Open Access

Contemporary society is shaped by the idea that time is, above all, a scarce economic resource that must be used efficiently – “time is money” not to be wasted. 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. So far, this research has often focused on mobility, energy consumption, or the structural conditions of the social organisation of time. Considerably less 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, including in Germany. Given the relation between time, needs and sustainability, it appears valuable to inquire into this field from the perspective of ESE – where time as a resource for sustainability has received comparatively little attention so far. 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. Accordingly, pedagogical approaches to time often focus heavily on time management. 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. This, according to existing evidence from sustainability science, has been found to potentially lead to more sustainable behaviour. At the same time, previous research found that behavioural changes that lead to an increase in well-being do not automatically lead to more sustainable consumption behaviour. Rather, personal attitudes and motivation regarding sustainability are important. This suggests that future ESE interventions aiming at changes in time use should always also contain sufficient opportunities for reflection of values and motives. A third empirical study was carried out, inquiring into students’ time use during the eriod 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 the narrative of students’ learning loss, which is predominant in the current educational science, policy, and media discussion, falls short. Instead, 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. This might be done through pedagogical measures in the classroom, but would also require a stronger institutional anchoring, for example, within the framework of the Whole Institution Approach to Sustainability (WIA), to bring about lasting changes. Furthermore, it would be advisable to give the topic of time in connection with sustainability more space in curricula and in teacher training. This gives rise to future research needs, such as the need to explore how time use competence can be included into everyday pedagogical practice, for instance, by adapting the SIBL approach piloted in a school setting here. It would also call for longitudinal research designs, and it would be of interest to research how time use competence might be incorporated into school development processes. Given the ongoing debate about the impact of the COVID-19 pandemic on schools and education in general, the findings of the research can stimulate both further research and future ESE practice. 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.

The industrial food system is by far the largest greenhouse gas emitting sector. It causes significant damage to terrestrial, aerial and aquatic ecosystems, negative health impacts and an unfair distribution of economic benefits. The call for sustainability transformations is growing, entailing and promoting radical shifts in industrial food systems that lead to new patterns of interactions and balanced social, economic and ecological outcomes. While traditional research has focused on sustainability problems in the food system, it lacks evidence on solutions and desired future states; and more so, on how to practically move from the current to the desired state. Food forests present a promising solution to address multiple sustainability challenges adaptable to local contexts. As biodiverse multi-strata agroforestry systems, they can provide several ecological, socio-cultural and economic services. They sequester carbon, limit soil erosion and regulate the micro-climate; they offer the opportunity for education on healthy diets and ecology, and they produce food and can create livelihood opportunities. However, despite their obvious benefits and a trend in uptake, food forests are still a niche concept rarely known in mainstream culture. To date, research has focused on their ecological and social services; we lack an understanding of food forests as a comprehensive sustainability solution, including their economic dimension, and knowledge on how to develop them. Addressing these gaps, this qualitative research used a solution- and process-oriented methodology guided by transformational sustainability research. In a comparative case study approach, it created an inventory of 209 food forests, followed by interviews and site visits of 14 sites to understand their characteristics and assess their sustainability (Article 1). More indepth, it analyzed the implementation path of seven food forest for success factors, barriers and coping strategies (Article 2). Based on these insights, two experimental case studies were initiated to develop sustainable food forests with practice partners, one based in Phoenix, Arizona, U.S. and one in Lüneburg, Germany. Two studies analyzed the cases’outputs and processes highlighting success factors and challenges, including the role of a sustainable entrepreneurial ecosystem (Article 3, Phoenix case) and key features of productive partnerships to understand why one case succeeded and the other failed (Article 4). Findings include key features of existing and sustainable food forests as well as success factors on how to develop them; namely acquiring a complementary skill set that includes specialty farming and entrepreneurial know-how, securing sufficient start-up funds and long-term land access as well as overcoming regulatory restrictions. Supporting institutions are especially needed to integrate and professionalize the planning stage and provide know-how on alternative business practices. Key features of productive partnerships include an entrepreneurial attitude, access to support functions, long-term orientation and commitment to food system sustainability. The synthesis provides a detailed, ideal-typical implementation pathway to develop sustainable food forests and relevant supportive actors. This study provides researchers, food entrepreneurs, public officials, and activists with insights on how to develop and advance food forests as a sustainability solution.

