Open Access

In response to the globally increasing environmental, social, and economic crises, we as humanity must leave the path of business as usual and learn new ways to know, think, and act which may enable us to build a more sustainable future for all. In their role as facilitators, teachers in general are considered one, if not the most important, factor for successful learning. The implementation of education for sustainable development (ESD) across all education systems and preparing students to act as future change agents and lead the societal transformation towards sustainability also largely depends on competent and committed teachers. Correspondingly, the focus of political agendas and scientific research increasingly shifts to the effective education of educators. The different competence models that are currently being discussed in the international discourse around teacher education for sustainable development (TESD) suggest various sets of intended learning outcomes (ILOs). Yet, they usually share the assumption that teachers require ESD-related knowledge, pedagogical skills, and motivation to successfully implement ESD at the school level. In accordance with the concept of ESD-specific professional action competence (Bertschy et al., 2013), educational offers in ESD for pre-service teachers should also develop their content knowledge (CK), pedagogical content knowledge (PCK) as well as a positive attitude towards ESD. However, in the sense of a comprehensive construct, this concept has not yet been operationalized or measured. Furthermore, there is still a lack of deeper understanding as to how to best design individual courses as teaching and learning environments in TESD in order to support competence development in student teachers. Based on a dual case study, this cumulative dissertation investigates how individual ESD courses, as part of the teacher education programs at Leuphana University in Lüneburg/ Germany and Arizona State University (ASU) in Tempe/USA, actually foster students’ ESD-specific professional action competence. Furthermore, this work sheds light on the link between learning processes and outcomes, to reveal which factors actually affect the achievement of ILOs and competence development. The findings of this study indicate that both courses under investigation eventually live up to their role and increased student teachers’ competence and commitment to implement ESD in their future careers; yet, mainly due to their different thematic foci, to varying degrees. Additionally, the four Cs (personal, professional, social, and structural connections) were revealed as significant factors that support students’ learning and should be considered when planning and designing course offerings in TESD, with the goal of developing students’ knowledge, skills, and attitudes.

"...as a matter of fact, all that is computerized gained such an amount of reality that nothing could be more mistaken than to call the products of the information technology industry 'virtual'."

Agro-biodiversity can provide natural insurance to risk averse farmers. We employ a conceptual ecological-economic model to analyze the choice of agrobiodiversity by risk averse farmers who have access to financial insurance. We study the implications for individually and socially optimal agro-ecosystem management and policy design when on-farm agro-biodiversity, through ecosystem processes at higher hierarchical levels, generates a positive externality on other farmers. We show that for the individual farmer natural insurance from agro-biodiversty and financial insurance are substitutes. While an improved access to financial insurance leads to lower agro-biodiversity, the e_ects on the market failure problem (due to the external benefits of on-farm agro-biodiversity) and on welfare are determined by properties of the agro-ecosystem and agro-biodiversity’s external benefits. We derive a specific condition on agro-ecosystem functioning under which, if financial insurance becomes more accessible, welfare in the absence of regulation increases or decreases.

The European Union’s Council Regulation on support for rural development by the European Agricultural Fund for Rural Development has introduced auctioning as a new instrument for granting agri-environmental payments and awarding conservation contracts for the recent multi-annual budgetary plan. This paper therefore deals with the conception and results of two case study auctions for conservation contracts. Results of two field experiments show much differentiated bid prices in the model-region and budgetary cost-effectiveness gains of up to 21% in the first auction and up to 36% in the repeated auction. Besides these promising results, some critical aspects as well as lessons to be learned will also be discussed in this paper to improve the design and performance of upcoming conservation auctions.

Online behaviors analysis consists of extracting patterns from server-logs. The works presented here were carried out within the “mBook” project which aimed to develop indicators of the quantity and quality of the learning process of pupils from their usage of an eponymous electronic textbook for History. In this thesis, we investigate several models that adopt different points of view on the data. The studied methods are either well established in the field of pattern mining or transferred from other fields of machine learning and data-mining. We improve the performance of archetypal analysis in large dimensions and apply it to unveil correlations between visibility time of particular objects in the e-textbook and pupils’ motivation. We present next two models based on mixtures of Markov chains. The first extracts users’weekly browsing patterns. The second is designed to process essions at a fine resolution, which is sine qua non to reveal the significance of scrolling behaviors. We also propose a new paradigm for online behaviors analysis that interprets sessions as trajectories within the page-graph. In this respect, we establish a general framework for the study of similarity measures between spatio-temporal trajectories, for which the study of sessions is a particular case. Finally, we construct two centroid-based clustering methods using neural networks and thus lay the foundations for unsupervised behaviors analysis using neural networks. Keywords: online behaviors analysis, educational data mining, Markov models, archetypal analysis, spatio-temporal trajectories, neural network

Online marketing, especially Paid Search Advertising, has become one of the most important paid media channels for companies to sell their products and services online. Despite being under intensive examination by a number of researchers for several years, this topic still offers interesting opportunities to contribute to the com- munity, particularly because of its large economic impact and practical relevance as well as the detailed and widely unfiltered view of consumer behavior that such marketing offers. To provide answers to some of the important questions from advertisers in this con- text, I present four papers in my thesis, in which I extend previous works on optimization topics such as click and conversion prediction. I apply and extend methods from other fields of research to specific problems in Paid Search. After a short introduction, I start with a paper in which we illustrate a new method that helps advertisers to predict conversion probabilities in Paid Search using sparse keyword- level data. We address one of the central problems in Paid search advertising, which is optimizing own investments in this channel by placing bids in keyword auctions. In many cases, evaluations and decisions are made with extremely sparse data, al- though anecdotal evidence suggests that online marketing is a typical

