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Povzetek: We studied spatio-temporal distribution of hyporheic invertebrate community at the stream-reach scale in the River Bača on three sampling occasions (January, March, May) in 2005. On each sampling occasion, invertebrates were collected from the shallow hyporheic zone (RB1; depth 30-60 cm, 3 replicates), and deeper hyporheic zone (RB2; depth 60-90 cm, 2 replicates) in the river bed, and adjacent gravel bar (GB; depth 60-90 cm, 3 replicates) using Bou-Rouch piston pump. Concurrently, temperature, conductivity and oxygen were measured in the surface water and in hyporheic water at each sampling station. Differences in hyporheic community between dates and habitats were analysed by using two-way ANOVA (dates and habitats as fixed factors) and explored by principal component analysis (PCA). Altogether, 21,657 specimens from 63 taxa were collected. Cyclopoida juveniles, Leuctra sp. (Plecoptera), Chironomidae (Diptera), Acanthocyclops vernalis (Fischer, 1853) and Diacyclops languidus (G. O. Sars, 1863) were the most abundant in the samples. Two-way ANOVA showed significant differences between habitats (RB1 and GB), but no differences between dates when using taxonomic richness as dependent variable. No differences between habitats and dates were calculated when invertebrate densities were applied. PCA of hyporheic invertebrate data showed a gradient in community composition from shallow hyporheic zone (RB1) to deeper hyporheic zone (RB2) and gravel bar (GB). The differences were most probably due to different sediment composition in the studied habitats and less frequent disturbances due to floods in deeper layers and lateral gravel bars.
Ključne besede: stream reach, hyporheic zone, invertebrates, distribution (biology), community composition, spatial and temporal distribution
Objavljeno v DiRROS: 12.03.2025; Ogledov: 210; Prenosov: 172
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Povzetek: Interstitial water that occupies the pore spaces within unconsolidated sediments is a unique habitat, inhabited by surface as well as exclusively subterranean species (stygobionts). The best studied of all interstitial habitats is the hyporheic zone, an interface between surface water and groundwater (phreatic zone) environments. The Sava River in central Slovenia (i.e., at the Ljubljana alluvial plain) readily qualifies as one of the global hotspots of interstitial biodiversity, while data from other river sections are lacking. In 2015, we sampled two gravel bars on the final Slovenian section of the river (Eastern Slovenia), and collected nine samples per site using the Bou-Rouch pumping method. At »Čatež ob Savi« and »Obrežje« sites, at least 26 invertebrate species with 14 stygobionts and 25 invertebrate species with 13 stygobionts were identified, respectively. Altogether, 33 invertebrate taxa with 16 stygobionts were recorded, which increased the previously known interstitial stygobiotic richness of the Sava River in Slovenia by eight species (to 37 species). Three species of the stygobiotic amphipod genus Niphargus were recorded in Slovenia for the first time, one of which is even a new species to science. We discuss the novel results in the context of current national conservation practices.
Ključne besede: interrstitial fauna, hyporheic, stygobionts, endemic species, Bou-Rouch pumping method, Sava River, Slovenia
Objavljeno v DiRROS: 12.03.2025; Ogledov: 241; Prenosov: 186
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Povzetek: Prispevek predstavi zgodovino in razvoj revije Natura Sloveniaev 25 letih izhajanja, od 1999 do 2023. Izpostavljeni so začetki revije, ozadje in namen revije ter kratka analiza števila prispevkov, avtorjev in taksonomskih skupin, ki jih prispevki naslavljajo, vključno s pregledom odmevnosti izbranih prispevkov. V 25-letih je bilo v reviji objavljenih 286 prispevkov, ki jih je pripravilo 320avtorjev. Prispevki se osredotočajo na območje Slovenije in največkrat predstavljajo razširjenost vrst, objavljeni pa so tudi zapisi za druga območja iz osrednje in jugovzhodne Evrope, ki obravnavajo širše tematike povezane z ekologijo in naravovarstvom. Visoko citiranost in znanstveno odmevnost dosegajo zlasti prispevki, ki predstavljajo nacionalne sezname vrst ali poročajo o novih ali prvih opažanjih vrst v državi. Velika večina prispevkov je osredotočena na posamezne taksone, najpogosteje žuželke z redovoma metuljev in kačjih pastirjev. V 25. letu izhajanja prehaja revija v so-izdajanju Biotehniške fakultete Univerze v Ljubljani in Nacionalnega inštituta za biologijo v okvir Založbe Univerze v Ljubljani in prične uporabljati nov portal za oddajo in obravnavo rokopisov. V tem letu tudi prvič izide tretja, tematska številka revije. Po četrt stoletja rednega izhajanja zaseda Natura Sloveniae pomembno mesto v slovenski znanstveni periodiki s področja biologije in nadaljuje svoje poslanstvo objavljanja izvirnih znanstvenih prispevkov s področja favnističnih, florističnih, biogeografskih, biodiverzitetnih in ekoloških raziskav v osrednji in jugovzhodni Evropi, ter vzpodbujanja mladih piscev k objavi svojih terenskih opažanj.
