiricism, dualism, and determinism, might be a root cause for insufficiently addressing sustainability challenges. As an alternative, many argue for a relational paradigm, which understands complex phenomena in terms of constitutive processes and relations. A relational paradigm might offer possibilities to reconceptualize inner and outer transformation in the Anthropocene and might shed new light on how to integrate both in sustainability science. Yet, it is still being determined how a relational paradigm can contribute to the understanding of inner and outer transformations towards sustainability in the Anthropocene. Therefore, this dissertation's overarching scope is to contribute to systems change towards a more social-ecological future by generating insights into and exploring possibilities of a relational paradigm for inner and outer transformation in the Anthropocene. This thesis is divided into three sub-questions. The first research question aims to increase the theoretical understanding of a relational paradigm. The second research question aims to develop a transformative educational case study grounded in a relational, justice-oriented approach. The third research question aims to analyze how a relational paradigm might contribute to policies and practices for sustainable lifestyles. The results indicate that inner and outer transformation in the Anthropocene can be reconceptualized as paradigm-ing relationality in the Ecocene. "Paradigm-ing" as an active verb, reconceptualizes inner and outer transformation into ontologies, epistemologies, ethics, and socialecological realities that are ongoing, nonhierarchical, nonlinear, dynamic, co-creative processes of intra-action. The Ecocene decenters the human and attends to what we might be able to intra-actand become-with. These insights can offer unexplored perspectives to address sustainability challenges and increase our capacities to respond in novel ways.
Protected areas are an essential tool for conserving biodiversity. However, their ecological effectiveness is contested and their capacity to resist human pressures differ. This dissertation aimed to assess the ecological effectiveness of different protection levels (from strict to less strictly protected: national park, game reserve, forest reserve, game-controlled area, and unprotected areas) in biodiversity (both mega diverse butterflies and mammals), maintaining habitat connectivity, and reducing anthropogenic threats at the wider landscape in the Katavi-Rukwa Ecosystem of southwestern Tanzania. To achieve this overarching goal, the researcher employed an interdisciplinary approach. First, he analyzed butterfly diversity and community composition patterns across protection levels in the Katavi-Rukwa Ecosystem. He found that species richness and abundance were highest in the game reserves and game-controlled areas, intermediate in the forest reserves, national park and unprotected areas. Species composition differed significantly among protection levels. Landscape heterogeneity, forest cover, and primary productivity influenced species composition. Land-use, burned areas, forest cover, and primary productivity explained the richness of species and functional traits. Game reserves hosted most indicator species. Second, the author modelled the spatial distribution of six large mammal target species (buffalo Syncerus caffer, elephant Loxodonta africana, giraffe Giraffa camelopardalis, hartebeest Alcelaphus buselaphus, topi Damaliscus korrigum, and zebra Equus burchellii) across environmental and protection gradients in the Katavi-Rukwa Ecosystem. Based on species-specific density surface models, he found relatively consistent effects of protection level and land-use variables on the spatial distribution of the target mammal species: relative densities were highest in the national park and game reserves, intermediate in forest reserves and game-controlled areas and lowest in un-protected areas. Beyond species-specific environmental predictors for relative densities, the results highlight consistent negative associations between relative densities of the target species and distance to cropland and avoidance of areas in proximity to houses. Third, the author examined temporal changes in land-use, population densities and distribution of six large mammal target species across protection levels between 1991 and 2018. During the surveyed period, cropland increased. Wildlife densities of most, but not all target species declined across the entire landscape. Based on logistic regression models, target species preferred the national park over less strictly protection levels and areas distant to cropland. Fourth, he quantified land-use changes, modelled habitat suitability and connectivity of elephant over time across a large protected area network in southwestern Tanzania. Based on analyses of remotely-sensed data, cropland increased from 7% in 2000 to 13% in 2019. Based on ensemble models, distance from cropland influenced survey-specific habitat suitability for elephant the most. Despite cropland expansion, the locations of the modelled elephant corridors (n=10) remained similar throughout the survey period. Based on circuit theory, the author prioritizes three corridors for protected area connectivity. Key indicators of corridor quality varied over time, whereas elephant movement through some corridors appears to have increased over time. Overall, this dissertation underpins differences in ecological effectiveness of protected areas within one ecosystem. It highlights the need to utilize a landscape conservation approach to guide effective conservation across the entire protection gradient. It also suggests the need to enforcing land use plans and having alternative and sustainable forms for generating income from the land without impairing wildlife habitat.
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.
