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Ökologische und soziale Themen werden für Marken zunehmend erfolgsrelevant. Jedoch können Nachhaltigkeitsversprechen einer Marke zu Vertrauensvorbehalten seitens der Stakeholder führen, weshalb die Glaubwürdigkeit einer Nachhaltigkeitsmarke besonders wichtig ist. Zudem wird die Wahrnehmung einer Nachhaltigkeitsmarke heutzutage verstärkt durch Stakeholder mitbestimmt, da sie mittels Social Media eigene Inhalte verfassen und im Social Web veröffentlichen können. Vor diesem Hintergrund wurde in der Dissertation erörtert, wie ein Unternehmen seine Marke durch ökologische und soziale Themen stärken kann. Außerdem wurde untersucht, wo in diesem Entwicklungsprozess soziale Medien gezielt eingesetzt werden können. In diesem Kontext wurde auch der Frage nachgegangen, wie die von Stakeholdern im Social Web verfassten Inhalte in Übereinstimmung mit einer intendierten Nachhaltigkeitsmarke gebracht und deren Kraft genutzt werden können. Zentrales Ergebnis der Dissertation stellt ein anwendungsorientiertes Modell für die systematische Social-Media-Verwendung zur Unterstützung des Nachhaltigkeitsmarkenmanagements dar.
Algae-bacteria-based biotechnology has received more and more attention in recent years, especially in the subtropical and tropical regions, as an alternative method of conventional multistep wastewater treatment processes. Moreover, the algal biomass generated during wastewater treatment is regarded as a sustainable bioresource which could be used for producing biofuel, agricultural fertilizers or animal feeds. Although this technology is attractive, a number of obstacles need to be solved before large-scale applications. The main purposes of this work are to find more effective biomass harvesting strategies and develop high-effective algal-bacterial systems to improve wastewater treatment performance, biomass generation rate and biomass settleability. A wastewater-borne algal-bacterial culture, cultivated and trained through alternate mixing and non-mixing strategy, was used to treat pretreated municipal wastewater. After one month cultivation and training, the acclimatized algal-bacterial system showed high carbon and nutrient removal capacity and good settleability within 20 minutes of sedimentation. Algal biomass uptake was the main removal mechanism of nitrogen and phosphorus. The biomass productivity, nitrogen and phosphorus accumulation in biomass during the wastewater treatment process were investigated. The characterization of the microbial consortium composition in the enriched algal-bacterial system provided new insights in this research field. Aerobic activated sludge which already showed good settleability was used as bacterial inoculum to enhance the wastewater treatment performance and biomass settleability of algal-bacterial culture. The influence of different algae and sludge inoculum ratios on the treatment efficiency and biomass settleability was investigated. There was no significant effect of the inoculation ratios on the chemical oxygen demand (COD) removal. But algae/sludge inoculum ratio of 5 showed the best nitrogen and phosphorus removal efficiencies (91.0 ± 7.0% and 93.5 ± 2.5%, respectively) within 10 days. Furthermore, 16S rDNA gene analysis showed that the bacterial communities were varying with different algae and sludge inoculation ratios and some specific bacteria species were enriched during the operation. Four commonly used and high-potential microalgae species including one cyanobacteria (Phormidium sp.) and three green microalgae species (Chlamydomonas reinhardtii, Chlorella vulgaris and Scenedesmus rubescens) were cultivated and trained through alternate mixing and non-mixing strategy for tertiary municipal wastewater treatment. After one month of cultivation, the four microalgae species were compared in terms of biomass settleability, nutrient removal rates and biomass productivity. The three green microalgae showed good settleability within 1 h sedimentation and had higher biomass generation rates (above 6 g/m2/d). The nutrient removal efficiencies were 99% for the four selected microalgae species but within different retention time, resulting in 3.66 ± 0.17, 6.39 ± 0.20, 4.39 ± 0.06 and 4.31 ± 0.18 mg N/l/d (N removal rate) and 0.56 ± 0.07, 0.89 ± 0.05, 0.76 ± 0.09 and 0.60 ± 0.05 mg P/l/d (P removal rate) for Phormidium sp., Chlamydomonas reinhardtii, Chlorella vulgaris and Scenedesmus rubescens, respectively. A mixed algal culture composed of three selected high-effective green microalgae (Chlamydomonas reinhardtii, Chlorella vulgaris and Scenedesmus rubescens) was used for tertiary municipal wastewater treatment. The key biotic factor (algal inoculum concentration) and abiotic factors such as illumination cycle, mixing velocity and nutrient strength were studied. Based on the nitrogen and phosphorus balance, it was found that assimilation into algal biomass was the main removal mechanism.