Quality of life and satisfaction with life are of particular importance for individuals as well as for society concerning the “demographic change” with now longer retirement periods. This study will contribute to the life satisfaction discussion and quantifies life satisfaction and pattern of explanation before and after such a prominent life cycle event, the entrance into retirement. In particular, with the individual longitudinal data and 33 waves of the Socio-Economic Panel (SOEP) and the appropriate microeconometric causal fixed effects robust panel methods we ask and quantify if actual life satisfaction indeed is decreasing before re-tirement, is increasing at the entrance into retirement, and is decreasing then after certain periods back to a foregoing level. Thus, we ask if such an anticipation and adaptation pattern– as known from other promi-nent events – is also to discover for life satisfaction before and after retirement in Germany. Main result: Individual and family situation lift life satisfaction after retirement for many years, the (former) occupational situation, however, absorbs this effect both for pensioners and civil service pensioners. It remains only one period of improvement with close anticipation and adaptation at entering retirement but no furthermore significant change compared to pre-retirement life satisfaction. This holds for pensioners (German pension insurance, GRV) but there is no significant effect at all for civil service pensioners.

Organizational culture is widely acknowledged to be a driver of organizational effectiveness. However, existing empirical research tends to focus on investigating the links between individual, isolated culture dimensions and effectiveness outcomes. This approach is at odds with the theoretical roots of organizational culture and does not do justice to the complex reality that most organizations face. This issue is addressed by this dissertation, which is comprised of four studies. Study 1 investigated the psychometric quality and cultural equivalence of three culture measures in a German context, based on a sample of 172 employees in a bank. The results suggested that the German versions of the Denison Organizational Culture Survey and the Organizational Culture Profile performed satisfactorily, while results regarding the GLOBE survey fell short of expectations. The study contributes to facilitating cross-cultural research on organizational culture by providing evidence on instruments that can be applied in international settings, which is an important prerequisite for investigating relationships between culture and effectiveness in an increasingly globalized economy. Study 2 reviewed the literature on the link between culture and effectiveness with a focus on studies that treat organizational culture as a holistic phenomenon. The review yielded four kinds of holistic approaches (aggregation-based, agreement-based, moderation- or mediation-based, and configuration-based). For each approach, main findings, theoretical foundations, and specific avenues for future research are provided. Study 3 investigated how a change in organizational culture induced by an M&A project impacts employee commitment. Based on a sample of 180 employees in a German organization, the findings suggest that individuals perceive cultural change differently, that cultural stability is positively related to employee commitment, and that group-level leader-member exchange and individual self-efficacy moderate this relationship. The study thus contributes to the literature by enabling a better understanding of how cultural change affects employee-related effectiveness factors and by illuminating important contextual factors at the group and the individual level. Study 4 introduced a new theoretical perspective (set theory) and a novel methodology (fuzzy set qualitative comparative analysis) to the field of organizational culture. Across two samples (1170 employees in a financial service provider and 998 employees in fashion retailer), results indicated that culture dimensions do not operate in isolation, but jointly work together in achieving different effectiveness outcomes. The study offers new theoretical and methodological impulses for investigating the culture-effectiveness link. In sum, this dissertation contributes to the literature by providing novel insights that can help researchers to analyze the relationship between organizational culture and effectiveness in a manner that acknowledges both the complexities of organizational reality and of organizational culture´s theoretical roots. Theoretical and practical implications are discussed, and promising directions for future research are identified.

This doctoral thesis deals with the topic of organizational misconduct and covers the three salient research streams in this area by addressing its performance outcomes, antecedents, and preventive measures. Specifically, it is concerned with the question of how different forms of misconduct are reflected in the stock performance of related organizations, thereby, covering the three pillars of corporate sustainability environmental, social, and governance (ESG). Furthermore, it aims to conceptualize how individual cognitive biases may lead to misconduct, therefore, potentially representing an antecedent and how existing management control systems can be enhanced to effectively address specific forms of misconduct, respectively. To these ends, I first review the research stream of stock price reactions to environmental pollution events in terms of the underlying research samples, methodological specifications, and theoretical underpinnings. Based on the findings of the systematic literature review (SLR), I perform three stock-based event studies of the Volkswagen diesel emissions scandal (Dieselgate), workplace sexual harassment (#MeToo accusations), and the 2003 blackout in the US to cove the three ESG dimensions, respectively. In line with the SLR, my event studies reveal substantial stock losses to firms involved in misconduct that are eventually even accompanied by a spillover effect to uninvolved bystanders. Then, I review the extant literature conceptually to develop a framework outlining how moral licensing as an individual cognitive bias might lead to a self-attribution of corporate sustainability, a consecutive accumulation of moral credit, and a later exchange of this credit by engaging in misconduct afterward. Finally, I assess existing workplace sexual harassment management controls, such as awareness training and grievance procedures critically in another conceptual analysis. Based on the shortcomings stemming from management controls’ focus on compliance and negligence of moral duties, I introduce five specific nudges firms should consider to enhance their existing management controls and eventually prevent occurrences of workplace sexual harassment. Based on the six distinct articles within this doctoral thesis, I outline its limitations and point at directions for future research. These mainly address providing further evidence on the long-term performance effects of organizational misconduct, enriching our knowledge on further cognitive biases eventually leading to misconduct, and conceptualizing nudging beyond the use-case of workplace sexual harassment.

