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The principle of sustainability contains two objectives of justice regarding the conservation and use of ecosystems and their services: (1) global justice between different people of the present generation ("intragenerational justice"); (2) justice between people of different generations ("intergenerational justice"). International sustainability policy attaches equal normative importance to both objectives of justice. Accordingly, environmental philosophers ethically justify that people living today and people living in the future have equal rights to certain basic goods, including ecosystems and their services (e.g. Feinberg 1981, Visser’t Hooft 2007). Whereas ideal theories of sustainability and justice do not recognize interdependencies between intragenerational and intergenerational justice, conflicts in attaining the justices possibly arise in policy implementation. Identifying and preventing such conflicts is fundamental to devise an ethically legitimate, politically consistent and actually effective sustainability policy. This dissertation systematically investigates conflicts between intragenerational and intergenerational justice in the use of ecosystem services. Human wellbeing depends on the services provided by ecosystems. Yet, humans substantially degrade world’s ecosystems, and therewith cause the loss of important ecosystem services (MEA 2005: 26ff.). The idea of sustainability demands to use ecosystem services in accordance with the two objectives of intragenerational justice and intergenerational justice. Reality, however, is far from attaining these objectives: Both today’s global poor and future persons are, resp. will be, disproportionately affected by the loss of vital ecosystem services (MEA 2005: 62, 85). Especially severe affected are the rural poor who directly depend on local ecosystem services for food, income and health. The political discourse on the relationship between the objectives of intra- and intergenerational justice in the use of ecosystem services (‘justice-relationship’) is blurred. Further, the political discourse lacks a common understanding of justice in ecosystem-use and a systematic reflection on the actual ‘justice-relationship’, such as on the factors that cause conflicts between the two justices. In this dissertation, I investigate the ‘justice-relationship’ along three central questions: • What conception(s) of justice can adequately address the distribution of access rights to ecosystem services? • How must sustainability policy be designed to enhance both intragenerational and intergenerational justice in the use of ecosystem services? • (How) Can economics be helpful for characterizing and assessing trade-offs between the two justices? I approach these questions both generally and by the example of a case study, the MASIPAG farmer network in the Philippines. Methodologically, I combine a normative and a positive analysis of the relationship between intra- and intergenerational justice in the use of ecosystem services: The normative analysis serves the explication, justification and reflection of the norms underlying the ‘justice-relationship’; the positive analysis serves the description of the ‘justice-relationship’ in the sustainability discourse and in practical contexts, as well as the provision of explanations on the determinants of the ‘justice-relationship’. As methodological approach, I apply the “comprehensive multi-level approach” as developed by Baumgärtner et al. (2008) – investigating the ‘justice-relationship’ simultaneously on the three levels of (i) concept, (ii) model and (iii) case study.

The challenges of sustainable development have spurred the complexity of management reality, unveiling considerable risks and opportunities for companies. The past twenty years of development in management science and practice have refined the understanding of the linkages between corporate success and sustainability aspects of business. Nevertheless, numerous management tools and concepts have been criticised for failing to contribute to improved sustainability performance. Management accounting is an indispensable system for generating, preparing and providing information for recognising decision situations and informing decisions. Building on the relevance of information, sustainability accounting has received considerable attention in the past decade. Related research has emphasised the contribution of sustainability accounting to tackling sustainability challenges in specific settings. A systematic investigation of the role of sustainability accounting is virtually non-existent to date. To overcome this limitation and provide an insight into the practice of sustainability accounting and its role in sustainability management and ultimately in corporate success, this doctoral thesis approaches the question How does sustainability accounting contribute to improved information management and management control? The direct contribution is two-fold. First, a number of decision situations are explicated. Examples for such decision situations include utilising certain types of information for specific decisions, engaging various functions in different ways, etc. Making a decision within these decision situations was observed to contribute to achieving corporate goals. Second, the overarching view on the results reveals an interesting pattern. It is the existence of this pattern that supports the view that sustainability accounting can help companies in the pursuit of improved sustainability performance and (thereby) corporate success. The findings enable both practitioners and researchers gain an insight into how sustainability accounting can be deployed so that the company’s limited resources are focused on the crucial decisions in information management and management control. Subsequent recommendations are supported by up-to-date examples. The nature and the scope of the research constituting this doctoral thesis also highlight the path for future research to expand and refine the propositions made herein.

