@article{VogelBusslerFinnbergetal.2021, author = {Vogel, Sebastian and Bussler, Heinz and Finnberg, Sven and M{\"u}ller, J{\"o}rg and Stengel, Elisa and Thorn, Simon}, title = {Diversity and conservation of saproxylic beetles in 42 European tree species: an experimental approach using early successional stages of branches}, series = {Insect Conservation and Diversity}, volume = {14}, journal = {Insect Conservation and Diversity}, number = {1}, doi = {10.1111/icad.12442}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-218401}, pages = {132 -- 143}, year = {2021}, abstract = {Tree species diversity is important to maintain saproxylic beetle diversity in managed forests. Yet, knowledge about the conservational importance of single tree species and implications for forest management and conservation practices are lacking. We exposed freshly cut branch-bundles of 42 tree species, representing tree species native and non-native to Europe, under sun-exposed and shaded conditions for 1 year. Afterwards, communities of saproxylic beetles were reared ex situ for 2 years. We tested for the impact of tree species and sun exposure on alpha-, beta-, and gamma-diversity as well as composition of saproxylic beetle communities. Furthermore, the number of colonised tree species by each saproxylic beetle species was determined. Tree species had a lower impact on saproxylic beetle communities compared to sun exposure. The diversity of saproxylic beetles varied strongly among tree species, with highest alpha- and gamma-diversity found in Quercus petraea. Red-listed saproxylic beetle species occurred ubiquitously among tree species. We found distinct differences in the community composition of broadleaved and coniferous tree species, native and non-native tree species as well as sun-exposed and shaded deadwood. Our study enhances the understanding of the importance of previously understudied and non-native tree species for the diversity of saproxylic beetles. To improve conservation practices for saproxylic beetles and especially red-listed species, we suggest a stronger incorporation of tree species diversity and sun exposure of into forest management strategies, including the enrichment of deadwood from native and with a specific focus on locally rare or silviculturally less important tree species.}, language = {en} } @article{VogelGossnerMergneretal.2020, author = {Vogel, Sebastian and Gossner, Martin M. and Mergner, Ulrich and M{\"u}ller, J{\"o}rg and Thorn, Simon}, title = {Optimizing enrichment of deadwood for biodiversity by varying sun exposure and tree species: An experimental approach}, series = {Journal of Applied Ecology}, volume = {57}, journal = {Journal of Applied Ecology}, number = {10}, doi = {10.1111/1365-2664.13648}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-214614}, pages = {2075 -- 2085}, year = {2020}, abstract = {The enrichment of deadwood is essential for the conservation of saproxylic biodiversity in managed forests. However, existing strategies focus on a cost-intensive increase of deadwood amount, while largely neglecting increasing deadwood diversity. Deadwood objects, that is logs and branches, from six tree species were experimentally sun exposed, canopy shaded and artificially shaded for 4 years, after which the alpha-, beta- and gamma-diversity of saproxylic beetles, wood-inhabiting fungi and spiders were analysed. Analyses of beta-diversity included the spatial distance between exposed deadwood objects. A random-drawing procedure was used to identify the combination of tree species and sun exposure that yielded the highest gamma-diversity at a minimum of exposed deadwood amount. In sun-exposed plots, species numbers in logs were higher than in shaded plots for all taxa, while in branches we observed the opposite for saproxylic beetles. Tree species affected the species numbers only of saproxylic beetles and wood-inhabiting fungi. The beta-diversity of saproxylic beetles and wood-inhabiting fungi among logs was influenced by sun exposure and tree species, but beta-diversity of spiders by sun exposure only. For all saproxylic taxa recorded in logs, differences between communities increased with increasing spatial distance. A combination of canopy-shaded Carpinus logs and sun-exposed Populus logs resulted in the highest species numbers of all investigated saproxylic taxa among all possible combinations of tree species and sun-exposure treatments. Synthesis and applications. We recommend incorporating the enrichment of different tree species and particularly the variation in sun exposure into existing strategies of deadwood enrichment. Based on the results of our study, we suggest to combine the logs of softwood broadleaf tree species (e.g. Carpinus, Populus), hardwood broadleaf tree species (e.g. Quercus) and coniferous tree species (e.g. Pinus) under different conditions of sun exposure and distribute them spatially in a landscape to maximize the beneficial effects on overall diversity.