Forest ecosystems are complex systems that develop inherent structures and processes relevant for their functioning and the provisioning of ecosystem services that contribute to human wellbeing. So far, forest management focused on timber production while other services were less rewarded. With increasing climate change impacts, especially regulating ecosystem services such as microclimate regulation are ever more relevant to maintain forest functions and services. A key question is how forest management supports or undermines the ecosystems’ capacity to maintain those functions and services. Forest management implies silvicultural interventions such as thinning and timber harvesting and ranges from single tree extraction to large clearcuts as well as forest reserves without active forest operations and shape the character of forest ecosystems (e.g. natural versus planted forests). Artificial plantings, monocultures and management for economic timber production simplify forest structures and impair ecosystem resilience, resistance and the existence of forests but also the services essential for the prosperity and health of humanity. Efforts to reduce the negative impacts and attempts to safeguard forest functions are manifold and include compulsory national and international guidelines and regulations for forest management, conventions, but also voluntary mechanisms such as certification systems. The main objective of this thesis was the development of a concept to assess the functionality of forests and to evaluate the effectiveness of forest ecosystem management including certification. An ecosystem-based and participatory methodology, named ECOSEFFECT, was developed. The method comprises a theoretical and an empirical plausibility analysis. It was applied to the Russian National FSC Standard in the Arkhangelsk Region of the Russian Federation – where boreal forests are exploited to meet Europe's demand for timber. In addition, the influence of forestry interventions on temperature regulation in Scots pine and European beech forests in Germany was assessed during two extreme hot and dry years in 2018 and 2019. Microclimate regulation is a suitable proxy for forest functionality and can be applied easily to evaluate the effectiveness of forest management in safeguarding regulating forest functions relevant under climate change. Microclimate represents the most decisive factor differentiating clearcuts and primary forests. Thus, the assessment of forest microclimate regulation serves as convenient tool to illustrate forest functionality. In the boreal and temperate forests studied in the frame of this thesis, timber harvesting reduced the capacity to self-regulate forests’ microclimate and thus impair a crucial part of ecosystem functionality. Changes in structural forest characteristics influenced by forest management and silviculture significantly affect microclimatic conditions and therefore forest ecosystems’ vulnerability to climate change. Canopy coverage and the number of cut trees were most relevant for cooling maximum summer temperature in pine and beech forests in northern Germany. Maximum temperature measured at ground level increased by 0.21 – 0.34 K when 100 trees were cut. Opening the forest canopy by 10 % caused an increase of maximum temperature at ground-level by 0.53 K (including pine and beech stands). Relative temperature cooling capacity decreased with increasing wood harvest activities and dropped below average values when more than 656 trees per hectare (in 2018; and 867 trees in 2019) were felled. In pine stands with a canopy cover below 82 % the relative temperature buffering capacity was lower than the average. Mean maximum temperature measured at ground-level and in 1.3 m was highest in a pine-dominated sample plots with relatively low stand volume (177 m3 ha-1) and 9 K lower in a sample plot with relatively high stock volumes of F. sylvatica (> 565 m3 ha-1). During the hottest day in 2019, the difference in temperature peaks was more than 13 K for pine-dominated sample plots with relatively dense (72 %) and low (46 %) canopy cover. The Russian FSC standard has the potential to improve forest management and ecological outcomes, but there are shortcomings in the precision of targeting actual problems and ecological commitment. In theory, FSC would transform forest management practices and induce positive changes and effective outcomes by addressing 75 % of the identified contributing factors including highly relevant factors and threats including large-scale (temporary) tree cover loss, which contributes to reducing about half of the identified stresses in the ecosystem. It is theoretically plausible that FSC prevents logging in high conservation value forests and intact forest landscapes, reduces the size and number of clearcuts, and prevents hydrological changes in the landscape. However, the standard was not sufficiently explicit and compulsory to generate a strong and positive influence on the identified problems and their drivers. Moreover, spatial data revealed, that the typical regular clearcut patterns of conventional timber harvesting continue to progress into the FSC-certified boreal forests, also if declared as ‘Intact Forest Landscape’. This results in the need to verify the assumptions and postulates on the ground as it remains unclear and questionable if functions and services of boreal forests are maintained when FSC-certified clearcutting continues. On the clearcuts, maximum temperature exceeded 36 °C and stayed below 30 °C in the closed primary forest. The number of days with temperatures above 25 °C at least doubled on clearcuts. Temperature cooling capacity was reduced by up to 14 % and temperature buffering capacity up to 60 %. The main reason why FSC-certified clearcuts do not differ from conventional clearcuts is that about 97 % of trees within equally large clearcut sites of up to 50 ha were removed. The spatial design of clearcuts, their size and the intensity of clearing as well as the density of skidding trails for timber extraction was not positively influenced by FSC-certification. Annual tree cover loss was lowest in non-certified areas. This means, that FSC may even contribute to an increased biomass removal within the clearcuts, which compromises the ecosystems’ capacity to recover and maintain ecological functions and services. The analysis of satellite-based data on tree cover loss showed that clearcutting causes secondary dieback in the surrounding of the cleared area. FSC-certification does not prevent the various negative impacts of clearcutting and thus fails to safeguard ecosystem functions. The postulated success in reducing identified environmental threats and stresses, e. g. through a smaller size of clearcuts, could not be verified on site. The empirical assessment does not support the hypothesis of effective improvements in the ecosystem. In practice, FSC-certification did not contribute to change clearcutting practices sufficiently to effectively improve the ecological performance. Sustainability standards that are unable to translate principles into effective outcomes fail in meeting the intended objectives of safeguarding ecosystem functioning. Clearcuts that carry sustainability labels are ecologically problematic and ineffective for the intended purpose of ecological sustainability. The overexploitation of provisioning services, i.e. timber extraction, diminishes the ecosystems’ capacity to maintain other services of global significance. It also impairs ecosystem functions relevant to cope with and adapt to other stresses and disturbances that are rapidly increasing under climate change. Forest management under climate change needs to apply precautionary principles and reduce further ecological risks such as secondary dieback and deterioration of regulating services that are relevant for the functioning of forests. Forest managers have to avoid ecological disimprovements by applying strict ecological principles with effective outcomes in order to maintain functional forests that regulate their own microclimate also as a basis for sustainable economic benefits.