In the light of the concurrent loss of biodiversity, biodiversity and ecosystem functioning (BEF) research attracted a great deal of attention and emerged as one of the important fields of research in ecology. Since important ecological interactions such as competition occur between individuals, the understanding of individual tree growth was considered to be fundamental for forest related BEF research. Individual tree growth is determined by the above- and belowground interactions of a tree individual with its local neighbourhood. To obtain a deeper understanding of BEF relationships, I broadened the focus from individual tree growth (usually measured as diameter or biomass increment) to the arrangement and dynamics of the above-ground modules of trees in dependence of their local neighbourhood. More precisely, the main objective of the present thesis was to analyse the impact of tree diversity on individual tree growth, crown architectural and branch demographic variables. Thereby I considered crown architectural variables as important indicators of the competition for light. In addition, crown architectural variables impacted ecosystem services such as erosion control. Furthermore, the results of the present thesis contributed to the current discussion on species coexistence theories, which may be differentiated by two opposing views: one that relies on neutral processes and one that implicates a role for meaningful differences in the ecological strategy (niche) of co-occurring species. The studied forest ecosystems were the subtropical broad-leaved evergreen forests of southeast China, which have been under high human pressure due to a long history of intensive land-use. The area is of particular interest for BEF research due to the high species richness of woody plants, including many, yet poorly studied species, and due to the rough terrain with steep slopes, which cause severe soil erosion. The present thesis combines three observational with two experimental studies, applying the local neighbourhood approach along an age gradient from tree saplings to mature trees. In the Gutianshan National Nature Reserve (GNNR), I conducted two observational studies on permanent plots which were chosen according to a space-for-time substitution design. The aim of the first study was to reveal the effects of diversity (species richness, functional diversity) together with other biotic and abiotic variables on morphological growth parameters (crown area, crown displacement and stem inclination) of target trees of four tree species (Castanea henryi, Castanopsis eyrei, Quercus serrata and Schima superba). In the second study, the same target trees together with their neighbours were used to analyse the relation between stand related functional diversity and the horizontal and vertical structure of the canopy. The third study was conducted in a young secondary broad-leaved evergreen forest. Using two target species (Castanopsis fargesii and Quercus fabri), the role of diversity, intra- vs. inter-specific competition and the mode of competition (symmetric vs. asymmetric) on the target individuals was tested by analysing five-year radial growth increments. The two other studies were carried out in an experimentally established plantation, using saplings of four tree species (C. henryi, Elaeocarpus decipiens, Q. serrata and S. superba), which were planted in monoculture, twoand four-species combinations and in three densities. The fourth study focused on mechanisms of coexistence and the role of species richness, species composition, species identity and density on sapling growth. The fifth study tested the effect of sapling density and identity on the througfall kinetic energy, which represents a measure for the erosive power of rain. It was found that functional diversity does affect crown architectural and canopy related parameters of forests in the GNNR. However, no effects of species richness on radial-growth were detected in the younger forest. Since I also did not find strong effects of species richness on saplings in the experimental plantation, diversity effects may evolve at a later age stage. The importance of the diversity effect may be related reversely to that of species identity in an age gradient of forest stands. The findings suggest that different mechanisms of coexistence operate simultaneously but that their relative importance may shift through the life stages of trees. During the sapling stage, species-specific differences in growth and architectural traits support niche theory. In older forest stands, no species-specific differences in growth parameters could be detected. However, I did find effects of functional diversity on horizontal canopy structure. I conclude that mechanisms of coexistence may not only change with forest stand age, but may also differ for distinct traits. The present thesis, being the first to apply the local neighbourhood approach with regard to crown architecture and branch demography within the BEF field of research, stresses the importance of this individual based approach. Although the observed forest systems are very complex, crown architectural and canopy structural variables were found to be affected by diversity. The finding that the degree of erosive power of rain could be elucidated by crown architectural variables, encourages further studies to reveal possible relations between biodiversity and other ecosystem functions or services, which might be mediated by crown architectural and canopy structural variables.