Evaluating Biodiversity Metrics for Detecting Climate-Driven Ecological Change Attila Haris, Zsolt Józan, Attila Balázs, George Japoshvili, György Csóka, et al. Ecologies, 2026 To investigate the long-term effects of climate change on biological communities, our primary aim was to identify the most reliable indicators among available biodiversity, dominance, and evenness indices. We examined three distinct response types to climate change, represented by three taxonomic groups: Aculeata (Hymenoptera), Syrphidae (Diptera), and nocturnal macrolepidoptera (Lepidoptera). Using faunistic datasets derived from our own 3–5 decades of field surveys, we calculated 12 key indices with the vegan package in R 4.2.1. The robustness of these indices was assessed through 1000-fold bootstrap simulations and pairwise correlation analyses. Our results revealed that the Gini–Simpson, Simpson diversity, McIntosh diversity, and McIntosh evenness indices consistently demonstrated high temporal stability and strong correlations across all three climate response types. Therefore, we recommend these indices as primary climate indicators. In contrast, Chao1 estimates, Margalef Index, Menhinick Index, and the Shannon–Wiener diversity index are suitable only for analyzing specific response patterns. Meanwhile, the Berger–Parker, Buzas–Gibson indices, and Hill numbers showed high variability or limited ecological responsiveness, making them unreliable for tracking climate change impacts. Our findings underscore that selecting biodiversity indices must be tailored to the research question and the characteristics of the ecosystem in order to ensure valid and informative ecological analysis.
Trait-based explanation of circadian flight rhythms in bark and ambrosia beetles (Scolytinae) Dominik Stočes, Jan Šipoš, Attila Balázs, Jiří Procházka, David Kopr, et al. Bulletin of Entomological Research, 2025 Understanding the circadian rhythms of bark and ambrosia beetles (Scolytinae) is crucial for assessing their dispersal strategies, trophic specialisation, and microhabitat preferences. This study investigated circadian rhythms in Scolytinae communities using flight interception traps in an oak forest in the southern part of Czechia. Ordination biplot revealed a flight activity gradient, with nocturnal dispersers distinct from diurnal species. Species richness gradually decreased from the 20:00–24:00 interval through to the 12:00–16:00 interval, with the most notable decline observed between the 08:00–12:00 and 12:00–16:00 intervals. A combination of fourth-corner and partial canonical correspondence analyses identified tribal affiliation, trophic specialisation, and microhabitat preference as key drivers of flight structuring. Members of the tribe Xyleborini showed negative association to the 16:00–20:00 interval. Xylomycetophagous species, such as Xyleborinus saxesenii exhibited multimodal activity peaks, with increased flight from nighttime to early morning. In contrast, species that feed in the phloem such as Scolytus intricatus showed no significant association with any specific time interval. Several species that utilise stumps as potential breeding substrates showed significantly reduced flight activity during the crepuscular period, which supports the hypothesis that microhabitat preference contributes to diel periodicity. Our findings show the complex interplay between abiotic and biotic factors in shaping circadian flight periodicity, which leads to distinct flight activity patterns between Scolytini bark and Xyleborini ambrosia beetles. These results emphasise the ecological significance of maintaining heterogeneous forest structures that provide a balance of shaded and sun-exposed deadwood habitats to support diverse assemblages.
Beetle assemblage distribution along edge–forest gradient in a managed oak forest Attila Balázs, Jan Bezděk, Jan Šipoš Agricultural and Forest Entomology, 2024 Forest management practices creating small‐scale forest edge habitats in managed forests have substantial impacts on the formation of beetle assemblages. In 2021, we conducted research in a managed oak woodland in Central Slovakia using three flight interception traps (FITs) to study beetle assemblages. Two FITs were installed at the forest edge, facing both, the clearing and the closed‐stand forest, while the third FIT was positioned 100 m within the closed‐canopy forest. We employed a novel methodological approach, which involved separately collected subsamples within the ecotone using FITs differentiated as ‘ecotone inwards’ and ‘ecotone outwards’ to capture distinct directional movements at the edge. We recorded 5.997 beetle specimens, encompassing 417 species across 284 genera and 58 families. We found that the species diversity and abundance of beetles were not significantly different between the FITs. However, the species composition was significantly different. The partial detrended canonical correspondence analysis suggests that these compositional differences might be closely associated with the distribution of trophic guilds, indicating varied responses to habitat modifications induced by forest edge creation. The results of our study showed that phloephagous, saproxylophagous, xylomycetophagous, xylophagous and zoophagous beetles exhibited a positive association with the forest edge, while mycophagous, phytophagous and saprophagous groups were distinctly associated with the closed‐canopy forest. Our analyses indicated that the ‘ecotone outward’ part of forest edges of managed forest may attract higher number of trophic groups, while the ‘ecotone inward’ part of the forest edge hosted high abundances of phloephagous and xylomycetophagous species.
Is the Current Forest Management to the Northernmost Population of Cordulegaster heros (Anisoptera: Cordulegastridae) in Central Europe (Czech Republic) Threatening? Otakar Holuša, Kateřina Holušová, Attila Balázs Forests, 2023 Cordulegaster heros is included in the EN category on the IUCN Red List for the territory of the Czech Republic, where it inhabits an area of approximately 100 km2. All of the localities are located in the forest complex in Chřiby hills, and all of the forests fall into the category of management forests. Most of the forest stands have a high and very high degree of naturalness; they are natural forest stands. The predominant management units are Nutrient sites in middle elevations (78.2% of the area) and Oligotrophic sites in middle elevations (2.1% of the area), with stand types of Fagus sylvatica representing 92.5% of the area, and forest stand types of Quercus sp. representing 5.7% of the area. The wider alluvia in forest streams are classified as being in management unit alder and ash sites on waterlogged and floodplain soils (1.1%), with the forest stand type of Alnus glutinosa. The forest stands are restored by regeneration under shelterwood (97.8% of the area). The waterlogged alluvia, if a separate management unit is established for them, are restored by a regeneration by strip method. Realistically, seven factors were recorded in C. heros habitats, but they mostly have only point effects. Within forestry management, the factors of logging directly in the habitats and the subsequent transport of harvested timber in the habitat were recorded. The most intrusive effects were found on tractor logging roads, where fine soil washes into the stream and causes prolonged turbidity. Of the water management structures in the study area, logging roads with bridges and culverts are constructed, stream banks are reinforced with longitudinal walls at points, and stone steps in the channels are constructed only sporadically. The current forest management system can be described as a nature-friendly system, and therefore, it fully ensures the conditions for the survival of the C. heros population in the Czech Republic.
Flying activity and population dynamics of Cordulegaster heros Theischinger, 1979 (Insecta: Odonata: Cordulegastridae) in Slovakia Attila Balázs, Zdeněk F. Fric, Otakar Holuša International Journal of Odonatology, 2020 In 2017, we investigated the population dynamics and flying activity of the south-east European endemic dragonfly species Cordulegaster heros Theischinger, 1979. This research was conducted in the southern part of Central Slovakia in the Revúcka vrchovina Upland at a submountainous stream called Drienok. The mark-release-recapture method was applied to study the population. Cordulegaster heros was observed 775 times during the midsummer season. We found out that the species has bimodal diurnal activity pattern with a highest peak from 17:00 until 19:00 hours, but the species had a short peak before noon as well. The differences between sexes in the sense of entering new individuals to the population were low during the main flying period. Estimated population size for males surpassed the population size of females. Probability of capture decreased by the end of the flying season without differences in sexes. This article is the first on the flying activity and population dynamics of Cordulegaster heros.