}, language = {en} } @article{VogelPrinzingBussleretal.2021, author = {Vogel, Sebastian and Prinzing, Andreas and Bußler, Heinz and M{\"u}ller, J{\"o}rg and Schmidt, Stefan and Thorn, Simon}, title = {Abundance, not diversity, of host beetle communities determines abundance and diversity of parasitoids in deadwood}, series = {Ecology and Evolution}, volume = {11}, journal = {Ecology and Evolution}, number = {11}, doi = {10.1002/ece3.7535}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-238892}, pages = {6881 -- 6888}, year = {2021}, abstract = {Most parasites and parasitoids are adapted to overcome defense mechanisms of their specific hosts and hence colonize a narrow range of host species. Accordingly, an increase in host functional or phylogenetic dissimilarity is expected to increase the species diversity of parasitoids. However, the local diversity of parasitoids may be driven by the accessibility and detectability of hosts, both increasing with increasing host abundance. Yet, the relative importance of these two mechanisms remains unclear. We parallelly reared communities of saproxylic beetle as potential hosts and associated parasitoid Hymenoptera from experimentally felled trees. The dissimilarity of beetle communities was inferred from distances in seven functional traits and from their evolutionary ancestry. We tested the effect of host abundance, species richness, functional, and phylogenetic dissimilarities on the abundance, species richness, and Shannon diversity of parasitoids. Our results showed an increase of abundance, species richness, and Shannon diversity of parasitoids with increasing beetle abundance. Additionally, abundance of parasitoids increased with increasing species richness of beetles. However, functional and phylogenetic dissimilarity showed no effect on the diversity of parasitoids. Our results suggest that the local diversity of parasitoids, of ephemeral and hidden resources like saproxylic beetles, is highest when resources are abundant and thereby detectable and accessible. Hence, in some cases, resources do not need to be diverse to promote parasitoid diversity.}, language = {en} } @article{ZielewskaBuettnerHeurichMuelleretal.2018, author = {Zielewska-B{\"u}ttner, Katarzyna and Heurich, Marco and M{\"u}ller, J{\"o}rg and Braunisch, Veronika}, title = {Remotely Sensed Single Tree Data Enable the Determination of Habitat Thresholds for the Three-Toed Woodpecker (Picoides tridactylus)}, series = {Remote Sensing}, volume = {10}, journal = {Remote Sensing}, number = {12}, issn = {2072-4292}, doi = {10.3390/rs10121972}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-197565}, year = {2018}, abstract = {Forest biodiversity conservation requires precise, area-wide information on the abundance and distribution of key habitat structures at multiple spatial scales. We combined airborne laser scanning (ALS) data with color-infrared (CIR) aerial imagery for identifying individual tree characteristics and quantifying multi-scale habitat requirements using the example of the three-toed woodpecker (Picoides tridactylus) (TTW) in the Bavarian Forest National Park (Germany). This bird, a keystone species of boreal and mountainous forests, is highly reliant on bark beetles dwelling in dead or dying trees. While previous studies showed a positive relationship between the TTW presence and the amount of deadwood as a limiting resource, we hypothesized a unimodal response with a negative effect of very high deadwood amounts and tested for effects of substrate quality. Based on 104 woodpecker presence or absence locations, habitat selection was modelled at four spatial scales reflecting different woodpecker home range sizes. The abundance of standing dead trees was the most important predictor, with an increase in the probability of TTW occurrence up to a threshold of 44-50 dead trees per hectare, followed by a decrease in the probability of occurrence. A positive relationship with the deadwood crown size indicated the importance of fresh deadwood. Remote sensing data allowed both an area-wide prediction of species occurrence and the derivation of ecological threshold values for deadwood quality and quantity for more informed conservation management.}, language = {en} }