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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.
Traditional farming landscapes typically support exceptional biodiversity. They evolved as tightly coupled social-ecological systems, in which traditional human land-use shaped highly heterogeneous landscapes. However, these landscapes are under severe threats of land-use change which potentially pose direct threats to biodiversity, in particular through land-use intensification and land abandonment. Navigating biodiversity conservation in such changing landscapes requires a thorough understanding of the drivers that maintain the social-ecological system. This dissertation aimed to identify system properties that facilitate biodiversity conservation in traditional farming landscape, focusing specifically on birds and large carnivores in the rapidly changing traditional farmland region of Southern Transylvania, Romania. In order to identify these properties, I first examined the effects of local and landscape scale land-use patterns on birds and large carnivores and how they may be affected by future land-use change (Chapters II-V). Second, to gauge the role of particular traditional land-use elements for biodiversity I focused on the conservation value of traditional wood pastures (Chapters VI-VIII). Third, I took a social-ecological systems approach to understand how links between the social and ecological parts of the system affect human-bear coexistence (Chapters IV and IX). Bird diversity was supported by the broad gradients of woody vegetation cover and compositional heterogeneity. Land-use intensification, and hence the loss of woody vegetation cover and homogenization of land covers, would thus negatively affect biodiversity. This was especially evident from predictions on the distribution of the corncrake (Crex crex) in response to potential future land cover homogenization. Here, a moderate reduction of land cover diversity could drastically reduce the extent of corncrake habitat. Further results showed that the brown bear (Ursus arctos) would mainly be affected by land-use change through the fragmentation of large forest blocks, especially if land-use change would reduce habitat connectivity to the presumed source population in the Carpathian Mountains. Moreover, this dissertation revealed that large carnivores (brown bear and wolf, Canis lupus) may have important and often ignored roles in structuring the ecosystem of traditional farming landscapes by limiting herbivores. Wood pastures were found to have a high conservation value. The combination of low-intensity used grasslands with old scattered trees provided important supplementary habitat for different forest species such as woodpeckers and the brown bear. Worryingly, current management of wood pastures differed from traditional techniques in several aspects, which may threaten their persistence in the landscape. The majority of people had a positive perception on human-bear coexistence. The use of traditional sheep herding techniques combined with the tolerance of some shepherds to occasional livestock predation facilitated coexistence in a region where both carnivores and livestock are present. More generally, the genuine links between people and their environment were important drivers of people´s positive views on coexistence. However, perceived failures of top-down managing institutions could potentially erode these links and reduce people´s tolerance towards bears. Through the consideration of two different animal taxa, this dissertation revealed six important system properties facilitating biodiversity conservation in traditional farming landscapes. Similar proportions of the main land-use types (arable land, grassland, and forests) support species richness at the regional scale possible through habitat connectivity and continuous spill-over between land-use types. Heterogeneous landscapes can further support biodiversity through complementation and supplementation of habitat at the landscape scale. Gradients of woody vegetation cover and heterogeneity, supported biodiversity at both local and landscape scales possibly through the provision of a wide range of resources. The heterogeneous character of the landscape is tightly linked to traditional land-use practices, which also maintain specific traditional land-use elements and facilitate human-carnivore coexistence. Top-down limitation of large carnivores on herbivores possibly enhances vegetation growth and tree regeneration. The genuine links between humans and nature support human-bear coexistence, and these links may form the core of people´s values and sustainable use of natural resources.
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.
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.
This dissertation deals with the investigation of success factors in the field of entrepreneurship, especially entrepreneurship training, from a psychological perspective. In particular, I argue that the identification of certain psychological aspects helps to better understand the underlying mechanisms for successful entrepreneurship trainings and thus, enables successful entrepreneurship. In the second chapter I theoretically examined planning as a fundamental action an entrepreneur hast to undertake in order to succeed. Scholars are in disagreement about the question if planning is crucial for the entrepreneurship. Thus, I provide a comprehensive overview of the advantages and disadvantages of planning in entrepreneurship from a psychological perspective. I explain negative aspects (e.g., lack of knowledge, difficulty to predict the future, and inflexibility) as well as positive aspects (e.g., legitimating, action-regulatory, and learning function) about planning in entrepreneurship. Furthermore, I develop a theoretical model that combines both the positive and negative aspects of planning in entrepreneurship. With this theoretical model, I integrate different types of planning (e.g., formal and informal plans) as well as positive and negative functions of planning (e.g., learning or stickiness, inflexibility) to provide a first approximation for a theory of entrepreneurial planning. In the third chapter, to focus on the field of entrepreneurial trainings, I empirically examine the under-researched field of the relation between trainer and trainee. I use the transformational leadership theory (Bass, 1985) and a theory of learning outcome (Kraiger, Ford, & Salas, 1993), to hypothesize that the trainers´ charisma has a positive effect on the trainees´ entrepreneurial self-efficacy. Additionally, I search for possible moderators for the hypothesized trainer-trainee-relationship in an explorative manner, using insight from different research areas (e.g., pedagogy, philosophy). To test the hypotheses, I conducted a 12-week entrepreneurship training by which I had 12 measurement waves across four classes with 161 students and 12 trainers, which lead to 919 observations. In the fourth chapter, to broaden the perspective on the mechanisms within entrepreneurship training, which lead to a successful outcome, I empirically examined the short- and long-term effects of entrepreneurship training on life satisfaction. To do so, I developed a theoretical model based on theories of life satisfaction, that explain the underlying mechanisms of the short- and long-term effects of the entrepreneurship training on life satisfaction. With this model I hypothesize, that entrepreneurship training has a positive short- effect on life satisfaction, which is mediated through entrepreneurial self-efficacy. I furthermore hypothesize, that the long-term effect of the entrepreneurship training is mediated through self-employment. The short term-effect acts like a boost and vanishes over time, whereas the long-term effect holds in the long run. To test these hypotheses, I conducted entrepreneurship training as part of a randomized controlled field experiment with five measurement waves over a total period of 2.5 years. Using discontinuous growth modeling to take into account the temporality of our hypothesized effects we statistically analyzed the 1,092 observations from 312 students. Chapter 5 concludes this dissertation with general discussion of the three chapters.
