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More losses than gains? : Distribution models predict species-specific shifts in climatic suitability for European beech forest herbs under climate change
Janez Kermavnar, Lado Kutnar, Aleksander Marinšek, 2023, izvirni znanstveni članek

Povzetek: Introduction: Herbaceous plant species constitute an essential element of the flora of European beech (Fagus sylvatica) forests. There is increasing evidence that rapidly changing climate is likely to modify the spatial distribution of plant species. However, we lack understanding of the impact that climate change might have on beech forest herbs across the European continent. We investigated the possible effects of predicted increasing rates of global warming and altered precipitation regimes on 71 forest herbs closely associated with beech forests, but with varying biogeographic and climatic niche attributes. Methods: By using a total of 394,502 occurrence records and an ensemble of species distribution models (SDMs), we quantified the potential current distribution and future (2061-2080) range shifts in climatic suitability (expressed as occurrence probability, OP) according to two climate change scenarios (moderate SSP2-4.5 and severe SSP5-8.5). Results: Overall, precipitation of the warmest quarter and temperature seasonality were the most influential predictors in shaping current distribution patterns. For SSP5-8.5 scenario, all studied species experienced significant reductions (52.9% on average) in the total size of highly suitable areas (OP >0.75). However, the magnitude and directions of changes in the climatic suitability were highly species-specific; few species might even increase OP in the future, particularly in case of SSP2-4.5 scenario. The SDMs revealed the most substantial decline of climatic suitability at the trailing edges in southern Europe. We found that climatic suitability is predicted to show unidirectional northward shift and to move toward higher elevations. The gain/loss ratio was generally higher for narrow-ranged species compared to widespread taxa. Discussion: Our findings are contextualized with regards to potential confounding factors (dispersal limitation, microclimatic buffering) that may mitigate or accelerate climate change impacts. Given the low long-distance migration ability, many beech forest herbs are unlikely to track the velocity with which macroclimatic isotherms are moving toward higher latitudes, making this species group particularly vulnerable to climate change.
Ključne besede: species distribution modelling, global warming, range shift, climatic niche, biogeography, Europe
Objavljeno v DiRROS: 29.11.2023; Ogledov: 23; Prenosov: 7
.pdf Celotno besedilo (8,49 MB)
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Impact of Open-Loop Systems on Groundwater Temperature in NE Slovenia
Simona Adrinek, Mitja Janža, Mihael Brenčič, 2023, izvirni znanstveni članek

Povzetek: To achieve sustainable and efficient use of shallow geothermal resources, it is important to understand the heat transfer in the subsurface of the planned geothermal system. In the City Municipality of Murska Sobota, NE Slovenia, the use of geothermal open-loop systems has increased in recent years. Their high spatial density raises the question of possible mutual interference between the systems. By compiling geological, hydrogeological, and thermal data, obtained from the monitoring network, fieldwork, and knowledge of regional hydrogeological conditions, we have developed a transient groundwater flow and heat transfer model to evaluate the impact of the open-loop systems on the subsurface and surrounding systems. The transient simulation showed that the thermal state in the observed area is restored over the summer, when the systems are not in operation. Also, the systems do not have significant mutual interference that would affect their efficiency. However, as interest in installing new systems in the area increases, simulations of the thermal plumes of new geothermal systems are needed to ensure sustainable and efficient use of shallow geothermal energy in the future.
Ključne besede: geothermal energy, open-loop system, groundwater heat pump, intergranular aquifer, numerical modelling, thermal plume
Objavljeno v DiRROS: 19.09.2023; Ogledov: 165; Prenosov: 52
.pdf Celotno besedilo (36,17 MB)

Glued-in rods in cross laminated timber - numerical simulations and parametric studies
Boris Azinović, Henrik Danielsson, Erik Serrano, Miha Kramar, 2019, izvirni znanstveni članek

Povzetek: Numerical simulations and parametric studies of glued-in rods in cross-laminated timber have been performed. The simulations were based on 3D finite element analysis, using a cohesive surface model for the bond-lines between the laminations and the bond-line along the rod. The parametric studies investigated the influence of the glued-in length, the rod diameter, and the rod-to-grain angle on the load-bearing capacity and stiffness of the connection. The analyses showed that the load-bearing capacity generally increases with the glued-in length and the rod diameter, which agrees well with experiments. For different rod-to-grain angles, different mechanical behaviour was observed, especially considering the failure modes.
Ključne besede: glued-in rods, cross laminated timber (CLT), parametric study, nonlinear numerical modelling, glued-in length, rod diameter, rod orientation
Objavljeno v DiRROS: 13.09.2023; Ogledov: 115; Prenosov: 67
.pdf Celotno besedilo (2,66 MB)
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The influence of calcium sulfate content on the hydration of belite-calcium sulfoaluminate cements with different clinker phase compositions
Maruša Mrak, Frank Winnefeld, Barbara Lothenbach, Sabina Dolenec, 2021, izvirni znanstveni članek

