Small-scale spontaneous dynamics in temperate beech stands as an importance driver for beetle species richness

Abstract

Natural dynamics in forests play an important role in the lives of many species. In the landscape of managed forests, natural disturbances are reduced by management activities. This usually has a significant effect on insect diversity. The effect of small-scale natural dynamics of protected beech stands on the richness of saproxylic and non-saproxylic beetles was investigated. Sampling was carried out by using flight interception traps in the framework of comparing different developmental stages: optimum, disintegration, and growing up, each utilizing 10 samples. We recorded 290 species in total, of which 61% were saproxylic. The results showed that the highest species richness and thus abundance was in the disintegration stage. In each developmental stage, species variation was explained differently depending on the variable. Deadwood, microhabitats, and canopy openness were the main attributes in the later stages of development for saproxylic beetles. For non-saproxylics, variability was mostly explained by plant cover and canopy openness. Small-scale disturbances, undiminished by management activities, are an important element for biodiversity. They create more structurally diverse stands with a high supply of feeding and living habitats. In forestry practice, these conclusions can be imitated to the creation of small-scale silvicultural systems with active creation or retention of high stumps or lying logs.

Trapping liquids may bias the results of beetle diversity assessment

“…The other methods of collecting entomological material are more suitable for collecting purposes and to observe life history, bionomy and phenology. Window traps are mostly used to assess the biodiversity of saproxylic beetles ( Zumr, Remeš & Nakládal, 2022 ; Rothacher et al, 2023 ). Pitfall traps are used to assess different epigeic groups, especially beetles ( Elek, Magura & Tóthmérész, 2001 ; Sroka & Finch, 2006 ; Podrázský, Remeš & Farkač, 2010 ) or spiders and ants ( Černecká et al, 2020 ; Montgomery et al, 2021 ).…”