Filtern
Erscheinungsjahr
Dokumenttyp
- Dissertation (126) (entfernen)
Schlagworte
- Nachhaltigkeit (12)
- Biodiversität (4)
- Landwirtschaft (4)
- Sustainability (4)
- Transformation (4)
- Energiewende (3)
- Governance (3)
- Pestizid (3)
- Steuerungsprozesse (3)
- Abwasser (2)
- Agriculture (2)
- Arzneimittel (2)
- Energiepolitik (2)
- Energy Policy (2)
- Ethiopia (2)
- Käfer (2)
- Nachhaltige Entwicklung (2)
- Sediment (2)
- Sustainability Research (2)
- Umweltanalytik (2)
- Umweltbelastung (2)
- Äthiopien (2)
- Ökosystem (2)
- Abwasseranalyse (1)
- Abwasserbelastung (1)
- Abwasserentsorgung (1)
- Abwassermarkierungsstoffe (1)
- Afghanistan (1)
- Agrarpolitik (1)
- Anden (1)
- Antibiotikum (1)
- Artificial Intelligence (1)
- Autonomie (1)
- Autonomy (1)
- Baum (1)
- Bees (1)
- Beweidung (1)
- Bienen (1)
- Biochar (1)
- Biochemie (1)
- Biochemistry (1)
- Biocides (1)
- Biodegradability (1)
- Biodiesel (1)
- Biodiversity (1)
- Biofuel (1)
- Biokraftstoff (1)
- Biologische Abbaubarkeit (1)
- Biomass (1)
- Biomass burning (1)
- Biomasse (1)
- Biosphärenreservat Niedersächsische Elbtalaue (1)
- Biospärenreservat (1)
- Biozide (1)
- Calluna vulgaris (1)
- Citizen Science (1)
- Climate Simulation (1)
- Coastel environment (1)
- Collaborative Initiative (1)
- Corporate Social Responsibility (1)
- Data Mining (1)
- Deschampsia flexnosa (1)
- Deutschland (1)
- Diesel Particulate Filter (1)
- Dignity (1)
- Discourse Studies (1)
- Disease Resistance (1)
- Drahtschmiele (1)
- EU Water Framework Directive (1)
- Ecosystem services (1)
- Ecuador (1)
- Effizienz (1)
- Elbe (1)
- Elektrifizierung (1)
- Elemente (1)
- Energie (1)
- Energieversorgung (1)
- Energiewirtschaft (1)
- Energy Transition (1)
- Entdeckendes Lernen (1)
- Environmental Communication (1)
- Environmental governance (1)
- Erneuerbare Energien (1)
- Ernährungslage (1)
- European Union (1)
- Europäische Union (1)
- Feldversuch (1)
- Fließgewässer (1)
- Food Security (1)
- Foodplain (1)
- Forschungsevaluation (1)
- Fotografie (1)
- Freedom (1)
- Freiheit (1)
- Führung (1)
- Gewässer (1)
- Gewässerbelastung (1)
- Graslandschaft (1)
- Grundschüler (1)
- Habitat (1)
- Harz (1)
- Haushaltschemikalie (1)
- Heidekraut (1)
- Holocene (1)
- Immunity (1)
- Indien (1)
- Individuality (1)
- Individuum (1)
- Institutional Change (1)
- Institutioneller Wandel (1)
- Interdisziplinäre Forschung (1)
- Internationale Organisation (1)
- Internationaler Vergleich (1)
- Jordan (1)
- Kleinbauer (1)
- Klimamodell (1)
- Klimasimulation (1)
- Klimawandel (1)
- Klimaänderung (1)
- Kollaborative Initiative (1)
- Kommunalverwaltung (1)
- Konsum (1)
- Kraftstofffilter (1)
- Krankheitsresistenz (1)
- Kulturlandschaft (1)
- Künstliche Intelligenz (1)
- Küstengebiet (1)
- Lebensraum (1)
- Lebensunterhalt (1)
- Ländlicher Raum (1)
- Makroinvertebraten (1)
- Management (1)
- Meerwasser (1)
- Menschenwürde (1)
- Monitoring (1)
- Nachhaltigkeitsforschung (1)
- Neoinstitutionalismus (1)
- Nichtstaatliche Organisation (1)
- Niederschlag (1)
- Non-Governmental Organisation (1)
- Nordseeküste (1)
- Nährstoffkreislauf (1)
- Oberflächenwasser (1)
- Ozonisierung (1)
- Ozonungsprodukte (1)
- Palaeoclimate (1)
- Paläoklima (1)
- Participation (1)
- Partizipation (1)
- Peru (1)
- Pflanzen (1)
- Photosynthese (1)
- Photosynthesis (1)
- Pleistozän (1)
- Poland (1)
- Polen (1)
- Politische Strategie (1)
- Precipitation (1)
- Produktivität (1)
- Quartär (1)
- Quaternary (1)
- Renaturierung <Ökologie> (1)
- Renewable Energies (1)
- Research Evaluation (1)
- Resin (1)
- Responsibility (1)
- Restoration <Ecology> (1)
- Rohrleitungen (1)
- Samen (1)
- Schädlingsbekämpfungsmittel (1)
- Sedimente (1)
- Software (1)
- Soil quality (1)
- Soziales System (1)
- Stickstoff (1)
- Subsistenz (1)
- Suffizienz (1)
- Summenparameter (1)
- Süßstoff (1)
- Tiermedizin (1)
- Tourismus (1)
- Toxizität (1)
- Transdisciplinarity (1)
- Transition Management (1)
- Transitionsmanagement (1)
- Trinkwasser (1)
- Umweltbildung (1)
- Umweltkommunikation (1)
- Umwelttoxizität (1)
- Unternehmen (1)
- Verantwortung (1)
- Vereinigte Staaten (1)
- Verhalten (1)
- Verwaltung (1)
- Vorland (1)
- Wachstumskritik (1)
- Wald (1)
- Wasseranalyse (1)
- Wasserqualität (1)
- Wasserverschmutzung (1)
- Wastewater (1)
- Water Analysis (1)
- Water Pollution (1)
- Water Quality (1)
- Wehninger Werder (1)
- Wirtschaftlichkeitsanalyse (1)
- Wissensmanagement (1)
- Wärmespeicher (1)
- Wärmespeicherung (1)
- Xylobiont (1)
- agriculture (1)
- analytics (1)
- beetle conservation (1)
- biospere reserve (1)
- climate change (1)
- cultural landscape (1)
- degrowth (1)
- field study (1)
- habitat quality (1)
- heat exchanger (1)
- kleine wirtschaftliche Betriebe (1)
- knowledge management (1)
- ländliche Räume (1)
- macroinvertebrates (1)
- nitrogen (1)
- nutrients (1)
- ozonation products (1)
- pesticides (1)
- pipes (1)
- rural areas (1)
- saproxylic (1)
- sediments (1)
- sewage deposal (1)
- sheep grazing (1)
- small farms (1)
- social-ecological systems (1)
- streams (1)
- subsistence (1)
- sufficiency (1)
- sustainability (1)
- wastewater tracers (1)
- water resources management (1)
- Ökologie (1)
- Ökosystemmanagement (1)
Institut
- Fakultät Nachhaltigkeit (126) (entfernen)
Süßwasserökosysteme stellen für menschliche Gesellschaften verschiedene Ökosystemdienstleistungen wie zum Beispiel Trinkwasser oder Fischressourcen bereit. In der modernen Landwirtschaft kommen große Mengen von Agrochemikalien zum Einsatz, die in die Fließgewässer gelangen und dort zur Schädigung des Ökosystems führen können. Die vorliegende Arbeit trägt wichtige Erkenntnisse zur Abschätzung von Exposition und Effekten bei, die aus dem Eintrag von Pestiziden in Fließgewässerökosysteme resultieren können. Dabei wird eine der umfangreichsten Feldstudien zu den Auswirkungen der Pestizidbelastung in kleinen landwirtschaftlichen Fließgewässern vorgestellt. Die Feldstudie wurde an 29 Bächen in zwei Gebieten Finnlands und Frankreichs durchgeführt und umfaßte die Aufnahme der Zusammensetzung der Invertebratengemeinschaften und eines wichtigen Ökosystemprozesses, dem Blattabbau. Des Weiteren wurde ein Pestizidmonitoring für Verbindungen durchgeführt, die nach den Ergebnissen behördlicher Untersuchungen in ökotoxikologisch relevanten Konzentrationen in den Gewässern vorkommen. Nach der Einleitung (Kapitel 1), werden in den Kapiteln 2-4 neue Methoden zur Erfassung der Pestizidbelastung von Fließgewässern vorgestellt und bewertet. Die Ergebnisse aus der Feldstudie zu den Auswirkungen von Pestiziden werden im Kapitel 5 präsentiert. Im 2. Kapitel wird eine neue Methode zur Erfassung von schwebstoffadsorbierten Pestiziden vorgestellt, bei der die Extraktion mit der beschleunigten Lösemittelextraktion (ASE) durchgeführt wurde. Die Methode zeigte gute Ergebnisse bezüglich Exaktheit und Genauigkeit der Wiederfindung bei der Extraktion 10 polarer und semi-polarer Pestizide verschiedener chemischer Klassen. Bei der Anwendung der Methode auf Schwebstoffproben aus den französischen Bächen wurden Konzentrationen gefunden, die auf Invertebraten toxisch wirken könnten. Zusätzlich wurde in dieser Studie die Geeignetheit von deuterierten Standards der Analyten zur Verwendung als interne Standards während der Extraktion, Aufreinigung und Analytik untersucht. Dabei zeigte sich, daß bei deuterierten Standards mit weniger als 10 Deuteriumatomen Unterschiede im Verhalten zur nicht-deuterierten Verbindung auftreten können. Das folgende Kapitel stellt ein Kalibrationsexperiment zur Ermittlung von Sammelraten für den Chemcatcher® Passivsammler mit polarer Empfängerphase vor. Sammelraten für Passivsammler werden benötigt, um nach der Ausbringung in Gewässern zeitlich-gewichtete Durchschnittskonzentrationen (engl. TWA) berechnen zu können. Für den Chemcatcher® bewegten sich die Sammelraten im Bereich von 0.1 bis 0.5 L pro Tag. Das Kalibrationsexperiment ergab zudem, daß der Chemcatcher® ohne diffusionslimitierende Membran für Felduntersuchungen mit bis zu 14 Tagen Expositionszeit geeignet ist. Die ermittelten Sammelraten werden im 4. Kapitel verwendet, um TWAs für die Freilandexposition des Chemcatchers® in den französischen Bächen zu berechnen. Ferner wird die Leistungsfähigkeit des Chemcatchers® mit zwei weiteren Verfahren zur Erfassung von gewässerbezogener Pestizidbelastung verglichen. Dabei zeigte sich, daß die Probenahme der Wasserphase mit dem Chemcatcher® oder einem ereignisbezogenen Wasserprobenehmer bei polaren und semipolaren Pestiziden ein angemesseneres Bild der Belastung liefert als die Probenahme der Schwebstoffphase. Das 5. Kapitel ist den Auswirkungen von Pestiziden gewidmet und präsentiert eine Risikoabschätzung für die Auswirkungen der Pestizideinträge in die französischen und finnischen Gewässer. Zusätzlich werden potentielle Effekte auf den Blattabbau untersucht und die Anwendbarkeit des „Gefährdete Arten“ (SPEcies At Risk - SPEAR) Index für das länderübergreifende Biomonitoring beurteilt. Das Hauptergebnis der Studie ist, daß Pestizide selbst in Konzentrationen, die bisher als unbedeutend angesehen wurden, sowohl die Struktur der Invertebratengemeinschaften verändern als auch den Blattabbau hemmen können. Des Weiteren war der SPEAR Indikator geeignet, Effekte von Pestiziden über verschiedene Regionen hinweg nachzuweisen. Zusammenfassend weist diese Arbeit nach, daß Pestizide einen wichtigen Störfaktor für Fließgewässerökosysteme darstellen können und liefert Methoden zur Expositions- und Effektabschätzung die in zukünftigen Studien Anwendung finden könnten.
The smallholder-dominated landscapes of southwestern Ethiopia support a unique biodiversity with great importance to local livelihoods and high global conservation value. These landscapes, however, are severely threatened by deforestation, forest degradation and the adverse effects of farmland management regimes. These changes have fundamentally altered the structure of the landscapes and threaten their biodiversity and ecosystem services. Managing biodiversity and related services in such rapidly changing landscapes requires a thorough understanding of the effects of land use change and the reliance of local communities on biodiversity. This dissertation examines woody plant biodiversity patterns and services and presents several recommendations regarding biodiversity and multiple ecosystem services in smallholder-dominated landscapes of southwestern Ethiopia. Using a social-ecological systems approach, the author conducted four studies on the complex interactions of local people and woody plant diversity. First, he investigated the effects of human-induced forest degradation on woody plant species. His results suggest that forest biodiversity has been affected by the combined effects of coffee management intensity, landscape context and history at the local and landscape level. Specifically, richness of forest specialist species significantly has decreased with coffee management intensity and in secondary compared to old growth forests, but increased with current distance from forest edge in both primary and secondary forests. These findings highlight the need to maintain undisturbed forest sites to conserve forest biodiversity. Second, the author examined legacy effects of past agricultural land use on woody plant biodiversity. The results show that historical distance seems to be the most important variable affecting woody plant composition and distribution in farmland sections of the landscapes. The author found evidence for immigration credits for generalist and pioneer species but not for extinction debts for forest specialist species which might be rapidly paid off in farmland. The results suggest not only an unrecognized conservation value of old farmland but also a disturbing loss of forest specialist species. To slow this trend, it is necessary to shift to a cultural landscape development approach and to restore forest specialist species in the landscapes. Third, the author evaluated the supply of potential multiple ecosystem services and the relationships between the diversity of woody plant and ecosystem service in the three major land use types, namely forests with and without coffee management and farmland. The results revealed a high multifunctionality of landscapes and showed that ecosystem services significantly increase with woody plant diversity in all types of land use. These findings suggest that the woody plant diversity and multifunctionality in southwestern Ethiopian landscapes has to be maintained. Fourth, the author explored farmers' woody plant use to assess their dependency on and maintenance of woody plants and also considered the influence of property rights and management in this context. He found that local farmers used 95 species for eleven major purposes from all major land uses across the landscapes. He also found that most of the widely used tree species regenerated successfully throughout the landscapes, including in farmland. Local people felt, however, that their property and tree use rights were limited, especially in forests, and that some of the most widely used plant species, including important timber species, appeared to have been overharvested in forests. The results suggest that many species are important for local livelihoods, but a perceived low sense of property rights also seems to adversely affect the management of woody plants, particularly in forests. By focusing on woody plants and their ecosystem services to local people, this dissertation documents a dramatic loss of native forest biodiversity and rapid changes in the cultural landscapes of southwestern Ethiopia. Overall, the findings suggest the need for preservation of intact forest sites and for cultural landscapes development to safeguard biodiversity and multifunctionality of the landscapes in the future. This, in turn, requires holistic and integrated approaches that involve local people and recognize their basic needs of woody plants and their property rights to foster the management of biodiversity and ecosystem services. Maintaining primary forests in and using cultural landscape approaches to the rapidly changing rural setting of southwestern Ethiopia would also contribute to the global effort to halt biodiversity loss.
Die Energiewende steht im Zentrum aktueller gesellschaftlicher Debatten. Die Frage ist: Wie kann die gegenwärtige Klimakrise aufgehalten und gleichzeitig der Energiebedarf gedeckt werden? Einigkeit besteht darüber, dass eine Strategie zur Energiewende die Umstellung auf erneuerbare Energieträger beinhalten muss. Das Problem ist: Zentrale Begriffe wie "erneuerbare Energieträger " sind uneindeutig und deshalb besonders für naturwissenschaftliche Laien missverständlich. Ihnen wird dadurch die gesellschaftliche Teilhabe an der Debatte erschwert. Wie kann der naturwissenschaftliche Unterricht dazu beitragen, die oben benannten Missverständnisse aufzuklären? Er muss die Schüler dabei unterstützen, die naturwissenschaftlichen Schlüsselprinzipien der verschiedenen Energieträger und darauf aufbauend die Energiewende angemessen zu verstehen. Zu diesem Zweck muss der Unterricht entsprechend strukturiert werden. Welche Leitlinien sowohl die Lehrkräfte der Naturwissenschaften als auch die Entwickler der Unterrichtsmaterialien dabei beachten sollten: Das klärt die vorliegende Studie. Hierfür wird das Modell der didaktischen Rekonstruktion als Forschungsrahmen genutzt. Ausgehend von einem gemäßigt konstruktivistischen Lehr-Lernverständnis werden drei Unterfragen beantwortet: (1) Welche vorunterrichtlichen Vorstellungen bringen Schüler in den Unterricht mit? (2) Welche Vorstellungen haben Wissenschaftler? (3) Welche Unterschiede ergeben sich im Vergleich der Vorstellungen? Für die Beantwortung dieser Fragen wurden in der Erhebung problemzentrierte, leitfadengestützte Interviews mit 27 Achtklässlern geführt und Auszüge aus zwei wissenschaftlichen Gutachten ausgewählt. Mit einer qualitativen Inhaltsanalyse konnten in der Auswertung Inhaltsaspekte identifiziert werden, die Potenzial für die unterrichtliche Vermittlung haben. Mit dem so reduzierten Datenmaterial wurde eine systematische Metaphernanalyse durchgeführt. Damit wurden erfahrungsbasierte Muster hinter den Vorstellungen rekonstruiert. Aus dem systematischen Vergleich der Ergebnisse lassen sich Lernchancen und Lernhindernisse für das Verstehen von naturwissenschaftlichen Hintergründen der Energiewende ableiten. Diese werden in Form von Leitlinien für den naturwissenschaftlichen Unterricht zusammengefasst. Diese Leitlinien können von Lehrpersonen und Entwicklern von Lehrmaterialien genutzt werden, um ein fachlich angemessenes Verstehen der naturwissenschaftlichen Schlüsselprinzipien der Energieträger und der Energiewende zu fördern.
