This article presents the first attempt to date moraines in the Dinaric mountain karst using cosmogenic 36Cl surface exposure dating technique. Twenty samples were collected from moraine boulders ...from two sets of the lowest and largest lateral moraines on the Velež (1965 m asl) and Crvanj mountains (1920 m asl) in Bosnia and Herzegovina. The dated lateral-terminal moraine complexes, spanning elevations from ∼980 to 1350 m asl, are up to 2.7 km long and rise more than 100 m above the valley floor. The moraine boulders yielded 36Cl ages spanning from Oldest Dryas for Velež (14.9 ± 1.1 ka) to Younger Dryas for Crvanj (11.9 ± 0.9 ka), considering the average age of the two oldest samples from each lateral moraine as the most representative time of moraine emplacement. The dated moraines mark the largest extent of glaciers in both study areas, which have been reconstructed to ∼28 km2 for Velež and ∼24 km2 for Crvanj, having a mean equilibrium line altitude at 1388 m and 1541 m, respectively. Under modern precipitation values, which account for ∼2000 mm, the temperature depression between 8 and 10 °C is required to sustain the palaeoglaciers with reconstructed equilibrium line altitudes. Glaciers of similar size with such low equilibrium line altitudes during the Lateglacial have not been reported until now for the Balkan Peninsula. It is very likely that the boulder ages reflect complex exhumation and denudation histories, which at this point do not allow obtaining more precise moraine chronologies for the study areas. Nevertheless, this article delivers new data on the extent and timing of Quaternary glaciations in the Mediterranean mountains, where records of glacier fluctuations seem to be asynchronous amongst different areas. It is clear that dating moraines with cosmogenic 36Cl surface exposure dating in carbonate lithologies in areas of high precipitation like the Dinaric karst, remains challenging.
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•The largest extent of palaeoglaciers was reconstructed.•20 moraine boulders from two sets of lateral moraines were dated.•The boulders yielded 36Cl ages of 14.9 ± 1.1 ka for Velež and 11.9 ± 0.9 ka for Crvanj.•Boulder ages reflect complex exhumation and denudation histories.•Dating moraines with cosmogenic 36Cl nuclide dating in the Dinaric karst remains challenging.
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•Removal of invasive plant species resulted in reactivation of dry streams.•The resulting periphyton structure reflected environmental changes.•Ciliates and testate amoebas dominated ...the new communities.•High organic matter content did not impede tufa deposition.
The formation of tufa barriers is driven by specific physicochemical and biological factors which make them very sensitive to environmental changes. The barriers provide great microhabitat complexity and are therefore inhabited by various periphytic organisms, whose metabolic activity alters the microenvironment, directly or indirectly affecting the physicochemical conditions of calcite precipitation. After the invasive plant species Ailanthus altissima (Mill.) Swinge was identified as one of the main factors causing current dryness of streams at the Skradinski buk barrier (Krka National Park, Croatia), the invasive species was removed, resulting in changes in the hydromorphology of the barrier and reactivating previously dry streams. The objective of this study was to determine potential differences between control and revitalized sites (reactivated streams) with regards to periphyton and the associated environmental changes over an annual cycle. Clear patterns were observed between sites reflecting the substantial changes in the landscape following invasive species removal. Revitalized sites had lower flow velocity, conductivity, pH, alkalinity and total water hardness values while exhibiting higher values of dissolved organic matter, nitrites and orthophosphates due to the presence of soil-derived organic material and intensive soil drainage. Organic matter content was generally higher at revitalized sites but did not inhibit tufa deposition. The influence of the surrounding forest soil was reflected not only in the mineralogical analysis of tufa sediment, but also in the abundance and diversity of periphyton. Revitalized site communities exhibited higher abundance and diversity and were dominated by bacterivorous and omnivorous ciliates and cercozoans due to the abundant food resources of the soil. The results presented show that ecosystem responses to hydromorphological changes generated by invasive species removal can be efficiently detected and monitored at microscale (i.e., periphyton scale) through a comprehensive interdisciplinary approach. As the first study to examine the relationship between aquatic ecosystems and sediments in the context of tufa stream revitalization, this pilot study provides data and guidelines for future management plans applicable to various tufa depositing systems facing invasive species propagation, allowing better understanding and protection of this unique and vulnerable karstic feature.
