Měkkýši přírodních památek Kalábová a Kalábová 2 v CHKO Bílé Karpaty [Molluscs of the Kalábová and Kalábová 2 Nature Monuments in the White Carpathians PLA]

The Kalábová (K1) and Kalábová 2 (K2) Nature Monuments are located in the central part of the White Carpathians PLA near the village of Březová. Both monuments protect treeless wet grasslands and tufa forming spring fens, which were originally part of a larger wetland complex. A total of 51 species were recorded in K1 (47 terrestrial and two aquatic gastropods and two bivalves). Of these, 30 species (56%) are woodland dwellers that were recorded during the survey in 2000, shortly after the area was logged. In contrast, none of these species was detected during the recent survey in 2021. However, these species are widespread in the region and Nature Monuments surroundings and some are likely present also in the ecotones of the spring meadow and adjacent forest. Currently, hygrophilous and wetland dwellers dominate (9 spp.; 17%), followed by ubiquitous (7; 15%), open-ground (4; 8%) and aquatic species (4; 8%). At K2, 19 species were recorded, including 15 terrestrial and two aquatic gastropods, and two bivalves. The two most species-rich ecogroups were hygrophilous and wetland dwellers (5; 26%) and woodland dwellers (5; 26%), the latter were prevailing probably due to relatively recent deforestation between 2012–2014. Aquatic species were represented by four species (21%), followed by three ubiquitous (16%) and one open-ground (5%) species. The spring dweller Bythinella austriaca (NT) and the declining wetland umbrella species Vertigo angustior (VU; NATURA 2000) inhabited both localities in high densities. To maintain the favourable habitat conservation status of the reserves, the sites should be managed extensively by grazing or mowing.

Měkkýši přírodní rezervace Hutě a jejího okolí v CHKO Bílé Karpaty [Molluscs of the Hutě Nature Reserve and its surroundings in the White Carpathians PLA]

The Hutě Nature Reserve is located in the central eastern part of the White Carpathians PLA, near the Žítková village. The reserve protects a preserved and topographically heterogeneous area composed of forest groves, meadows, pastures, and spring fens with a high diversity of submontane and thermophilic plant and animal assemblages. The species composition of molluscs (9 out of 10 ecological groups represented) consists mainly of woodland dwellers, which account for the majority of species diversity (30 spp.; 52%), followed by ubiquitous (9; 16%), hygrophilous (5; 9%), hygrophilous woodland dwellers (4; 7%), aquatic (4; 7%) and open-habitat dwellers (3; 5%). Vertigo moulinsiana (EN), internationally protected under Annex II of the EU Habitats Directive, Daudebardia brevipes (VU), Ambigolimax nyctelius (NT), Orcula dolium (NT) and Bythinella austriaca (NT) are species of conservation concern. To retain favourable habitat conservation status, the spring fens with V. moulinsiana occurrence must be managed extensively by grazing or mowing, while the forests must remain in a non-intervention regime.

Community metabarcoding uncovers vast diversity and a lack of barcode references for aquatic invertebrates in Carpathian spring fens

Recent studies on diversity of stream amphipods proposed that the Western Carpathians have served as an important glacial refugium of freshwater fauna. If this scenario is true, a considerably high molecular diversity can be expected in this biogeographic region also for other taxa. In our project, we aimed to uncover and characterize molecular diversity of benthic macroinvertebrate fauna of spring fens, a well studied and hence convenient model community. Using a DNA metabarcoding approach, we sequenced a fragment of the COI gene of pooled spring fen invertebrate communities from 21 localities in the Western Carpathians. The preliminary analysis of the sequences revealed a substantially higher amount of operational taxonomic units (OTUs), when compared to the number of taxa identified in the same spring fens based on morphological characters. The lack of reference sequences in public databases (Barcoding of Life Database, GenBank) for the majority of the detected OTUs indicates that the Western Carpathian region is not yet sufficiently covered by barcoding efforts, and suggests that there indeed may be a considerable unrecognized diversity of macrozoobenthos. However, most newly uncovered diversity is concentrated in a few taxa such as the dipteran families Tabanidae and Ceratopogonidae, annelid species (complexes) Eiseniella tetraedra and Helobdella stagnalis or the amphipod genus Gammarus. In the future, these findings will be the basis for several levels of research: detailed investigation of seemingly hyperdiverse taxa (phylogeography, phylogeny, reference coverage) and comparison of overall molecular diversity of these communities in the Western Carpathians and neighbouring Bohemian Massif, a region where we expect much lower diversity due to different biogeographic history.

The Chironomidae of the Western Carpathian helocrenes: Metacommunity structuring and its drivers in unique habitats

Springs are unique and vulnerable habitats, which have always been rather out of focus of the scientist interest. Nevertheless, they frequently host very diverse and species-rich assemblages with high proportion of species more or less adapted to their unique environment and can act as biodiversity hotspots in some areas. The Western Carpathian springs are helocrene springs and represent wide variety of different habitat types, from mineral rich sparsely-vegetated or bryophytes-rich covered helocrenes to acidic peaty sites. Such diversification allows the creation of highly diverse assemblages, in which Chironomidae usually dominate in both species richness and abundance. The aim of this study was to provide a comprehensive overview of chironomid assemblages inhabiting the unique environment of spring fens and factors driving the metacommunity structuring and populations of individual taxa. We examined chironomid assemblages of 62 small, treeless helocrenes sites, which are highly isolated from each other by the terrestrial environment constituting dispersal barriers such as the east-west oriented mountain ridges and valleys. The sampling was performed to cover mesohabitat heterogeneity of study sites. Two main mesohabitats were sampled, the plot with flowing water and coarser substratum near water source (the lotic mesohabitat), and water-logged soil with standing water (the lentic mesohabitat). Study sites hosted nearly 100 chironomid taxa, both mesohabitats were inhabited by chironomid assemblages similar in number of species and abundances and the local environment was proved to be the main driver of compositional changes in chironomid assemblages as expected. Moreover, the significant spatial structure of assemblages was found at the lentic mesohabitat, while biotic interactions described by the abundance of Gammarus fossarum and taxa richness and abundances of predators did not significantly contribute to compositional changes in assemblages at any mesohabitat. Nevertheless, taxa-specific responses revealed populations of many taxa significantly affected by biotic interactions, especially at the more stable lotic mesohabitat, which is in concordance with suggested greater importance of biotic interactions at stable environment. Our results emphasized the importance of multilevel approach in community ecology for proper distinction between different mechanisms of metacommunity structuring. Biotic interaction such as competition can result into the same community patterns as environmental filtering, thus the involvement of detailed analyses of species requirements and interactions is necessary.