Hochtemperatur-Aquiferwärmespeicher erleichtern Wärmesystemen durch eine saisonale Lastverschiebung die Erschließung und Integration von erneuerbaren Wärmequellen. Ein mittleres Temperaturniveau von >50 Grad Celsius ermöglicht zumeist eine direkte Entladung ohne einen anschließenden Temperaturhub über eine Wärmepumpe. Aufgrund der thermischen Trägheit von ATES-Systemen ist die Berücksichtigung von Lastfalländerungen durch jährlich variierende Lastprofile besonders in der Einschwingphase sinnvoll. Da es bis zu 20 Jahre dauern kann, bis der Aquifer einen quasistationären Zustand erreicht, konnte in Langzeitstudien ein großer Einfluss von unterschiedlichen Lastprofilen auf energetische und finanzielle Simulationsergebnisse nachgewiesen werden. Zur Verbesserung der Investitionsplanung wurde ein Verfahren entwickelt, das sowohl die Prognosefähigkeit als auch die Prognosegenauigkeit von Energiesystem- und Wirtschaftlichkeitsanalysen erhöht, indem über einen wahrscheinlichkeitsbasierten Ansatz (Monte-Carlo-Temperaturschätzung) Normalverteilungsfunktionen für gewünschte Auswertungsgrößen (z.B. Kapitalwert) abgeleitet werden können. Aus 2000 Simulationsjahren wurde über konzeptspezifische Verteilungsfunktionen der wahrscheinlichste Eintrittsfall abgeleitet und zu einem repräsentativen Szenario aggregiert. Das aggregierte Szenario mündet in ein konzeptspezifisches Gleichungssystem, das mit den Freiheitsgraden Energiepreise, Kalkulationszinssatz und Förderanteil gelöst wird. Im Gegensatz zu der etablierten Methode, die Wirtschaftlichkeitsberechnung im Anschluss an eine energetische Systemsimulation anzuhängen, wurde in dieser Arbeit ein holistisches Modell in TRNSYS entwickelt, das für jeden Simulationszeitschritt simultan Energie- und Zahlungsströme berechnet. In dem Modell konnten Verbesserungen in der Prognosegenauigkeit um den Faktor 20 nachgewiesen werden. Mit dem neuen Verfahren kann die Frage der Wirtschaftlichkeit nicht nur mit ja oder nein beantwortet werden, sondern zusätzlich mit der jeweiligen Eintrittswahrscheinlichkeit belegt werden.
Vocational Integration of Refugees - Chances and Challenges of Refugee (Social) Entrepreneurship
(2019)
In recent years, especially since 2015, Germany and other European countries have accepted high numbers of refugees. The social and vocational integration of these refugees and of those yet to come represents a challenge. (Social) entrepreneurship is one means to achieve this goal, to fully tap into the potential of refugees and to give them a chance to make a living in host countries. This dissertation examines the potential of vocational integration of refugees through (social) entrepreneurial activities. It includes a detailed literature review and suggests possible direction in the emerging field of refugee (social) entrepreneurship. This dissertation shows that to foster refugee (social) entrepreneurship, the identification and evaluation of specific and potential needs for support is essential. Incubators in particular have a high potential for supporting refugee entrepreneurs, in part it is possible for them to address some of the challenges faced by this target group, which differ from those of locals or migrant entrepreneurs. More specifically, this dissertation aims to answer two research questions: (1) What are relevant (social) entrepreneurial concepts that can contribute to the vocational integration of refugees? (2) What are the distinct contributions of and challenges faced by refugees when it comes to their vocational integration through (social) entrepreneurial activities? Analyzing select practical cases, this dissertation has several important implications for researchers who seek to bridge the gap between academia and society in the context of refugee entrepreneurship and refugee social entrepreneurship research. The findings presented here are also relevant for practitioners, for example those working at business incubators, who aim to facilitate the vocational and social integration of refugees in general and refugees with entrepreneurial aspirations in particular.
Viable communication systems
(2020)
Society has come to the point that it requires a "Great Transformation" towards sustainability to ensure the viability of the planet for a vital society. The energy transition plays a central role for this transformation. For transforming the patterns of energy production and use in an energy transition as part of the "Great Transformation", this process of change now needs to strengthen its focus on information, communication, and knowledge systems. Human society needs to establish a knowledge system that has the potential to create usable knowledge for sustainability solutions. This requires organizing a communication system that is sufficiently complex, interconnected, and, at the same time, efficient for integrating reflexive, open-ended, inter- and transdisciplinary learning, evaluation, and knowledge co-production processes across multiple levels. This cumulative dissertation contributes to research in this direction by applying a systemic sustainability perspective on the content and organization of communication in the field of research on sustainable energy and the operational level of municipal climate action as part of the energy transition. Regarding sustainability, this thesis uses strong sustainability and its principles as a frame for evaluating the content of communication. Regarding the systemic perspective, the thesis particularly relies on the following theories: (i) the human-environment system model by R. Scholz as an overarching framework regarding interactions between humans and nature, (ii) social systems theory by N. Luhmann to reflect the complexity of society, (iii) knowledge management to consider the human character of knowledge and a practice-oriented perspective, and (iv) management cybernetics, in particular, the Viable System Model by S. Beer as a framework to analyze and assess organizational structures. Furthermore, the thesis leverages the potential of text mining as a method to identify and visualize patterns in texts that reflect prevalent paradigms in communication. The thesis applies the above conceptual and methodological basis in three case studies. Case Study 1 investigates the measures proposed in 16 municipal climate action plans of regional centers in Lower Saxony, Germany. It uses a text mining approach in the form of an Summary interpretation network analysis. It analyzes how different societal subsystems are connected at the semantic level and to what extent sustainability principles can be recognized. Case Study 2 analyzes and reflects paradigms and discursive network structures in international scientific publications on sustainable energy. The study investigates 26533 abstracts published from 1990 to 2016 using a text mining approach, in particular topic modeling via latent Dirichlet allocation. Case Study 3 turns again to the cases of municipal climate action in Lower Saxony examined in Case Study 1. It examines the involvement of climate action managers of these cities in multilevel knowledge processes. Using design principles for knowledge systems, it evaluates to what extent knowledge is managed in this field across levels for supporting the energy transition and to what extent local innovation potential is leveraged or supported. The three case studies show that international research on sustainable energy and municipal climate action in Germany provide promising contributions to achieve a transformation towards sustainability but do not fully reflect the complexity of society and still support a growth paradigm, in contrast to a holistic sustainability paradigm. Further, the case studies show that research and local action are actively engaging with the diversity of energy technologies but are lagging in dealing with the socio-epistemic (communication) system, especially with regard to achieving cohesion. Using the example of German municipalities, Case Studies 1 and 3 highlight the challenges of achieving coherent local action for sustainability and bottom-up organizational learning due to incomplete or uncoordinated multilevel knowledge exchange.
Die Arbeit liefert die Grundlagen zur chemischen Entfernung von Biodiesel aus dem Motoröl, um eine Minderung der Einschleppungsproblematiken beim Einsatz von biogenen Kraftstoffen und Dieselpartikelfiltern zu erzielen. Das Prinzip beruht auf einer wechselwirkenden Beimischkomponenten die eine Azeotropbildung mit Biodiesel einleitet. Eine gaschromatographische Headspace-Screening-Methode diente der Messung von Aktivitätskoeffizienten in Anwesenheit von Biodiesel. Die Ergebnisse dieser Analysen lieferten erste Erkenntnisse welche funktionalen Gruppen eine notwendige starke Wechselwirkung mit Biodiesel besitzen. Die gaschromatographischen Analysen wurden zudem mit Simulationsrechnungen mittels COSMOtherm untermauert. Im Laborversuch haben sich polare Säuren wie Ameisensäure oder Essigsäure als gute Beimischkomponenten erwiesen. Aldehyde, Ketone oder Alkohole sind weniger geeignet. Säuren wirken als Hydrogen Bond Donator und besitzen hohe Aktivitätskoeffizienten mit Biodiesel. Durch die Destillation des gebildeten azeotropen Gemischs kann die Entfernung von Biodiesel aus dem Motoröl bei niedrigen Temperaturen von ca. 180 Grad Celsius bis 190 Grad Celsius realisiert werden. Ohne den Einsatz von Beimischkomponenten liegt die Destillationstemperatur von Biodiesel bei ca. 330 Grad Celsius.
This doctoral dissertation aims to contribute to clarification of the potential of learning for water governance. The goal is to trace and understand the environmental impacts of learning through participation (research aim 1) and adaptive management (research aim 2), and the effect of learning on participation as a governance mode (research aim 3). For this goal, the researcher engages in a predominantly qualitative research design following the case study method. For every specific research aim cases are selected and analysed qualitatively according to conceptual categories and mechanisms which are defined beforehand. Quantitative studies are used to corroborate the results for research aim 1 and 2 in a mixed-method approach to enhance the validity of results. The empirical research context is European water governance, the implementation of the EU Water Framework and EU Floods Directive (WFD, FD) specifically. Eight cases of participatory decision-making across three European countries and five cases of adaptive management in Northern Germany for WFD implementation are examined to identify whether learning in these processes enhanced environmental outcomes. To detect whether governance learning by public officials occurred, the design of participatory processes for FD implementation in ten German federal states is assessed. The findings of research aim 1, understanding learning through participation and its effects on water governance, reveal that participatory planning led to learning through improved understandings at an individual and group level. Learning did, however, hardly shape effective outcomes. In the AM cases (research aim 2) managers and participants of implementing networks improved their knowledge as well as capacities, and spread the results. Nonetheless, environmental improvement was not necessarily linked to ecological learning. Regarding learning about participation as a governance mode (research aim 3) all interviewed public officials in German federal states reported some degree of governance learning, which emerged not systematically but primarily drawing on own experiences and intuition. These findings are condensed into three overarching lessons for learning in water governance: (1) Interactive communication seems to form the overall frame for participant and group learning. Framing of learning experiences turned out to play an important and potentially distorting role, for which professional facilitation and structured knowledge aggregation methods might be an im-portant counterbalance. (2) Learning did not automatically enhance environmental outcomes. It may thus not be an explanatory variable for policy outcomes, but a conditioning or intervening variable related to collective action, motivation for participation, and situating the issue at hand at wider societal levels. (3) The concepts of puzzling and powering might help understand learning as a source for effectiveness in the long-term when complemented with interest-based debates for creat-ing sufficient political agency of policy issues. Learning seen as puzzling processes might instruct acceptance and legitimization for new powering efforts. The perpetuation of learning in systematic ways and structures appears to characterize an alternative to this reflexive and strategic interplay, for which the water-related EU directives provide the basis.
Pestizide werden als Pflanzenschutzmittel im landwirtschaftlichen Bereich und als Biozide z. B. in der Industrie, in Haushalten und Kommunen eingesetzt. Bereits auf den behandelten Flächen und in den angrenzenden Gewässern können Pestizide Abbauprozessen durch u. a. Photolyse unterliegen. Diese Prozesse führen zur Entstehung von Transformationsprodukten (TP), deren Berücksichtigung bei der Umweltrisikobewertung für ein umfassendes Risikomanagement von großer Bedeutung ist. Doch gibt es über die in der Umwelt vorkommenden Transformationsprozesse und die dabei entstehenden TP immer noch Wissenslücken. Darüber hinaus sind die Eintragswege von TP, vor allem von Biozid-TP, in die angrenzenden Gewässer zum Teil unbekannt. Da eine Vielzahl von TP mit unterschiedlich starken ökotoxikologischen Effekten bewertet werden muss, besteht ein großer Bedarf an schnellen und umfassenden Methoden, um die stetig wachsende Anzahl an Chemikalien auf dem Markt erfassen zu können. Das Ziel der vorliegenden Arbeit ist daher, das Verhalten und den Verbleib ausgewählter Pestizid-TP in der aquatischen Umwelt zu analysieren. Zu diesem Zweck wurden unterschiedliche Phototransformationsprozesse von Pestiziden sowie der Eintrag aus Fassaden über Regenwasserversickerungsanlagen (RVA) in angrenzenden Gewässern der Stadt Freiburg untersucht. Schlussendlich erfolgte die Identifizierung der ökotoxikologischen Eigenschaften von 45 Pestizid-TP in einem mehrstufigen Ansatz durch die Kombination experimenteller und computerbasierter Methoden. Inwiefern unterschiedliche Phototransformationsprozesse zu unterschiedlichen TP führen, wurde im ersten Teil der Arbeit durch einen Vergleich der Entstehung von TP durch direkte und indirekte Photolyse der Substanzen Penconazol, Terbutryn und Mecoprop untersucht. Weiterhin wurde der Abbau durch die Bestrahlung mit unterschiedlichen Xenonlampen untersucht. Im zweiten Teil der Arbeit wurde der Eintrag von Bioziden, die in Fassadenanstrichen Anwendung finden, und deren TP über Regenwasserversickerungsanlagen in das Grundwasser untersucht. Dabei wurden qualitative und quantitative Target-Screening-Methoden zum Nachweis und zur Quantifizierung bekannter und unbekannter TP der Biozide Diuron, Terbutryn und Octhilinon (OIT) in der aquatischen Umwelt mittels Flüssigkeitschromatographie mit gekoppeltem Massenspektrometer (LC-MS) kombiniert. Die ökotoxikologischen Eigenschaften von 45 Pestizid-TP wurden im dritten Teil dieser Arbeit in einem mehrstufigen Ansatz untersucht. Insgesamt zeigte sich, dass die Berücksichtigung von TP im Rahmen von Gewässerüberwachung und Risikobewertung eine genauere Abschätzung der Risiken durch Schadstoffe ermöglicht. Die in dieser Dissertation entwickelte Vorgehensweise, bei der TP zunächst im Labor erzeugt und bewertet und anschließend in aquatischen Systemen gezielt analysiert werden, kann einen wichtigen Beitrag zur Regulatorik des Einsatzes und der Zulassung von Pestiziden leisten.
Transforming the International Food Supply – Sustainable Practices in Small Intermediary Businesses
(2021)
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. 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 solution-oriented, 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). Overall, 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, small intermediary businesses could be important agents in food system transformations.
Transformative learning is increasingly set to become an essential component in sustainability transformation. Despite, little has been done to systematically explore the contribution to sustainability transformation. This learning theory developed decades ago independently of sustainability discourses; however, it provides an analytical framework for understanding the learning processes, outcomes and conditions in individual and social learning towards sustainability transformation. Against this background, the following research question arises: To which extent can transformative learning lead to sustainability transformation? This doctoral work aims to explore transformative learning processes, outcomes, and conditions occurring and advancing towards sustainability transformation of the textile-fashion industry in Mexico. Taking an exploratory approach, the methods employed were literature reviews to untangle concepts and to construct theoretical pillars to support the empirical research design and data analysis. For data collection, snowball-sampling techniques were used to explore the practice field of the textile-fashion industry in Mexico. Qualitative interviews were employed to gather data about the learning experiences of actors. Qualitative and quantitative methods were required to perform the respective data analysis, the qualitative codification of interviewees' responses. Analysis of social media content was also utilised to understand the communication and business practices of projects involved in the transformation of the textile-fashion sector. As a result, this work comprises three articles, one a systematic literature review and two empirical research articles, investigating the transformative learning processes of entrepreneurs in the development of sustainability niches. As for the findings of this doctoral work, the use of transformative learning in sustainability transformation requires a careful study of the theory and its conceptual elements. Regarding the case study, transformative learning is inherent in forming and developing sustainability niches as entrepreneurs venture into them: It is individual prior learning, expectations and actions that initiate the path of sustainability transformation while disorienting dilemmas, critical reflection, and discourse accelerate them. Through these stages, it is when individual learning turns into social learning. On the other hand, based on the multi-level perspective, the interplay between the niche, regime and landscape levels generates a space for sustainability transformation and transformative learning.