Povzetek: The influence of different amounts of gypsum on the hydration of a belite-rich and a yeʼelimite-rich belite-calcium sulfoaluminate clinker (BCSA) was investigated. The hydration kinetics, phase assemblages and compressive strength development of cements prepared using yeʼelimite/ calcium sulfate molar ratios of 1, 1.5 and 2 were studied. Besides ettringite and monosulfate, aluminium hydroxide, strätlingite, C-S-H, iron-containing siliceous hydrogarnet and hydrotalcite were present as hydration products. Increasing the amount of gypsum increased the ratio of ettringite to monosulfate formed in the cement paste, lowered the amount of pore solution, delayed the dissolution of belite and ferrite, decreased the formation of strätlingite and, in the case of the yeʼelimite-rich BCSA, led to an increase in compressive strength. Increased amounts of belite in the clinker led to the formation of higher quantities of C-S-H, at the expense of straätlingite and a lower compressive strength, as belite has a lower degree of reaction than yeʼelimite and due to the formation of more C-S-H and stratlingite compared to the more space-filling ettringite. The thermodynamic model established for BCSA cement hydration agrees well with the experimental data. Compressive strength directly correlated with bound water from thermogravimetric analyses and inversely correlated with the porosity calculated from thermodynamic modelling.
Ključne besede: belite-calcium sulfoaluminate cement, gypsum, hydration, thermodynamic modelling
Objavljeno v DiRROS: 28.07.2023; Ogledov: 146; Prenosov: 111
.pdf Celotno besedilo (1,74 MB)
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Modelling the electrochemical transients during repassivation under open-circuit conditions in a neutral solution
Bojan Zajec, Tadeja Kosec, Andraž Legat, 2022, izvirni znanstveni članek

Povzetek: The responses of the current and the coupled potential to rapid depassivation have been studied on a three-electrode system under open-circuit conditions. Passivated AISI 304 stainless steel in low- and high-conductivity solutions of NaSO has been depassivated with a single, rapid scratch over the small fraction of surface of the working electrode (WE). Single- and dual-WE configurations have been implemented. Once the surface is scratched, the current and potential transients exhibit a delayed maximum and minimum, respectively, in contrast to the outcome of more common potentiostatic scratching experiments. A simple model based on the equivalent circuit has been developed to predict the observed transients and provides clear relations between the features of the transient and the parameters of the electrolyte and the electrodes. The interfacial capacitance of the electrodes’ passive surfaces proves crucial for the shapes of the observed potential and current transients. It is shown that this capacitance temporarily provides the majority of the charge for repassivation under open-circuit conditions. Possible sources of specific discrepancies between the model and the measured transients are indicated.
Ključne besede: repassivation, open circuit conditions, transient, modelling, interfacial capacitance
Objavljeno v DiRROS: 21.06.2023; Ogledov: 176; Prenosov: 79
.pdf Celotno besedilo (1,75 MB)
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Old buildings need new ideas : holistic integration of conservation-restoration process data using heritage building information modelling
Katja Malovrh Rebec, Boris Deanovič, Laurens Jozef Nicolaas Oostwegel, 2022, izvirni znanstveni članek

Povzetek: The preservation of cultural heritage and the renovation, restoration and remodelling processes could benefit greatly from Building Information Modelling (BIM) workflows being established. Currently, experts are involved with fractionated workflows, where a lot of data are missing, become lost or are duplicated by different stakeholders. All the resulting confusion severely impacts on the preservation of heritage as well as the efficiency of its restoring/remodelling/revitalizing from the point of view of current needs. Heritage information is usually conveyed through conservation-restoration plans and guidelines. In this research, a new methodology for managing the information holistically integrated into the BIM is proposed. The workflow is showcased on a demo-case building that is protected as cultural heritage. Consequently, the conservation plan becomes more accessible, not only for stakeholders in heritage, but also stakeholders responsible for the renovation, such as architects and contractors. This can result in an improved understanding of the heritage and a better revitalization.
Ključne besede: heritage building information modelling (HBIM), conservation plan, digitisation, revitalization
Objavljeno v DiRROS: 07.06.2023; Ogledov: 163; Prenosov: 133
.pdf Celotno besedilo (3,76 MB)
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Leaching and geochemical modelling of an electric arc furnace (EAF) and ladle slag heap
Mojca Loncnar, Ana Mladenovič, Vesna Zalar Serjun, Marija Zupančič, Hans A. van der Sloot, 2022, izvirni znanstveni članek

