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Povzetek: Machine learning models provide a scalable approach for predicting the diversity of eukaryotic microbial plankton from environmental predictors. However, the extent to which these models generalize to data outside the training set remains poorly quantified. In this study, XGBoost was used to predict the 18S rRNA gene Shannon Diversity Index (SDI) from seven environmental predictors derived from satellite and model data. Surface samples were collected between 2001 and 2025 at two fixed stations in the northwestern Mediterranean (BBMO and SOLA), one fixed station in the northern Adriatic Sea (VIDA), and during the HOTMIX expedition, which sampled an east-west open-sea transect across the Mediterranean Sea. Model performance was assessed using standard repeated K-fold cross-validation (CV), Leave-One-Dataset-Out CV (LODO-CV), and a blocked spatiotemporal CV that combined LODO with temporal forward chaining. Under standard K-fold CV, the model showed moderate performance (R² = 0.44, RMSE = 0.59). In contrast, performance declined substantially under LODO-CV (R² = 0.09, RMSE = 0.73), with uniformly low per-dataset generalization, a pattern also observed with blocked spatiotemporal CV. VIDA and HOTMIX sampled environmental regimes distinct from those at BBMO and SOLA, which may partly explain their poor transferability. Additionally, BBMO and SOLA, despite similar environmental conditions, exhibited poor transferability, indicating that technical differences among independently collected 18S rRNA datasets likely constrain transferability, although their effects cannot be disentangled from environmental variation. Overall, these results highlight the limitations of imbalanced training data and underscore the importance of spatially explicit evaluation, protocol standardization, and environmentally representative coverage.
Ključne besede: cross-validation, data leakage, eukaryotic plankton, machine learning, marine biodiversity, Mediterranean Sea, omics, shannon diversity index
Objavljeno v DiRROS: 29.07.2026; Ogledov: 132; Prenosov: 94
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Povzetek: Slovenia has a centuries-old tradition of managing common land, yet the state of agrarian communities at the national level remains poorly researched. This article highlights the historical development, current challenges, and status of agrarian communities in Northern and Central Upper Carniola in 2025. The analysis shows that 52 agrarian communities (48.1%) are active in the area, whereas for 56 communities (51.9%) it remains unclear whether they still operate. This draws attention to the scarcity of available data on the status of agrarian communities. Spatial analysis within Triglav National Park reveals that common land accounts for 23% of the park’s area, 23% of the Natura 2000 sites within the park, 25% of quiet zones, and 32% of the park’s protective forests, and it includes a significant proportion of valuable natural features and nature reserves. The management of common land plays an important role in preserving biodiversity and the Alpine cultural landscape. This should be taken into account when developing appropriate financial mechanisms and compensation schemes to ensure fairer management of the benefits that agrarian communities provide to the wider society through common land.
Ključne besede: agrarian communities, commons, common land, collective actions, biodiversity, alpine landscape, Upper Carniola, Triglav National Park
Objavljeno v DiRROS: 24.06.2026; Ogledov: 268; Prenosov: 198
Celotno besedilo (2,20 MB)
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Povzetek: Velika Pasica cave is situated in central Slovenia (Europe); it is 105 m long and 12 m deep, at an elevation of 670 m, and only has a 2–7 m thick roof and four permanent trickles from the epikarst zone. The second troglobiotic beetle, Anophthalmus hirtus Sturm, 1853, was described in this cave, twenty years after the first species, Leptodirus hochenwartii Schmidt, 1832, was described from Postojnska Jama cave (Slovenia). In the following decades, nine more terrestrial species and subspecies were described from Velika Pasica cave, which belong to the Mollusca, Pseudoscorpiones, Collembola and Coleoptera groups. After 2000, intensive research of the pools and trickles revealed an abundance of aquatic fauna, resulting in the description of four new species of Copepoda and two not yet determined epibiotic protozoans. A complete list of the terrestrial and aquatic fauna in Velika Pasica cave has never been published. To fill this gap, data from the literature and from intensive field work are presented here. To date, 89 terrestrial and 36 aquatic taxa have been recorded from the cave and the adjacent temporary spring and reservoir. Twenty-nine aquatic (including two epibionts) and 18 terrestrial species are strict cave-dwelling organisms. Thus, Velika Pasica cave ranks among the top global subterranean hotspots for species richness.