To counteract species loss and preserve the remaining biodiversity, with its important ecosystem functioning and services essential to human well-being, there is an urgent need to develop promising and long-term conservation strategies. In order to achieve these goals, extensive research to gain a better understanding of the general mechanisms underlying community diversity is of greatest importance. Especially, the identification of intrinsic ecological and distributional species traits is receiving increased attention in ecology and conservation biology research. Depending on the expression of their traits, species perform particular ecosystem functions and respond in a specific manner to environmental conditions. Although insects make up the largest part of animal diversity, the majority of studies on extinctions have mainly focused on vertebrates. Among invertebrates either charismatic taxa or those targeted by conservation laws have been investigated until now (e.g. butterflies or saproxylic beetles). Being highly species-rich and trait-diverse, ground beetles (Coleoptera: Carabidae) should be even more suitable for conducting trait-based analyses. Thus, using ground beetles as a model taxon, four case studies focusing on the analyses of traits form the basis of this doctoral thesis. The work of this thesis was conducted with the aim of gaining general insights on the influence of species traits on ground beetle community compositions, such as habitat occupancy and species vulnerability to extinction, for instance. An important aspect when investigating species traits is the consideration of confounding factors, such as dependent relations between the different traits. Compiling a large dataset of 555 Central European species, the author identified that dependent relations between the six tested traits of ground beetles (distribution range size, habitat specialization, body size, hind-wing morphology, breeding season and trophic level) are highly common. Across all identified dependent trait relations, the relation between body size and hind wing morphology or range size and hind wing morphology showed the strongest significant dependencies. Since the consideration of trait relations is necessary to provide reliable interpretations, all analyses of this thesis tested several traits simultaneously and considered possible trait interactions. Studies on local communities found specific traits characterizing the local species pools of certain habitat types. Here, the species pools of seven different habitat types (coastal, forest, mountain, open, riparian, wetland and special habitat) were used to determine habitat-specific trait filters. The identified traits, characteristic for certain habitat types, were in most cases in accordance with the previous findings on local communities. Across Germany, the species of frequently disturbed habitat types, namely coastal, riparian and wetland habitats were characterized by small body size, high amount of macroptery, intermediate to high habitat specialization, spring breeding, and predatory feeding behavior. The species of stable habitat types (forest, mountain, and open habitats), however, were found to be generally larger in body size and more frequently breeding in autumn, further displaying greater variations in the other traits. The gained knowledge on the habitat-specific filtering of traits improve our understanding of the organization and assembly of communities, and can thereby help to detect alterations in the habitat-specific species pool due to natural or human-induced environmental changes. Furthermore, traits can provide evidence on species occurrences and vulnerability to extinction. Three case studies of this thesis aimed to gain new insights on this topic, through the investigations on the following research questions: (1) Which traits drive species extinction risks of Central European ground beetle species? (2) How traits influence the species occurrences of 28 forest species within a large area in Central Europe? (3) Whether certain traits are related to long-term population trends of the species pool from an ancient forest in northern Germany? The results indicated, that depending on the habitat type and tested species pool, different traits prove to be good predictors for the vulnerability of species. Nevertheless, across different geographical and taxonomical scales, especially species with small range sizes and high habitat specialization faced a greater risk of extinction. Therefore, the two traits distributional range size and habitat specialization emerge as reliable predictors of ground beetles vulnerability to extinction. Interestingly, body size did not display a consistent response; while increasing body size led to higher extinction risk in riparian, wetland and open habitats and large macropterous species showed higher extinction risks across the entire species pool, smaller species showed long-term population declines in an ancient forest.
Gegenwärtige atmogene N-Einträge in die Lüneburger Heide überschreiten die durch den critical-load für Sandheiden definierte Belastungsgrenze von 10-20 kg ha-1 und zeigen den Handlungsbedarf für eine langfristige Erhaltung dieser geschützten Lebensräume. Die traditionelle Schafbeweidung im NSG Lüneburger Heide kann diese hohen atmogenen N-Einträge kompensieren. Das Herdenmanagement minimiert den Nährstoffeintrag über die Exkremente der Tiere, so dass diesem Transfer nur eine geringe Bedeutung zukommt. Die N-Austräge über das Sickerwasser vor, während und nach den Pflegemaßnahmen spielen nur eine untergeordnete Rolle. Extensive Pflegemaßnahmen wie die Mahd und das kontrollierte Brennen sind nicht geeignet die atmogenen N-Einträge langfristig zu kompensieren. Intensiven Pflegemaßnahmen (Schoppern, Plaggen) gelingt dieses, benötigen aber einen zu langen Bearbeitungszyklus, innerhalb dessen kombinierte Verjüngungsmaßnahmen notwenig werden. Die Pflegemaßnahmen haben Auswirkungen auf die N- und P-Vorräte im Heidesystem und führen großteils zu einer P-Verarmung. Das kontrollierte Brennen beeinflusst den P-Haushalt am geringsten. Eine Kombination des Feuereinsatzes mit anderen extensiven Maßnahmen erscheint daher sinnvoll.
Sustainable landscape development is the main goal of decision makers worldwide. Achieving this goal in the long term leads to achieving social, economic and environmental sustainability. Remote sensing has been playing an essential role in monitoring remote areas. This study has employed part of the role of remote sensing in supporting the direction of decision makers towards sustainable landscape development. The study has focused on some of the main elements affecting sustainable environment: land uses, specifically agricultural land uses, water quality, forests, and water hazards such as floods. Three research programs were undertaken to investigate the role of Terrasar-x imagery, as a source of remote sensing data, in monitoring the environment and achieving the previous stated elements. The investigation was intended to investigate the effectiveness of TSX imagery in identifying the cropping pattern of selected study areas by employing a pixel-based supervised maximum likelihood classifier, as published in Paper I, assessment of the efficiency of using TSX imagery in determining land use and the flood risk maps by applying an object-based decision tree classifier as published in Paper II, and determination of the potential of inferential statistics tests such as the two samples Z-test and multivariate analysis, for example Factor Analysis, for identifying the kind of forest canopy, based on the backscattering coefficient of TSX imagery of forest plots, as presented in Paper III. Papers I and II covered two pilot areas in the Lower Saxonian Elbe Valley Biosphere Reserve “das Biosphärenreservat "Niedersächsische Elbtalaue" around Walmsburger Werder and Wehninger Werder. Paper III focused on the Fuhrberger Feld water protection area near Hanover in Germany. The inputs for this research were mainly SAR Imagery and the ground truth data collected from field surveys, in addition to databases, geo-databases and maps. The study presented in Paper I used two filters to decrease speckle noise namely De-Grandi as multi-temporal speckle filter, and Lee as an adaptive filter. A multi-temporal classification method was used to identify the different crops using a pixel-based maximum likelihood classifier. The classification accuracy was assessed based on the external user accuracy for each crop, the external producer accuracy for each crop, the Kappa index and the external total accuracy for the entire classification. Three cropping pattern maps were produced namely the cropping pattern map of Wehninger Werder in 2011 and the cropping pattern maps of Walmsburger Werder in 2010 and in 2011. The study showed that image filtering was essential for enhancing the accuracy of crop classification. The multi-temporal filter De-Grandi enhanced the producer accuracy by about 10% compared to the Lee filter. Furthermore, gathering and utilizing large ground truth data greatly enhanced the accuracy of the classification. The research verified that using sequence images covering the growing season usually improved the classification results. The results exposed the effect of the polarization and demonstrate that the majority of the classifications produced according to the crop calendar had higher total producer accuracy than using all acquisitions. The study demonstrated undertaken in Paper II applied the decision tree object-based classifier in determining the major land uses and the inundation extent areas in 2011 and 2013 using the Lee-filtered imagery. Based on the maps produced for the land uses and inundation areas, the hazard areas due to the floods in 2011 and 2013 were identified. The study illustrated that 95% of the inundated area was classified correctly, that 90% of vegetated lands were accurately determined, and around 80% of the forest and the residential areas were correctly recognized. The research undertaken in Paper III statistically analyzed the backscattering coefficient of the Lee-filtered TSX in some forest plots by the Factor Analysis and two sample Z-test. The study showed that Factor analysis tools succeeded in differentiating between the coniferous forest and the deciduous forest and mixed forest, but failed to discriminate between the deciduous and the mixed forest. On one hand, only one factor was extracted for each sample plot of the coniferous forest with approximately equal loadings during the whole acquisition period from March 2008 to January 2009. On the other hand, two factors were extracted for each deciduous or mixed forest sample plot, where one factor had high loadings during the leaf-on period from May to October, and the other one had high loadings during the leaf-off period from November to April. Furthermore, the research revealed that the two sample Z-test enabled not only differentiation between the deciduous and the mixed forest against the coniferous forest, but also discrimination between deciduous forest and the mixed forest. Statistically significant differences were observed between the mean backscatter values of the HH-polarized acquisitions for the deciduous forest and the mixed forest during the leaf-off period, but no statistically significant difference was found during the leaf-on period. Moreover, plot samples for the deciduous forest had slightly higher mean backscattering coefficients than those for the mixed forest during the leaf-off period.
Urban areas are prone to climate change impacts. Simultaneously the world's population increasingly resides in cities. In this light, there is a growing need to equip urban decision makers with evidence-based climate information tailored to their specific context to adequately adapt to and prepare for future climate change. To construct climate information high-resolution regional climate models and their projections are pivotal. There is a need to move beyond commonly investigated variables, such as temperature and precipitation, to cover a wider breath of possible climate impacts. In this light, the research presented in this thesis is centered around enhancing the understanding about regional-to-local climate change in Berlin and its surroundings, with a focus on humidity. More specifically, following a regional climate modelling and data analysis approach, this research aims to understand the potential of regional climate models, and the possible added value of convection-permitting simulations, to support the development of high-quality climate information for urban regions, to support knowledge-based decision-making. The first part of the thesis investigates what can already be understood with available regional climate model simulations about future climate change in Berlin and its surroundings, particularly with respect to humidity and related variables. Ten EURO-CORDEX model combinations are analyzed, for the RCP8.5 emission scenario during the time period 1970-2100, for the Berlin region. The results are the first to show an urban-rural humidity contrast under a changing climate, simulated by the EURO-CORDEX ensemble, of around 6% relative humidity, and a robust enlarging urban drying effect, of approximately 2-4% relative humidity, in Berlin compared to its surroundings throughout the 21st century. The second part explores how crossing spatial scales from 12.5km to 3km model grid size affects unprecedented humidity extremes and related variables under future climate conditions for Berlin and its surroundings. Based on the unique HAPPI regional climate model dataset, two unprecedented humidity extremes are identified happening under 1.5°C and 2°C global mean warming, respectively SH>0.02 kg/kg and RH<30%. Employing a double-nesting approach, specifically designed for this study, the two humidity extremes are downscaled to the 12.5km grid resolution with the regional climate model REMO, and thereafter to the 3km with the convection-permitting model version of REMO (REMO NH). The findings indicate that the convection-permitting scale mitigates the SH>0.02kg/kg moist extreme and intensifies the RH<30% dry extreme. The multi-variate process analysis shows that the more profound urban drying effect on the convection-permitting resolution is mainly due to better resolving the physical processes related to the land surface scheme and land-atmosphere interactions on the 3km compared to the 12.5km grid resolution. The results demonstrate the added value of the convection-permitting resolution to simulate future humidity extremes in the urban-rural context. The third part of the research investigates the added value of convection-permitting models to simulate humidity related meteorological conditions driving specific climate change impacts, for the Berlin region. Three novel humidity related impact cases are defined for this research: influenza spread and survival; ragweed pollen dispersion; and in-door mold growth. Simulations by the regional climate model REMO are analyzed for the near future (2041-2050) under emission scenario RCP8.5, on the 12.5km and 3km grid resolution. The findings show that the change signal reverses on the convection-permitting resolution for the impact cases pollen, and mold (positive and negative). For influenza, the convection-permitting resolution intensifies the decrease of influenza days under climate change. Longer periods of consecutive influenza and mold days are projected under near-term climate change. The results show the potential of convection-permitting simulations to generate improved information about climate change impacts in urban regions to support decision makers. Generally, all results show an urban drying effect in Berlin compared to its surroundings for relative and specific humidity under climate change, respectively for the urban-rural contrast throughout the 21st century, for the downscaled future extreme conditions, and for the three humidity related impact cases. Added value for the convection-permitting resolution is found to simulate humidity extremes and the meteorological conditions driving the three impacts cases.
Metals fulfill crucial functions in areas as diverse as renewable energy, digitization and life style appliances, mobility, communication, or medicine. In the context of sustainability, achieving a more sustainable metal use means (i) minimizing the adverse effects associated with metal production and use and (ii) sustaining the availability of metals in a way that benefits present and future generations. Urgent need to act to avoid bottlenecks as well as meeting the challenge of possible conflicts of use among those areas of application calls for appropriate strategy making to intervene in the complex field of metal production and use that involves various, often interlinked operating levels, actors, and spatial and temporal scales. This dissertation focuses on strategies as a means to intervene in a system. It pursues the question, which design features could guide future strategy making to foster sustainability along the whole metal life cycle, and especially, how a better understanding of temporalities, i.e. understanding time in a diverse sense, could improve strategy design and help to bridge the assumed "transformation-material gap". This research converges the results from four research studies. A conceptual part explores the role of temporalities for interventions in complex and interlinked systems, which adds to the conceptual basis, on which the empirical part builds up to explore present and future interventions in metal production and use. The research revealed three essential needs that future strategies must tackle: (i) managing the complex interlinkages of processes and activities on various operational levels and spatial and temporal scales, (ii) providing clear guidance concerning the operationalization of sustainability principles, and (iii) keeping activities within the planet’s carrying capacity and embracing constant change as an inherent system characteristic. In response to these needs, the author developed three guidelines with two design features each (one relating to content, and one to the process of formulating and implementing the strategy) to guide future strategy making. The results show that time matters in this respect. If considered in close relation to space and diversely understood in the sense of temporalities, it serves to (i) understand the impact (duration and magnitude) of an intervention, (ii) recognize patterns of change that go beyond establishing linear, one-dimensional connections, and (iii) design interventions in a way that considers the resilience of a system. These findings can contribute to closer considering our understanding of transformation processes towards sustainability in future interventions in metal production and use.
TIME for REFL-ACTION: Interpersonal Competence Development in Project-based Sustainability Courses
(2021)
This dissertation investigates interpersonal competence development in project-based sustainability courses. Visions of a sustainable, safe, and just future cannot be reached by one individual alone. Thus, future change agents need to be able to collaborate and engage with stakeholders, to approach the manifold crises, challenges, problems, and conflicts we are facing together, and to promote and push forward sustainability transitions and transformations. Therefore, this research investigates three project-based sustainability graduate courses by comparing and contrasting teaching and learning outcomes, processes, and environments. A comparative case study approach using a Grounded Theory-inspired research design which triangulates several qualitative methods and perspectives is applied to allow for generalizable insights. Thereby, this dissertation provides empirically-informed insights which are further discussed in relation to selected teaching and learning theories. This leads, first, to a discussion of practical implications within (and beyond) sustainability higher education; and second, provides a theoretical foundation for interpersonal competence development in project-based learning settings – so that educating future change agents can gain momentum. Findings of this research show that embracing conflicts when they occur (i.e. before they provoke cascading effects in the form of further conflicts down-the-road) is an effective strategy to help further develop interpersonal competence. This requires a conflict-embracing attitude. Attitude, in general, seems to be key in interpersonal competence and competence development overall. Self-reflection, if not explicitly required by outside influences (such as instructors), arises naturally from a self-reflective attitude, and is shown to provide the basis for developing interpersonal competence. This research introduces the term "Refl-Action" which stresses the importance of pairing "learning by doing" (as is often the focus in project-based learning settings) with conscious moments of "reflecting about the doing". More specifically, the research presented here identified four learning processes for interpersonal competence development: receiving input, experiencing, reflecting, and experimenting. Based on the empirical data, when the four processes are purposefully combined, following a meaningful sequence attitudes, knowledge, and skills in collaborative teamwork and impactful stakeholder engagement, are fostered (two facets of interpersonal competence). Each of the four learning processes is set in motion through various interactions students engage in during project-based sustainability courses: student-student (labeled "peer"), student-instructor (labeled "deliberate"), student-stakeholder (labeled "professional"), and student-mentor (labeled "supportive") interactions. When these interactions are made explicit subjects of inquiry - i.e. the (inter-)action is linked with (self-)reflection – different learning processes complement one another: Interpersonal competence facets (collaborative teamwork and impactful stakeholder engagement) and domains (attitudes, knowledge, skills) are fostered. While, overall, interactions, processes, and conflicts have been identified as supportive for interpersonal competence development, trust has emerged as another variable inviting further investigation.