The agreement on the 17 Sustainable Development Goals (SDGs) by the UN General Assembly in Septem-ber 2015 was a milestone in the common history of international development and sustainability govern-ance. However, in order to be effective, it is necessary to identify and to define suitable instruments that can be applied in order to fulfill the ambitious goal catalogue. Therefore, the underlying thesis examines the concept of Village Savings and Loan associations (VSLAs) with regard to its mechanisms that operate towards an attainment of the respective goal category. VSLAs are self-government, autonomous and democratically organized Microfinance Institutions (MFIs). They consist of a maximum of 25 mostly fe-male members, who know and trust each other. The work is carried out within a qualitative-empirical research design applied in central Cameroon, which has to some extent exemplary character for sub-Saharan Africa. In this manner, guided experts interviews were conducted with VSLA-presidents as well as with field officers that are creating and accompanying VSLAs. A first part addresses the historical evolu-tion of the SDGs and the theoretical and actual implications of Microfinance and the VSLA-methodology. After considering the methodological proceeding, the results are presented, discussed and summarized in a conclusion. All in all, 22 mechanisms for the attainment of nine SDG-categories are identified and de-scribed. Of particular importance is the key role of the credits to trigger fruitful activities that generate financial wealth, economic growth and employment. Furthermore, the savings of the members are an important factor for the school enrollment of the members´ children. Additionally, a combination of the credits and the solidarity fund improves the medical treatment of the members and their families. In con-trast to that, direct mechanisms supporting the nutritional situation or gender equality in the research field are found to have a limited importance. Moreover, none of the identified mechanisms targets the environmental sphere of the SDG-catalogue. This is weighty in light of an increasing noticeability of the impacts of climate change for the involved population group. Nonetheless, the VSLA-concept is a simple way to effectively address the social and the economic aspects of the SDG-catalogue. In this manner, a further development of the instrument could include the canalization of the capital of international de-velopment co-operation through the VSLAs as democratic and transparent grassroots-institutions.

Traditional farming landscapes typically support exceptional biodiversity. They evolved as tightly coupled social-ecological systems, in which traditional human land-use shaped highly heterogeneous landscapes. However, these landscapes are under severe threats of land-use change which potentially pose direct threats to biodiversity, in particular through land-use intensification and land abandonment. Navigating biodiversity conservation in such changing landscapes requires a thorough understanding of the drivers that maintain the social-ecological system. This dissertation aimed to identify system properties that facilitate biodiversity conservation in traditional farming landscape, focusing specifically on birds and large carnivores in the rapidly changing traditional farmland region of Southern Transylvania, Romania. In order to identify these properties, I first examined the effects of local and landscape scale land-use patterns on birds and large carnivores and how they may be affected by future land-use change (Chapters II-V). Second, to gauge the role of particular traditional land-use elements for biodiversity I focused on the conservation value of traditional wood pastures (Chapters VI-VIII). Third, I took a social-ecological systems approach to understand how links between the social and ecological parts of the system affect human-bear coexistence (Chapters IV and IX). Bird diversity was supported by the broad gradients of woody vegetation cover and compositional heterogeneity. Land-use intensification, and hence the loss of woody vegetation cover and homogenization of land covers, would thus negatively affect biodiversity. This was especially evident from predictions on the distribution of the corncrake (Crex crex) in response to potential future land cover homogenization. Here, a moderate reduction of land cover diversity could drastically reduce the extent of corncrake habitat. Further results showed that the brown bear (Ursus arctos) would mainly be affected by land-use change through the fragmentation of large forest blocks, especially if land-use change would reduce habitat connectivity to the presumed source population in the Carpathian Mountains. Moreover, this dissertation revealed that large carnivores (brown bear and wolf, Canis lupus) may have important and often ignored roles in structuring the ecosystem of traditional farming landscapes by limiting herbivores. Wood pastures were found to have a high conservation value. The combination of low-intensity used grasslands with old scattered trees provided important supplementary habitat for different forest species such as woodpeckers and the brown bear. Worryingly, current management of wood pastures differed from traditional techniques in several aspects, which may threaten their persistence in the landscape. The majority of people had a positive perception on human-bear coexistence. The use of traditional sheep herding techniques combined with the tolerance of some shepherds to occasional livestock predation facilitated coexistence in a region where both carnivores and livestock are present. More generally, the genuine links between people and their environment were important drivers of people´s positive views on coexistence. However, perceived failures of top-down managing institutions could potentially erode these links and reduce people´s tolerance towards bears. Through the consideration of two different animal taxa, this dissertation revealed six important system properties facilitating biodiversity conservation in traditional farming landscapes. Similar proportions of the main land-use types (arable land, grassland, and forests) support species richness at the regional scale possible through habitat connectivity and continuous spill-over between land-use types. Heterogeneous landscapes can further support biodiversity through complementation and supplementation of habitat at the landscape scale. Gradients of woody vegetation cover and heterogeneity, supported biodiversity at both local and landscape scales possibly through the provision of a wide range of resources. The heterogeneous character of the landscape is tightly linked to traditional land-use practices, which also maintain specific traditional land-use elements and facilitate human-carnivore coexistence. Top-down limitation of large carnivores on herbivores possibly enhances vegetation growth and tree regeneration. The genuine links between humans and nature support human-bear coexistence, and these links may form the core of people´s values and sustainable use of natural resources.