In the present study morphological and molecular data from specimens of the troglobitic genus Speoplanes have been examined. The two subspecies Speoplanes giganteus giganteus Müller, 1911 and ...Speoplanes giganteus biocovensis Müller, 1934 are changed in rank from subspecies to species level and discrete identification characters for the separation of the two species are provided. Additionally, all known localities of the species (including new records) are listed and a distribution map of the genus is provided.
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•First regional investigation of EOCs in Dinaric karst aquifers.•65 different EOCs detected, conc. <1 ng/L for almost half.•EOC concentrations are two orders of magnitude lower than ...in other groundwater types.•EOCs are detected more frequently than in other types of groundwater.•EOCs are detected in greater or comparable numbers than in other groundwater types.
Emerging organic contaminants (EOCs) have become of increasing interest due to concerns about their impact on humans and the wider environment. Karst aquifers are globally widespread, providing critical water supplies and sustaining rivers and ecosystems, and are particularly susceptible to pollution. However, EOC distributions in karst remain quite poorly understood. This study looks at the occurrence of EOCs in the Croatian karst, which is an example of the “classical” karst, a highly developed type of karst that occurs throughout the Dinaric region of Europe. Samples were collected from 17 karst springs and one karst lake used for water supply in Croatia during two sampling campaigns. From a screen of 740 compounds, a total of 65 compounds were detected. EOC compounds from the pharmaceutical (n = 26) and agrochemical groups (n = 26) were the most frequently detected, while industrials and artificial sweeteners had the highest concentrations (range 8–440 ng/L). The number of detected compounds and the frequency of detection demonstrate the vulnerability of karst to EOC pollution. Concentrations of 5 compounds (acesulfame, sucralose, perfluorobutane sulfonate, emamectin B1b, and triphenyl phosphate) exceeded EU standards and occurred at concentrations that are likely to be harmful to ecosystems. Overall, most detections were at low concentrations (50 % <1 ng/L). This may be due to high dilution within the exceptionally large springs of the Classical karst, or due to relatively few pollution sources within the catchments. Nevertheless, EOC fluxes are considerable (10 to 106 ng/s) due to the high discharge of the springs. Temporal differences were observed, but without a clear pattern, reflecting the highly variable nature of karst springs that occurs over both seasonal and short-term timescales. This research is one of a handful of regional EOC investigations in karst groundwater, and the first regional study in the Dinaric karst. It demonstrates the need for more frequent and extensive sampling of EOCs in karst to protect human health and the environment.
•Clay-rich soils on limestones from the Dinaric Karst region are classified as Luvisols.•Illuvial processes explain differences in the geochemical and mineral composition of horizons.•Allochthonous ...contributions from different sources influence the formation of Luvisols.•Pedogenesis prevails over heterogeneity of profile sites and contribution of allochthonous material.•Well-developed soil horizons indicate intense pedogenetic processes.
In environments with high precipitation, eluvial–illuvial processes play a key role in pedogenesis. Vertical translocation of clay leads to the formation of an argic horizon. Such soils are of global importance and formed on different rock substrates under different climatic conditions. However, the pedogenesis of clay-rich soils developed on limestone in humid temperate climates has not been sufficiently investigated. Therefore, this study aimed to evaluate the geochemical and mineral compositions and properties of Luvisols (10 profiles) from the Dinaric karst region and identify the geochemical indicators of eluvial–illuvial processes. The geochemical and mineral differences between the A, E, and Bt horizons could be explained by the pedogenic processes of biorecycling, migration, isomorphic substitution in minerals, surface adsorption to clay or Al/Fe oxide minerals, and precipitation from the soil solution. Illuviation is evident in the downward increase in Al2O3, Fe2O3, MgO, K2O, Ba, Co, Cr, Ga, Ni, Sc, Th, U, V, Y, and REE. Despite differences in the geochemical characteristics of the 10 studied profiles, eluvial–illuvial processes outweighed the heterogeneity of the soils from different sites and the probable contribution of allochthonous material to the soil. We established new textural and geochemical indicators that could explain the differences among horizons and profiles in light of the polygenetic origin of soil material and pedological processes.