The dissertation project focuses on empirically investigating consumers' attitudes, motivations and purchasing decisions regarding sustainable products. The focus on this micro perspective, however, does not reflect consumers' roles within the transformation towards sustainable consumption. Therefore, the present framework paper puts the included papers into a greater context and evaluates the findings on a meta-level by applying an enhanced transition management theory. The analysis underlines that consumers' limited personal capabilities are an underlying reason for unsustainable practices. Therefore, the active engagement not only of consumers, but also of companies is required if the transformation is to be successful. If companies actively support consumers in making sustainable choices, consumers can engage in sustainable consumption with only low cognitive efforts. On this basis, genuine sustainable choices are enabled. The dissertation provides practical implications by highlighting potential measures which will help to promote sustainable products from niches to mainstream. In sum, the dissertation project enhances academic understanding of consumers´ sustainable purchasing behavior and reveals the potential of integrating such insights into the management of transformations towards sustainable consumption.
Poor quality of freshwaters is a widespread problem. The concept of complexity is a particularly promising concept to analyse and address this problem, and public policy problems more generally. The main reason is the concept's strength in unifying structural features of problems within a more comprehensive structural approach to political problem-solving. So far, however, these possible benefits remained hidden given the lack of a clear understanding of complexity, ultimately hampering a systematic analysis of the implications of complexity for solutions and governance strategies. This study aims at strengthening the value of the concept of complexity for systematic comparative analyses of water-related problems and public policies in general. To achieve this goal, this work is to specify the concept of complexity as well as the implications of complexity for solutions and governance strategies, both from a theoretical and an empirical point of view. To this end, five main basic approaches are applied, referring to underlying premises, the role of an interdisciplinary approach, the European Water Framework as an empirical reference point, the integration of practical knowledge, and the focus on external validity. This dissertation provides a detailed operationalisation of complexity related to the dimensions of goals, variables, dynamics, interconnections, and informational uncertainty. It also shows that freshwater pollution-related problems in Germany differ along these five complexity dimensions. This applies to 37 types of pollution-related problems and four clusters of problems, which refer here to tame, wicked, system complexity, and uncertainty problems. This dissertation suggests that relations between complexity and policy delivery can be both positive and negative and vary along dimensions of complexity and policy delivery. Regarding the analysed freshwater pollution problems, this work also shows various effects of complexity on policy delivery, both along the 37 types of problems, and along four clusters of wicked problems. This dissertation suggests a differentiated theoretical approach to define governance for complex problem-solving, demonstrating that the role of diverse institutions, actors, and interactions differs for solutions along five key dimensions of complexity and different management strategies that are information gathering, modelling, using decision-support tools, prioritising of measures, conflict solving, deciding under uncertainty, and being adaptive and flexible.
Since the early 2000s, ecosystem services strongly gained significance as a research topic. However, the temporal dimension of ecosystem services has not been taken into consideration, although this should be the basis for a sustainable long-term management of ecosystems and their services. Therefore, the author presents three articles in this thesis that deal with temporal aspects of ecosystem services. In two of them she also present a proposal for a framework for the classification of ecosystem services based on their temporal dynamics. In this dissertation she differentiates between two types of temporal aspects, both of which have in common that change takes place over a certain period of time. The concepts of transformation, transition and regime shift are used to describe changes in social or ecological systems as a whole, for example the transformation towards a more sustainable society. The temporal dynamics, on the other hand, relate to the temporal changes in ecosystem services themselves. The first article focuses on how the literature on ecosystem services incorporates social and ecological change. The second and third articles deal with the temporal dynamics of ecosystem services. While the second article presents a preliminary framework for categorizing the temporal dynamics of ecosystem services, the third article uses this framework to test how the temporal dynamics of ecosystem services are represented in the literature. Based on the insights from the three articles, the author concludes that most of the studies on ecosystem services only focus on one point in time. One reason for this is that most studies are conducted over a maximum of a four-year time span which does not allow to monitor dynamics over longer time spans.
The importance of a social perspective on the relationships between humans and nature has longbeen acknowledged. The field of social-ecological systems research in particular is striving toachieve a holistic understanding of human-nature relationships by balancing social andecological perspectives. Here I sought to develop a social understanding of the Saxon area inCentral Romania, by exploring aspects of human-nature relationships as seen from theperspective of local people. To this end, I employed the concepts of social-ecological systems(SES), ecosystem services (ES) and cultural landscapes to assess perceptions of locals throughempirical case studies.I first conducted a literature review to acquire an overview of a particular type of human-naturerelationship mediated by non-consumptive use and non-use values (“cultural ecosystemservices”). Second, to isolate and address the interaction from the social system to the ecologicalsystem, I investigated the different ways locals perceived the role of landscapes in SouthernTransylvania. I conceptually mapped these landscape preferences by revealing their potentialland use and management implications. Third, to approach the human-nature relationship fromthe ecological system to the social system, I studied the flow of ES to disaggregated humanbeneficiaries. Specifically, I studied which factors, beyond ecosystem processes and functions,influenced nature derived human well-being from the perspective of potential beneficiaries. Iconceptualised the mediating role of a range of contextual factors underpinning the currentdistribution of ES, with regard to the relation between ES and human well-being. Fourth, inorder to explore an example of bidirectional human-nature relationship, I studied the particularcase of human-carnivore coexistence and the suite of mechanisms shaping it.Despite building throughout this thesis a more complex and in-depth understanding of the humandimensions of the studied system, I chose four main cross-cutting themes to explain the human-nature connection in Southern Transylvania. These four themes may serve as pillars of a sociallyminded understanding, as well as potential research and policy foci. First, the values held bylocals are key for understanding the endemic human-nature relationships and should not beoverlooked in future social-ecological assessments or policy interventions. Second, the culturallandscape of Southern Transylvania is both a physical and virtual space of social-ecologicalinteraction fostering human-nature experiences and social-ecological knowledge integration.Third, the identified diversity of the social system in terms of landscape aspirations and ESbeneficiaries is expanding the range of human-nature connections, but at the same time, may infuture be a source of conflict or disconnection if not managed appropriately. Finally, small-scalefarmers, through their interactions with the land and resultant belief system, play a major role inmaintaining the human-nature relationships, but their values and lifestyle are threatened.
To improve the properties of thermochemical heat storage materials, salt mixtures were evaluated for their heat storage capacity and cycle stability as part of the innovation incubator project "Thermochemical battery" of the Leuphana university Lüneburg. Based on naturally occurring compound minerals, 16 sulfates, 18 chlorides and 5 chloride multi-mixtures, 18 bromides and 5 intermixtures between sulfates, chlorides and bromides were synthesized either from liquid solution or by dry mixing for TGA/DSC screening before continuing the heat storage evaluation with five different measurement setups at a laboratory scale. The TGA/DSC analysis served as a screening process to reduce the number of testing materials for the upscaled experiments. The evaluation process consisted of a three-cycle dehydration/hydration measurement at Tmax=100°C and Tmax=200°C. In case of the bromide samples a measurement of hydration conditions with Tmax=110°C and a water flow at e=18.68mbar, were added to the procedure to detect the maximum water uptake temperature. Also, a single dehydration to a temperature of Tmax=500°C was implemented to observe melting behavior and to easier calculate the samples’ stages of hydration from the remaining anhydrous mass. Materials which showed high energy storage density and improved cycle stability during this first evaluation were cleared for multi-cycle measurements of 10 to 25 dehydration and hydration cycles at Tmax = 100 to 120°C and the evaluations at m=20 to 100g scale. An estimate for the specific heat capacities at different temperatures of the materials which passed the initial stage was calculated from the TGA/DSC results as well. The laboratory scale measurement setup went through five stages of refining, which led to reducing the intended maximum sample mass from m=100g to m=20g. A switch from supplied liquid water to water vapor as the used reactant was also implemented in exchange for improved dehydration conditions. Introducing a vacuum pump for evaporating the water limited the influence of outside heat sources during hydration and in-situ dehydration was enabled as to not disturb the state the samples were settling in between measurements. Baseline calculation from blanc measurements with glass powder and attempts to calculate the specific heat capacity cp of the tested materials by 6 applying the Joule-Lenz-law to the measurement apparatus was another step of method development. The evaluation process of the laboratory scale tests at the final setting consisted of 1 to 5 cycle measurements of in-situ dehydration and hydrations with applied vacuum for t=30 minutes at p~30mbar. Upscaling the sample mass to m=20g allowed for a close observation of different material behaviors. Agglomeration, melting and dissolving of the m=10mg samples during the TGA/DSC analysis can be deducted from the recorded measurement curves and the state of the sample after measurement. However, at laboratory scale the visible volume changes, observed sample consistency after agglomeration and an automatic removal of molten and dissolved sample mass during the measurement allowed for a better characterization and understanding of the magnitude of the actual changes. This was done for the first time, particularly for mixed salts. Of the original number of 62 samples, 4 mixtures which passed the initial TGA/DSC screening namely {2MgCl2+ KCl}, {2MgCl2+CaCl2}, {5SrBr2+8CaCl2} and {2ZnCl2 + CaCl2} were chosen for further evaluation. The multi-cycle TGA/DSC measurements of {2MgCl2+ KCl}, {2MgCl2+CaCl2} and {5SrBr2+8CaCl2} showed an improved cycle stability for all three materials over the untreated educts. Of the four materials {2ZnCl2 + CaCl2} displayed the strongest deliquescence during hydration in the upscaled experimental setup. {2MgCl2+CaCl2} proved to be the most stable material regarding the heat storage density. The {MgCl2} content of the mixture is likely to partially or completely react to {Mg(OH)Cl} at temperatures of T>110°C, which however does not impede the heat storage density. {5SrBr2+8CaCl2} displayed a low melting point in hydrated state, causing a fast material loss. This makes it an undesirable storage material. A lower heating rate may still help to avoid an early melting. The {2MgCl2+KCl} mixture was the most temperature stable of the mixtures showing no melting or dissolving behavior. A reaction of the {MgCl2} component of the mixture to {Mg(OH)Cl} was not observed within the applied temperature range of T=25 to 200°C.
Whereas the extant literature discusses what Sustainability-Oriented Innovations (SOIs) are and why firms develop them, little is known about how they are developed. To enable firms to innovate for sustainability, it is essential to know more about the processes underlying SOI development, which are considered as very difficult, with many firms failing. Drawing on several academic papers and relying on qualitative research methods, the thesis uses the Fireworks model to examine how innovation processes unfold at established small and medium-sized enterprises (SMEs). The main contribution of the thesis is to advance the Fireworks model to the context of SOIs unfolding at SMEs. The findings reveal that SOIs unfold in an emergent, somewhat chaotic way, that duration and outcome are uncertain, that the overall journey is composed of multiple intertwined innovation paths, of which several will likely lead to setbacks. To manage this complex process, the thesis suggests to set four management foci: (1) to create a dedicated organizational unit for exploration, (2) to create conditions allowing intelligent learning for efficient exploration, (3) to carry out in-depth investigation of the related technological innovation systems, and (4) to plan carefully the re-integration of the innovation into the core business for commercialization.
The timber shortage led to large scale afforestations on previously agriculturally used land in Central Europe during the 19th and 20th century. Widespread afforestation programs created recent forest ecosystems (i.e. young forest systems in terms of their development history). Despite the positive effect of increasing the forest area of Central Europe, the ecological effects of these land-use changes on forest ecosystems remain poorly understood. In order to increase the understanding of ecosystem processes in forests, an assessment of conceivable shifts in ecosystem functions caused by former land-use changes and forest management is required. By analysing aboveground growth rates of European beech (Fagus sylvatica L.) in response to environmental change drivers, such as climate extremes and nitrogen (N) deposition, the presented thesis aims to assess the role of land-use and management legacies in modulating present responses to drivers of environmental change. To this end, annual radial growth rates of individual trees were measured in mature beech stands. The investigated stands differed either in their land-use history (i.e. ancient forest sites versus recent forests) or their forest management history (i.e. managed forest sites versus short-term and long-term unmanaged forest sites). Measurements of radial growth rates were complemented by analyses of the fine root systems, soil chemical properties and crown projection areas to gain insights into the mechanisms underlying alterations in tree growth. Within the projects of the presented thesis, shifts in the climate-growth relationships driven by land-use and management legacies were analysed. In addition, land-use legacy mediated differences in the climate-nitrogen-growth relationships were assessed. The key findings are: (I) Soil legacy driven alterations in the fine root systems cause a higher sensitivity of radial increment rates to water deficits in summer for trees growing on recent forest sites than for trees growing on ancient forest sites. (II) Management legacies (in terms of tree release) enhance the sensitivity of beech’s radial growth to water deficits in spring through changes in crown sizes. (III) Interacting effects of spring water deficits and co-occurring high deposition of reactive N compounds lead to stronger radial growth declines in trees growing in ancient forests. This is likely caused by resource allocation processes towards seed production, which is, in turn, mirrored by decreasing radial growth rates. In this context, high N deposition likely boosts mass fructification in beech trees. Overall, it has been demonstrated that the ecological continuity plays a crucial role in modulating both climate sensitivity and the growth response to interacting effects of water deficits and nitrogen deposition in beech trees. The presented thesis identified a trade-off between the climate sensitivity and maximised growth rates within beech trees, depending on forest history. The results show that the growth of beech in ancient, unmanaged beech forests is less sensitive to water deficits than in recent and managed beech forests. Additionally, interacting effects of spring water deficits and N deposition likely increase the reproductive effort of beech trees, particularly in ancient forests. Thus, the results of this thesis once again underpin the uniqueness of ancient, unmanaged beech forests, whose importance for the conservation of biodiversity has been widely acknowledged. In summary, the presented thesis highlights the need to consider the "ecological memory" of forest ecosystems when predicting responses to current and future environmental changes.
European species-rich grasslands are threatened both by land use intensification as well as land abandonment. The studies shown in this thesis tested the possible use of ecological knowledge to ensure hay productivity whilst maintaining diversity of grasslands, with a view to informing ecological restoration. The overall approach was to understand interactions between plants, to study diversity effects on productivity, and mainly investigate how plant functional groups that arrive first in the system can create priority effects that influence community productivity both above- and belowground. A grassland field experiment was established and monitored for four years, in order to verify the effects of manipulating the order of arrival of different plant functional groups, as well as the sown diversity level on productivity and methane yield. The overall findings were: a) sowing legumes first created priority effects aboveground (higher biomass) and belowground (lower root length), plants invested less in roots and more in shoots, b) priority effects were more consistent below than aboveground, c) sown diversity did not affect aboveground biomass, d) the order of arrival treatments indirectly affected methane yield by affecting the relative dominance of plant functional groups. Since the researchers lack information on how legumes and non-legumes interact spatially belowground, (particularly related to root foraging) a controlled experiment was performed, using two grass species and one legume. The identity and location of the neighbours played a role in interactions, and the order plants arrived modulated it. When the focal species (grass) was growing with a legume it generally equated to the same outcome as not having a neighbour. Roots from the focal species grew more toward the legume than the grass neighbour, indicating a spatial component of facilitation. Since these studies involved root measurements, a method study was also conducted to verify how comparable and accurate are root length estimates obtained from different techniques. Results showed that the use of different methods can lead to different results, the studied methods did not have the same accuracy, and the automated methods can underestimate the root length. Overall, the results allow to conclude that different groups of plants arriving before others affected above and belowground biomass, roots may be key drivers during the creation of these priority effects, and interaction outcomes between plants depended on neighbour identity and location, modulated by the order they arrive in. The results suggest that priority effects can be used by sowing different species or plant functional groups at different time to steer a community to a desired trajectory depending on the restoration goal. However, there is a need to test contingency, potential, and long term impacts of such possible tools for restoration.