Scaling Strategies of Social Entrepreneurship Organizations – an Actor-Motivation Perspective
(2014)
Despite their sometimes ingenious solutions, many social entrepreneurs fail to scale which is at odds with their overall objective of social change. Yet, though considered highly important in practice, scaling is still under-researched. Taking this imbalance as a starting point, my PhD thesis contributes to the social entrepreneurship literature by shedding new light on the role of the actor-motivation in scaling social ventures. Put together, papers 1-3 try to answer the general research questions of how do actors and their specific motivations, particularly the social entrepreneur, influence the scaling strategies (and success) of social ventures? Based on a brief review of the literature on scaling, I identify social franchising as a promising scaling strategy that requires more research. Here, paper 1 argues that the social mission of the involved actors can serve as an informal functional equivalent to formal contracts as well as a means to safeguard the local small group logic. Paper 2 discusses the effects of stewardship on social franchising coming to the conclusion that stewardship relationships may impede speed of and degree of scaling. Based on these insights, paper 3 more closely analyzes the motivations of social entrepreneurs in a post-founding stage. It empirically constructs a taxonomy of (social) entrepreneurs based on their motivations. To this end, paper 3 employs a three-step methodological approach that combines the inductive insights from 80 interviews with entrepreneurs with a statistical cluster analysis. Following, this paper then discusses contributions of and implications for scaling research as well as to social entrepreneurship, entrepreneurship, and management research.
Human activities have converted natural ecosystems worldwide, mostly for agricultural purposes. This change in land use has been recognized as one of the key drivers causing mass extinction of biodiversity. Yet, there are species which persist particularly in traditional, low-intensity agricultural areas. However, this farmland biodiversity is increasingly threatened by the consequences of land-use intensification and land abandonment. One effect of these two processes is the change in existing landscape structures. This dissertation aimed at quantifying the relationship between biodiversity and landscape structures because a better understanding of current biodiversity patterns and their drivers is needed to navigate biodiversity conservation for a sustainable development. Specifically, this dissertation anticipates the impacts of land-use change on biodiversity in Southern Transylvania, focusing on butterflies and plants as study groups. In a first step, a methodological baseline for subsequent biodiversity studies is developed by exploring an optimal survey strategy, allocating the available resources in a study design that enables high statistical power and covers a wide range of environmental conditions. This study shows that in the highly heterogeneous farmland mosaic of Southern Transylvania, survey effort can be moderately reduced while still showing similar patterns of species richness, species turnover and species composition (Chapter 2). In a second step, biodiversity patterns of plants and butterflies are empirically investigated in response to different landscape structures, particularly towards heterogeneity and woody vegetation cover. These studies provide evidence that all main land-use types in Southern Transylvania, namely arable land, grassland and forests, contribute to an overall landscape pool. Species richness of plants, but not of butterflies, differed significantly between arable land and grassland. Presence of woody vegetation in farmland had a positive effect on plant species richness. Heterogeneity has been found beneficial for butterfly species richness in arable land, but not in grasslands. Species composition of plants was determined by land-use, but butterfly species composition was widely overlapping in arable land and grassland (Chapters 3 & 4). Investigations on the potential spread of invasive plant species in the Transylvanian landscape exhibited that distance to roads and heterogeneity, especially in arable land, were key variables determining the invasibility of the landscape (Chapter 5). By studying movement patterns of butterflies in agricultural landscapes, land-use intensity could be revealed having an impact on butterfly movements. Furthermore, butterflies were found to prefer non-arable patches within farmland (Chapter 6). In a third step, this dissertation conceptually embeds socio-economic considerations into the local and international discourse on sustainable rural development: Reflections on a participatory projects on establishing butterfly monitoring in Romania conclude that involving citizens in biodiversity conservation is possible in Romania, but need tailored approaches which consider the unique social and cultural settings (Chapter 7). Current recommendations from scientific literature to increase the agricultural yield, for example in Eastern European landscapes, through ´sustainable intensification´ for global food security are scrutinized for their engagement with sustainability. This dissertation concludes that genuine sustainable solutions need to respect the various aspects of sustainability, including procedural and distributive justice. Furthermore, it is clarified that general recommendations for agricultural intensification, for instance in Romania, may lead to devastating impacts on biodiversity and ecosystem functions (Chapter 8). This dissertation provides evidence that the beneficial characteristics of the Translvanian farmland are linked to the fine spatial scale of the agricultural mosaic, the amount and distribution of semi-natural elements and the scattered woody vegetation throughout the landscape. Hence, the future of biodiversity depends on human interventions in the ancient cultural landscape. Navigating biodiversity conservation in Southern Transylvania thus needs genuine sustainable solutions, which integrate socially acceptable and ecological meaningful landscape management.