The global food system faces many complex challenges, and there is general agreement that a transformation is needed. While localizing food has been proposed as a means to this end, changing global food supply chains may also lead to sustainable food systems. Because most food systems today have an international dimension and are likely to remain connected, on one way or another, to other ones across the globe, it is necessary to find solutions to problems such as exploitation or environmental degradation. Current approaches such as Fairtrade certification often result, however, only in incremental change, and it is not clear how the current system could be transformed to make it sustainable. Addressing this challenge and the related gap in the literature, this study examines the emerging practices of small intermediary food businesses, which act between agricultural producers and consumers, and may have the potential to advance sustainability in international food supply. Including a systematic review of the literature on food systems change (Study#1), this dissertation adopts a transformational sustainability research methodology, which is solutionoriented, aims to integrate system, target and transformation knowledge, and is characterized by a transdisciplinary research practice. It conceptualizes challenges of international food supply and empirically investigates entrepreneurial solution approaches to address these challenges (Study#2). Two transdisciplinary research projects with small coffee businesses located in Germany, Mexico, and the U.S. were conducted to examine how these approaches could be implemented (Study#3, Study#4, Workshop reports 1+2). This study shows that challenges in international food supply chains can be conceptualized as negative effects of large geographical and relational distances. It also identifies five entrepreneurial solution approaches specified by twelve sustainability-oriented design principles to address these negative effects. Creating relational proximity between supply chain actors, that is, strong relationships based on knowledge and care, seems to be a key factor to advance sustainability in international food supply.The results also suggest that by building such strong relationships and changing the fundamental principles of international food trade (e.g. putting people before profits), small intermediary businesses could be important agents in food system transformations. The findings also highlight the importance of collaboration with peers in local networks, in which new sustainable business practices could be shared and disseminated. Transdisciplinary collaborations involving both researchers and small food businesses could result in innovative solutions and, ultimately, a transformation of food systems. Although the small-sized businesses examined here are already highly committed to sustainability, this study has important implications for researchers and practitioners, including individual entrepreneurs, who aim to advance sustainability in international food supply.

