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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.
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.
A central aspect of sustainability governance is collaboration, which has been lauded for its benefits but also criticized for its challenges. The potential benefits of collaboration have apparently been recognized also in the context of EU agriculture. Yet, there has been a lack of holistic consideration of how collaboration can be systematically integrated and promoted in the governance of EU agriculture. Sustainable agriculture cannot only be encouraged through changes in the overall governance system but also through the support of existing and emerging small-scale collaborative initiatives for sustainable agriculture. Indeed, there has been substantial research on the conditions that influence success of similar collaborative initiatives. However, the knowledge resulting from this research remains rather scattered and does not allow for the identification of overall patterns. Additionally, little of this research specifically focuses on sustainable agriculture. What is more, the promotion of collaboration for sustainable agriculture is further complicated by the lack of clarity of the meaning of sustainable agriculture, which is an inherently ambiguous and contested concept. This cumulative dissertation aims to address these gaps by contributing to a better understanding of how collaboration can be facilitated and designed as a means to govern for and advance sustainable agriculture. For this purpose, the dissertation addresses three sub-aims: 1) Advancing the understanding of the concept of sustainable agriculture; 2) scrutinizing the current governance system regarding its potential to facilitate or hamper collaboration; 3) assessing conceptually and empirically how actor collaboration can be facilitated as a means to govern for sustainable agriculture, both from a top-down and a bottom-up perspective. In doing so, this dissertation focuses on EU agriculture and applies a mix of methods, ranging from qualitative to quantitative dominant. The findings of this dissertation highlight that collaboration has been underappreciated and even hampered as an approach to governing for sustainable agriculture. In contrast, this dissertation argues that collaboration offers one promising way to promoting and realizing agriculture and emphasizes the need to integrate different approaches to collaboration and to sustainable agriculture.
In sub-Saharan Africa, women own or partly own one third of all businesses, thereby having a large potential to contribute to the economic development and societal well-being in this region. However, women-owned businesses tend to lag behind men-owned businesses in that they make lower profits, grow more slowly, and create fewer jobs. To identify reasons for this gap and effective means to promote women entrepreneurs, large parts of the entrepreneurship literature have compared male and female entrepreneurs with regard to individual characteristics, paying only limited attention to the underlying environmental conditions. This is problematic as women entrepreneurs operate under different conditions than men, with particularly pronounced differences in sub-Saharan Africa. Against this backdrop, the goal of this dissertation is to contribute to a more profound understanding of women entrepreneurship in sub-Saharan Africa and its promotion through training by examining critical context factors. Specifically, the author analyzes two context factors that influence women's entrepreneurial performance and the success of training interventions: 1) women entrepreneurs' husbands and 2) the entrepreneurship trainer. These analyses are embedded in considerations of the cultural, social, and economic conditions women entrepreneurs in sub-Saharan Africa are facing. In Chapter 2, the author conducts a systematic literature review on spousal influence in entrepreneurship and identifies six recurrent types of influence. Complementing the literature originating from Western settings, she develops propositions on how the sub-Saharan context affects husbands' influence on women entrepreneurship in this region. In Chapter 3, she builds on a cultural theory and an economic theory of the household to develop and empirically test a theoretical model of husbands' constraining and supportive influences on women entrepreneurship in sub-Saharan Africa. The empirical results point to three distinct types of husbands that differ significantly in their impact on women entrepreneurs' business success. In Chapter 4, the author explores the influence of the trainer on the effectiveness of entrepreneurship training in sub-Saharan Africa by drawing on an unsuccessful training implementation. Qualitative analyses indicate that the use of adequate teaching methods is critical towards training success.
Space-related science and technologies affect our daily life. Many countries have already formulated national space regulations to regulate their space activities. China, as one space-faring country, has obtained several achievements in space science and technologies. In recent years, Chinese private space companies have sprung up quickly, which requires a stable and foreseeable legal framework to ensure development. However, compared to the other space powers, China is the only one that has not enacted any formal national space laws. Against the background of strengthening the rule of law in China, research on China's domestic space legislation is valuable and significant. The purpose of this thesis is two-fold. First, to find the legal basis and necessity of national space legislation and to extract the basic content of the existing national space legislation, simultaneously, to identify the new developments in the content of other States´ legislative practices. Second, based on the study of national space legislation, to propose the essential content of China's space legislation.