In spite of growing interest in companies’ contribution to sustainable development, the implementation of corporate sustainability, i.e. the integration of environmental, social, and economic issues, is not well understood. This cumulative PhD thesis aims to answer the research question whether sustainability management is only a transitory management fashion, or whether an effective implementation is actually taking place. The thesis consists of five papers, which are either published in refereed academic journals, accepted to be published, or planned to be resubmitted. The papers analyze three important elements of the implementation of corporate sustainability: motivation (why?), organizational units (who?) and management tools (how?). Combining these three elements supplies a framework for discussing the implementation of corporate sustainability management. The results, which are mostly based on surveys of large German companies, reveal that companies predominantly manage corporate sustainability because they seek legitimacy, rather than a competitive advantage, and because they follow acknowledged standards, guidelines, or ratings (institutional isomorphism) – possibly out of uncertainty on how to best handle a concept so complex and novel. Public relations is the organizational unit engaging in sustainability management most strongly, whereas accounting, finance, and management control engage the least. Hence, corporate sustainability is currently not implemented as a crossfunctional approach. Yet, there is indication of a growing strategic relevance of corporate sustainability. This is also reflected in the awareness and application of sustainability management tools, which have been increasing continuously between 2002 and 2010 – especially in terms of integrative tools serving to balance environmental, social, and economic issues. Furthermore, market incentives are gaining in importance over time. The thesis relates these results to management fashion theory. Although there is some indication that sustainability management might in fact be a transitory fashion, an analysis over time reveals an ongoing development of the elements analyzed. Thereby, the thesis demonstrates that corporate sustainability management can be considered more than a management fashion. One implication of the analysis is that both companies and researchers are called upon to foster the implementation of corporate sustainability, with positive incentives, e.g. by markets and consumers, turning out to be promising starting points. As opposed to pressure and expectations by stakeholders, focusing on opportunities might be more suitable to induce actual change of processes, products, services, or even business models in companies. In conclusion, the author hopes to make a significant contribution to the discussion on the implementation of corporate sustainability and to stimulate the development of new theoretical approaches.
Die Verringerung des Material- und Ressourcenverbrauchs ist eine wesentliche Herausforderung nachhaltiger Entwicklung. Bislang standen und stehen politische Maßnahmen zur Energieeffizienz im Vordergrund. Maßnahmen zur Verbesserung der Materialeffizienz gewinnen jedoch verstärkt an Bedeutung. Der Erfolg oder Misserfolg politischer Instrumente im Umwelt- und Klimaschutzbereich wird maßgeblich davon abhängen, ob die Instrumente die Fähigkeit besitzen, eine Entkoppelung von Lebensqualität und Ressourcenverbrauch zu erzeugen. Insbesondere im Rahmen der Ökodesign-Richtlinie, aber auch anderer Instrumente der Europäischen Union, sind Ansatzpunkte zur politischen Gestaltung einer ressourcenleichten Langfristökonomie angelegt. Die Dissertation wird schwerpunktmäßig die Governance-Instrumente im Produktbereich der Europäischen Union behandeln. Die Dissertation folgt der Theorie, dass die Produkte der Industriegesellschaft einzeln mehr oder weniger harmlos, in ihrer Menge jedoch die Quelle fast aller Umweltprobleme sind. Zur Erstellung der Dissertation sieht das spezifische Methodendesign die Anwendung eines Kriterienkatalogs zur Bewertung der Steuerungsinstrumente für Langfristökonomie im Produktbereich vor. Darüber hinaus werden die Hauptakteure in Form von Interviews befragt.
Der Klimawandel wird die Gesellschaft in Zukunft immer stärker beeinflussen. In der Arbeit wird untersucht, wie die direkten Auswirkungen und die daran anschließenden Klimaschutz- und Anpassungsmaßnahmen regionale Konfliktsituationen verändern können. Untersucht werden bisherige Konflikte des Tourismussektors mit anderen nicht-touristischen Akteursgruppen sowie mögliche Konfliktpotenziale durch den Klimawandel am Beispiel der Destinationen Schwarzwald und schleswig-holsteinische Nordseeküste. Qualitative Experteninterviews geben Hinweise darauf, dass besonders die Mitigations- und Anpassungsmaßnahmen, die sonst eher als Konfliktlösung eine Rolle spielen, ein bedeutendes und bisher unterschätztes Konfliktpotenzial bergen. Formelle Verfahren, aber auch eine zusätzliche informelle Beteiligung werden von den Akteuren vor Ort als Konfliktregelungsmechanismen befürwortet.
