Open Access

This thesis makes an important contribution to better understanding biodiversity and ecosystem function relationships across trophic levels in forests - aspects that are still underrepresented in BEF research. Ongoing biodiversity loss can be expected to change important trophic interaction pathways in these ecosystems, making increased efforts in exploring the mechanisms underlying, and the drivers determining, the impact of trophic complexity on the relationships between biodiversity and ecosystem functioning a crucial objective for holistic approaches to BEF research.

The dissertation project focuses on empirically investigating consumers´ attitudes, motiva-tions and purchasing decisions regarding sustainable products. The focus on this micro per-spective, however, does not reflect consumers´ roles within the transformation towards sus-tainable 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 purchas-ing behavior and reveals the potential of integrating such insights into the management of transformations towards sustainable consumption.

Uganda has been plagued by political instability in the past and wide spread abuse of human rights coupled with failed economic policies. However, the country has witnessed increased economic growth and the government has embarked on several poverty eradication programmes despite rising income inequalities and poverty in the country. The task of ensuring poverty as a human right in the country has not been an easy one for those charged with the duty of ensuring the right to freedom from poverty. This research examines the complexity of attaining the right to freedom from poverty in a country like Uganda. This study will also give a philosophical view on poverty and human rights and those responsible for ensuring the implementation of this right. Through the analysis, the research examined the key challenges faced in attaining the right to freedom from poverty in Uganda, discussed how poverty was defined through different perspectives. The information provided in the analysis is further examined by putting the theoretical findings in correspondence with the gathered empirical information for more definitive results of the study. The fundamental results and conclusion of this research revealed the overall challenges faced in regarding poverty as a human right which include how poverty is defined, the mindset, the political history of Uganda and so on. However, the study has recommended extensive research into the role of the family in ensuring poverty as a human right and further research in the effectiveness of the laws in Uganda in ensuring poverty as a human right.

Summary Since the early 2000s, ecosystem services strongly gained significance as a research topic. While the number of papers strongly increased, the concept was further developed which changed the way it was applied. From highlighting the value of ecosystems by viewing them not only from an ecological, but also from an economic perspective in the beginning, it is nowadays, among others, used to map and calculate the monetary value of ecosystem services. Lately, the International Panel on Biodiversity and Ecosystem Services (IPBES) further developed the concept into Nature’s contributions to people (NCP) which puts a stronger emphasis on stakeholders and indigenous knowledge. However, so far none of the conceptual developments managed to integrate the temporal dimension of ecosystem services into this concept, although this should be the basis for a sustainable long-term management of ecosystems and their services. Therefore, I present three articles in this thesis that deal with temporal aspects of ecosystem services. In two of them I also present a proposal for a framework for the classification of ecosystem services based on their temporal dynamics. In this dissertation I differentiate 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 that I present, 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, illustrated by the concepts of transformation, transition, and regime shift. 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, I conclude 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. In most articles that do account for temporal aspects, the focus is strongly on the side of ecological supply of ecosystem services rather than on the demand-side which leads to the exclusion of stakeholder perceptions and therefore, makes it impossible to connect ecosystem service demand and supply over time. Moreover, the concept of change that is used most often in the literature is that of regime shifts which comes from a purely ecological background and focuses mostly on changes that happened in the past. This neglects the possibility of change towards a positive outcome in the future. In general, there is a strong disciplinary divide in the concepts and terminology used. This leads to a lack of exchange between different scientific disciplines and non-academic stakeholders. Approaches that are needed to solve problems of ecosystem service management are therefore impeded. To enable future research to better account for temporal aspects and connect supply and demand sides of ecosystem services with each other, I give four recommendations for future research. These are (I) take temporal dynamics into account by conducting long-term research, (II) ensure conceptual clarity, (III) create a solution-oriented agenda and (IV) take the demand side into account by involving stakeholders’ perceptions over time. By following these recommendations, future research could help to support the sustainable management of ecosystem services as dynamics will be better known and targeted measures can be implemented.

