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Wood-pastures have been present in Europe for thousands of years. This form of grazed landscape, combining herbaceous vegetation with trees and shrubs, has often co-evolved with its human users into complex social-ecological systems (SES). Wood-pastures are associated with high cultural and biodiversity values and are an example of the sustainable use of resources. However, due to their often relatively labour-intensive management and low productivity, large areas of wood-pastures have been lost over the last century. The loss of these areas means not only the loss of biodiversity on both local and landscape scales, but also the loss of traditional farming and cultural heritage in some regions. Across the European Union, wood-pastures are facing different problems and are embedded in different social systems and ecological environments. Yet they are all affected by global change and common European policies. To understand the challenges for wood-pastures in a changing world, a holistic approach combining different disciplines is needed. This dissertation therefore is analyzing wood-pastures across Europe as a Social-ecological System, combining ecology and social science with the aim to identify the barriers and drivers for wood-pastures persistence into the future.
A solid knowledge about nature is essential to understand the consequences of biodiversity loss, the limitation of natural resources and the need for a sustainable development. Inspired by these challenges, the researcher investigated in her dissertation seed predation, an important ecosystem function, as part of citizen science project. As seed predation has only rarely been investigated along urban-rural gradients and to integrate the question if the background (urban vs. rural) of primary school children affects their environmental knowledge, she selected study sites in and around Lüneburg and Hamburg, in Northern Germany. In her ecological experiments, it was found that slugs are important seed predators that independently of urbanization predated about 30% of all seeds in the anthropogenically used landscapes investigated. Also, for the first time, primary school children could be integrated in a citizen science approach into this research and it could be shown that even seven year old children can record data as reliable as a scientist. Finally, the researcher investigated the native species knowledge from the children taking part as citizen scientists in her research, considering possible differences due to their urban or rural background. Contrary to her expectation, the urban or rural background had no significant effect on the species knowledge. However, the work provides a good foundation to transfer the approach of introducing a basic foundation of a taxonomical species concept in primary school to foster further understanding on biodiversity and ecosystem functions.
Internet- and mobile technologies are increasingly used to deliver mental health care. E-Mental Health is promising for the prevention and treatment of mental disorders. However, while E-Mental Health was shown to be an effective treatment tool, fewer studies investigated the prevention of mental health problems with E-Mental Health approaches. In a series of three studies, this dissertation examines internet- and mobile-based approaches for the early monitoring and supporting of mental health. First, a pilot study investigates the use of smartphone data as collected by daily self-reports and sensor information for the self-monitoring of bipolar disorder symptoms. It was found that some, but not all smartphone measurements predicted clinical symptoms of mania and depression, indicating that smartphones could be used as an earlywarning system for patients with bipolar disorder. Second, a randomized controlled trial evaluates the effectiveness of an internet-based intervention among persons with depression and sickness absence. The intervention was found to be effective in reducing depressive symptoms compared to a control group, suggesting that the internet can provide effective support for people with sickness absence due to depression. Third, a study protocol proposes to combine self-monitoring with a mobile intervention to support mental health in daily life. Supportive self-monitoring will be evaluated in a fully mobile randomized controlled trial among a sample of smartphone users with psychological distress. If supportive self-monitoring on the basis of a smartphone application is effective, it could be widely distributed to monitor and support mental health on a population level. Finally, the contribution of the presented studies to current research topics in E-Mental Health is discussed.
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.
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.
Various researchers have been hypothesizing on and agreeing that, in negotiations, resources play a fundamental role in parties' behaviors and outcomes. Paradoxically, empirical findings that provide insights into the effects of resources are scarce. The current research seeks to shed light on the overwhelming consensus that resources may shape negotiations. Specifically, in a series of four original research articles, we systematically examine the overarching question of how tangible and even intangible resources affect parties' attitudes, behaviors, and outcomes. Resources in negotiations can be characterized as all the tangible and intangible aspects of the negotiation that are related to the negotiators' interests. Thus, the central activity of the bargaining relationship is the allocation of tangible resources, while intangibles are simultaneously involved. Consistent with this basic idea, we assume that whether parties focus on catching hold of obtaining their adversaries' tangible resources or on losing grip of their own tangibles impacts their concession behavior and outcomes. Parties with a focus on losing their own tangible resources should experience more loss aversion, concede less, and should achieve better outcomes than parties who focus on catching hold of obtaining their counterpart's tangibles. It follows that what should be essential in the ongoing negotiation process should apply to the first move at the bargaining table as well. When first-movers lead responders to focus on catching hold of tangible resources, the well-documented anchoring effect should occur, benefitting the first-mover. Contrarily, when the first-mover induces a focus on the resource the responder is about to lose, responders should be motivated to adjust their counterproposal far away from the opening anchor. Responders' motivation to adjust should leverage the anchoring effect in negotiations. Further, we outline the very special role of money in negotiations, that is perceived as likely the most important tangible resource. Ultimately, we address the important role of intangible resources, in addition to that of tangible resources, and suggest that the intangible resource of professional experience is related to the negotiator´s attitudes towards unethical bargaining tactics. Overall, the findings of these research projects suggest that not only tangible but also intangible resources do in fact have the fundamental impact on negotiators' behavior and outcomes that has been hypothesized for a long time. Parties who focus on losing grip of their own tangible resources concede less and are better off at the end of the negotiations than parties who focus on catching hold of their counterparts' resources. The researchers report evidence for this basic finding, from the first move at the bargaining table to the final agreement. Their findings help to better understand the key role of money in negotiations and to highlight the "mythical" components of this legendary resource. In addition to the findings on tangible resources, the study reveals a strong negative relationship between negotiators' intangible resource of professional experience and their tendency to endorse unethical bargaining tactics. The research work concludes that losing tangible resources and keeping sight of intangible resources may have profound effects on parties' negotiation attitudes, behaviors, and outcomes.