Ključne besede: Slovenija, floristika, favnistika, biodiverziteta, ekologija, naravovarstvo, terenska biologija, izvirni znanstveni prispevki
Objavljeno v DiRROS: 04.03.2025; Ogledov: 376; Prenosov: 133
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Povzetek: Subterranean ecosystems (comprising terrestrial, semi-aquatic, and aquatic components) are increasingly threatened by human activities; however, the current network of surface-protected areas is inadequate to safeguard subterranean biodiversity. Establishing protected areas for subterranean ecosystems is challenging. First, there are technical obstacles in mapping three-dimensional ecosystems with uncertain boundaries. Second, the rarity and endemism of subterranean organisms, combined with a scarcity of taxonomists, delays the accumulation of essential biodiversity knowledge. Third, establishing agreements to preserve subterranean ecosystems requires collaboration among multiple actors with often competing interests. This perspective addresses the challenges of preserving subterranean biodiversity through protected areas. Even in the face of uncertainties, we suggest it is both timely and critical to assess general criteria for subterranean biodiversity protection and implement them based on precautionary principles. To this end, we examine the current status of European protected areas and discuss solutions to improve their coverage of subterranean ecosystems.
Ključne besede: ecology, subterranean ecosystems, biodiversity, protected areas, environmental assessment, environmental indicators, environmental protection
Objavljeno v DiRROS: 04.03.2025; Ogledov: 238; Prenosov: 117
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Povzetek: Dams and reservoirs are a common and globally widespread anthropogenic disturbance with documented negative effects on riverine and riparian habitats. The two most well-known impacts of river damming are longitudinal fragmentation of surface running waters and a shift from lotic habitats towards habitats with lentic characteristics that affect the benthic and pelagic communities. However, there is very little empirical evidence about the effects of damming on the aquatic fauna inhabiting interstitial habitats extending in and alongside the river-bed (i.e., hyporheic zone). In this study, we investigated the patterns in the interstitial community composition upstream, downstream and within the reservoir that was formed 80 years ago, when the river was dammed for the hydropower production. We used the rare opportunity to directly access the bottom of the reservoir drained due to dam maintenance in January 2018, to compare physical, chemical and faunistic data from the reservoir area, with those from downstream and upstream reaches of the two gravel bed rivers that are flowing into the reservoir. We sampled the interstitial invertebrate communities at seven locations, using a Bou-Rouch pump at two depths (30–60 cm and 60–90 cm within the river bed) and at three sampling points within each location. At the same sampling points we measured also physical and chemical parameters (temperature, conductivity, oxygen and pH). The interstitial water from the deepest point of the drained reservoir had substantially lower oxygen concentration, lower pH, and higher conductivity than water from the other sampling localities. This was also the site where taxa richness was lowest, and only one obligate groundwater species (i.e. stygobiont) was found. Most probably, the changes in morphology of the river channel and speed of water flow due to damming, which increased sedimentation rate and clogging of interstitial habitat, resulted in such large differences in environmental conditions and invertebrate community composition. This study provides rare empirical evidence of the effects of damming on the river interstitial habitats and fauna within the reservoir area. We recommend that environmental impact assessments conducted prior dam constructions should include also assessment of the effect of river damming on the interstitial communities. These organisms are playing important role in driving important ecosystem processes, such as organic matter degradation on one hand, and on the other hand, are composed of many rare and endangered species that need to be protected.
Ključne besede: damming, interstitial habitats, subterranean fauna, invertebrate communities, stygobionts, dam, hydropower, environmental impact
Objavljeno v DiRROS: 22.11.2024; Ogledov: 421; Prenosov: 204
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