Agricultural production of smallholder farmers in Myanmar is facing soil fertility degradation and in consequence, crop yields decline due to the imbalances of nutrient supply. In most cases, all above ground biomass is removed from the fields after harvesting the crops and during land preparation for the next crop. Higher temperatures also stimulate the higher mineralisation rates and released mineral nutrients are lost from fallow lands before sowing the next crops. Regarding the addition of mineral fertilizers, except for cash crops, farmers are reluctant to apply fertilizers for the crops that are sown for household’s self-sufficiency. In the Dry Zone, irrigated agriculture is available in recent years and farmers could overcome water scarcity through irrigation. With the availability of irrigation water, farmers could prolong the cropping period, nevertheless crop yields are decreasing year by year. In recent decades, research findings are indicating the benefits of biochar application for soil fertility improvement and food security. Smallholder farmers can produce biochar from agricultural by-products such as pigeon pea stems, cotton stems and rice husks by using biochar stoves. Large-scale production is possible by producing both biochar and thermal energy simultaneously, such as getting rice husk biochar and producing thermal energy by burning rice husks. By those means, environmental pollution due to the smokes from stubble burnings and the health hazards from smokes arise from kitchens can also be reduced. Present research was conducted to test the effects of the application of biochars produced from different crop residues together with NPK fertilizers on crop yields and soil properties in the rice-chickpea-cotton cropping system of the Central Dry Zone area of Myanmar during 2012 and 2013 cropping seasons at Shwe Daung Farm, Mandalay Division, Myanmar. Effects of biochar applications in combination with NPK fertilizers were compared with NPK fertilizer (without biochar) application and the control (without biochar and NPK fertilizers). Biochars used in the experiments were produced from three kinds of locally available raw materials (rice husk, rice straw and, pigeon pea stem) at temperature above 550°C by using a kiln made from a 200-Liter diesel barrel. Field experiments were conducted on sandy loam soil in the Central Dry Zone of Myanmar. After harvesting rice in 2012, chickpea was sown without application of both organic and inorganic fertilizers. After harvesting chickpea in 2013, cotton was sown on the same experimental plots. Treatments were rice husk biochar (Rh) 20 Mg ha-1 + NPK fertilizers; rice straw biochar (Rs) 20 Mg ha-1 + NPK fertilizers; pigeon pea stem biochar (Ps) 20 Mg ha-1 + NPK fertilizers; rice husk biochar and farmyard manure mixture (Rh biochar + FYM) 10 Mg ha-1 + NPK fertilizers; NPK fertilizers (without biochar); and the control (without fertilizer and biochar). Biochar weights represented fresh biochar weights. Equal rate of NPK fertilizers were applied in all treatments. However, fertilizer rates were different with respect to the crops. In rice experiment, 100:50:50 kg ha-1 rate of Urea (N): Triple Super Phosphate (P): Muriate of potash (K) was applied. In cotton experiment, 100:30:117 kg ha-1 rate of Urea (N): Triple Super Phosphate (P): Muriate of potash (K) was applied. Crop growth data, yield component data and yield data of each treatment were recorded. Soil samples from topsoil (0-0.2 m) were taken before starting the experiments, after harvesting rice and cotton, respectively, and analysed. A biogeochemical model, denitrification decomposition (DNDC) model, was used to estimate soil organic carbon storage and greenhouse gas emissions during crop growing seasons and to quantify the long-term impact of biochar applications on rice, chickpea and cotton yields.The results from soil analyses indicated that although initial soil pH was at 8.0 and pH values of biochars ranged between 8.0 and 10.0 soil pH after two years of biochar application did not increase. pH values were below 8.0. That value was lower than initial soil pH. That could be due to the effect of the change of cropping system from upland to lowland rice cultivation and the effects of biochar additions to the alkaline sandy loamy soil of the experimental site. Although total exchangeable cation value was not significantly different among the treatments, compositions of major cations were significantly different among the treatments. Exchangeable potassium increased in Rs biochar + NPK applied soils. Exchangeable sodium increased in control, and conventional NPK fertilizer applied soils. Reduction of soil bulk density from 1.8 g cm-3 to 1.6-1.7 g cm-3 occurred in biochar treatments compared to control and conventional NPK fertilizer application treatments. Positive changes of total carbon and total nitrogen of soils were found in biochar treatments compared to control and conventional NPK fertilizer application. Application of pigeon pea stem biochar + NPK fertilizers showed the highest crop growth and the highest yield in rice. The highest chickpea yield was obtained from the plot that applied rice husk biochar + NPK fertilizers. Cotton crop growth and yield was the highest in rice husk biochar and farmyard manure mixture + NPK fertilizer application. The lowest crop growth and yield was obtained from the control in cotton. The results of this study suggested that biochars from different biomass materials had different effects on soil properties and crop yields under different growing conditions and cultivated crops. Although the applied biochars had a high pH, soil pH did not increase after biochar applications. The growth and yield of tested crops were higher than that of the control and conventional NPK fertilizer application. Rice husk biochar and farmyard manure mixture + NPK fertilizer application can be assumed as a suitable soil amendment application under upland crop cultivation. Pigeon pea stems biochar + NPK fertilizers should be applied in rice cultivation. Rice husk biochar + NPK fertilizers and rice husk biochar-farmyard manure mixture + NPK fertilizers showed as the appropriate biochar soil amendments for the study area compared to rice straw biochar + NPK fertilizers and pigeon pea stem biochar + NPK fertilizers. Application of these biochars increased total exchangeable cations, reduced bulk density, increased organic carbon, regulated soil pH and, can easily be accessed by smallholder farmers by promising crop yields for sustainable agricultural production. Rice straw biochar + NPK fertilizers and pigeon pea stem biochar + NPK fertilizers also showed positive influences on soil fertility and crop growth. However, extensive application of those biochars might require large-scale productions and distributions. To obtain the detail information regarding the impact of biochar application on the agro-ecosystem and surrounding atmosphere, further research activities may need to carry out under different agricultural production conditions. When model fitness was tested, it was found that DNDC model was fit for the simulation of crop yields and soil organic carbon under the conditions of the experimental site. Simulation of soil organic carbon dynamics and crop yields for 30 years and 50 years after the addition of biochars in combination with NPK fertilizers showed that such applications could maintain the crop yields at the same level up to 50 years. That could maintain soil organic carbon at a level higher than conventional NPK fertilizer application. Regarding the simulation of GHGs emissions, the model simulated nitrous oxide emission close to actual emissions of agricultural soils of Myanmar. Simulated CH4 emissions from control and conventional NPK fertilizer application variant were consistent with the well-known emissions of Myanmar rice fields. To confirm the accuracy of simulated CH4 emissions from biochar applied soils, it may need field investigations and validations of model results. Simulated effects of rice husk-, rice straw- and pigeon pea stem fresh biomass applications and that of rice husk-, rice straw- and pigeon pea stem biochar applications on rice, chickpea, cotton yields and soil organic carbon (SOC) were compared. Objective of this simulation was to compare the effects of fresh biomass-applications and the application of biochars produced from the same biomass on crop yields and SOC by using DNDC model. The results showed that simulated rice yields of rice husk biochar and rice straw biochar applications were 33% and 31%, respectively, higher than that of pigeon pea green manure applications. However, simulated rice yield from pigeon pea stem biochar application was 4% higher than that of iv pigeon pea stem green manure application. Simulated chickpea yield from pigeon pea green manure treatment was the highest among all of biochar and biomass applications. Simulated cotton yields obtained from fresh biomass applications were lower than that of biochar applications. In estimating the future yields, all crop yields from rice husk and rice straw biomass applications were lower than that of rice husk and rice straw biochar applications in the initial year of simulation. However, in the following years, the yields remained at the same level up to the end of simulated years. In pigeon pea stem green manure application, crop yields were higher than the other treatments since the initial year up to the end of simulated years. Simulated SOC was lower in fresh biomass applications compared to biochar applications.
The effects of habitat fragmentation and land use changes are usually studied by relating patterns of genetic diversity and differentiation to environmental factors, habitat history, landscape structure, or to a combination thereof. However, these three drivers are rarely addressed simultaneously. In addition, these studies are usually carried out in conservation-driven contexts, and therefore tend to concentrate on hyper-fragmented landscapes and on rare or endangered species. However, how habitat fragmentation and land use affect widespread species in more typical landscapes has not been fully investigated. This thesis addresses these two gaps. Abax parallelepipedus, a flightless ground beetle with low dispersal power, was used as a model species to test how environmental factors, habitat history, and landscape structure affect genetic diversity and genetic differentiation in three study regions located across Germany. Although all of the study regions represent fairly typical rural landscapes for central Europe, each consisting of a complex matrix of land uses, they differ from one another in terms of environmental factors, habitat history, and landscape structure, and thus can serve as three test cases. In the first stage of the work, the investigator identified polymorphic microsatellite loci which could potentially be used to study genetic diversity and differentiation in A. parallelepipedus. She then developed PCR and genotyping protocols for two suites of loci, in the end selecting to use the set of 14 fully multiplexed loci for the study. After having developed the needed study system, she genotyped over 3300 beetles from 142 study sites. In her investigation of how environmental factors and habitat history affect genetic diversity and genetic differentiation, and found that genetic diversity was being driven by variables that could be related to population sizes rather than by habitat history. She also did not find evidence of an influence of habitat history on the genetic differentiation patterns. Although populations of A. parallelepipedus in the past were probably smaller due to deforestation, they apparently remained large enough to prevent rapid genetic drift. In addition, the researcher carried out a landscape genetics analysis of the genetic differentiation patterns found in each of her study regions, in which she examined the relationship between genetic differentiation and landscape structure. She tested whether she could find patterns of isolation by distance, isolation by resistance, or isolation by barriers in the study regions. No effects of land use or of fragmentation were found. Based on the importance of population sizes found in the previous study, combined with the beetle's known avoidance of non-wooded areas and its inability to cross roads, the investigator concludes that although there is probably little gene flow across the study regions, large population sizes are preventing the rapid development of genetic differentiation. Models simulating the development of genetic differentiation over time in populations of different starting sizes support this conclusion.
The transition of our energy system towards a generation by renewables, and the corresponding developments of wind power technology enlarge the requirements that must be met by a wind turbine control scheme. Within this thesis, the role of modern, model-based control approaches in providing an answer to present and future challenges faced by wind energy conversion systems is discussed. While many different control loops shape the power system in general, and the energy conversion process from the wind to the electrical grid specifically, this work addresses the problem of power output regulation of an individual turbine. To this end, the considered control task focuses on the operation of the turbine on the nonlinear power conversion curve, which is dictated by the aerodynamic interaction of the wind turbine structure and the current inflow. To enable a power tracking functionality, and thereby account for requirements of the electrical grid instead of operating the turbine at maximum efficiency constantly, an extended operational range is explicitly considered in the implemented control scheme. This allows for an adjustment of the produced power depending on the current state of the electrical grid and is one component in constructing a reliable and stable power system based on renewable generation. To account for the nonlinear dynamics involved, a linear matrix inequalities approach to control based on Takagi-Sugeno modeling is investigated. This structure is capable of integrating several degrees of freedom into an automated control design, where, additionally to stability, performance constraints are integrated into the design to account for the sensitive dynamical behavior of turbines in operation and the loading experienced by the turbine components. For this purpose, a disturbance observer is designed that provides an estimate of the current effective wind speed from the evolution of the measurements. This information is used to adjust the control scheme to the varying operating points and dynamics. Using this controller, a detailed simulation study is performed that illustrates the experienced loading of the turbine structure due to a dynamic variation of the power output. It is found that a dedicated controller allows wind turbines to provide such functionality. Additionally to the conducted simulations, the control scheme is validated experimentally. For this purpose, a fully controllable wind turbine is operated in a wind tunnel setup that is capable of generating reproducible wind conditions, including turbulence, in a wide operational range. This allows for an assessment of the power tracking performance enforced by the controller and analysis of the wind speed estimation error with the uncertainties present in the physical application. The controller showed to operate the turbine smoothly in all considered operating scenarios, while the implementation in the real-time environment revealed no limitations in the application of the approach within the experiments. Hence, the high flexibility in adjusting the turbine operating trajectories and structural design characteristics within the model-based design allows for efficient controller synthesis for wind turbines with increasing functionality and complexity.
This dissertation contributes to research on generating actionable knowledge for coastal governance to enhance the resilience of coastal social-ecological systems (SES) to climate change. It does this by providing theoretical, methodological and empirical insights on three research questions (RQs). These are: (1) what is a more actionable concept for applying the concept of resilience in coastal governance?; (2) what methods and approaches are suitable to generate actionable knowledge for coastal governance?; (3) what obstacles to knowledge co-production exist for early-career researchers (ECRs) and how can they be overcome? The RQs are addressed in five publications. For answering RQ1, the dissertation applies a research synthesis to bring together common themes and challenges documented in resilience, climate change and environmental governance literature. For answering RQ2, different methods and approaches for generating actionable knowledge are proposed and tested using a case-study in the SES of Algoa Bay, South Africa. These include (i) the analysis of stakeholder agency; (ii) the application of a stakeholder analysis; and (iii) the combination of a capital approach framework, and fuzzy cognitive mapping. Finally, for answering RQ3, the thesis provides a perspective on the obstacles that especially ECRs face, and actions that are needed to create the conditions under which knowledge co-production processes can be successful. This is done by applying a multi-method approach combining an online survey and workshop targeted at ECRs in the marine sciences. Key findings suggest that system and transformative knowledge are particularly important when applying the concept of resilience in coastal governance to generate actionable knowledge. The different methods and approaches that are proposed and tested contribute to generating both system and transformative knowledge. Firstly, they provide an overview of the capacities of different stakeholders to act, shed light on current collaboration and knowledge exchange, and enable the identification of different governance processes for coastal governance and climate change adaptation (system knowledge). Secondly, results have implications for how to improve knowledge exchange and identify leverage points that can enhance overall governance performance, thus providing recommendations on actions and processes that can enhance climate resilience in the case-study area (transformative knowledge). It is also highlighted how knowledge co-production can contribute to generating system and transformative knowledge together with stakeholders, and what actions are needed to build the capacities to translate knowledge into action. Additionally, the findings of this dissertation put forward actions that are needed at different organisational levels of the academic system to facilitate knowledge co-production processes with stakeholders involved in coastal governance. The results of this dissertation have implications for stakeholders and decision-making in the case-study area, as well as for environmental governance, climate change adaptation and broader sustainability research. Implications for stakeholders include recommendations for implementing formal commitments to share climate information across levels and sectors, establishing the role of information providers in the municipality, and reinforcing human capital within the local municipality in Algoa Bay. Findings also suggest the need for a more integrated approach to climate change adaptation in coastal planning and management frameworks. It also suggests that the conservation of environmental assets presents an important bottleneck for resilience management and needs to be further prioritised within decision-making. Implications for research include the applicability of methods beyond the context of this dissertation; a more actionable concept for approaching resilience in (coastal) governance systems; and a more critical reflection on how transformative research is conducted, and what academic foundation is needed so that it can fulfil its societal goal.
The research aims to assess the sustainability of rural electrification efforts based on off-grid photovoltaic (PV) systems in three Andean countries: Chile, Ecuador, and Peru. Although deployment of off-grid PV solutions for rural electrification began in the early 1990s in the Andean region, most of the projects turned out to be unsustainable and did not last. Prior efforts have addressed the different issues and barriers that plagued these projects and inhibited their sustainability. However, these prior analyses were mostly quantitative; systematic qualitative evaluations have been scarce. In this thesis, the researcher addresses the following research question: "Are the rural electrification programs (based on off-grid PV Systems) in the Andean countries sustainable?" In order to answer this research question, he conducted an exhaustive qualitative document analysis complemented by semi-structured expert interviews. The interviewees included experts from different ministries, project managers from leading Non-Governmental Organizations (NGOs), public and private companies ' representatives, supervisors, and researchers. Although the author also describes several relevant PV-based electrification efforts in the Andean countries, the research was aimed at providing an overall picture of the rural electrification efforts in these countries, rather than measuring the success or failure of specific projects. The gathered information allowed me to assess the sustainability of rural electrification efforts in the Andean countries. This assessment was based on a set of indicators corresponding to the four dimensions of sustainability considered in this thesis: institutional, economical, environmental, and socio-cultural. It was found that Ecuador and Chile have consistently failed to ensure mechanisms for the operation and maintenance of the deployed off-grid systems, which has made these solutions in poor Chilean and Ecuadorian communities inevitably unsustainable. Although Peru has adopted a cross-tariff scheme, the Peruvian case shows that ensuring the funding of off-grid PV solutions is not enough. Peruvian officials appear to be unaware of the importance of local participation (local values and lifestyles are constantly disregarded) and most of the projects have been designed without the participation and engagement of the communities, which has often led to project failures and payment defaults. Although each country has its particular challenges, it was found that the three Andean countries have consistently neglected the importance of strong formal institutions with a flexible and decentralized structure, which in turn significantly compromised the rural electrification effort in these countries.
This PhD thesis examines the connections between sustainability knowledge management (SKM) and sustainability management tools in small and medium-sized enterprises (SMEs). While previous literature has established that knowledge is essential for the application of sustainability management tools, the effects of such tools on knowledge management are under-researched in the sustainability context. Drawing on multiple academic papers and utilizing various research methods, including a systematic literature review, several quantitative surveys and a multiple case study approach, the thesis systematically examines how such tools can facilitate the identification, acquisition, conversion, application and retention of sustainability knowledge, and potentially lead to the improvement of SKM effectiveness in SMEs. Furthermore, it examines how support functions for sustainability management tools and SKM correspond with each other. The findings reveal that sustainability management tools facilitate the SKM processes (identification, acquisition, conversion, application and retention), and align with the support factors (e.g. top management support, shared vision, employee qualifications) to advance SKM in SMEs. Particularly, such tools permit the institutionalization of sustainability knowledge into the daily routines and practices in SMEs. Additionally, tools create a support structure for SKM, embedding and preserving sustainability knowledge in documents, policies, procedures and norms for an enterprise´s collective knowledge for sustainability management. The thesis concludes with complementing areas of future research and offers practical implications for SME management.