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).
Derivatives are contracts between two parties, a buyer and a seller. The contract will be fulfilled in some point in the future at a predetermined price. The value of those contracts is based on an underlying entity which can be a traded asset or even the weather. Derivatives contain chances, but also risks, investor should be aware off. This thesis aims to deeply analyze two derivative products in the German market and one risk for each which influences the prices of those products. The first part of this thesis focuses on warrants and the issuer's credit risk involved. It finds evidence that the issuer's credit risk influences the connection between warrant characteristic and its prices. Over time this connection is unstable partly driven by the issuer's credit risk. The second paper of this thesis shows that issuers seem to use their credit risk systematically to influence warrant prices. Evidence is found that the changes in credit risk are not fully included in the prices directly, but that the adjustment to the new level of credit risk takes several days. In addition, the issuer's adjustment to changes in credit risk are different for credit risk increases than for credit risk decreases. Especially after financial crisis, in more stable times, evidence is found for such adverse pricing pattern. The third part of the thesis focuses on energy derivatives traded at the Europe Energy Exchange and analyses the influence of weather parameters on energy derivatives with different load profiles and time horizons. This part of the thesis finds that especially wind speed and sun hours have a strong influence on energy derivatives. However, not all products are influenced in the same manner. Products with a longer time horizon are influenced less than the product with a short horizon. Moreover, products comprising hours of the day where energy consumption is expected to be higher are influenced stronger than products comprising hours of a day with lower time consumption. The thesis shows that derivatives are not alike and that it is needed for future research to differentiate between products and the risks which are involved. Since even though we classify them all as derivatives the risks influencing the derivative´s prices do vary tremendously.
Financial Decisions in Family Firms. Private Equity Investors, Capital Structures and Firm Identity
(2017)
This paper-based dissertation deals with financial issues of family businesses. These businesses are mainly characterized by the overlapping of the two social systems: family and business. Thus, the involvement of an owner family can have a significant impact on corporate decision-making, for instance in terms of corporate finance decisions. In Germany, the latter is dominated by a strong orientation towards banks. Nevertheless, the relevance of external equity, as source of funding, has increased during the last years due to regulatory interventions (Basel III) and a growing number of alternative private equity providers. Against this backdrop, the present dissertation and its four papers examine different research questions in the context of capital structure decisions of family firms. These decisions are related to external equity as well as debt financing. The first paper is a structured literature review concerning the interaction of family firms and external equity investors. The paper analyzes the current state of knowledge and points out directions for future research, which is particularly relevant for a young and recently growing field of research. The second paper is a conceptual paper that deals with the differences of various types of private equity investors from the perspective of family firms looking for funding. The literature review paper revealed that existing studies so far neglected the topic of heterogeneity among investor types. Thus, the second paper represents a first attempt to close this research gap. Paper three also takes up a research gap identified by the first paper and examines the exit of private equity minority investments in family-owned businesses. The paper applies a qualitative empirical research design, which includes fourteen cases and related six interviews. The results reveal that the disinvestment phase of private equity investors only rarely leads to conflicts with owner families. The fourth paper uses a quantitative research design with a comprehensive dataset of 691 companies. The paper aims to compare the capital structures of large family and non-family firms. Overall, the findings show that family firms have significantly higher overall and long-term debt levels compared to their non-family counterparts. The identity as a family firm, which leads to a leap of faith by banks, can be a possible explanation for these results.
This work investigates how managers/consultants (practitioners) of different ranks are engaged in patterns of behavior (practices) in socially situated contexts (practice) attempting to shape preferred shared interpretations of reality to achieve their goals. Following this line of inquiry, the work aims at (1) advancing our understanding of the role of practitioners in shaping managerial realities and (2) investigating how practitioners actually shape managerial realities, particularly focusing on "reality-shaping" practices and their content. The dissertation comprises a set of four complementary articles investigating these research questions empirically based on in-depth, empirical case studies and theoretically within various managerial contexts (client-consultant relationship, CEO post-succession strategic change process, evolutionary initiative development) and considering different actor perspectives (top managers, middle managers, consultants and clients). Resulting from this variety, the articles rely on and contribute to different, at times distant, research fields and therewith scholarly discussions. However, the literature on sensemaking and sensegiving offers a suitable overarching theoretical frame which is used in this work to synthesize the key contributions of the four articles.