Responsibility for sustainability is an action guiding concept which relates the abstract norm of sustainability with concrete action contexts. It thereby specifies what bearers of responsibility ought to do. In this thesis, I introduce the concept of responsibility to economic theory, focusing specifically on individual and governmental responsibility for sustainability. Some of the questions I examine are: how should responsibility be distributed among agents? How can agents, who are responsible for several normative aims, solve trade-offs? Do governmental policies affect individuals’ ability to assume responsibility? How can individuals efficiently induce governments to act responsibly? In Paper 1, A utilitarian notion of responsibility for sustainability, I conceptualize and formalize a utilitarian notion of responsibility for sustainability which I then relate to established normative criteria for assessing intertemporal societal choice. I show that responsibility for sustainability can be unambiguously conceptualized in economic models. Furthermore, I affirm that responsibility may provide action guidance even if the aim of sustainability is not feasible. In Paper 2, Verantwortung von Konsumenten für Nachhaltigkeit, I study consumers’ responsibility for sustainability. Particularly, I specify crucial components of this responsibility in order to analyze the relation of consumers’ private and political responsibility. I show that the responsibility for sustainability of consumers comprises three indispensable obligations of which only one concerns consumers’ consumption choices. In Paper 3, Regulation of morally responsible agents with motivation crowding, I focus on the impact of governmental policies on the motivation of an individual to assume moral responsibility. In particular, I study the regulation of a morally responsible individual with motivation crowding in the context of a negative externality. I show that combining consumption taxes with the provision of perfect information is, in many cases, superior to consumption taxes alone. In Paper 4, Endogenous Environmental Policy when Pollution is Transboundary, I examine how individuals which form lobby groups affect the determination of environmental policy when governments seek not only to maximize welfare, but simultaneous maximize support by lobby groups. More specifically, I consider the case in which two countries are linked through transboundary pollution. Environmental policies adopted by self-interested governments may be more stringent than by social welfare maximizing governments. Furthermore, due to the interaction of distortions the space of optimal policies increases: politically optimal tax rates may be too high or too low to optimally internalize the environmental externality.
Traditional farming landscapes have been created in coexistence of rural dwellers and local ecosystems over long time spans, and can be considered tightly coupled ´social-ecological systems´ (SES). Since these landscapes typically embody exceptionally high levels of biological diversity and multiple socio-cultural values, their protection is critical from a sustainability perspective. Due to the pressures of globalization and social change, however, rural livelihoods and farmland biodiversity are at risk. While the focus of research is often on the Southern hemisphere, there are traditional farming landscapes in the former socialist countries of Central and Eastern Europe (CEE) which are equally affected by rapid change, and thus deserve particular attention. Since the institutional breakdown of socialism in 1989, the CEE states have not only been confronted with an unprecedented socio-economic and environmental transition. Their integration into the multi-level governance regime of the European Union (EU) further resulted in the transformation of decision-making structures and competition within the EU common market. In light of the profound changes traditional farming landscapes of Central and Eastern Europe are confronted with, they serve as a valuable source of learning about the institutional design necessary to harmonize socio-economic development and biodiversity conservation within regional social-ecological systems worldwide. This thesis is the result of an in-depth analysis of one traditional farming landscape of Central and Eastern Europe, namely Southern Transylvania (Romania). Based on empirical research involving diverse stakeholder groups, this thesis assessed the impact of EU policy on the area, the institutional features characterizing local-level governance in Southern Transylvania, and the barriers and bridges towards sustainable rural development. This thesis finds that while rural dwellers are highly dependent on smallholder farming and local ecosystems for their livelihoods, Southern Transylvania is currently confronted with a range of structural development barriers. These are likely to be exacerbated by a governance system consisting of historically grounded ´elite social networks´, and by EU policies which often do not fit rural realities. The findings of this dissertation underline that entrenched informal institutions, political will, and historical legacies play a critical role for the governance of traditional social-ecological systems since these ´social system features´ do not only mediate how external policies act on the local level. They may further restrict local adaptive and innovation capacities which, however, are critical for the transformation towards sustainable development. This thesis further finds that there are no blueprint solutions for the design of rural development strategies. Instead, (supra-) national policies should take better account of local socio-economic and cultural particularities.
This PhD dissertation thesis aims to analyse and discuss how a company can interact with its supply chain stakeholders to facilitate the development of sustainable supply chains. The research is based on empirical and conceptual work and contributes to the field of corporate sustainability, supply chain management and its intersection. The thesis develops a conceptual framework to analyse four organisational spheres of interaction (inter, intra, supra and sub) in sustainable supply chain management (SSCM). Thereby, further insights into risk and opportunityoriented approaches of companies to SSCM are provided.