@article{RothZoderZamanetal.2020,
  author    = {Roth, Nicolas and Zoder, Sebastian and Zaman, Assad Ali and Thorn, Simon and Schmidl, J{\"u}rgen},
  title     = {Long-term monitoring reveals decreasing water beetle diversity, loss of specialists and community shifts over the past 28 years},
  series = {Insect Conservation and Diversity},
  volume    = {13},
  journal   = {Insect Conservation and Diversity},
  number    = {2},
  doi       = {10.1111/icad.12411},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-214905},
  pages     = {140 -- 150},
  year      = {2020},
  abstract  = {Lentic freshwater organisms are influenced by a multitude of factors, including geomorphology, hydrology, anthropogenic impacts and climate change. Organisms that depend on patchy resources such as water beetles may also be sensitive to anthropogenic habitat degradation, like pollution, eutrophication, water level or management alteration. To assess composition and ecological trends in the water beetle communities of Central Europe, we sampled water beetles (Dytiscidae, Haliplidae, Noteridae) in 33 water bodies in Southern Germany from 1991 to 2018. We used manual, time-standardised capture during three periods: between 1991 and 1995, 2007 and 2008, and 2017 and 2018. During the 28-year survey period, we captured a total of 81 species. We found annual declines in both species number (ca -1\%) and abundance (ca -2\%). Also, community composition showed significant changes over time. The significant impact of pH on the community composition suggests that the recorded changes through time partly reflect natural succession processes. However, a pronounced decline of beetle species belonging to the moor-related beetle associations indicated that Central European water beetles are also threatened by non-successional factors, including desiccation, increased nitrogen input and/or mineralisation, and the loss of specific habitats. This trend to physiographical homogenisation resulted in corresponding community composition shifts. To effectively protect endangered species, conservation strategies need to be aimed at regularly creating new water bodies with mineralic bottom substratum, and maintenance of moor water bodies that represent late successional stages.},
  language  = {en}
}
@article{KortmannRothBuseetal.2022,
  author    = {Kortmann, Mareike and Roth, Nicolas and Buse, J{\"o}rn and Hilszczański, Jacek and Jaworski, Tomasz and Morini{\`e}re, J{\´e}r{\^o}me and Seidl, Rupert and Thorn, Simon and M{\"u}ller, J{\"o}rg C.},
  title     = {Arthropod dark taxa provide new insights into diversity responses to bark beetle infestations},
  series = {Ecological Applications},
  volume    = {32},
  journal   = {Ecological Applications},
  number    = {2},
  doi       = {10.1002/eap.2516},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-276392},
  year      = {2022},
  abstract  = {Natural disturbances are increasing around the globe, also impacting protected areas. Although previous studies have indicated that natural disturbances result in mainly positive effects on biodiversity, these analyses mostly focused on a few well established taxonomic groups, and thus uncertainty remains regarding the comprehensive impact of natural disturbances on biodiversity. Using Malaise traps and meta-barcoding, we studied a broad range of arthropod taxa, including dark and cryptic taxa, along a gradient of bark beetle disturbance severities in five European national parks. We identified order-level community thresholds of disturbance severity and classified barcode index numbers (BINs; a cluster system for DNA sequences, where each cluster corresponds to a species) as negative or positive disturbance indicators. Negative indicator BINs decreased above thresholds of low to medium disturbance severity (20\%-30\% of trees killed), whereas positive indicator BINs benefited from high disturbance severity (76\%-98\%). BINs allocated to a species name contained nearly as many positive as negative disturbance indicators, but dark and cryptic taxa, particularly Diptera and Hymenoptera in our data, contained higher numbers of negative disturbance indicator BINs. Analyses of changes in the richness of BINs showed variable responses of arthropods to disturbance severity at lower taxonomic levels, whereas no significant signal was detected at the order level due to the compensatory responses of the underlying taxa. We conclude that the analyses of dark taxa can offer new insights into biodiversity responses to disturbances. Our results suggest considerable potential for forest management to foster arthropod diversity, for example by maintaining both closed-canopy forests (>70\% cover) and open forests (<30\% cover) on the landscape.},
  language  = {en}
}