Many fewer women than men try the entrepreneurial way in Germany. Any explanation for this phenomenon must be complex, as many factors are relevant for its production. Among other things, it is possible to speculate on sexual/gender discrimination, on more or less voluntary decisions of women or on different starting conditions for potential entrepreneurs. We assume that these options are closely related. This paper will concentrate, though, on the third alternative. Its focus will be set on the “family field,” or more precisely, on the role of family law in hindering women from trying self-employment. The family field in Germany has not evolved in the sense of gender equality along with all other areas of society - e.g., entrepreneurship. No gender equality is possible if the family field is not part of it. This paper analyses causes and consequences for this phenomenon. Key Words: Gender studies, Family Law, Entrepreneurship, chance equality, social sustainability

Abstract. The ecological literature suggests that biodiversity reduces the variance of ecosystem services. Thus, conservative biodiversity management has an insurance value to risk-averse users of ecosystem services. We analyze a conceptual ecological-economic model in which such management measures generate a private benefit and, via ecosystem processes at higher hierarchical levels, a positive externality on other ecosystem users. We find that ecosystem management and environmental policy depend on the extent of uncertainty and risk-aversion as follows: (i) Individual effort to improve ecosystem quality unambiguously increases. The free-rider problem may decrease or increase, depending on the characteristics of the ecosystem and its management; in particular, (ii) the size of the externality may decrease or increase, depending on how individual and aggregate management effort influence biodiversity; and (iii) the welfare loss due to free-riding may decrease or increase, depending on how biodiversity influences ecosystem service provision.

An empirical analysis of various waves of the ALLBUS social survey shows that union density fell substantially in western Germany from 1980 to 2004 and in eastern Germany from 1992 to 2004. Such a negative trend can be observed for men and women and for different groups of the workforce. Regression estimates indicate that the probability of union membership is related to a number of personal and occupational variables such as age, public sector employment and being a blue collar worker (significant in western Germany only). A decomposition analysis shows that differences in union density over time and between eastern and western Germany to a large degree cannot be explained by differences in the characteristics of employees. Contrary to wide-spread perceptions, changes in the composition of the workforce seem to have played a minor role in the fall in union density in western and eastern Germany.