‚Reallabore‘ erleben als junges Format transformativer Nachhaltigkeitsforschung gegenwärtig eine beeindruckende Konjunktur – ohne das bislang hinreichend geklärt ist, was sie konzeptionell Neues bieten. Die Dissertation arbeitet den Reallabor‐Ansatz aus Perspektive der transdisziplinären Forschung methodisch aus. Die Basis hierfür bildet die Erfahrung mit dem Auf‐ und Ausbau von einem der ersten Reallabore in Deutschland: Das langfristig ausgelegte „Quartier Zukunft – Labor Stadt“ in Karlsruhe transformiert in Kooperation mit der Zivilgesellschaft ein Quartier modellhaft in einen nachhaltigeren Lebensraum. Es setzt dabei gleichermaßen auf Bildung, Forschung und Praxis. Die vorgelegten Texte der kumulativen Dissertation bilden verschiedene Stadien der Entwicklung der Reallaborforschung und der methodologischen Reflexion ab. Die ersten beiden Texte entwickeln eine praxisnahe Definition und ordnen Reallabore ein in verwandte Diskurse. Die folgenden beiden Texte stammen aus der beginnenden Stabilisierung des Reallabordiskurses. Der eine stellt Ziele und Designprinzipien für Reallabore als Rahmen transformativer und transdisziplinärer Forschung dar, der zweite greift aktuelle Diskussionen um Lernprozesse konzeptionell auf. Die letzten beiden Texte fokussieren auf die Ebene der Projekte im Reallabor am Beispiel der Transformativen Projektseminare, einmal in analytischer Perspektive, einmal in methodisch‐didaktischer. Der Rahmentext abstrahiert die Ergebnisse der zuvor publizierten Texte entlang dreier Forschungsfragen und integriert sie zu einem Konzeptmodell transdisziplinärer Forschung im Reallabor, dem „Apfelmodell“. Auf Basis von Diskursen zu Transdisziplinarität, Nachhaltigkeitswissenschaften, Bildungstheorie und Didaktik sowie zu Laboren mit sozialwissenschaftlicher oder interdisziplinärer Ausrichtung werden drei Forschungsfragen verfolgt: Was ist neu am Reallabor‐Ansatz? Welches Potenzial hat ein Reallabor für transdisziplinäre Forschung? Und welche Rolle spielt Lernen im Reallabor? Die methodologische Reflexion führt zu einem Verständnis von Reallaboren als Format zwischen Urban Living Labs und Transition Labs, das sich gegenüber diesen insbesondere durch Langfristigkeit, Bildungsziele und eine klare Trennung zwischen Labor und Experimenten auszeichnet. Aus der kritischen Auseinandersetzung mit Reallaboren wird eine doppelte Bezugnahme auf Transdisziplinarität herausgearbeitet, einerseits als Infrastruktur für transdisziplinäre Projekte, andererseits als in sich transdisziplinäres Unterfangen. Ausgehend von dieser Unterscheidung wird ein Vorschlag gemacht, an welche experimentellen Methodologien jenseits der klassisch‐naturwissenschaftlichen die transdisziplinäre Forschung, die bislang kaum experimentell arbeitet, anknüpfen kann. Das Reallabor unterstützt solche Experimente durch einen Rahmen aus materieller Infrastruktur, durch Kompetenzen der Beteiligten, durch Wissensbestände und soziale Vernetzung. Die Vernetzung über Projektgrenzen hinweg, ein weiteres wesentliches Charakteristikum eines Reallabors, dient dazu, parallele Experimente zu vernetzen und iterative Lernzyklen zu unterstützen. Diese Aspekte werden verbunden zum „Apfelmodell“ transdisziplinärer Forschung im Reallabor, in dem das Reallabor als doppeltes Bindeglied fungiert, einerseits zwischen internen und externen Lernzyklen, und andererseits zwischen wissenschaftlichen, bildungsorientierten und praktischen. Durch die Interpretation der Abläufe im Reallabor als Lernprozesse wird ein Anschluss an Bildungsprozesse auf unterschiedlichen Skalen möglich. Neben Lernprozessen im Reallabor als Lernumgebung lässt sich das Reallabor als lernende Institution und als Kristallisationspunkt gesellschaftlicher Lernprozesse verstehen. Das Apfelmodell kann gleichermaßen im Kontext theoretischer Fragen im Transdisziplinaritätsdiskurs herangezogen werden als auch praktischen Zwecken dienen, insbesondere in der Planung von Reallaboren, in der quervernetzten Konzeption von Projekten darin, in der Evaluation und in der Kommunikation.

Supporting sustainability transformation through research requires, in equal parts, knowledge about complex problems and knowledge that supports individual and collective action to change the system. Recasting the conditions, characteristics, and modes of research processes that address these needs leads to solution-oriented research in sustainability science. This is supported by systematically analyzing the system’s dynamics, envisioning the desired future target state, and by engaging and designing strategic pathways. In addition, learning and capacity building are important crosscutting processes for co-producing required knowledge. In research, we use sophisticated representations as mediators between theories and objects of interest, depicted as visualizations, models, and simulations. They simplify, idealize, and store large and dense amounts of information. Representations are already employed in the service of sustainability, e.g., in communication about climate change. Understanding them as tools to facilitate processes, dialogue, mutual learning, shared understanding, and communication can yield contributions to knowledge processes of analyzing, envisioning, and engaging, and has implications on the design of the sustainability solution. Therefore I ask, what role do representations and representational practices play in the generation of sustainability solutions in different knowledge processes? Four empirical case studies applying rough set analysis, multivariate statistics, systematic literature review, and expert interviews target this research question. The overall aim of this dissertation is to contribute to a stronger foundation and the role of representation in sustainability science. This includes: (i) to explore and conceptualize representations for the three knowledge processes along selected characteristics and mechanisms; (ii) to understand representational practices as tools and embedded into larger methodological frameworks; (iii) to understand the connection between representation and (mutual) learning in sustainability science. Results point toward crosscutting mechanisms of representations for knowledge processes and the need to build representational literacy to responsible design and participate in representational practices for sustainability.