Im Kontext der Problematik von Fehlinformationen in der populärwissenschaftlichen Literatur widmet sich diese Arbeit in einer Fallstudie drei häufig verkauften Büchern Peter Wohllebens. Untersucht wird, wie nah diese Werke sich am aktuellen Stand der Forschung orientieren und wie gut die getätigten Aussagen nachvollziehbar sind. Für die Untersuchung wurde der Inhalt der Bücher codiert und die resultierenden 8899 Codiereinheiten quantitativ und qualitativ-vergleichend analysiert. Ergänzt wurde dies durch die qualitativ-vergleichende Analyse von drei Schwerpunktthemen. Aus den Ergebnissen wird geschlussfolgert, dass Wohllebens Nähe zum wissenschaftlichen Diskurs unter Einschränkungen ausreichend und die Nachvollziehbarkeit seiner Aussagen mangelhaft ist. Basierend auf diesen Erkenntnissen werden mögliche Maßnahmen und Handlungsfelder für eine Erhöhung der wissenschaftlichen Qualität populärwissenschaftlicher Werke diskutiert. Es werden weitere potentielle Forschungsmöglichkeiten für ein besseres Verständnis der Situation in den Populärwissenschaften identifiziert und vorgeschlagen.
Neben den Folgen der industriellen Landwirtschaft lassen sich weltweit degradierte Böden, massives Artensterben und ein zunehmender anthropogener Klimawandel verzeichnen. Um diesen Trend zu brechen, muss Landwirtschaft neu gedacht und transformiert werden. Dafür bedarf es innovativer und vor allem nachhaltiger Landnutzungskonzepte. Einen Beitrag zu einem solchen zukunftsfähigen Landnutzungskonzept können Waldgärten leisten. Dabei handelt es sich um mehrschichtige Systeme, welche multifunktional die natürliche Struktur von Wäldern und Waldrändern imitieren. Auf diese Weise können verschiedene Funktionen erfüllt werden, wie beispielsweise die Produktion von vielfältigen Lebensmitteln. Bisher ist das Konzept des Waldgartens in Deutschland noch nicht weit verbreitet. Es wurde bisher wenig wissenschaftliche Forschung auf dem Gebiet betrieben, und in Deutschland existieren bisher nur wenige Waldgärten. In anderen Ländern bestehen hingegen schon länger erste Erfahrungen oder auch schon lange Traditionen mit Waldgärten. Im Folgenden wird die Fallstudie Hof an den Teichen vorgestellt, zusammengefasst, welche Vorarbeiten bereits stattgefunden haben, und das Forschungsziel und die Forschungsfragen hergeleitet.
Crowdfunding is considered a promising instrument for transforming existing socio-technical regimes by financing radical innovations of such entrepreneurs. However, this potential has not yet been fully explored. Therefore, this dissertation addresses the overarching research question of how sustainable entrepreneurs can exploit the full potential of investment-based crowdfunding to develop from niche operators to actors in the socio-technical regime. Five journal articles and one book chapter are included in this PhD project, which use a wide range of quantitative methodologies. In the framework paper, the findings are conceptually evaluated on a meta-level by applying the multi-level perspective. The key insights can be assigned to four categories, including the financing and marketing function, the target group, and the project presentation. The analysis shows that investment-based crowdfunding is suitable to equally fund and market the business ideas of environmental entrepreneurs, since the quest for entering the mass market is highest for such ventures. In contrast, purely social entrepreneurs tend to conduct crowdfunding projects on a smaller scale and probably aim to stay in the niche. Nevertheless, profit-oriented social entrepreneurs are still encouraged to use investment-based crowdfunding for funding and marketing purposes. The prominent display of environmental effects (e.g. the amount of compensated greenhouse gases) and financial incentives (e.g. high interest rates) has a high impact on the investment decision of individuals on investment-based crowdfunding platforms. The case of fairafric is used as a best practice example to demonstrate how crowdfunding can be a stepping stone for sustainability-oriented niche actors to enter the mass market. The fair-trade and organic chocolate manufacturer has undergone six crowdfunding campaigns which enabled it to grow and build a strong community of supporters. The outcomes of this dissertation clarify how sustainable entrepreneurs can unleash the potential of investment-based crowdfunding for financing and marketing purposes.
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.