Aim
Freshwater subterranean amphipods with low dispersal abilities are known from both sides of the impermeable barrier, the Adriatic Sea. We tested the hypothesis that historical marine ...regression–transgression cycles shaped the distribution patterns of subterranean amphipods through repeated cycles of dispersal and vicariance against the hypothesis that subterranean amphipods colonized both sides of the Adriatic Sea independently.
Location
Western Balkan Peninsula, Adriatic Sea Islands and Apennine Peninsula, Europe.
Taxon
Genus Niphargus, a clade of freshwater subterranean amphipods (Crustacea: Amphipoda).
Methods
The taxonomic structure of the studied clade was revised using unilocus species delimitation methods. The timeframe of cladogenetic events was inferred using a multi‐locus time‐calibrated phylogeny and compared to the main regression–transgression events in the Miocene and Pleistocene. The geographical origin of the studied clade, species range expansions and contractions, as well as vicariance events were assessed through modelling of historical biogeography.
Results
Subterranean amphipods of the genus Niphargus, found on both sides of the Adriatic Sea, form a monophylum. The reconstructions of ancestral ranges suggest that the clade emerged in the Balkan Peninsula, dispersed three times independently to the Apennine Peninsula and once back to the Balkans. Adriatic Islands were colonized multiple times, predominantly from the Balkan Peninsula. The dispersal–vicariance events correspond to historical regression–transgression cycles in Miocene and Pleistocene.
Main conclusions
Marine regression–transgression cycles apparently shaped the distribution patterns of subterranean amphipods while the alternative hypothesis received no support. The actual distribution of subterranean faunas apparently reflects old biogeographical events.
Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) is routinely used as a rapid and cost-effective method for pathogen identification in clinical settings. In ...comparison, its performance in other microbiological fields, such as environmental microbiology, is still being tested, although isolates of environmental microbes are essential for in-depth in vivo studies of their biology, including biotechnological applications. We investigated the applicability of MALDI-TOF MS for the identification of bacterial isolates from a highly oligotrophic environment — Dinaric Karst caves, which likely harbor specific microorganisms. We cultured bacteria from the shell surface of the endemic mussel
Congeria jalzici
, one of the three known cave mussels in the world that lives in the Dinaric karst underground. The bacterial isolates were obtained by swabbing the shell surface of mussels living in microhabitats with different amounts of water: 10 air-exposed mussels, 10 submerged mussels, and 10 mussels in the hygropetric zone. A collection of 87 pure culture isolates was obtained, mostly belonging to the phylum Bacillota (72%), followed by Pseudomonadota (16%), Actinomycetota (11%), and Bacteroidota (1%). We compared the results of MALDI-TOF MS identification (Bruker databases DB-5989 and version 11, v11) with the results of 16S rDNA-based phylogenetic analysis, a standard procedure for bacterial identification. Identification to the genus level based on 16S rDNA was possible for all isolates and clearly outperformed the results from MALDI-TOF MS, although the updated MALDI-TOF MS database v11 gave better results than the DB-5989 version (85% versus 62%). However, identification to the species-level by 16S rDNA sequencing was achieved for only 17% of isolates, compared with 14% and 40% for the MALDI-TOF MS databases DB-5989 and v11 database, respectively. In conclusion, our results suggest that continued enrichment of MALDI-TOF MS libraries will result with this method soon becoming a rapid, accurate, and efficient tool for assessing the diversity of culturable bacteria from different environmental niches.
Abstract
We provide a comparative population genetic study of the elusive amphibian, Proteus anguinus, by comparing the genetic diversity and divergence among 4 cave populations (96 individuals) ...sampled in the Dinaric Karst of Croatia. We developed 10 variable microsatellite markers using pyrosequencing and applied them to the 4 selected populations belonging to 4 different cave systems. The results showed strong genetic differentiation between the 4 caves corroborating with previous findings suggesting that Proteus might comprise several unrecognized taxa. Our results confirmed that gene flow should be high within the caves, whereas it is low between hydrographic systems since geological periods. Finally, we conclude that the high genetic subdivision suggests the necessity of treating the 4 studied Proteus populations as evolutionary significant units.
A new species of minute cave-dwelling centipedes, Lithobius radjai sp. nov., is described and illustrated based on specimens collected from a cave in Croatia (Balkan Peninsula). A detailed account of ...the morphology of specimens of both sexes is provided. Furthermore, a brief comparison with other morphologically similar species is presented, and the type locality of the new species is mapped.
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