The future of forests is closely linked to climate change and energy transition because the preconditions for forest management are changed through climate and energy policies (Beland Lindahl and Westholm 2012). Forest management has multiple objectives, and different stakeholders have competing interests in forests. A strong dichotomy between environmental and economic interests has characterized forest policy and most conflicts about forests in the past (Winkel and Sotirow 2011). Climate change and energy transition modify this established conflict line because new conflicts related to climate mitigation, climate adaptation, and renewable energies have blurred the clear opposition between environmental and economic interest (Mautz 2010). In the context of the new challenges of climate change and energy transition, the need for effective, efficient and legitimate forest governance is gaining a new importance. Based on 86 qualitative interviews about forest conflicts and forest governance in five qualitative case studies, theoretical approaches focusing on multi-level and multi-scale governance are merged with the field of environmental and natural resource conflict research in this thesis. Forest conflicts and their governance are a multi-level and multi-scale issue. However, not so much is known about how collective and individual state and non-state actors act in complex governance systems and how they perceive governance systems. In order to contribute to the understanding of these knowledge gaps, this thesis tests the applicability of three theoretical perspectives on multiple scales and levels of decision-making (multi-level governance, polycentricity, politics of scale) to fruitfully study forest conflicts. Furthermore, the thesis provides empirical insights about forest conflicts in the face of energy transition and climate change. Based on the theoretical and empirical findings, this thesis provides practical recommendations to policy makers and practitioners on how to improve governance in forestry and the management of other natural resources. For example, this thesis shows the importance of considering different actor constellations in participatory processes at different governance levels, and that not every actor will react the same way to a certain method of decision-making. Furthermore, this thesis illustrates how trust building measures, such as enhanced communication between stakeholders, transparency in decision-making and forest education can reduce the risk of destructive conflict escalation. This thesis also demonstrates that energy transition and the discussion about climate change are sources of new conflicts, can change old conflicts, and add new, additional levels to forest governance. Thus, climate change and energy transition cause further fragmentation of forest governance and make forest governance more multi-level, create additional venue-shopping opportunities, and bring new actors into forest governance, causing new power constellations in the policy field. Forest governance is in a reconfiguration process which can be conceptualized as shift towards multi-level governance. Level choice and the relation of state and non-state actors in decision-making are important aspects of governance, thus the theoretical approach has yielded valuable insights in forest conflicts and the importance of scale construction in conflict discourses can be illustrated. Different levels are associated with different functions, strengths, and weaknesses of stakeholders; the perceptions of appropriate scale choice are often based on frames. The empirical findings have shown that level choice is often a normative and/or cultural decision, often no objective ´best´ decision-making level exists. Some actors consider different competing, overlapping, and nested decision-making levels to be an opportunity for interest realization; others feel helpless and overwhelmed in complex, multi-level systems. Different re-scaling strategies (up-scaling, down-scaling, fit re-scaling) are applied by actors to realize their interests. Non-state actors have an important function in linking processes from different levels. However, multi-level governance and related concepts have their limits for the explanation of forest conflict processes because some important factors cannot be captured with this approach. For example, social-psychological factors and conflict frames are important for the understanding of conflict development and governance and at a local level individual action and the relations between individuals crucially set the preconditions for the governance of conflicts.