Povzetek: Old metallurgical dumps across Europe represent a loss of valuable land and a potential threat to the environment, especially to groundwater (GW). The Javornik electric arc furnace (EAF) and ladle slag heap, situated in Slovenia, was investigated in this study. The environmental impact of the slag heap was evaluated by combining leaching characterization tests of landfill samples and geochemical modelling. It was shown that throughout the landfill the same minerals and sorptive phases control the leaching of elements of potential concern, despite variations in chemical composi- tion. Although carbonation of the disposed steel slags occurred (molar ratio CO3/(Ca+Mg) = 0.53) relative to fresh slag, it had a limited effect on the leaching behaviour of elements of potential concern. The leaching from the slag heaps had also a limited effect on the quality of the GW. A site-specific case, however, was that leachates from the slag heap were strongly diluted, since a rapid flow of GW fed from the nearby Sava River was observed in the landfill area. The sampling and testing approach applied provides a basis for assessing the long-term impact of release and is a good starting point for evaluating future management options, including beneficial uses for this type of slag.
Ključne besede: EAF slag, field verification, geochemical modelling, ladle slag, leaching, release prediction, steel slag heap
Objavljeno v DiRROS: 28.04.2023; Ogledov: 223; Prenosov: 128
.pdf Celotno besedilo (4,37 MB)
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Effect of leaching on the composition of hydration phases during chloride exposure of mortar
Alisa Machner, Marie Helene Bjørndal, Harald Justnes, Lucija Hanžič, Aljoša Šajna, Yushan Gu, Benoit Bary, Mohsen Ben Haha, Mette R. Geiker, Klaartje De Weerdt, 2022, izvirni znanstveni članek

Povzetek: Mortar specimens were exposed to either a 3% NaCl solution or a 3% NaCl+KOH solution for up to 180 days. Exposure to the NaCl solution provoked much more leaching than the NaCl+KOH exposure. Leaching strongly impacted the chloride ingress profiles. The extended leaching led to a maximum total chloride content almost three times higher and a deeper chloride penetration than exposure with limited leaching after 180 days. The higher maximum chloride content seems to be linked to the enhanced binding capacity of the C-S-H and AFm phases upon moderate leaching as determined by SEM-EDS. The total chloride profile appears to be governed by multi-ion transport and the interaction of chloride with the hydration phases. Service life prediction and performance testing both rely on total chloride profiles and therefore ought to take these interactions into account.
Ključne besede: chloride binding, Friedel's salt, Kuzel's salt, ph, GEMS, thermodynamic modelling, open access
Objavljeno v DiRROS: 26.04.2023; Ogledov: 182; Prenosov: 174
.pdf Celotno besedilo (7,13 MB)
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Development of groundwater flow models for the integrated management of the alluvial aquifer systems of Dravsko polje and Ptujsko polje, Slovenia
Ada Vengust, Anja Koroša, Janko Urbanc, Nina Mali, 2023, izvirni znanstveni članek

Povzetek: With increasing exploitation of groundwater resources and implementation of various activities in their recharge areas, it is vital to conduct a comprehensive assessment of aquifers to ensure their conservation and sustainable management. In the present study, we used a comprehensive approach to conceptualise and identify the functioning of two connected aquifer systems in north-eastern Slovenia: the Quaternary porous aquifers Dravsko polje and Ptujsko polje. The study presents the conceptual models of both aquifers and their interconnectedness using separate mathematical-numerical models with the aim of ensuring an integrated management of these alluvial aquifer systems. It also highlights the importance of understanding connections between such systems for simulating groundwater flow and transport of different contaminants.
Ključne besede: hydrogeological model, Modflow model, aquifer geometry, aquifer recharge, modelling
Objavljeno v DiRROS: 27.03.2023; Ogledov: 294; Prenosov: 125
.pdf Celotno besedilo (5,58 MB)

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