The Impact of Edge Effects & Matrix Restoration on Dung Beetle Community Structure & Ecosystem Function

Land-use change has become a force of global importance and has gained status as the most important driver of ecosystem degradation. The resulting creation of habitat edges has pervasive impacts on the distribution and persistence of species in forest ecosystems. Responses of species to edge effects can be highly dependent on ‘response’ traits, which may in turn co-vary with ‘effect’ traits that determine rates of ecosystem functioning. Therefore, non-random loss of species due to traits conferring higher susceptibility to extinction may also result in the loss of functionally-important species across a habitat edge gradient. Likewise, response and effect traits may be important in determining reassembly of communities in regenerating habitats, which may provide insight into potential scenarios of functional responses to restoration efforts. To test for potential off-site effects of adjacent matrix habitat restoration on dung beetle communities, I compared dung beetle community structure and species trait composition across Afromontane forest edges adjacent to degraded and regenerating matrix habitat at Ngel Nyaki forest reserve in Nigeria. I also measured dung removal rates across habitat edge gradients to investigate the relative off-site impacts of matrix restoration on dung beetle-mediated ecosystem processes. I found significant effects of adjacent matrix condition on edge response functions in dung beetle abundance, species distributions, and trait composition. Beetle abundances were markedly higher in forests adjacent to regenerating matrix, whereas the largest differences in trait composition were found between degraded and regenerating matrix habitat, indicating the presence of ecological filtering processes in these areas. Furthermore, I found that species traits determined community structural responses to environmental change and this had strong flow-on effects to rates of dung removal. Shifts in trait distributions explained dung removal rates above and beyond total beetle mass, suggesting that neutral processes alone could not explain functional efficiency. In particular, habitat regeneration resulted in the assembly of communities with high total beetle mass and on-average smaller beetles, which was optimal for functional efficiency. In conclusion, the restoration of adjacent matrix habitat was shown to effectively mitigate edge effects on dung beetle community structure resulting in the re-establishment of important associated ecosystem processes

Informatische Methoden zur Unterstützung von Transkription, Lokalisierung und Adressierung in kulturwissenschaftlichen Communities

The success of community information systems depends on a careful design of the digital media, and on the related tools for communication and collaboration. Particularly for the cultural sciences the community engine should be capable of supporting the discursive processes of hypermedia knowledge management and sharing. Information systems therefore need to reflect the underlying community processes through well adapted media sets of drawings, animations, pictures, digital video, text etc. The information system architecture ATLAS (Architecture for Transcription, Localization, and Addressing Systems) is based on a formalization of an operational media-theory and knowledge management theory for information systems. My work introduces the Lightweight Application Server (LAS), which is an infrastructure to support this formalization. LAS offers dedicated multimedia services for media centric work in communities on the basis of the multimedia content description interface MPEG-7. Besides its advanced multimedia support LAS offers extending and reloading of services at runtime, as well a role-based security concept. The introduced theory and the LAS have been evaluated in different information systems for cultural science communities in research and education