Prospective students´ choice of their university is a topic of rising relevance worldwide. As competition on the higher education market and the resultant fight for students increases, universities need to deal with questions of how, when, and why young people decide where to study. This knowledge forms the basis for developing adequate and effective communication strategies enabling university marketers to recruit the best and most suitable students for their institutions. Despite extensive research on these questions, there still are fundamental gaps like the nonobservance of sense making activities, the neglected role of emotions and higher education policies, the suboptimal choice of research methods as well as problematic theoretical assumptions previous research is based upon. In this dissertation, I address all of these gaps in three complementary articles. In the first paper, I compare American with German research on university choice by focusing on the three aspects of theoretical approaches applied in previous studies, choice factors, and information sources prospective students use. On the basis of this literature review, I identify major research gaps with a focus on, but not limited to, the German context. In the second article, by using the Zaltman Metaphor Elicitation Technique (ZMET), I identify mental models of prospective students that represent their sense making activities. Through this, I get a profound understanding of which rational and especially emotional issues are relevant for the students when they try to make sense of the marketing messages they are confronted with during their university choice process. In the third paper, I challenge the theoretical approaches previous research is based upon by identifying two very different types of decision-makers with their respective choice strategies and logics. Overall, this dissertation contributes to a much more detailed understanding of prospective students´ university choices by identifying their sense-making activities and choice styles, highlighting the role of emotions and context factors, and refining the theoretical foundations university choice research is based upon.
Despite the great progress that has been made in the prophylaxis of oral diseases over the past decades, dental caries and periodontal diseases remain major challenges in the field of dentistry. Biofilm formation on dental hard tissues is strongly associated with the etiology of these oral diseases. Therefore, the process of bioadhesion and biofilm formation on tooth surfaces is of particular interest for dental research. The first stage of bioadhesion on dental surfaces is the formation of the pellicle layer. This mainly acellular film, composed largely of adsorbed proteins, glycoproteins, and lipids, is distinguished from the microbial biofilm (plaque). As the interface between teeth and the oral environment, the pellicle plays a key role in the maintenance of oral health and is of great physiological and pathophysiological importance. On the one hand, the pellicle shows protective properties for the underlying dental hard tissues. On the other hand, it also serves as the basis for dental plaque and therefore, for the development of oral diseases such as caries and periodontitis. Hydrophobic interactions, which are governed by lipophilic substances, are of high relevance for bacterial adherence. Therefore, pellicle lipids, which are a significant constituent of this biological structure, are an interesting target for dental research, as they could modulate oral surfaces, influence microbial interactions, and potentially impede bacterial adherence. Compared to the extensive work on the pellicle´s ultrastructure and protein/amino acid composition, little attention has been given to its lipid profile. Knowledge of the lipid composition of the pellicle may provide insight into several oral pathological states, including caries, dental erosion, and periodontal disease processes and could contribute to novel approaches in preventive dentistry. The principle aim of this thesis was the comprehensive characterization of the fatty acid (FA) profile of the in situ formed pellicle layer. This includes the influence of pellicle maturation on the FA profile as well as intra- and interindividual differences. Furthermore, investigations on the effect of rinses with edible oils on the pellicle´s FA composition were a focus of this work. For these purposes, an analytical method based on a combination of innovative specimen generation and convenient sample preparation with sensitive mass spectrometric analysis was successfully developed and comprehensively validated within this thesis. Pellicle samples were formed in situ on bovine enamel slabs mounted on individual upper jaw splints. After a comprehensive sample preparation, gas chromatography coupled with electron impact ionization mass spectrometry (GC-EI/MS) was used in order to characterize qualitatively and quantitatively a wide range of FA (C12-C24). The individual FA profiles of pellicle and saliva samples collected from ten research participants were investigated. The relative FA profiles of the pellicle samples gained from the different subjects were very similar, whereas the amount of FAs showed significant interindividual variability. Compared to the pellicle´s characteristic FA profile, higher proportions of unsaturated FAs were detected in the saliva samples, highlighting that FAs available in saliva are not adsorbed equivalently to the pellicle layer. This, in turn, shows that pellicle formation is a highly selective process that does not correlate directly with salivary composition. Additionally, pellicle samples collected after 3, 30, 60, 120, and 240 min of intraoral exposure were analyzed. It could be shown that pellicle maturation has only a minor impact on the FA composition. However, the FA content increased substantially with increasing oral exposure time. Modifying the pellicle´s lipid composition by using edible oils as a mouthwash could alter the physicochemical characteristics of the pellicle and strengthen its protective properties by delaying bacterial adhesion. Therefore, the impact of rinses with safflower oil on the pellicle´s FA composition was determined. The application of rinses with safflower oil resulted in an accumulation of its specific FAs in the pellicle, thus representing a possibility for modifying the pellicle´s lipid profile. The present work is the first to apply a validated method that combines in situ pellicle formation, sample preparation, and the comprehensive determination of FAs via a sensitive analytical method. The results provide valuable information regarding the pellicle´s FA composition which closes an existing knowledge gap in pellicle research. A broader knowledge of the lipid composition of the pellicle contributes to the understanding of oral bioadhesion processes and may help facilitate novel approaches in preventive dentistry.