Through the expansion of human activities, humanity has evolved to become a driving force of global environmental change and influences a substantial and growing part of natural ecosystem trophic interactions and energy flows. However, by constructing and building its own niche, human distance from nature increased remarkably during the last decades due to processes of globalization and urbanization. This increasing disconnect has both material and immaterial consequences for how humans interact and connect with nature. Indeed, many regions across the world have disconnected themselves from the productivity of their regional environment by: (1) accessing biological products from distant places through international trade, and (2) using non-renewable resources from outside the biosphere to boost the productivity of their natural environment. Both mechanisms allow for greater resource use then would be possible otherwise, but also involve complex sustainability challenges and lead to fundamentally different feedbacks between humans and the environment. This dissertation empirically investigates the sustainability of biophysical human-nature connections and disconnections from a social-ecological systems perspective. The results provide new insights and concrete knowledge about biophysical human-nature disconnections and its sustainability implications, including pervasive issues of injustice. Through international trade and reliance on non-renewables, particularly higher-income regions appropriate an unproportional large share of global resources. Moreover, by enabling seemingly unconstrained consumption of resources and simultaneous conservation of regional ecosystems, increasing regional disconnectedness stimulates the misconception of decoupling. Whereas, in fact, the biophysically most disconnected regions exhibit the highest resource footprints and are, therefore, responsible for the largest environmental damages. The increasing biophysical disconnect between humans and nature effectively works to circumvent limitations and self-constraining feedbacks of natural cycles. The circumvention of environmental constraints is a crucial feature of niche construction. Human niche construction refers to the process of modifying natural environments to make them more useful for society. To ease integration of the chapters in this thesis, the framework paper uses human niche construction theory to understand the mechanisms and drivers behind increasing biophysical disconnections. The theory is employed to explain causal relationships and unsustainable trajectories from a holistic perspective. Moreover, as a process-oriented approach, it allows connecting the empirically assessed states of disconnectedness with insights about interventions and change for sustainability. For a sustainability transformation already entered paths of disconnectedness must be reversed to enable a genuine reconnection of human activities to the biosphere and its natural cycles. This thesis highlights the unsustainability of disconnectedness and opens up debate about how knowledge around sustainable human niche construction can be leveraged for a reconnection of humans to nature.

Despite growing research on sustainability transformations, our understanding of how transformative transdisciplinary research can support local actors who foster change towards sustainability is still somewhat limited. To contribute to this research question, I conducted research in a transdisciplinary case study in Southern Transylvania, where non-governmental organizations (NGO) drive sustainability initiatives to foster desired changes (e.g., supporting small-scale farmers or conserving natural and cultural heritage). Interactions with these local actors and reflections on my research question shaped the research of this dissertation, which I present in four papers. In paper 1, I conducted a literature review on amplification processes that describe actions, which local actors can apply to increase the impact of their sustainability initiatives. This is of interest in sustainability transformations research and practice because the impact of initiatives challenges incumbent regimes and consequently prepares transformations. I developed an integrated typology of amplification processes, which introduces new and innovative ways to conceptualize and study how initiatives increase their impact. The typology integrates theoretical insights on amplification processes from different frameworks that draw on diverse theories, such as resilience theory on transformations of social-ecological systems or sustainability transitions theory on transitions of socio-technical systems. This typology combines contemporary conceptualizations of amplification processes, informs transdisciplinary researchers working with local actors on increasing impact from initiatives, and has inspired debate and empirical research which contributes to theory development concerning amplifying impact of initiatives in diverse contexts. In paper 2, I conducted a literature review on the application of indigenous and local knowledge (ILK) in sustainability transformations research to understand whether this research engages with the conceptualization of transformations from local actors. The results show that ILK is generally applied to confirm and complement scientific knowledge in contexts of environmental, climate, social-ecological, and species change. Only four out of 81 papers (5%) applied ILK to conduct research on transformations. In addition, I identified four research clusters that apply ILK in contexts of transformation, transition, or change in Arctic, terrestrial, coastal, and grass and rangelands environments. Consequently, the review shows that only few empirical studies apply ILK to understand transformations. This indicates that sustainability transformations research lacks to include knowledge from local actors to conceptualize transformations, such as in the case of ILK. This has the potential to question scientific conceptualizations of transformations for theory development (e.g., resilience theory on transformations of social-ecological systems) and to enrich transformative transdisciplinary research. In paper 3, I derived principles that provide guidance for how to integrate sustainability initiatives from local actors in transformative transdisciplinary research. Based on my transdisciplinary research with the NGOs in Southern Transylvania and by using systems and futures thinking as an approach for analysis, I derived three principles that provide guidance for the co-design of sustainability intervention strategies that build on, strengthen, and complement existing initiatives from local actors. These principles contribute to transformative transdisciplinary research by highlighting and operationalizing the need to integrate initiatives from local actors to foster bottom-up, place-based transformations. In paper 4, I explored empirically how to identify relevant local actors for collaborations that seek to intervene in specific characteristics of a system (e.g., parameters or design of a system). I applied a leverage points’ perspective to analyse the social networks of the NGOs in Southern Transylvania that amplify the impact of their initiatives. My results suggest that there are two types of local actors for potential collaborations: local actors who have the ability to intervene in both shallow (i.e., parameters and feedbacks of a system) and deep (i.e., design and intent of a system) system characteristics, and local actors who have the ability to intervene only in specific system characteristics. In addition, my results indicate that the application of specific amplification processes is associated with the positions of local actors in their networks. Thus, paper 4 provides a novel methodological approach and first empirical insights for identifying potential relevant partners for specific system interventions. This supports in transformative transdisciplinary research the categorization of relations and networks of local actors according to the system characteristics that they address, and the selection of relevant partners for specific system interventions. This dissertation as a whole contributes insights to three recommendations of how transformative transdisciplinary research can support local actors fostering change towards sustainability: First, by conducting research that studies and supports local actors who increase the impact of their sustainability initiatives via amplification processes (Paper 1 and 4); Second, by engaging specifically with the initiatives, networks, and knowledge from local actors, who foster bottom-up, place-based transformations (Paper 1-4); Third, by identifying and collaborating with local actors that are relevant for strategic systems interventions that build on, strengthen, and complement existing initiatives (Paper 3-4). These three recommendations pave the way for an enhanced transformative transdisciplinary research that can potentially support local actors who with their initiatives, networks, and knowledge foster bottom-up, place-based sustainability transformations.