This thesis deals with sustainability in African Higher Education Institutions (HEIs) and the influence of language in achieving sustainable development. Several authors highlight the existing imbalance of sustainability research in higher education, with most publications focusing on the so-called Global North. Little is known about sustainability in the so-called Global South, and in African educational institutions in particular. The first article of this thesis investigated existing sustainability activities in African HEIs. Rather than focusing on the shortcomings, the paper took a positive stance, opposing the predominant language of deficits in research on Africa. In the Delphi study conducted, 32 experts from 29 HEIs in 16 African countries described the sustainability activities they are engaging in. Experts provided information about their experiences in their respective HEI, while language and culture emerged as areas in need of further research. The second article therefore focused on the relationship between language and education for sustainable development in African educational institutions, and systematically reviewed scholarly literature regarding this connection. Authors of the reviewed 33 papers approached this connection mainly on a theoretical and philosophical level, focusing on education and Africa as a whole rather than specified forms of education in specific countries. The third article examined the views of Tanzanian higher education students and graduates regarding language and sustainability. Participants explained how they integrate sustainability and the Sustainable Development Goals (SDGs) into their research and how they approach translations in the process. In the ensuing interviews, participants estimated that only a fraction of people outside of academia are aware of sustainability and the SDGs, rendering the achievement of target 4.7 unlikely. This thesis therefore contributes to a better understanding of the current challenges in implementing sustainability and the SDGs in African educational institutions. It highlights the need to integrate (local) African languages in order for sustainability activities as well as the SDGs to be successful.
Siliziumorganische Substanzen sind aus dem Alltag kaum wegzudenken. Sie kommen in vielfältiger Form vor und finden durch ihre Stabilität in vielen Produkten des Haushalts und der Industrie Anwendung. Eine Freisetzung in die Umwelt ist unvermeidbar. Siliziumorganische Substanzen konnten bereits in allen Umweltkompartimenten (Luft, Wasser, Boden) analytisch nachgewiesen werden. Welche Risiken von dieser Stoffgruppe ausgehen, ist noch nicht abschließend geklärt. Dennoch gibt es Hinweise auf negative Auswirkungen auf Mensch und Umwelt. Deshalb sollten Strukturen in siliziumorganischen Substanzen untersucht werden, die einen Abbau in der Umwelt begünstigen, um die Akkumulation dieser Stoffe in der Umwelt zu verringern. Dafür wurden diverse biotische und abiotische Abbautests mit unterschiedlichen siliziumorganischen Substanzen durchgeführt. Der Fokus der vorliegenden Arbeit lag vor allem in der biologischen Abbaubarkeit der Substanzen. Es wurden die Organisation for Economic Co-operation and Development (OECD)-konformen Tests Closed-Bottle-Test (CBT, OECD 301D) und Manometrischer Respirationstest (MRT, OECD 301F) durchgeführt. Die Hydrolysierbarkeit wurde mithilfe des Hydrolysetests OECD 111 bei unterschiedlichen pH-Werten untersucht. Bei bestimmten Substanzgruppen ohne biologischen Abbau wurde das Verhalten der Substanzen bei Bestrahlung mit verschiedenen Bestrahlungsquellen untersucht. Die Analyse der Primärelimination der siliziumorganischen Substanzen erfolgte je nach Substanzeigenschaften mithilfe der Hochleistungsflüssigkeitschromatografie gekoppelt mit einem Spektrometer mit ultraviolettem und sichtbarem Licht (HPLC-UV/Vis) oder der Gaschromatografie gekoppelt mit einem Massenspektrometer (GC-MS). Die Transformationsprodukte wurden hingegen mithilfe der Flüssigkeitschromatografie gekoppelt mit einem Mehrfach-Massenspektrometer (LC-MSn) analysiert. Für eine umfassende Bewertung des biologischen Abbaus von siliziumorganischen Substanzen wurden ein Vergleich mit analogen Kohlenstoffverbindungen und eine Aufstockung mit Daten aus der Datenbank der Europäischen Chemikalien Agentur (ECHA) durchgeführt. Die Gruppierung der Substanzen nach ihren Strukturmerkmalen wurde hinzugezogen, um Rückschlüsse auf die Abbaubarkeit zu ziehen. Eine besser biologisch abbaubare Grundstruktur brachte für die Benzenderivate keine Verbesserung der biologischen Abbaubarkeit. Dennoch hatte die Einführung von +M-Gruppen am Aromaten einen positiven Einfluss auf die Geschwindigkeit und den Grad des photolytischen Abbaus. Die Bestrahlungsquelle hatte ebenfalls einen deutlichen Einfluss auf die Eliminierungsrate während des Photolyseexperiments. Mit einer Veränderung der Wellenlängen in den kurzwelligen Bereich und der daraus resultierenden energiereicheren Strahlung konnten die Substanzen schneller und teilweise vollständig primär eliminiert werden. Bei allen Abbaupfaden hatte die Hydrolyse eine entscheidende Rolle und wurde als einer der Hauptabbauprozesse charakterisiert. Bei einer Verbindung wurde im Nachgang an die biotischen und abiotischen Abbautests eine ausführliche Aufklärung der elf gebildeten Transformationsprodukte vorgenommen. Um den Einfluss von Silizium in organischen Substanzen auf die biologische Abbaubarkeit zu untersuchen, wurde der direkte Vergleich von siliziumorganischen Substanzen und deren Kohlenstoffanaloga im CBT durchgeführt. Dabei hat sich gezeigt, dass drei von fünf Kohlenstoffverbindungen und keine siliziumorganische Verbindung als leicht biologisch abbaubar eingestuft werden konnten. In allen bis auf einen Fall konnten für die Kohlenstoffverbindungen höhere Abbauraten im CBT beobachtet werden. Die Hydrolyse wurde als erforderlicher Schritt vor dem biologischen Abbau von siliziumorganischen Substanzen identifiziert. Das siliziumfreie Produkt der Hydrolyse bestimmte den Grad des biologischen Abbaus. Die gute biologische Abbaubarkeit der einen siliziumorganischen Verbindung resultierte aus der leicht hydrolysierbaren Silizium-Stickstoff-Bindung und der leichten biologischen Abbaubarkeit des siliziumfreien Hydrolyseproduktes. Die siliziumhaltigen Reaktionsprodukte der Hydrolyse waren nicht biologisch abbaubar. Bioabbaudaten aus eigenen Experimenten, aus vorhergehenden in der Arbeitsgruppe durchgeführten analogen Arbeiten und aus der ECHA-Datenbank wurden zusammengetragen, um einen Datensatz zu generieren. Die 182 Substanzen des Datensatzes wurden hinsichtlich ihrer Struktur gruppiert, um allgemeine Erkenntnisse für die biologische Abbaubarkeit von siliziumorganischen Verbindungen abzuleiten. Es gab Gruppen mit Substanzen, die überhaupt nicht biologisch abbaubar waren (z. B. zyklische, lineare und verzweigte Siloxane). Gruppen, die Substanzen mit Ethern, Estern, Oximen, Aminen und Amiden enthielten, waren hydrolyseanfällig, sodass auch leicht biologisch abbaubare Zwischenprodukte gebildet werden konnten. Die siliziumfreien Hydrolyseprodukte waren meist biologisch abbaubar, während die siliziumhaltigen Hydrolyseprodukte persistent waren. Allgemein hat sich gezeigt, dass Modifikationen am Molekül einen positiven Einfluss auf die Abbaubarkeit haben können. Beispielsweise können Heteroatome eine Veränderung der Polarität bzw. der Elektronendichte hervorrufen, was die Photolyse- und Hydrolysefähigkeit und folglich auch den Bioabbau zum Positiven verändern kann. Das Einführen solcher Heteroatome oder funktioneller Gruppen in Polysiloxanketten kann demnach ein vielversprechender Ansatz für leichter abbaubare siliziumorganische Verbindungen sein. Nicht abbaubare Stoffe sollten vermieden werden, wenn sie nach ihrer Verwendung in die Umwelt gelangen.
Die Agenda 2030 der Vereinten Nationen und diverse daraus abgeleitete Nachhaltigkeitsstrategien setzen einen zeitlich fest definierten Rahmen bis in das Jahr 2030. Für die Umsetzung dieser Strategien sind zwei Aspekte entscheidend - ein fundiertes inhaltliches Verständnis von politischer Strategie und ein darauf aufbauendes praxistaugliches Instrument, das den politischen Strategen bei einer erfolgreichen Umsetzung und Implementierung einer Strategie unterstützt. Diese Arbeit möchte zu beiden Aspekten einen Beitrag leisten. Zum einen wird aus der Zusammenführung von Theorie und Praxis die Natur des inhaltlichen politischen Strategiebegriffs erforscht. Zum anderen wird darauf aufbauend ein praxis- und erfahrungsorientiertes Anwendungsmodell entwickelt, das typische potentielle Herausforderungen und entsprechende potentielle Handlungsoptionen je Strategieabschnitt benennt. Durch die Subsumierung von Erfahrungswissen unterstützt das Modell dabei vor allem das praktische Urteilsvermögen des politischen Strategen bei der Erreichung politikstrategischer Ziele. Um zu dem praxisrelevanten Anwendungsmodell zu gelangen ist es notwendig, sich zuvor Klarheit über die besonderen Anforderungen und Herausforderungen des speziellen politischen Strategiebegriffs zu verschaffen. Die politische Umwelt mit ihren spezifischen Mechanismen unterscheidet sich fundamental von den bisher bekannten Strategiefeldern Militär und Betriebswirtschaft. Da eine Strategie immer die konkrete Umweltsituation und die individuellen Situationsmerkmale berücksichtigen muss, ist - wie diese Arbeit zeigt - eine simple Übertragung strategischer Allgemeinplätze aus Militär und Ökonomie von vornherein zum Scheitern verurteilt.
Fire plays an important role in the earth system by influencing ecosystems and climate, but climate in turn also influences fire. The system became more complex when humans started using fire as a tool. Understanding the interaction between humans, fire and climate is the major aim of paleofire research. Understanding changes in these three aspects in the past will help predicting future climate, fire and human interactions. The use of lake sediment cores as natural archives for reconstructing past fire activity by counting charcoal particles is well established. This present dissertation is dedicated to the evaluation and application of specific organic molecular markers for biomass burning: levoglucosan, mannosan and galactosan were used as proxies for reconstructing past fire activity in lake sediments thorough the entire Holocene. First, a new analytical method was developed using high-performance anion exchange chromatography combined with mass spectrometry to separate and detect these three monosaccharide anhydrides in lake sediments. The suitability of this analytical method was proven by comparing the levoglucosan, mannosan and galactosan results in selected lake sediment samples from Lake Kirkpatrick, New Zealand and by correlating the results with macroscopic charcoal. Furthermore, the method was successfully applied to a lake sediment core from Lake Petén Itzá, Guatemala to reconstruct regional Holocene fire history. The analyses of levoglucosan were combined with fecal sterols to reconstruct late Holocene human fire interactions at Lake Trasimeno, Italy, demonstrating low fire activity during the Roman period. This combination of studies proves that these molecular markers are valid fire proxies in sediments from multiple locations around the globe. Comparison of levoglucosan, mannosan and galactosan concentrations with macroscopic charcoal trends in Lake Kirkpatrick and Lake Petén Itzá, suggests that the molecular markers represent more regional fire history and low temperature fires in contrast to macroscopic charcoal, which is a local fire proxy. In addition, vegetation changes (Lake Kirkpatrick and Lake Petén Itzá) and charcoal morphotypes (Lake Petén Itzá) were compared to the levoglucosan/mannosan and levoglucosan/(mannosan+galactosan) ratios suggesting that these ratios may be a suitable tool to track burned fuel. Biodegradation tests demonstrate the potential degradation of levoglucosan, mannosan and galactosan if dissolved in water, but findings in ancient sediment samples suggest that particle-bound levoglucosan, mannosan and galactosan can be buried in sediments over millennial time scales. Although uncertainties still exist, the results of this research suggests that organic molecular markers are a suitable regional fire proxy and isomer ratios may help understand changes in burned vegetation.
The worldwide decline of plant and insect species during the last decades has far-reaching consequences for the functionality of ecosystems and their inherent processes. Pollination as one of them is an indispensable ecosystem service for human wellbeing. However, an increasing number of pollinator and plant species are threatened by multiple, interacting, and sometimes synergistic causes that are becoming a growing threat to ecosystem functioning. Given the loss of plant species diversity, it is increasingly difficult for pollinators to find food throughout the year. Therefore, this study analyses the influence of plant diversity on pollinators. The study was conducted in the course of the Jena Experiment, which is a long-term biodiversity experiment (since 2002) with 60 plant species, common to Central European Arrhenatherum grasslands. With a plant diversity gradient of 1, 2, 4, 8, 16, and 60 plant species per plot, time-series data resulted from a wide range of ecosystem processes, ranging from productivity, decomposition, C-storage, and N-storage to herbivory, and pollination. These were studied to investigate the mechanisms underlying the relationships between biodiversity and ecosystem processes. Chapter 2 studies the spatio-temporal distribution of pollinators on flowers along an experimental plant diversity gradient. In particular, the spatial pollinator behaviour was examined. Chapters 3 and 4 continues on the chemical composition of flower nectar (nectar) of various plant species. The chemical composition of the nectar was analysed for the two most important macronutrients, carbohydrates (C) and amino acids (AA), using high performance liquid chromatography (HPLC). Subsequently, their contents were analysed in terms of concentration, proportional content and the ratio of carbohydrates to amino acids (C:AA). In Chapter 3, the nectar of 34 plant species from the grasslands of the Jena Experiment was compared. In Chapter 4, nectar was investigated in the context of diversity effects on the example of the plant species Field Scabious, Knautia arvensis. It was analysed to what extent the nectar quality (nutrient content) differs between plant individuals of one species. Overall, these studies indicate how fragile plant-pollinator interactions are but also how important plant species-rich grasslands are to support plant-pollinator interactions. Increased plant species diversity is essential to ensure the availability of flowering resources throughout the year. Pollinators, such as honeybees, bumblebees, solitary bees, and hoverflies can use the niches in time and in vertical space complementarily. However, in plant species-poor grasslands there may be more niche overlaps, which is probably due to a reduced availability of resources. This points to the need to include different plant species belonging to different plant families, whose nectar may have evolved in response to morphological flower traits and metabolic pathways. Therefore plant species diversity can supply pollinators with nectar differing in carbohydrate and amino acid content and thus differing in quality. Also C-AA ratios have proven to be a useful measurement to reveal differences between plant species. In addition, C:AA ratios were not differing in nectar of K. arvensis individuals growing in different plant species richness levels, although their nectar seemed to be more attractive in mixtures with 16 plant species, likely due to higher content of essential and phagostimulatory amino acids than in plant species-poor mixtures.
"Sustainable development" evolves along the resolutions, declarations, and reports from international processes in the framework of the United Nations (UN). The consensual outputs from such processes feature global-generalised and context-free perspectives. However, implementation requires action at diverse and context-rich local levels as well. Moreover, while in such UN processes national states are the only contractual parties, it is increasingly recognised that other ("nonstate") actors are crucial to sustainability. The research presented here places the attention on bottom-up initiatives that are advancing innovative ways to tackle universal access to clean energy and to strengthen small-scale family farmers. This means, the focus is on bottom-up initiatives advancing local implementation of global sustainability targets, more precisely, targets that make part of the Sustainable Development Goals 2 and 7 (SDG 2 and SDG7). The research asks how such bottom-up initiatives can contribute to the diffusion of sustainability innovations, thereby also contributing to social change. Three aims are derived out of that central question: (1) To understand the role of bottom-up initiatives in the diffusion of sustainability innovations and in the thereby involved social changes. (2) To contribute with my research to the actual diffusion of sustainability innovations. (3) To outline a research approach that provides a solid conceptual and methodological framework for attaining the analytical and transformative aims. The doctoral research comprises four single studies, in which the notion of diffusion is explored at different scopes of social scales. It begins with a thorough analysis of diffusion programs of domestic biodigesters to rural households in countries of the global south. The focus is on the process by which this specific technical inno0vation results integrated (or not) into the daily realities of single rural households, that is, the adoption process. In the second study, the attention is on energy supply models based on different decentralised renewable technologies. Central to these models is the building of new (or strengthening of existing) local socioeconomic structures that can assume and ensure the proper operation and supply of energy services. The interest in this study is on the strategies that organisations implementing community-based energy projects apply to support the realisation of such local structures. The third study focuses on a network of bottom-up initiatives that have been advancing alternative approaches to family farming in Colombia. The network mainly comprises farmers associations, other organisations from civil society, and researchers who had been collaborating and experimenting with innovations in different innovation fields such as technical, organisational, financial, and commercialisation schemes. The aim of this third study is to provide insights into the challenges and difficulties faced by these actors in broadening the diffusion of the innovations they have been advancing. To perform this study, a methodological strategy is applied that combines a transdisciplinary mutual learning format with qualitative content analysis techniques. The fourth and last study is a conceptual disquisition. It develops a conceptual framework that (a) provides better accounts for the particularities of endeavours aimed at the diffusion of knowledge and practices from the bottom-up across local contexts and social scales, and (b) advances first conceptual steps towards an explicit account for the role that innovation research (and innovation researchers) can assume for the actual realisation of diffusion. The main findings or contributions of the doctoral research can be categorised into four subjects: 1) Bottom-up initiatives contribute to the diffusion of sustainable innovations by mobilising transformative resources for inducing diffusion in their scope of action and creating spaces for experimentation in which interventions can be tested (and if necessary adjusted) in order to ensure the proper deployment of innovations. 2) In their efforts to advance the diffusion of sustainability innovations, bottom-up initiatives contribute to social changes for ensuring the effective deployment of the innovations and building local available storage of transformative resources. 3) A conceptualisation of innovation diffusion, in which the work of academic researchers studying innovation is a constitutive part of transdisciplinary knowledge articulations that promote diffusion. In this way transdisciplinary research alliances can be envisioned in which researchers investigate about, with, and for bottom-up initiatives. 4) Contributions to the consolidation, systematisation, and dissemination of strategies that are applied by farmers associations in order to strength the economic, social, environmental, and cultural dimensions of Colombian family farmers.