This thesis aims to provide a quantitative, cross-nationally comparative, longitudinal and multilevel study of the drivers and hindrances of national governments' anti-trafficking measures. In this research, both macro-level determinants of anti-trafficking enforcement and micro-level foundations of human trafficking are explored. In the manuscript, large-N comparative research examines how characteristics of countries interact with people's attitudes towards violence to better understand what creates environments that are more or less supportive of governments' anti-trafficking efforts. The results presented in the thesis speak not only in favor of studying this topic systematically and cross-nationally, addressing existing gaps in the literature but also in favor of combining macro- and micro-level evidence for developing more effective policy responses against human trafficking.
This dissertation examines how smallholder farming livelihoods may be more effectively leveraged to address food security. It is based on empirical research in three woredas (districts) in the Jimma Zone of southwestern Ethiopia. Findings in the chapters that follow draw on quantitative and qualitative data. In this research, the author focuses on local actors to investigate how they can be better supported in their roles as agents who have the ability to improve their livelihoods and achieve food security. This general aim is operationalized through three research questions: (i) How do livelihood strategies influence food security?; (ii) What livelihood challenges are common and how do households cope with these?; and (iii) How do social institutions, in which livelihoods are embedded, influence people's abilities to undertake livelihoods and be food secure? Using quantitative data from a survey of randomly selected households, the author applied a number of multivariate statistical analysis to determine types of livelihood strategies and to establish how these strategies are associated with capital assets and food security. Here she views livelihood strategies as a portfolio of livelihood activities that households undertake to make a living. The predominant livelihood in the study area was diversified smallholder farming involving mainly the production of crops. Based on their analyses, the authors found five types of livelihood strategies to be present along a gradient of crop diversity. Food security generally decreased with less crops being part of the livelihood strategy. The livelihood strategies were associated with households' capital assets. The status of food (in)security of each household during the lean season was measured using the Household Food Insecurity Access Scale (HFIAS). A generalized linear model established that the type of livelihood strategy a household undertook significantly influenced their food security. Other significant variables were educational attainment and gender of household head. The findings contribute evidence to the benefits of diversified livelihoods for food security. Smallholder farming in southwest Ethiopia is beset with process-related and outcome-related challenges. Here, a process-related challenge pertains to the lack of different types of capital assets that people need to be able to undertake their livelihoods, while an outcome-related challenge pertains to lack of food. The most frequently mentioned process-related challenges were associated with the natural capital either as lack in necessary ecosystem services or high levels of ecosystem disservices. Farming households typically faced the combined challenges of decreasing soil fertility, land scarcity, die-off of oxen due to diseases, and wild animal pests. Lack of cash was also common. The findings indicate that when households liquidate a physical asset in order to gain cash, the common outcome is an erosion of their capital asset base. On the other hand, when households drew on their social capital, they tended to maintain their capital asset base. Human capital, for example, in the form of available labor was also important for coping. Protecting and enhancing natural capital is needed to strengthen the basis of livelihoods in the study area, and maintaining social and human capitals is important to enable farming households to cope with challenges without eroding their capital asset base. Smallholder farming in southwest Ethiopia is embedded in a social context that creates differentiated challenges and opportunities. Gender is an axis of social differentiation on which many of the differences are based. The currently ruling Ethiopian political coalition has put important policy reforms in place to empower women. Local residents reported notable changes related to gender in the last ten years. To make sense of the changes, the authors adapted the leverage points concept. Using this concept, the authors classified the reported changes as belonging to the domains of visible gaps, social structures, and attitudes. Importantly, changes within these domains interacted. The most prominent driver of the changes observed was the government's emphasis on empowering women and government-organized interventions including gender sensitization trainings. The changes toward more egalitarian relationships at the household level were perceived by local residents to lead to better implementation of livelihoods, and better ability to be food secure. The study offers the insight that while changing deep, underlying drivers (e. g. attitudes) of systemic inequalities is critical, other leverage points such as formal institutional change and closing of certain visible gaps can facilitate deeper changes (e. g. attitudes) through interaction between different leverage points. This can inform gender transformative approaches. While positive gender-related changes have been observed, highly unequal gender norms still persist that lead to women as well as poor men being disadvantaged. Social norms which provide the basis for collective understanding of acceptable attitudes and behaviors are entrenched in people's ways of being and doing and can therefore significantly lag behind formal institutional changes. Norms influenced practices around access and control of capital assets, decision-making, and allocation of activities with important implications for who gets to participate, how, and who gets to benefit. To more effectively leverage smallholder farming for a food secure future, this dissertation closes with four key insights namely: (1) Diversified livelihoods combining food and cash crops result in better food security; (2) Enhancing natural and social capital is a requisite for viable smallholder farming; (3) Social and gender equality are strategically important in improving livelihoods and food security; and (4) Institutions particularly social norms are key to achieving gender and social equality.