Human activities have become a major driver of global change, so that global society and economy are facing consequences such as climate change, increasing scarcity of resources, environmental pollution and degradation as well as disturbances of ecosystem functioning and services.In order to meet these main challenges in an appropriate way, adequate starting points and solutions must be pursued at all levels to shift the current socio-economic pathway from an unsustainable to a safe operating and thus sustainable development within the planetary boundaries. One of the application concepts in industrial contexts is Industrial Symbiosis (IS), which deals with the set-up of advanced circular/cascading systems, in which the energy and material flows are prolonged for multiple material and energetic (re-)utilization within industrial systems in order to increase resource productivity and efficiency, while reducing environmental impacts. The overarching goal of the research project was to identify and develop approaches to enable the evolution of Industrial Symbiosis (IS) in Industrial Parks (IPs). IS is a collaborative cross-sectoral approach to connect the resource supply and demand of various industries in order to optimize the resource use through exchange of materials, energy, water and human resources across different companies, while generating ecological, technical, social and economic benefits. Many Information Communication Technology (ICT) tools have been developed to facilitate IS, but they predominantly focus on the as-is analysis of the IS system, and do not consider the development of a common desired target vision or corresponding possible future scenarios as well as conceivable transformation paths from the actual to the defined (sustainability) target state. This gap shall be addressed in this work, presenting the software requirements engineering results for a holistic IT-supported IS tool covering system analysis, transformation simulation and goal-setting. This study also aims to present the conceptual IT-supported IS tool and its corresponding prototype, developed for the identification of IS opportunities in IPs. This IS tool serves as an IS facilitating platform, providing transparency among market players and proposing potential cooperation partners according to selectable criteria (e.g. geographical radius, material properties, material quality, purchase quantity, delivery period). Therefore a quantitative indicator system was compiled and recurring patterns were identified to utilize this knowledge in the comprehensive IT-supported IS tool. So this IS tool builds the technology-enabled environment for the processes of first screening of IS possibilities and initiation for further complex business-driven negotiations and agreements for long-term IS business relationships.
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.
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.
The worldwide decline of plant and insect species during the last decades has far-reaching consequences for the functionality of ecosystems and their inherent processes. Pollination as one of them is an indispensable ecosystem service for human wellbeing. However, an increasing number of pollinator and plant species are threatened by multiple, interacting, and sometimes synergistic causes that are becoming a growing threat to ecosystem functioning. Given the loss of plant species diversity, it is increasingly difficult for pollinators to find food throughout the year. Therefore, this study analyses the influence of plant diversity on pollinators. The study was conducted in the course of the Jena Experiment, which is a long-term biodiversity experiment (since 2002) with 60 plant species, common to Central European Arrhenatherum grasslands. With a plant diversity gradient of 1, 2, 4, 8, 16, and 60 plant species per plot, time-series data resulted from a wide range of ecosystem processes, ranging from productivity, decomposition, C-storage, and N-storage to herbivory, and pollination. These were studied to investigate the mechanisms underlying the relationships between biodiversity and ecosystem processes. Chapter 2 studies the spatio-temporal distribution of pollinators on flowers along an experimental plant diversity gradient. In particular, the spatial pollinator behaviour was examined. Chapters 3 and 4 continues on the chemical composition of flower nectar (nectar) of various plant species. The chemical composition of the nectar was analysed for the two most important macronutrients, carbohydrates (C) and amino acids (AA), using high performance liquid chromatography (HPLC). Subsequently, their contents were analysed in terms of concentration, proportional content and the ratio of carbohydrates to amino acids (C:AA). In Chapter 3, the nectar of 34 plant species from the grasslands of the Jena Experiment was compared. In Chapter 4, nectar was investigated in the context of diversity effects on the example of the plant species Field Scabious, Knautia arvensis. It was analysed to what extent the nectar quality (nutrient content) differs between plant individuals of one species. Overall, these studies indicate how fragile plant-pollinator interactions are but also how important plant species-rich grasslands are to support plant-pollinator interactions. Increased plant species diversity is essential to ensure the availability of flowering resources throughout the year. Pollinators, such as honeybees, bumblebees, solitary bees, and hoverflies can use the niches in time and in vertical space complementarily. However, in plant species-poor grasslands there may be more niche overlaps, which is probably due to a reduced availability of resources. This points to the need to include different plant species belonging to different plant families, whose nectar may have evolved in response to morphological flower traits and metabolic pathways. Therefore plant species diversity can supply pollinators with nectar differing in carbohydrate and amino acid content and thus differing in quality. Also C-AA ratios have proven to be a useful measurement to reveal differences between plant species. In addition, C:AA ratios were not differing in nectar of K. arvensis individuals growing in different plant species richness levels, although their nectar seemed to be more attractive in mixtures with 16 plant species, likely due to higher content of essential and phagostimulatory amino acids than in plant species-poor mixtures.