This doctoral thesis examines how European merger control law is applied to the energy sector and to which extent its application may facilitate the liberalisation of the electricity, natural gas and petroleum industries so that only those concentrations will be cleared that honour the principles of the liberalisation directives (IEMD and IGMD ). In its communication on an energy policy for Europe, adopted on 10/01/2007, the Commission emphasized that a real internal European energy market is essential to meet Europe’s three energy objectives, i.e. competitiveness to cut costs for citizens and undertakings to foster energy efficiency and investment, sustainability including emissions trading, and security of supply with high standards of public service obligations (Art. 106 TFEU). The EU issued three pre-liberalisation directives since the 1990s. Dissatisfied with the existing monopolistic structures, i.e. in Germany through demarcation and exclusive concession agreements for the supply of electricity and natural gas, which were until 1998 exempted from the cartel prohibition provision (§ 1 GWB), and the prevalence of exclusive rights on the energy markets, the Commission triggered infringement proceedings against four member states under Art. 258 TFEU. The CJEU confirmed that the Commission has the power to abolish monopoly rights under certain circumstances and the rulings had the effect of convincing the member states to enter into negotiations for an opening up of energy markets owing to the internal market energy liberalization directives of 1996 / 1998 / 2003 / 2009 / 2019 (IEMD and IGMD) . The core element of the IEMD and IGMD is to abolish exclusive rights and offer primarily at least large industrial electricity and gas consumers to choose their supplier (market opening for eligible consumers) and to grant negotiated or regulated third party access to transmission and distribution grids so to address natural monopolies. The second liberalization package of 2003 brought a widening of market opening and acceleration of pace of market opening to a greater number of eligible customers (all non-household consumers since July 2004 and all consumers since July 2007) and an increase in the provisions on management and legal unbundling. In parallel, two regulations regulate the access to cross-border electricity infrastructure (interconnectors) and the third party access to gas transmission networks. Two further Directives addressed the security of natural gas and power supply and a third deals with energy end use efficiency and services , a fourth dealt with the promotion of co-generation and a fifths covers marine environmental policy (Marine Strategy Framework Directive in combination with the Hydrocarbons-Licensing Directive ) backed by the public procurement directive in the energy sector. A regulation covers energy statistics. The implementation of the second energy package was slow and the Commission launched infringement proceedings against 5 member states in front of the CJEU (Art. 258, 256 TFEU). The 3rd energy package of 2009 addressed ownership unbundling of key-infrastructure ownership and energy wholesale and retail supply consisting of three regulations and two directives, deals with independent regulators, an agency for the cooperation of energy regulators (ACER) and cross-border cooperation (the European Network for transmission system operators for electricity and gas [ENTSO-E/G] and a regulation on cross-border grid access for electricity and natural gas. Another new regulation deals with market integrity and transparency . Hence, new regulations regulate guidelines on electricity balancing, congestion management, long-term capacity allocation, the code for grid access and transmission system operation . Other regulations address the guidelines for a European cross-border energy infrastructure, which has to be interpreted in the context of European environmental impact assessment law, the submission of data in electricity markets, establish a network code on demand connection , rule on a network code for grid access for direct current transmission systems, define guidelines on electricity transmission system operation, regulate a network code on electricity emergency , deal with security of natural gas supply and establish a programme to aid economic recovery by granting financial assistance. Finally, Directives promote the usage of renewable energies, regulate common oil stocks, the safety of offshore oil and gas production and the quality of petrol and diesel fuels. The 4th liberalization package consists of a new IEMD2019 and IGMD2019, of a new regulation on European cross-border electricity trade, of a regulation on risk preparedness in the electricity sector, of a new agency for the cooperation of European energy regulators, addresses energy efficiency and rules on good governance in the energy union. Since 2008, the Art. 194 I-II TFEU governs the ordinary legislation procedure in the energy sector (internal market in energy, security of energy supply, energy efficiency, energy saving, renewable energies, interconnection of energy grids) notwithstanding of unanimous decision making in case of energy taxation matters (Art. 194 III TFEU). A brief analysis of the economic implications of concentrations is followed by an assessment of the evolution of European merger control law under Art. 66 ECSCT, Art. 101 and 102 TFEU, the merger control regulation of 1989 and its significant amendments of 1997 and 2004. Then, the theoretical findings are contrasted to the results of recent merger proceedings in the energy sector with a focus on the VEBA/VIAG decision. Several deficiencies are established which limit the efficacy of merger control as a tool of offsetting shortcomings in the secondary EC law with regard to the liberalisation of the electricity and gas supply industry (IEMD and IGMD). Commitments proposed by the parties of a given concentration and accepted by the Commission as being sufficient to remedy a serious potential of dominance may only be of subsidiary relevance to the liberalisation of sectors owing to a number of analytical and practical drawbacks. One dominant drawback relates to the fact that the commitments depend always on parties' proposals and can never be imposed ex officio. Others relate to the blunt authorisations provided by the wording of Art. 6 and 8 MR1997 and MR2004 as to the implementation of undertakings. With regard to acquisitions of U.K. regional electricity companies by EdF, it is elaborated that the current merger control law leaves no scope for reciprocity considerations regarding acquisitions by incumbent companies in liberalised markets even though the acquirer is a protected public undertaking. Moreover, it is established that different decisions apply inconsistent market definitions. By means of the VEBA/VIAG and RWE/VEW cases, the question is addressed which causes are responsible for the established analytical and practical deficiencies of merger control in the energy sector. It is stated that the weaknesses of the IEMD 2009/72/EC and IGMD 2009/73/EC are partly responsible for weak undertakings which do not sufficiently remove the scope for dominance on the affected markets and which do not rule out any possibility of impediments of effective negotiated or regulated TPA and do not remove any commercial incentive of the grid subsidiaries of the vertically integrated companies as to access which discriminates between intra and extra group applicants. It is reported that another argument relates to the limited scope that the Commission has if it wants to remedy deficiencies of written primary law owing to the extraordinary nature of the implied powers doctrine based on the principle of constitutional state. Adverse political influence against competition authorities is also judged. Further, it is analysed that accidental regulation based on incidental provisions imposed on undertakings which may or not implement a concentration is by no means a consistent and non-discriminatory and predictable tool to overcome drawbacks of primary or secondary European law in a given sector owing to the democratic principle and the constitutional state doctrine. It is discussed that secondary legislation with regard to energy networks is inter alia restricted by Art. 345 TFEU and provisions of national constitutions which protect property rights against dis-proportionate expropriations or re-definitions of property. Further, legal authorisations of said calibre will have to be connected to a system of state liability law. Adverse political pressures are considered. The same is true for egoistic national policies which abstain from transnational task forces in order to settle difficulties and disputes. Furthermore, the adverse effect of different stages of the maturity of domestic markets, different consumer patterns and a potential isolation of the system is not neglected, because these conditions make it more difficult to apply consistent standards as to the appropriate market definition in order to facilitate harmonisation. The implementation of the VEBA/VIAG merger is discussed, as the former was further complicated owing to specifically evaluated circumstances which were difficult to predict. Nevertheless, the Commission is not exempted from the duty to take due care concerning potential impediments as to the realisation of parties' commitments. In contrast to the negative aspects, it can be highlighted that the Commission quickly realised flaws of the energy liberalisation project as expressed by the present form of the IEMD and IGMD. Consequently, the co-ordinative and innovative mechanisms of Florence and Madrid were created in order to boost the development of effective cross border trade - i.e. tariff systems and interconnector congestion management. It will be concluded that undertakings put forward by the parties and accepted by the Commission should be restricted to a subsidiary legal instrument, only applied if strictly necessary to overcome certain detrimental aspects of given concentrations in order to provide a hint for the legislator, to specify its legislation. Competition as a de-central distributor of risk, wealth and power will be extended to its maximum extent, if wholesale consumers benefit from lower energy prices which allow greater productivity of European products on the world markets in combination with higher environmental standards owing to modern, cost-efficient plants. A successful implementation will be described by liquid spot markets for power accompanied by tools of financial risk management like forwards, futures and options. These will be valuable indicators of efficient liberalisation of the European electricity and gas supply industries.