This dissertation deals with the relationships between the increasingly discussed business model notion, sustainability innovation, and the business case for sustainability concept. The main purpose of this research is to identify and define the so far insufficiently studied theoretical interrelations between these concepts. To this end, according theoretical foundations are developed and combined with empirical studies on selected aspects of the solar photovoltaic industry. This industry is particularly suitable for research on sustainability innovation and business models because of its increasing maturity paired with public policy and market dynamics that lead to a variety of business model-related managerial and entrepreneurial business case challenges. The overarching research question is: How can business models support the commercialisation of sustainability innovations and thus contribute to business cases for sustainability? A theoretical and conceptual foundation is developed based on a systematic literature review on the role of business models in the context of technological, organisational, and social sustainability innovation. Further, the importance of business model innovation is discussed and linked to sustainability strategies and the business case for sustainability concept. These theoretical foundations are applied in an in-depth case study on BP Solar, the former solar photovoltaic subsidiary of British Petroleum. Moreover, because supportive public policies and the availability of financial capital are known to be the most important preconditions for commercial success with innovations such as solar photovoltaic technologies, the solar studies include a comparative multiple-case study on the public policies of China, Germany, and the USA as well as a conjoint experiment to explore debt capital investors’ preferences for different types of photovoltaic projects and business models. As a result, the main contribution of this work is the business models for sustainability innovation (BMfSI) framework. This framework is based on the idea that the business model is an artificial and social construct that fulfils different functions resulting from social interaction and their deliberate construction. The BMfSI framework emphasises the so-called mediating function, i.e. the iterative alignment of business model elements with company-internal and external requirements as well as with the specific characteristics of environmentally and socially beneficial innovations. Against this backdrop, it becomes clear that practically-oriented knowledge based on BMfSI research might provide new and effective ways to support the achievement of corporate sustainability.

This paper-based dissertation deals with capital structures and tax policies of German family businesses. The provision of sufficient financial resources is crucial for a firm’s survival and thus represents a central task for a firm’s management. Family firms as the predominant company form in Germany are mainly characterized by the overlapping of the two spheres family and business, both having different goal systems and preferences. This also has an impact on decision making with regard to corporate finance including the application of tax avoidance policies. In Germany, bank finance is the dominant financing source for family firms but there is a preference for internal finance since it comes along with more external independency. Extant research usually bases its results on samples of publicly listed companies. These studies come up with different results regarding family firms’ actual financing preferences and capture their heterogeneity only to a very little extent. In this light, the present dissertation and its three papers examine different research questions in the context of capital structure decisions and tax avoidance in family firms. All the three papers apply a quantitative empirical research design. The first paper is a comparison between capital structures of family firms and non-family firms. The paper examines differences in bank debt and trade credit ratios. Overall, the findings show that family firms have significantly higher overall and long-term debt levels compared to their non-family counterparts. The identity as a family firm, which leads to a leap of faith by banks, can be a possible explanation for these results. The second paper is an in-depth examination of drivers of bank debt levels within the group of family firms. Further, it addresses heterogeneity amongst family firms and combines survey results and corresponding financial information. This represents a first attempt to capture family firm heterogeneity and its link to financial issues. The study shows that the more power in the company is exerted via management or supervisory board by the family, the less bank debt is used. Paper three is an extension of the previous two studies as it sheds light on tax avoidance, a significant instrument to strengthen the internal financing capability of a firm. This also takes up a research gap as there is very little research on taxation in family firms. Contrary to the expectation, the study reveals that private family firms might pay less tax than their non-family peers.

The currently widespread agricultural practices have been increasingly criticised in recent years. They are especially criticised for being unsustainable on an ecological, economic and social level (compare Kalfagianni & Skordili, 2019). Recent developments in the global food system lead to a lack of transparency and unethical practices with negative impacts on human health and the environment from the consumer’s perspective (Wellner & Theuvsen, 2017, p. 235) and to pressure of modernisation and intensification processes from the producer’s perspective. This results in fear for farmers’ existences (Boddenberg et al., 2017, p. 126) and leads to an increased vulnerability of the current food system (Kalfagianni & Skordili, 2019, pp. 3–4). It endangers long-term reliable food provisions and therefore calls for a change of supply and production practices.