This thesis deals with the influence of sustainability communication on the purchase decision of sustainable tourism products involving German specialist tour operators. Sustainability communication is a challenge, because sustainable tourism is an abstract and vague concept which consumers find it difficult to grasp and about which they are sceptical. The service characteristics of tourism products complicate the decision making stage, which is a high-involvement situation of uncertainty to which sustainable product attributes add complexity. As an introduction, an interdisciplinary theory discussion reveals knowledge gaps in terms of the value-belief-norm theory and the elaboration likelihood model (ELM). The first article, which is the first systematic literature review on the topic, reveals that there is a limited theoretical understanding of sustainability communication, a lack of practical understanding of how to design sustainability messages, and an inadequate set of methodologies for its research. It identifies knowledge gaps concerning: the holistic approach to sustainability communication; its role in the attitude-behaviour gap; an interdisciplinary theoretical understanding focusing on belief-based social psychological theories and theories of persuasion; qualitative methods; and experimental design. The second article investigates the role of sustainability communication in the attitude-behaviour gap, employing the value-belief-norm theory to explain how information is processed by special interest customers. Interview findings show that ineffective sustainability communication is the reason for the gap and that customers unintentionally booked sustainably. The study identifies eight groups of beliefs which explain the processing of sustainability attributes. Sustainability information is effective when it is value-congruent, that is, when customers perceive they can make a difference, they begin to ascribe a responsibility to themselves. The third article investigates how to design an effective sustainability message in tour operator advertising. Drawing on the ELM, the study shows that appeal type does not significantly influence persuasion but the topic presented is important. Cultural sustainability is the sustainability topic that is most persuasive for cultural tourists, while consumer prior knowledge and issue-involvement with the topic promote successful information processing.
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.
This cumulative thesis extends the econometric literature on testing for cointegration in nonstationary panel data with cross-sectional dependence. Its self-contained chapters consist of two publications and two publication manuscripts which present three new panel tests for the cointegrating rank and an empirical study of the exchange rate pass-through to import prices in Europe. The first chapter introduces a new cointegrating rank test for panel data where the dependence is assumed to be driven by unobserved common factors. The common factors are first estimated and subtracted from the observations. Then an existing likelihood-ratio panel cointegration test is applied to the defactored data. The distribution of the test statistic, computed from defactored data, is shown to be asymptotically equivalent to that of a test statistic computed from cross-sectionally independent data. The second chapter proposes a new panel cointegrating rank test based on a multiple testing procedure, which is robust to positive dependence between the individual units' test statistics. The assumption of a certain type of positive dependence is shown by simulations not to be violated in panels with dependence structures commonly assumed in practice. The new test is applied to find empirical support of the monetary exchange rate model in a panel of eight OECD countries. The third chapter puts forward a new panel cointegration test allowing for both cross-sectional dependence and structural breaks. It employs known individual likelihood-ratio test statistics accounting for breaks in the deterministic trend and combines their p-values by a novel modification of the Inverse Normal method. The average correlation between the probits is inferred from the average cross-sectional correlation between the residuals of the individual VAR models in first differences. The fourth chapter studies the exchange rate pass-through to import prices in a panel of nineteen European countries through the prism of panel cointegration. Empirical evidence supporting a theoretical long-run equilibrium relationship between the model's variables is found by the newly proposed panel cointegration tests. Two different panel regression models, which take both cointegration and cross-sectional dependence into account, provide most recent estimates of the exchange rate pass-through elasticities.