The Ili Delta in Kazakhstan is an important ecosystem that offers crucial wetland habitats for several bird species. However, the Ili River, the Ili Delta and the Balkhash Lake are suffering from water shortage due to climate change and human activities. The desertification of the Aral Sea, an obvious point of comparison to the Balkhash region, also involved the degradation of wetland habitats and the related loss of many bird species relying on these habitats. Therefore, water shortage at the Ili Delta may also be the reason for the loss of wetland habitats and bird species. In this study, bird species numbers, species abundances as well as bird diversity at different habitats in the Ili Delta were examined. There are many habitat types provided by the Ili Delta, for example reed bed vegetation, Tugay forest, bare soil floodplains along rivers and steppe. The results of this study showed that the central delta region with habitats of submerged reed vegetation showed the highest number of bird species and the greatest diversity. Threatened bird species at the Ili Delta were also observed only in these wetland habitats. Steppe habitats showed the lowest numbers of bird species and the lowest bird diversity. In general, all habitats at the Ili Delta are important for the ecosystem and essential for the bird species that depend on them for their survival. With expansion of arid steppe habitats due to water shortage, however, previous wetland habitats may be lost. Moreover, bird species that depend on these wetland habitats may also be lost. Therefore, protective measures for the Balkhash region in general and the wetland habitats at the Ili Delta and its distinct avifauna in particular are urgently needed.

Forest ecosystems significantly contribute to global carbon (C) sequestration and therefore play a crucial role for climate change mitigation. At the same time, forests were and are subjected to past and current environmental changes with consequences for the functioning of forest ecosystems and their associated ecosystem services. Forests in Central Europe are highly influenced by former settlement activities and land-use changes, as well as silvicultural management measures. Until the beginning of the 19th century anthropogenic activities caused a tremendous decline of the forest area. The resulting timber shortage led to large scale afforestations on previously agriculturally used land (e.g. heathlands, grasslands and croplands) 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 addition, most forests in Central Europe are under silvicultural management, while the knowledge about the consequences of management measures on forest ecosystem functioning, particularly in the face of ongoing global environmental changes, is also still limited. 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 with a forest continuity > 230 years versus recent forests afforested on former arable land ~ 100 years ago) 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.