In this dissertation, a multi-proxy study, which included palaeoecological, lithological, geochemical and geochronological methods, was carried out to investigate climatic and environmental changes and their interaction during the Quaternary in formerly glaciated and non-glaciated areas. The information obtained will be used to provide a better understanding of the regional stratigraphic framework and to establish broader regional terrestrial correlations within the global marine isotope stage (MIS) framework. This study was conducted on two key drillings, the Garding-2 research drill core in the German North Sea coastal area of Schleswig-Holstein and the GBY#2 archaeological core at the Gesher Benot Ya´aqov (GBY) site, in the Upper Jordan Valley in Israel. The results of this study are presented in three papers. Papers I and II focus on the study of the Garding-2 core, while the multi-proxy study of the GBY#2 core is presented in Paper III. The results of a variety of analyses conducted on the 240 m long Garding-2 sequence show interglacial-glacial cycles that are mainly controlled by variations in temperature. This sequence is composed of mainly fluvial-shallow marine sediments intercalated by muddy-peaty deposits. Based on the palynological and lithological findings, the Pliocene-Pleistocene transition was observed at 182.87 m. It is overlain by Praetiglian and the subsequent sediments of the Waalian and Bavelian Complexes. The boundary of either the second or third Cromerian Interglacial with younger sediments, which still belong to MIS 19, is marked by the last occurrence of Tsuga at 119.50 m and the development of mixed-deciduous forests. The palynologically equivalent sediments of the Bilshausen Interglacial were found below two Elsterian till layers, at 89.00 m-82.00 m. These sediments showed high and increased percentages of Pinus and Picea and scattered occurrences of Abies and Carpinus, which are similar to the features of the beginning of the Bilshausen or Rhume interglacial (Müller, 1992). An unconformity occurred at 80.29 m, at the bottom of late Holsteinian deposits, characterised by the occurrences of Fagus and Pterocarya, with low percentages of Abies and Carpinus and the absence of Buxus. These deposits are succeeded by sediments of the Fuhne cold period that shows higher percentages of NAP and occurrences of Ericales, Helianthemum and Selaginella selaginoides, which are unconformably overlain by Drenthian till at 73.00 m-71.00 m. A single peaty sample at 69.25 m with Pinus-Picea-Abies assemblage is correlated with the late Eemian Interglacial. This deposit is overlain by Weichselian glaciofluvial sediments. Middle-late Holocene sediments occurred from 20 m upwards, following a hiatus, which was caused by the Early Holocene transgression. A subsequent thin layer of marine Atlantic sediments is unconformably overlain by marine-tidal flat deposits up to 11.00 m. The first occurrence of Fagus (at 15.97 m) and Carpinus (at 15.03 m), which was optically stimulated luminescence (OSL)-dated to 3130 +/- 260 BP (at 16.22 m, Zhang et al., 2014), gives evidence for a Subboreal age for these deposits. Sandy sediments of the early Subatlantic, which were deposited between 11.00 m and the top of the Garding-2 sequence, indicate that local salt marshes, dunes and tidal flat vegetation expanded during this period. Due to regional features and the peculiarities of the local coastal environment, the expansions of Fagus and Carpinus, which are characteristic for the Subboreal-Subatlantic transition at about 2700 BP in northern Germany, are not clearly reflected in the Garding-2 pollen diagram. In the Mediterranean area, a 50 m long core of GBY#2, was drilled at the Acheulian site of Gesher Benot Ya´akov. The GBY#2 core provides a long Early-Middle Pleistocene geological, environmental and climatological record, which also enriches the knowledge of hominin-habitat relationships documented at the margins of the Hula Palaeo-lake. The sediment sequence of GBY#2 is under- and overlain by two basalt flows that are 40Ar/39Ar dated: two samples at the bottom of the core dated to 1195 +/- 67 ka (at 48.30 m) and 1137 +/- 69 ka (at 45.30 m), and another one at the top dated to 659 +/- 85 ka (at 14.90 m). With the additional chronological identification of the Matuyama Brunhes Boundary (MBB) and the correlation with the GBY excavation sites, the sedimentary sequence of GBY#2 provides the climatic history during the late part of the mid-Pleistocene transition (MPT, 1.2 Ma-0.5 Ma). Multi-proxy analyses including those of pollen and non-pollen palynomorphs, macro botanical remains, molluscs, ostracods, fish, amphibians and micromammals provide evidence for lake and lake-margin environments during MIS 20 and MIS 19. During MIS 20, relatively cool semi-moist conditions were followed by a pronounced dry phase. During the subsequent MIS 19, warm and moist interglacial conditions were characterised by Quercus-Pistacia woodlands in this area. The depositional environment changed from an open water lake during MIS 20 to a lake margin environment in MIS 19. This finding is at odds with changing climate conditions from relatively dry to moist. This discrepancy could be explained by the prograding pattern of the lake shore due to the infilling of the basin, which resulted in shallower water. Climatic changes during the Late Tertiary and the Quaternary in the high latitude regions in northwest Europe and during the Early-Middle Pleistocene in the mid latitude regions of the Middle East follow the patterns of global climatic changes, which are mainly controlled by orbital obliquity (+/-41 ka cycle) during the Early Pleistocene and by orbital eccentricity (+/-100 ka cycle) during the MPT (1.2 Ma-0.5 Ma) and the younger periods of the Quaternary. The results of this study also provide reliable evidence for long distance correlation of stratigraphic and climatic events of the Quaternary, which extends knowledge of regional and global impact of climatic fluctuations on the environment.