Ključne besede: troglobionts, stygobionts, biodiversity, epikarst, habitats, endemics, ecology, subterranean hotspots
Objavljeno v DiRROS: 02.06.2026; Ogledov: 199; Prenosov: 185
Celotno besedilo (2,11 MB)
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Povzetek: The Qualita ` Biologica del Suolo (QBS-ar) index provides a rapid, low-cost measure of soil biological quality by assigning arthropods in morphotaxonomic groups named biological forms. Although widely used, its low taxonomic resolution and reliance on expert-defined scores limits its sensitivity to subtle management effects. We therefore evaluated whether DNA metabarcoding can complement and refine QBS-based assessments by analysing soil microarthropod communities across seven agricultural treatments differing in tillage intensity and production system. Using COI metabarcoding, we compared α- and β-diversity patterns between molecular and QBS datasets, evaluated different QBS index variants in relation to DNA amplicon sequence variant (ASV) richness, and explored potential for a preliminary DNA-derived index based on QBS-like trait scoring. DNA metabarcoding resolved clear community separation among production systems and treatments that the QBS only partially detected and revealed indicator taxa characteristic of reduced-disturbance and organic management. The QBS indices distinguished major production systems but were less responsive to within-system variation. Correlations between ASV richness and QBS-ar varied among production systems, indicating contextdependent index performance. The experimental DNA-derived QBS index (QBS-DNA) retained a QBS-like trait signal, showing positive treatment-mean correlations with morphology-based QBS-ar and QBS-ar_BF, but it did not significantly distinguish treatments. These results support QBS-DNA as a proof-of-concept framework for translating trait-based soil-quality indicators into molecular biodiversity assessments. As molecular tools and trait databases expand, metabarcoding enables the development of next-generation soil biodiversity indicators based on explicit, species-level functional traits, moving beyond the constraints of classical QBS formulations while retaining their ecological intent.
Ključne besede: Mesofauna, Soil quality index, Microarthropods, Microarthropod biodiversity, COI, Molecular bioindicators, Environmental DNA, Soil biodiversity
Objavljeno v DiRROS: 11.05.2026; Ogledov: 340; Prenosov: 343
Celotno besedilo (2,31 MB)
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Povzetek: Madagascar is a biodiversity hotspot with high endemism and ancient phylogenetic diversity. We here report the discovery of Osmooka aphana gen. nov., sp. nov. from Marojejy National Park. Phylogenomic analyses place Osmooka as sister to the Australian Paraplectanoides Keyserling, 1886, and this doublet is sister to Nephilidae Simon, 1894. When proposed, Paraplectanoididae Kuntner, Coddington, Agnarsson & Bond, 2023 was exclusively Australian and monogeneric, but was predicted to contain additional, undescribed taxa. The discovery of Osmooka and its phylogenetic placement in Paraplectanoididae supports this prediction. We present a taxonomic treatment of Osmooka and Paraplectanoides, and a reappraisal of Orbipurae morphological homologies. With this new discovery, we revalidate Paraplectanoididae, Nephilidae, and Phonognathidae Simon, 1894, ranks resurrected as exclusive, monophyletic, and well-diagnosed families, whereas Araneidae Clerck, 1757 requires further redefinition. Finally, we test the hypothesis of East Gondwanan vicariant origin of Osmooka and Paraplectanoides. This scenario would predict an ancient age of their ancestor, predating the 130 Ma breakup of Gondwana. Divergence dating refutes this hypothesis by estimating their common ancestor at 57 Ma. Rather than through vicariance, the disjunct distribution of Osmooka and Paraplectanoides is best explained through Cenozoic intercontinental dispersal and/or extinctions. Potential discovery of additional paraplectanoidid diversity might better elucidate the timing, modes, and trajectories of historic dispersal and extinction events.
Ključne besede: Madagascar, biodiversity, Osmooka aphana gen. nov., sp. nov., Paraplectanoididae, spiders
Objavljeno v DiRROS: 23.03.2026; Ogledov: 328; Prenosov: 421
Raziskovalni podatki (7,31 MB)
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