@phdthesis{Lehenberger2022,
  author    = {Lehenberger, Maximilian},
  title     = {Ecology and Evolution of symbiotic microbial communities in fungus farming ambrosia beetles},
  publisher = {Fungal Ecology, Frontiers in Microbiology, Deutsche Gesellschaft f{\"u}r allgemeine und angewandte Entomologie},
  doi       = {10.25972/OPUS-24154},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-241546},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2022},
  abstract  = {Within my PhD project I gained several novel insights into the poorly investigated symbiotic world of fungus farming ambrosia beetles and their bark beetle ancestors, where I especially focused on physiological interactions and capabilities of associated fungal symbionts. Here, (i) I could confirm the association of mutualistic Phialophoropsis fungi with the ambrosia beetle genus Trypodendron and found hints for a possible new Phialophoropsis species in T. signatum and T. domesticum. Moreover, I could show that mutualistic fungi of Trypodendron ambrosia beetles are able to decompose major woody polysaccharides such as cellulose and xylan. Additionally, (ii) I provided the first images using micro-computed tomography (µCT) of the formerly unknown structure of the mycetangium of Trypodendron leave. (iii) I could confirm a general tolerance towards ethanol in mutualistic ambrosia beetle fungi, while antagonistic fungi as well as most examined fungal bark beetle associates (e.g. possibly tree-defense detoxifying species) were highly sensitive to even low concentrations of ethanol. Further, (iv) I found that natural galleries of ambrosia beetles are highly enriched with several biologically important elements (such as N, P, S, K, Mg) compared to the surrounding woody tissue and suggest that mutualistic fungi are translocating and concentrating elements from the immediate surrounding xylem to the beetles galleries. Furthermore, (v) I could show that various fungi associated with bark and ambrosia beetles (mutualists, possibly beneficial symbionts) are emitting several volatile organic compounds mostly within aliphatic and aromatic alcohols and esters, while non-mutualistic and free living species were generally emitting a lower number and amount of volatiles. Finally, especially bark and ambrosia beetle fungi were found to incorporate several amino acids, from which some are especially important for the production of certain volatile organic compounds. Amino acid content also indicated a higher nutritional value for certain species. Here, I propose that especially volatile organic compounds are widespread key players in maintaining various symbioses between fungi and beetles, as already proven by a recent study on the bark beetle Ips typographus (as well as for some other bark beetle-fungus symbioses, see summary in Kandasamy et al. 2016) and also suggested for ambrosia beetles.},
  language  = {en}
}
@phdthesis{Kortmann2022,
  author    = {Kortmann, Mareike},
  title     = {Biodiversity and recreation - Optimizing tourism and forest management in forests affected by bark beetles},
  doi       = {10.25972/OPUS-24031},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-240317},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2022},
  abstract  = {Forests are multi-functional system, which have to fulfil different objectives at the same time. The main functions include the production of wood, storage of carbon, the promotion of biological diversity and the provision of recreational space. Yet, global forests are affected by large and intense natural disturbances, like bark beetle infestations. While natural disturbances threaten wood production and are perceived as 'catastrophe' diminishing recreational value, biodiversity can benefit from the disturbance-induced changes in forest structures. This trade-off poses a dilemma to managers of bark beetle affected stands, particularly in protected areas designated to both nature conservation and recreation. Forest landscapes need a sustainable management concept aligning these different objectives. In order to support this goal with scientific knowledge, the aim of this work is to analyse ecological and social effects along a gradient of different disturbance severities. In this context, I studied the effects of a disturbance severity gradient on the diversity of different taxonomic groups including vascular plants, mosses, lichens, fungi, arthropods and birds in five national parks in Central Europe. To analyse the recreational value of the landscape I conducted visitor surveys in the same study areas in which the biodiversity surveys were performed. To analyse possible psychological or demographic effects on preferences for certain disturbance intensities, an additional online survey was carried out.},
  subject      = {Borkenk{\"a}fer},
  language  = {en}
}