Undertaking local actions, such as implementing public (sustainability) policy, plays a crucial role in achieving sustainable development (SD) at the municipal level. In this regard, indicator-based assessment supports effective implementation by measuring the SD process, based upon evidence-based outcomes that indicators produce. Over the last decade, using subjective indicators, which rely on an individual's self-perception to measure subjects, has gained its significance in sustainability assessment, in line with the increasing importance of signifying individual's and community's well-being (WB) in the context of SD. This study aims to discuss and clarify the scope and functions of subjective sustainable development indicators (SDIs) conceptually and theoretically while examining the usability of such indicators employed in the practice of assessing sustainability policy and action process in a Japanese municipality. Furthermore, the potential usability of using subjective SDIs in monitoring a municipal initiative of the United Nations’ Sustainable Development Goals (SDGs) is also explanatorily examined. The present paper consists of a framework paper and three individual studies. In the framework paper, Section 1 introduces the global transition of SD discourse and the role that local authorities and implementing public policy play in achieving SD while outlining how WB positions in the SD context. Section 2 provides a brief overview of the major scope of overall SDIs at the conceptual and theoretical levels. Section 3 defines WB in the study's own right while exploring the scope of indicators measuring WB. In addition, this study strives to further clarify the peculiar scope of SDIs, measuring WB by synthesising the findings. Section 4 overviews how SD at the municipal level in Japan is practiced while acknowledging the extent to which residents perceive WB and SDGs in policymaking. Section 5 provides a brief yet extensive summary of the three individual studies. Section 6 discusses the findings while presenting implications for further study and practices of subjective SDIs. Furthermore, the three individual studies provide a thorough and in-depth discussion of the study subject. Study 1 illustrates the SD trend at the municipal level in Japan and the growing recognition of using subjective SDIs in public (sustainability) policy assessment in exploring comparative SDI systems to municipality groups. The findings, in turn, raise the need for a further study on subjective SDIs. Study 2 extensively discusses the concept of WB as the overarching subject to be measured while examining varying approaches and scopes of SDIs. It identifies three differentiated WB (i.e., material and social objective WB as well as subjective WB) and distinctive approaches of subjective SDIs (i.e., expert-led and citizen-based approaches) alongside objective SDIs. The findings suggest that these SDIs identified are, conceptually, most capable of measuring associated WB; for instance, citizen-based subjective SDIs can most optimally measure subjective WB. Finally, Study 3 examines the usability of (citizen-based) subjective SDIs in a practice of assessing public policy, aiming at municipal SD, and the potential usability of using such indicators in monitoring a municipal SDG initiative. The findings highlight the determinants and obstacles of using subjective SDIs as well as signifying WB in measuring progress of a municipal SD practice.
Among all attenuation processes, biodegradation plays one of the most important role and is one of the most desirable processes in the environment. To assess biodegradation, a variety of biodegradation test procedures have been developed by several international organizations. OECD guidelines for ready biodegradability testing represent one of the most prominent group of internationally used screening biodegradation tests (series 301A-F). These tests are usually very simple in their designs and allow for the fast and cheap screening of biodegradability. However, because of their stringency, the test conditions are not close to simulating environmental conditions and may lead to unrealistic results. To overcome these limitations, OECD introduced simulation tests which are designed to investigate the behavior of chemicals in specified environmentally relevant compartments. Despite the fact that simulation tests give more insight into the fate of chemicals in the environment, they are not applied frequently as they are often tedious, time consuming and expensive. Consequently, there is a need to provide a new biodegradation testing method that would combine complex testing environment as in simulation tests, easiness in handling and good data repeatability as in screening biodegradation tests. Another challenge is an adaption of the existing biodegradation testing methods to new types of samples, i.e. mixtures of transformation products (TPs). The research on the presence of pharmaceuticals in the environment gained momentum in the 1990s; since then, it has been growing. Their presence in the environment is a wellestablished fact. A wide range of pharmaceuticals is continuously detected in many environmental compartments such as surface waters, soils, sediments, or ground waters. After pharmaceuticals reach the natural aquatic environment they may undergo a number of processes such as: photolysis (under direct sunlight), hydrolysis, oxidation and reduction reactions, sorption, biodegradation (by bacteria of fungi), and bioaccumulation. These processes, may cause their elimination from aquatic environment, if reaction is complete, or creation of new compounds i.e., transformation products (TPs). What is more, processes, like chlorination and advanced oxidation processes (AOPs), such as H2O2/UV, O3/UV, TiO2/UV, Fenton, and photo-Fenton, or UV treatment which might be applied in water or wastewater treatment, may also lead to the TPs introduction into aquatic environment. The research on the TPs brings many new challenges. From one side, there is a constant need for the the development of a sensitive and reliable analytical separation, detection, and structure elucidation methods. Additionally, there is a need for the preparation of appropriate assays for the investigation of properties of new compounds, especially those answering the question if TPs pose a higher risk to the aquatic ecosystems than their parent compounds. Among numerous groups of pharmaceuticals, two are of great importance: antibiotics since they might promote emergence and maintenance of antimicrobial resistance in the aquatic environment; and cytostatic drugs. Cytostatic drugs can exert carcinogenic, mutagenic and/or teratogenic effects in animals and humans. The challenges of biodegradation testing presented in this thesis, encompasses these different areas of interest and was divided into three objectives: 1) Identification of the knowledge gaps and data distribution of the two groups of pharmaceuticals antibiotics and cytostatic drugs (article I); 2) Increasing the knowledge on biodegradation of cytostatic drugs and their TPs (articles II, III, and IV) and 3) Establishment of a biodegradation test with closer to simulation tests conditions, that could be affordable and to support better understanding on processes in water sediment interface construction - screening water-sediment test. Further validation of the test with an insight into sorption and desorption processes (articles V and VI).
Global climate change and environmental degradation are largely caused by human activity, thus progress towards a sustainable future will require large-scale changes to human behavior. Human-nature connectedness (HNC) - a measure of cognitive, emotional, spiritual and biophysical linkages to natural places - has been identified as a positive predictor of sustainability attitudes and behaviors. While calls to "reconnect to nature" in order to foster sustainability outcomes have become common across science, policy and practice, there remains a great deal of uncertainty, speculation, and conceptual vagueness around how this ought to be implemented. The overarching aim of this thesis is to advance conceptual and empirical understandings of HNC as a leverage point for pro-environmental outcomes and sustainability transformation. In particular, the thesis attempts to assess the nuances of the HNC-PEB (pro-environmental behavior) relationship by investigating the scalar relationships between where someone feels connected to nature and where someone acts pro-environmentally. This research was conducted through conceptual exploration, systematic literature reviews using hierarchical cluster analysis, and empirical case studies relying on structural equation modeling and two-step cluster analysis. The relationship between HNC and pro-environmental attitudes and behaviors was investigated in a small microregion of Transylvania, Romania, where traditional relationships with the land and changing socio-economic characteristics provided an interesting case study in which to explore these connections. The key findings can be organized into three sections: Section A, which addresses HNC and its potential for sustainability transformation; Section B, which addresses HNC as a determinant of PEB outcomes, and Section C, which explores the relationships between human-nature connectedness and energy conservation norms, attitudes, and behaviors. Results cumulatively suggest that HNC is a multidimensional construct that requires greater integration across heterogeneous disciplinary and methodological boundaries in order to reach its potential for meaningful sustainability transformation. Results also highlight the critical need to adopt systemic approaches to understanding how interactions between human-nature connections, norms, attitudes, and behaviors are hindering or promoting sustainability outcomes.
This dissertation deals with the increasingly recognized role of incumbent firms in advancing sustainability-oriented industry transitions. Incumbent firms are understood as firms-in-industries, which are embedded in established market structures and thereby contrast new entrant firms. The purpose of this research is twofold. First, to provide empirical evidence of barriers to and success factors of incumbent-driven industry transitions. Second, to unify hitherto dispersed descriptions of transition-related firm behaviour in a new understanding of incumbent firms in industry transitions. To this end, theoretical concepts are discussed and extended on the basis of different empirical studies in the German meat industry. The meat industry serves as suitable research setting due to its diverse sustainability challenges, ranging from climate change and pollution to animal welfare and public health, as well as its current developments towards sustainable protein alternatives. The meat context also offers opportunities to delve into individual-level processes influencing transition-related behaviour. The main contribution of this dissertation is a Multi Embeddedness Framework (MEF) that details processes and outcomes of integrated incumbent firm behaviour, including passive, reactive and proactive behaviors. The framework acknowledges the diversity in incumbent firm behaviors within industries and firms and provides new insights into transition-related behaviors at firm and individual level. With regard to the latter, the potential of learning about and from innovative start-up firms as well as shared sensemaking processes are discussed. The contents of this dissertation provide valuable contributions to the transition literature as well as important management implications with regard to the stimulation and promotion of proactive behaviors
Restoration and management of abandoned, dry Continental heathland and sandy grassland communities
(2018)
Whereas heathlands in the Atlantic biogeographical region have been in the centre of interest, dry heathland communities in the Continental biogeographical region have been widely neglected. Thereby, the conservation status of both habitat types is listed as unfavourable-bad across the Continental biogeographical region. Surprisingly, no detailed studies are available on cost-efficient and sustainable restoration and management schemes to successfully restore and maintain highly degraded, long-abandoned Continental heaths and sandy grasslands, and thus, to counteract the poor conservation status of the habitat types. This shows the great need for research for the Continental biogeographical region. Thus, the present thesis provides substantial knowledge about the population dynamics of the key plant species of dry heaths Calluna vulgaris (L.) HULL by investigating key processes in the biology of the species as well as about the restoration and management of long-abandoned, dry Continental heathland and sandy grassland communities. In order to better understand the process of successful Continental heathland restoration, I analysed the reproductive potential (seed production, soil seed bank, and germination ability of seeds) of degenerate Calluna stands as well as the effects of single and combined management options on the generative rejuvenation (i.e., recruitment and survival) of Calluna. The results are based on a comprehensive three-year field experiment including the management options year-round, low-intensity cattle and horse grazing, one-time mowing and one-time shallow soil disturbances combined with greenhouse investigations on the soil seed bank content and germination ability of Calluna seeds. The results showed that even after long-term abandonment, seed production of degenerate Calluna stands and the germination ability of seeds proved to be high, being similar to Atlantic heathlands, whereas the soil seed bank is considerably reduced probably due to the dry conditions in the Continental region. In addition, low-intensity grazing with free-ranging robust breeds and the combination with one-time mowing at the beginning of the restoration process is an effective means of supporting the generative rejuvenation of this key plant species in degraded Continental heaths. The second study of this thesis focussed on the first-year establishment of Calluna in managed and unmanaged dry heaths and heaths in mosaics with dry sandy grasslands. The germination ability of seeds of different life-history phases of Calluna was analysed to determine if the predominance of the late life-history phase restricts the rejuvenation process of this key plant species. In addition, beside effects of management measures (year-round, low-intensity grazing, one-time mowing, one-time shallow soil disturbances) the author analysed the most important safe site conditions that possibly influenced the germination and the first-year survival of Calluna. The results of the study combine field experiments with growth chamber investigations. The author found that life-history phase of Calluna did not significantly affect seed germination and thus, the predominance of the degenerate life-history phase does not restrict the rejuvenation process. In addition, the results of the study revealed that grazing and thus trampling intensity must be temporarily and locally enhanced at the beginning of the restoration process of highly degraded heaths to increase safe site availability for successful Calluna establishment. Thereby, shadowing is the most important safe site condition. In the third study, the author investigated the impacts of year-round low-intensity cattle and horse grazing on the development of the highly competitive grass Calamagrostis epigejos (henceforth referred to as Calamagrostis), as well as the vegetation structure and plant species richness of long-abandoned but nutrient-poor dry heathland and sandy grassland communities, their mosaics and Calamagrostis stands. Finally, I assessed the local conservation status of the habitat types after seven years of grazing in comparison to long-abandoned sites. The results are based on a comprehensive field study on two spatial scales (plot-level: 25 square meters, macroplot-level: 1 ha). The author found that grazing successfully reduced the coverage and prevented the further spread of Calamagrostis, while simultaneously maintained or improved characteristic species richness and vegetation structure across the different nutrient-poor vegetation types over time, and thus enhanced the local conservation status of habitat types of community interest. In conclusion, the results of the studies considerably improved the understanding of dry, Continental heathland and sandy grassland restoration and management. They provide evidence that even after long-term management abandonment, year-round low-intensity cattle and horse grazing is a suitable management tool for restoring, maintaining and even improving nutrient-poor heathland and sandy grassland communities. However, at the beginning of the restoration process, additional management measures are necessary to faster restore abandoned habitats, especially highly degraded heaths.
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.
The German energy system is under transformation. The so-called Energiewende (in English, Energy turn) relies, among other things, on renewable energies for building a more sustainable energy system. Regions (Landkreise) are one relevant level where different administrative bodies make decisions and plans both for the implementation and for the use of renewable energies. However, in order to realize the goals of the Energiewende, developments in the wider society are necessary. This is why scientific research can and should foster such developments with more research on the social aspects of energy-related topics. The present work contributes to the understanding of transition processes towards a sustainable use of regional renewable energy by focusing on the role of contextual conditions, practical experiences, and temporal dynamics in the implementation and use of renewable energy in German regions. In this way, this work wants to contribute fostering the development of regional energy transition strategies for the realization of the Energiewende. The conceptual background for this piece of transformation research lies in three bodies of literature dealing respectively with transitions of socio-technical systems, transformations of socioecological systems, and time ecology. From a critical engagement with this literature, three main results have emerged. First, an evidence-based, spatially distinct analysis of contextual conditions for the use of renewable energy in all German regions has resulted in the identification of nine types of regions, so-called energy context types. Second, empirical research on practices in regional settings learned from the knowhow of actors from regional administration has shown that political and economic conditions are crucial as well as that process management, exchange, and learning are helpful for renewable energy implementation. Third, conceptual work about a deeper understanding of the temporal dimensions of transformation processes has made it possible to point out a three-step approach to include temporal dynamics into sustainability transformations management - the time-in-transformations-approach. The literature suggests that regions need to be treated individually; but developing an energy transition strategy for each region individually would be extremely resource intensive. Overall, this work outlines a compromise for a more efficient approach towards regional energy transition strategies which still considers the individuality of regions. As a result, the author suggests to develop generic regional energy transition strategies that are adapted to each of the nine energy context types of German regions, that include the experiences of practitioners, and that consider temporal dynamics of transformation processes. Transdisciplinary research is a promising approach to meet many of the challenges for the realization of the Energiewende.