This research report presents a transdisciplinary student research project on the development of climate resilience of communities on the Caribbean Island Dominica. The research was conducted through a partnership between the Leuphana University Lüneburg and the Sustainable Marine Financing Programme (SMF) of the GIZ. For the GIZ, the research project aimed at improving the understanding of the socio-ecological resilience framework for tackling problems of Marine Managed Areas and Marine Protected Areas. Also, it enabled new thoughts on how the GIZ and other development agencies can more effectively assists island states to better cope with the challenges of climate change. The role of the students from the “Global Environmental and Sustainability Sciences” programme of Leuphana University included the design of four transdisciplinary research projects to research aspects of resilience of Caribbean communities. The developing island states in the Caribbean are extremely vulnerable to more frequent and intense natural hazards while relying on the ecosystem services that are also at risk from extreme weather events, in particular Hurricanes. Low economic stability leads to a dependency of the states on international assistance. To decrease the vulnerability to shocks, counteracting measures that encourage learning and adaptation can increase the resilience against extreme weather events and their consequences. Concepts that were considered during the design of the transdisciplinary research projects were the adaptation of systems, diversity and stakeholder participation and resilience-focused management systems. Also, the students critically assessed the concept of foreign aid and how it can be successful, mitigating the risk of introducing neo-colonial structures. Flood Management, Biodiversity, Small-Scale Agriculture and Foreign Aid on Dominica were the topics of the transdisciplinary projects. The research methods of a literature review, stakeholder mapping, interviews, scenario development and visioning were used in the projects. In four scenarios developed in the ‘Flood Management’ project, it became evident that a broad as well as coordinated stakeholder engagement and a variety of measures are required for community resilience. A key finding of the ‘Biodiversity’ project was the identity dimension of community resilience, underlining the importance of the relationship between individuals and nature. The interlinkage of social identity processes and a resilient disaster response was also stressed by the project ‘Foreign Aid’, which highlighted that financial support is similarly important to inclusivity and reflexivity in the process of resource distribution. To recover from extreme weather events, the social memory also plays an important role. The project on ‘Small-scale Agriculture’ concluded, that the memory-making of local communities is as vital to community resilience as formal plans and trainings. The research project was based on the research approach of transdisciplinarity because of its solution-orientation. It links different academic disciplines and concepts, and non-scientific stakeholders are included to find solutions for societal and related scientific problems. In the four projects, principles of transdisciplinary research were party applied, but some challenges arose due to the geographical distance, time constraints and a strong focus on the scientific part in some phases. Nonetheless, the findings of the projects provide valuable learning lessons to be applied in practice and that can prove useful for future research.

Smartphones make intensive use of precious metals and so called conflict minerals in order to reach their high performance in a compact size. In recent times, sustainability challenges related to production, use and disposal of smartphones are increasingly a topic of public debate. Thus, established industry actors and newly emerging firms are driven to engage in more sustainable practices, such as sustainable sourcing of materials, maintenance services or take-back schemes for discarded mobile phones. Many of these latter efforts can be related to the concept of a circular economy (CE). This thesis explores how CE-related value creation architectures (VCAs) in the smartphone industry contribute to slowing and closing resource loops in a CE. In order to analyze these new industry arrangements, transaction cost theory (TCT) is used as a guiding theory for a make-or-buy analysis. Combining TCT with the concept of a CE is a novel research approach that enables the empirical analysis of relationships between focal actors (e.g. manufacturers) and newly emerging loop operators (e.g. recycling firms) in the smartphone industry. Case studies of such VCAs are conducted with case companies drawn from the Innovation Network on Sustainable Smartphones (INaS) at Leuphana Universtity of Lüneburg and analyzed regarding their involved actors, partnerships, circular activities, motivation and perceived barriers. Evidence from the conducted case studies suggests that asset specificity for circular practices increases for higher order CE-loops such as maintenance or reuse, therefore long-term partnerships between focal actors and loop operators or vertical integration of CE practices are beneficial strategies to reach a sophisticated CE. Similarly, circular practices that go beyond recycling require a strong motivation, either through integration in the focal firm´s quality commitment or through business model recognition. It is further suggested that the circular design of products and services could reduce necessary transaction costs and thus overall costs of a circular economy. Four different integration strategies for circular economy practices have been derived from the conducted case studies. These are: 1) vertically integrated loops, 2) cooperative loop-networks, 3) outsourcing to loop operators and 4) independent loop operators. This work thus provides evidence that circular economy activities do not necessarily have to be managed by focal actors in the value chain. Rather, circular practices can also be put forward by specialized loop operators or even independent actors such as repair shops.

The postal sector has a long monopolistic tradition in many countries; however, since the 1990s it has undergone considerable changes. At the beginning of that decade, the European Commission abolished exclusive rights within the postal system and opened up the market to new private postal providers and changes have continued to accelerate after two important European directives. Both directives were intended to improve the quality of service in the industry and to open up the market to competition. What has changed since the opening of the German postal market? A look at market shares measured by volumes of processed postal items, or by revenue, quickly reveals the prevailing dominance of the former monopolist Deutsche Post AG (DPAG). Despite an increasing number of market entries by private postal providers, it seems the German postal market is still characterized by the old monopolistic structures and that the aim of creating a competitive environment has not been fully achieved. This thesis deals with different competition issues from an economics perspective. The analyses are based on self-collected data and in-depth interviews conducted during on-site visits and thus provide first empirical evidence regarding the status quo in the German postal market.

Extracting meaningful representations of data is a fundamental problem in machine learning. Those representations can be viewed from two different perspectives. First, there is the representation of data in terms of the number of data points. Representative subsets that compactly summarize the data without superfluous redundancies help to reduce the data size. Those subsets allow for scaling existing learning algorithms up without approximating their solution. Second, there is the representation of every individual data point in terms of its dimensions. Often, not all dimensions carry meaningful information for the learning task, or the information is implicitly embedded in a low-dimensional subspace. A change of representation can also simplify important learning tasks such as density estimation and data generation. This thesis deals with the aforementioned views on data representation and contributes to them. We first focus on computing representative subsets for a matrix factorization technique called archetypal analysis and the setting of optimal experimental design. For these problems, we motivate and investigate the usability of the data boundary as a representative subset. We also present novel methods to efficiently compute the data boundary, even in kernel-induced feature spaces. Based on the coreset principle, we derive another representative subset for archetypal analysis, which provides additional theoretical guarantees on the approximation error. Empirical results confirm that all compact representations of data derived in this thesis perform significantly better than uniform subsets of data. In the second part of the thesis, we are concerned with efficient data representations for density estimation. We analyze spatio-temporal problems, which arise, for example, in sports analytics, and demonstrate how to learn (contextual) probabilistic movement models of objects using trajectory data. Furthermore, we highlight issues of interpolating data in normalizing flows, a technique that changes the representation of data to follow a specific distribution. We show how to solve this issue and obtain more natural transitions on the example of image data.