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Animal pollinators are globally threatened by anthropogenic land use change and agricultural intensification. The yield of many food crops is therefore negatively impacted because they benefit from biotic pollination. This is especially the case in the tropics. For instance, fruit set of Coffea arabica has been shown to increase by 10–30% in plantations with a high richness of bee species, possibly influenced by the availability of surrounding forest habitat. Here, we performed a global literature review to (1) assess how much animal pollination enhances coffee fruit set, and to (2) examine the importance of the amount of forest cover, distance to nearby forest and forest canopy density for bee species richness and coffee fruit set. Using a systematic literature review, we identified eleven case studies with a total of 182 samples where fruit set of C. arabica was assessed. We subsequently gathered forest data for all study sites from satellite imagery. We modelled the effects of open (all forest with a canopy density of ≥25%), closed (≥50%) and dense (≥75%) forests on pollinator richness and fruit set of coffee. Overall, we found that animal pollination increases coffee fruit set by ~18% on average. In only one of the case studies, regression results indicate a positive effect of dense forest on coffee fruit set, which increased with higher forest cover and shorter distance to the forest. Against expectations, forest cover and distance to open forest were not related to bee species richness and fruit set. In summary, we provide strong empirical support for the notion that animal pollinators increase coffee fruit set. Forest proximity had little overall influence on bee richness and coffee fruit set, except when farms were surrounded by dense tropical forests, potentially because these may provide high-quality habitats for bees pollinating coffee. We, therefore, advocate that more research is done to understand the biodiversity value of dense forest for pollinato

In this anthropogenic biodiversity crisis, species are lost at alarming rates. Insects such as wild bees are in sharp declines and further losses are expected in the future. Wild bees engage in complex ecosystem dynamics. Yet, their most prominent function is the pollination of wildflowers and crops. This function is threatened in the wake of their declines. The motivation to halt declines in wild bees and identify responses to the current crisis is the point of departure for this PhD thesis. It aims to increase the understanding of the multitude of ways in which humanity benefits from this ecological group. In addition to measurable values such as crop pollination, wild bees inherent intangible values both for nature and humanity, expressed for instance through cultural and spiritual appreciation. To identify some of these so-called use and non-use values, macroecological and economic valuation techniques are applied in a unique interdisciplinary approach. First, the thesis provides a global assessment of the effects of pollinators on coffee and the role of forest habitat in this process, synergising findings from a number of local studies by use of a systematic literature review and remote sensing (article I). Results confirm the importance of wild bees and other pollinators to crop production systems and indicate that high density forest can support pollinators in these functions. Simultaneously, the study discloses limitations in the use of remote sensing techniques to gain a greater understanding of these processes. Second, the PhD thesis adds to the scarce literature on non-marketed, and particularly non-use values of wild bees and assesses public willingness to engage in wild bee conservation in a stated preference approach in Germany. A choice experiment was used to understand the effect of distance and regional affiliation on respondents’ choices (article II), as well as the valuation of pollination services compared to cultural and non-use values

Social equity is a subject of increasing concern in international debates over protected ar- eas. In 2010, the Convention on Biological Diversity (CBD) adopted 20 Aichi Targets to protect biodiversity and enhance its benefits for people. In Target 11 they stated that at least 17 per cent of terrestrial and inland water areas and 10 per cent of coastal and marine areas should be conserved through “effectively and equitably managed, ecologically representa- tive and well-connected systems of protected areas and other effective area-based conserva- tion measures“. The goal was scheduled to be reached until 2020, but to date no generally adopted methods exist to track progress towards equitable management on a globally com- parable basis. On the contrary, a variety of tools exist to assess protected area management effectiveness (PAME). By means of these tools, a significant amount of data was collected and gathered in the Global Database on Protected Area Management Effectiveness (GD- PAME). This study assesses whether existing PAME tools contain information associated with social equity and if the data can be used to track progress towards the goal in Aichi Target 11 to equitably manage protected areas. A selection of PAME tools and the GD-PAME were re- viewed on equity-related information and case studies were used to test the results in the field. Finally, social and governance assessment tools were evaluated as possible alterna- tives to reach the goal. This study concludes that none of the analysed tools can provide sufficient information to track progress towards equitable management. Neither can the GD-PAME be used, as it contains little accessible information on equity. The findings prompt for a re-thinking of the current approach evaluating complex social dynamics in conservation by scores and rapid assessment methodologies. It is therefore recommended to develop a new tool that aims at truly participatory assessment processes, generates globally compa