Tropical forests worldwide support high biodiversity and contribute to the sustenance of local people’s livelihoods. However, the conservation and sustainability of these forests are threatened by land-use changes and a rapidly increasing human population. This dissertation, therefore, aimed to characterize biodiversity patterns in the moist Afromontane forests of southwestern Ethiopia and to examine how biodiversity patterns are affected by land-use and land-use changes (mediated by coffee management intensity, landscape attributes and housing development) in a context of a rapidly growing rural population. To achieve this goal, the author takes an interdisciplinary approach where, first, she examined the effects of coffee management intensity on diversity patterns of woody plants and birds, spanning a gradient of site-level disturbance from nearly undisturbed forest interior to highly managed shade coffee forests. Results showed that specialized species of woody plants (forest specialists) and birds (forest specialists, insectivores and frugivores) were affected by coffee management intensity. The richness of forest specialist trees and the richness and/or abundance of insectivores, frugivores and forest specialist birds decrease with increasing levels of disturbance. Second, the author investigated the effects of landscape context on woody plants, birds and mammals. Community composition and specialist species of woody plants and birds were sensitive to landscape context, where woody plants responded positively to gradients of edge-interior and birds to gradients of edge-interior and forest cover. Further results showed that a diverse mammal community, with 26 species, occurs at the forest edge of shade coffee forests and that the leopard, an apex predator in the region depended on large areas of natural forest. A closer examination of leopard activity patterns revealed a shift in the diel activity as a response to human disturbance inside the forest, further highlighting the importance of natural undisturbed forests for leopards in the region. Together, these findings demonstrate the value of low managed shade coffee forests for biodiversity, and importantly, emphasize the irreplaceable value of undisturbed natural forests for biodiversity. Third, the researcher investigated the effects of prospective rural population growth (mediated by housing development) on the forest mammal community. Here, population growth was projected to negatively influence several mammal species, including the leopard. Housing development that encroached the forest entailed worse outcomes for biodiversity than a combination of prioritized development in already developed areas and coffee forest protection. Fourth, to understand the motivations behind high human fertility rates in the region, she examined the determinants of women fertility preferences, including their perceptions on social and biophysical stressors affecting local livelihoods such as food insecurity and environmental degradation. Fertility preferences were influenced by underlying social norms and mindsets, a perceived utilitarian value of children and male dominance within the household, and were only marginally affected by perceptions of social and biophysical stressors. The findings suggest the need for new deliberative and culturally sensitive approaches that engage with pervasive social norms to slow down population growth. Overall, this dissertation demonstrates the key value of moist Afromontane forests in southwestern Ethiopia for biodiversity conservation. It indicates the need to promote coffee management practices that reduce forest degradation and highlights that high priority should be given to the conservation of undisturbed natural forests. It also suggests the need to integrate conservation goals with housing development in landscape planning. A promising approach to achieve the above conservation priorities would be the creation of a Biosphere Reserve and to promote the ecological connectivity between the larger forest remnants in the region. Finally, this dissertation demonstrates the importance of placed-based holistic approaches in conservation that consider both proximate and distal drivers of forest biodiversity decline.
Im Projekt "Nawi-In" (Naturwissenschaftlichen Unterricht inklusiv gestalten) wurde die Entwicklung professioneller Kompetenzen für den inklusiven naturwissenschaftlichen Unterricht von Lehramtsstudierenden der Primar- und Sekundarstufe beforscht. Dabei wurden Lehramtsstudierende des naturwissenschaftlichen Primar- und Sekundarstufenunterrichts über drei Semester im Projektbandseminar begleitet. Als Teilprojekt des Projekts "Nawi-In" setzt diese Arbeit den Schwerpunkt auf drei Fokusse: die Entwicklung des Kategoriensystems inklusiver naturwissenschaftlicher Unterricht (KinU), die Beforschung der professionellen Handlungskompetenz sowie der professionellen Wahrnehmung bezüglich inklusiven naturwissenschaftlichen Unterrichts. Im ersten Fokus geht es sowohl um die Entwicklung und Validierung des KinUs als auch um die Überprüfung der Gütekriterien des KinUs. Zunächst wurden die Charakteristika inklusiven naturwissenschaftlichen Unterrichts, die die Kategorien des KinUs 1.0 darstellen, in einem systematischen Review aus der Literatur induktiv abgeleitet. Die Kategorien (n=935) verteilten sich auf insgesamt vier Abstraktionsebenen von der allgemeinen Hauptkategorienebene über die Subkategorien-, Code- bis hin zur konkreten Subcode-Ebene des KinUs. Während zunächst n=16 Kategorien die Verbindung naturwissenschaftlicher Charakteristika mit der inklusiven Umsetzung auf der Hauptkategorien-Ebene gebildet haben, waren es nach der Weiterentwicklung und Überarbeitung des KinUs 2.0 n=15 Hauptkategorien. Die Weiterentwicklung des KinUs fand mithilfe der Validierung durch Datentriangulation statt. Durch die Anwendung des KinUs auf Video- und transkribierte Audiodaten wurden fortlaufend weitere Kategorien induktiv abgeleitet. Zudem wurde die Struktur des KinUs vereinfacht, sodass die inklusiven Zugänge zu jedem naturwissenschaftlichen Charakteristikum bis zur Code-Ebene als ein gleichbleibendes Muster abgebildet werden können. Der zweite Fokus bezieht sich auf die Entwicklung und Beforschung der professionellen Handlungskompetenz der Lehramtsstudierenden bezüglich inklusiven naturwissenschaftlichen Unterrichts. Dabei wurde analysiert, welche inklusiv naturwissenschaftlichen Charakteristika Lehramtsstudierende in ihrem Unterricht implementieren, wie sich ihre professionelle Handlungskompetenz während der Praxisphase entwickelt sowie welche Unterschiede und Gemeinsamkeiten sich für die Primar- und Sekundarstufen bezüglich ihrer professionellen Handlungskompetenz ergeben. Dafür wurden die Unterrichtsvideos, die die Studierenden während der Praxisphase jeweils zweimal von ihrem eigenen Unterricht angefertigt haben, mit dem KinU qualitativ inhaltlich analysiert. Insgesamt haben die Studierenden zwar unterschiedliche Zugänge auf der Subkategorien-Ebene zum naturwissenschaftlichen Unterricht implementiert, allerdings haben sie den Schülern innerhalb dieser Zugänge nur selten verschiedene Optionen geboten. Im Vergleich der Schulstufen zeigt sich, dass sich die zunehmende Fachlichkeit von der Primar- zur Sekundarstufe widerspiegelt. Insgesamt haben die Studierenden von dem ersten zum zweiten Unterrichtsvideo zunehmend mehr inklusiv naturwissenschaftliche Charakteristika in ihren Unterricht implementiert. Im dritten Fokus wurde die professionelle Wahrnehmung von Lehramtsstudierenden bezüglich inklusiven naturwissenschaftlichen Unterrichts beforscht. Dabei wurde analysiert, welche inklusiv naturwissenschaftlichen Charakteristika Lehramtsstudierende wahrnehmen, wie sich ihre professionelle Wahrnehmung entwickelt sowie welche Unterschiede und Gemeinsamkeiten sich für die Primar- und Sekundarstufe bzgl. ihrer professionellen Wahrnehmung ergeben. Dafür wurden video-stimulierte Reflexionen durchgeführt, wobei die Studierenden Videoszenen bzgl. inklusiven naturwissenschaftlichen Unterrichts beschreiben, interpretieren sowie Handlungsalternativen generieren sollten. Bei den Video-Stimulated Reflections (VSRef) haben die Studierenden eine Videovignette aus einem Sachunterricht zum Thema Löslichkeit reflektiert. Die VSRefs wurden zu drei Zeitpunkten durchgeführt: vor dem ersten Mastersemester und vor sowie nach der Praxisphase im zweiten Mastersemester. Zudem wurden während der Praxisphase jeweils zweimal mit allen Studierenden Video-Stimulated Recalls (VSR) durchgeführt. Dabei haben die Studierenden Ausschnitte ihrer eigenen Unterrichtsvideos reflektiert. Sowohl die VSRef als auch die VSR wurden transkribiert und mit dem KinU qualitativ inhaltlich analysiert. Die Lehramtsstudierenden haben zunehmend mehr inklusiv naturwissenschaftliche Charakteristika in den eigenen und fremden Unterrichtsvideos wahrgenommen. Zwischen den Schulstufen waren nur geringe Unterschiede zu erkennen. Am häufigsten haben die Studierenden Zugänge zur inklusiven Gestaltung der Anwendung naturwissenschaftlicher Untersuchungsmethoden wahrgenommen. Insgesamt zeigt sich, dass die Lehramtsstudierenden ihre professionellen Kompetenzen bzgl. inklusiven naturwissenschaftlichen Unterrichts weiterentwickeln konnten. Zudem wurde mit der Entwicklung des KinUs ein Kategoriensystem zur Beforschung und ein Unterstützungsraster für Lehrkräfte zur Gestaltung inklusiven naturwissenschaftlichen Unterrichts geschaffen.
Collaborative governance is a promising approach to address the difficult challenges of sustainability through global public and private partnerships between diverse actors of state, market and civil society. The textile and clothing industry is an excellent example where a variety of such initiatives have evolved to address the wicked sustainability challenges. However, the question arises whether collaborative governance actually leads to transformation. In this dissertation, the author therefore questions whether and how collaborative governance in the textile sector provides space for, or pathways to, sustainability transformation. In three scientific articles and this framework paper, the author uses a mixed-methods research approach and follows scholars of sustainability science towards transformation research. First, he conducts a systematic literature review on inter-organizational and governance partnerships before diving into a critical case study on an interactive collaborative governance initiative, the German Partnership for Sustainable Textiles (Textiles Partnership). The multi-stakeholder initiative (MSIs) was initiated by the German government in 2015 and brings together more than 130 organizations and companies from seven stakeholder groups. It aims at improving working conditions and reducing environmental impacts in global textile and clothing supply chains. In two empirical articles, the author then explores learning spaces in the partnership and the ways in which governance actors navigate the complex governance landscape. For the former, he uses a quantitative and qualitative social network analysis based on annual reports and qualitative interviews with diverse actors from the partnership. Then, he uses qualitative content analysis of the interviews, policy documents and conducts a focus group discussion to validate assumptions about the broader empirical governance landscape and the social interactions within. Finally, in this framework paper, he uses theories of transformation to distinguish forms of change and personal, political and practical spheres of transformation, and reflects on the findings of the three articles in this cumulative dissertation.
Social insects like honeybees (Apis mellifera) and stingless bees (Apidae: Meliponini) face a relatively high risk to be attacked by pests and pathogens. To decrease the risk of infection, in addition to an innate immune system, these species have evolved various cooperative defense mechanisms which contribute to the overall health of the colonies and are therefore also referred to as social immunity. The collection and use of plant resin is another important strategy of social immunity. Resin is a sticky, often aromatic substance with antimicrobial and deterrent properties secreted by plants for protection of the vegetative tissue. Honeybees and stingless bees take advantage of these properties by using resins for nest construction (often mixtures of resin and wax called "propolis" or "cerumen") and as defense against pests and pathogens. Plant resins, thus, play a crucial role for the ecology of these species and are an important resource for them. Nevertheless, how bees exploit available resin sources and if resin collection can protect colonies from diseases received comparatively little attention in the past. Therefore the aim of this thesis is to provide new insights into the plant origin and significance as well as the influence of resin resource diversity on bee colony health. For honeybees (A. mellifera) in temperate regions, precise information about which resin sources they use is largely lacking. By chemical comparing bee-collected resins and tree resins, the researcher traced back the resin sources used by individual bees. Results show that honeybees collect distinct resin types that are related to different tree species (several poplar species: Populus balsamifera, P. xcanadensis; Betula alba; Aesculus hippocastanum; several poplar species). With this study, the author provided the first evidence, that A. mellifera in temperate regions use a variety of different tree species as resin sources and, moreover, show preferences for specific resin sources. Furthermore, the researcher conducted an experimental field study in which she investigated whether propolis, as it is naturally deposited in the nests, can protect honeybee colonies against some of the most important pathogens (Varroa destructor mite, Deformed Wing Virus). The results of this study showed that propolis in (semi-) natural conditions can increase the disease resistance of honeybee colonies, underscoring the importance of resins for honeybee health. Resin collection by stingless bees is comparatively well studied and it is known that these species commonly forage on a variety of different plant species. To increase knowledge on whether and how bees may profit from a diversity of resin resources, the researcheer tested how the protective function of a resin varied among different sources (and their mixtures) and various potential aggressors (predators, parasites and pathogens). The results of this study revealed that resins from different trees vary in their effectivity against different target organisms. Moreover, resin blends were more effective than some of the individual resins, suggesting that bees can benefit from a variety of resin resources. In summary, honeybees in temperate regions, similar to tropical stingless bees, use a variety of different tree species as resin sources. Because resins from different tree species varied in their protective function, this indicates that bees can profit from a variety of different resins/resin sources by improving the defense against diverse pests and pathogens. Conversely, the lack of resin had a negative impact on the disease resistance of colonies. Consequently, availability as well as the variety of suitable resin sources is of great importance for the health of bees.
Zur Ermittlung der Belastung der Elbe mit Pestiziden wurden chemische Analyseverfahren entwickelt, wobei das untersuchte Stoffspektrum insgesamt 106 Analyte umfasste. Die Untersuchungen ermöglichten 1989 eine erstmalige Identifizierung und Quantifizierung von Pestiziden in hohen Konzentrationen (unterer µg/L-Bereich) im Elbeästuar, nach der Wiedervereinigung deren Rückverfolgung zu industriellen Punktquellen in der ehemaligen DDR (Längsprofile), eine Erfassung der historischen Entwicklung der Belastungssituation in den 90er Jahren, die Feststellung der zunehmenden Bedeutung von Einträgen aus diffusen Quellen im Vergleich zu Punktquellen sowie die Ermittlung des Stoffspektrums und der zeitlichen und örtlichen Variabilität innerhalb eines Zeitraumes von drei Jahren (Monatsmischproben und Zeitreihen an unterschiedlichen Querschnitten der Elbe sowie Längsprofile). Der Fokus richtete sich im weiteren Verlauf auf die Entwicklung chemischer Analyseverfahren zur sicheren Identifizierung und Quantifizierung von Wirkstoffen mit niedrigen Qualitätszielen/-kriterien (unterer ng/L- bzw. sub-ng/L-Bereich). Zur Bewertung der Belastungssituation und zur Diskussion von Monitoring-Strategien wurden national und international verfügbare Qualitätsziele/-kriterien insbesondere für die aquatische Lebensgemeinschaft herangezogen.
Organophosphorus flame retardants and plasticizers (OPEs) have been utilized for decades as plasticizers and, to a lesser extent, as flame retardants in various consumer products to improve their material properties. The research presented in this thesis investigated the occurrence, distribution and transport of OPEs with a focus on the coastal and estuarine environment. Due to the wide range of physicochemical properties of OPEs, the environmental fate and behaviour of OPEs was investigated over a range of compartments, starting from the atmospheric occurrence to the aquatic phase and the behaviour in sediments. The aim was to gather information on the OPE contamination situation in the coastal and estuarine environments, to identify specific contamination patterns for source assessment and to investigate the distribution behaviour of OPEs between gas- and particle-phases to evaluate their environmental transport mechanism. To achieve these scientific goals, sensitive and robust chemical analytical methods for the detection and quantification of OPEs in a variety of environmental samples using gas-chromatography coupled with tandem mass spectrometry were developed. Water samples were removed along the Elbe and Rhine Rivers to test the hypothesis of whether specific point sources, such as wastewater treatment plants, are the major input pathways for OPE contamination in rivers. A total of 65 water samples, including an intensive measurement campaign during the flood event in 2013 at the Elbe, was taken and analysed for OPEs. No obvious point sources were identified along either of the rivers analysed. No significant increase or decrease in the OPE concentrations or a change in patterns were observed over a transect of over 300 km at the Elbe, with an increase in water discharge of 2.5. This finding suggested that the OPE input in large rivers is primarily driven by diffuse sources, such as surface runoff, or by minor point sources rather than local point sources. To examine the specific pattern of OPE contamination in individual rivers and estuaries, 37 sediment samples from 8 rivers in Europe and China were analysed. With this analytical data, a fingerprint analysis of the OPE patterns identified could be conducted. All the rivers investigated in Europe displayed a very similar fingerprint. In contrast, the fingerprint from China differed significantly from the one in Europe. For example, in China, the OPE restricted in Europe, Tris(2-chloroethly)phosphate, was found to be one of the major OPE components, while Tris(2-butoxyethyl) phosphate, a major compound in Europe, was negligible in China. The investigation showed that the fingerprinting analysis is a useful tool to identify different regions or characterize specific rivers regarding their OPE contamination. In addition, it could be shown that legislative restriction and processes have an impact on local or even EU-wide contamination patterns. At a coastal site next to the German city of Büsum, 58 air samples were taken over one year. Using the newly developed analytical method, it was possible to analyse the gas, as well as the particle phase, of the samples collected with very low detection limits for OPEs. In contrast to expectations, no annual trend in OPE concentrations, phase distributions or patterns was observed, but the investigation of the phase distribution challenged the previous scientific consensus that OPEs occur as primarily bound to particles in the atmosphere. Several compounds were detected in significant amounts in the gas phase. To validate these novel results, a model analysis based on the chemical properties of OPEs was conducted using three different phase distribution models. The results from the environmental data were strongly supported by the simulations, and the formal knowledge could be refuted. Consequently, the atmospheric transport assumptions and estimations about the long-range transport of OPEs have to be reassessed because compounds in the gas phase undergo other types of transport degradation and elimination mechanisms than particle-boundones. The novel findings presented in this thesis challenged an important aspect regarding the perceived scientific knowledge about the behaviour of OPEs in the environment and call on the scientific community to reassess the environmental behaviour of OPEs. The insights presented on the patterns highlight the impact of environmental policies and regulatory mechanisms to work towards the final goal of a good environmental status and the avoidance of adverse effects of discarded chemicals on humans and the environment.