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1.
Importance of habitat context in modelling risk maps for two established invasive alien plant species : the case of Ailanthus altissima and Phytolacca americana in Slovenia (Europe)
Maarten De Groot, Erika Kozamernik, Janez Kermavnar, Marija Kolšek, Aleksander Marinšek, Andreja Nève Repe, Lado Kutnar, 2024, original scientific article

Abstract: Forests are important ecosystems that face threats from climate change and global environmental shifts, with invasive alien plant species being a significant concern. Some of these invasive species have already become established, while others are in the process of naturalisation. Although forests are a relatively stable ecosystem, extreme weather events increase their vulnerability to change, and clearings left after natural disturbances are particularly susceptible to invasion by alien plant species (IAPS). We created risk maps of two species that have spread rapidly in the last decade: American pokeweed (Phytolacca americana) and the tree of heaven (Ailanthus altissima). We prepared a generalised linear model based on the occurrence data collected within the LIFE ARTEMIS project. Eleven environmental variables were used to determine habitat characteristics. We constructed two models for each species: one covering the entirety of Slovenia and the other specifically for the forested areas in Slovenia, with the latter incorporating forest-specific variables (such as forest sanitation felling and monocultures). We observed the presence of both species at lower altitudes and in close proximity to water sources. American pokeweed tends to occur nearer to railways, while the presence of the tree of heaven is associated with areas lacking carbonate parent material and influenced by land use patterns. In forested areas, the occurrence of American pokeweed is influenced by forest habitat characteristics, such as disturbances caused by extreme weather events or the prevalence of Norway spruce monocultures. In contrast, the occurrence of the tree of heaven is influenced by more general environmental variables, such as altitude and proximity to railways. Consequently, we have generated risk maps for the entirety of Slovenia and separately for forested areas, both of which indicate similar levels of risk, particularly for the tree of heaven. The risk map for American pokeweed highlights numerous vulnerable areas, especially forest edges, which are highly susceptible to invasion. Furthermore, there is a higher likelihood of this species occurring in areas that have undergone sanitation felling. This study suggests that the production of risk maps of IAPS could be improved by focussing on habitat types and taking into account habitat-specific variables. This approach could enhance the early detection and management of these invasive species.
Keywords: American pokeweed, tree of heaven, species distribution modelling, forests, forest disturbance, habitat suitability
Published in DiRROS: 26.03.2024; Views: 26; Downloads: 11
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2.
Investigations of chemical element distributions in soil, North Macedonia—a review
Trajče Stafilov, Robert Šajn, Jasminka Alijagić, 2024, original scientific article

Abstract: This review article considers the following aspects: naturally distributed chemical elements and their enrichments, and the increased occurrence of PTEs due to anthropogenic and urban activities, as well as due to the geochemical uniqueness of certain geochemical landscapes, depending on the lithological environment. The review article is the result of many years of successful cooperation between the Geological Survey of Slovenia and the Faculty of Natural Sciences in Skopje, Ss. Cyril and Methodius University in Skopje, as well as several other institutions from North Macedonia, Russia and Romania but, also, through the voluntary and enthusiastic work of Prof. Trajče Stafilov’s PhD and Master’s students. To create the Geochemical Atlas, the territory of North Macedonia was covered with 995 sampling locations, but 16 separate areas with soil contamination were additionally sampled. The total sum of all collected soil samples was 3983 from 2449 different sampling sites in the period from 2006 to 2017. The analyses were performed at the Institute of Chemistry, Faculty of Natural Sciences in Skopje, at the Ss. Cyril and Methodius University in Skopje, North Macedonia, at the Research Institute for Analytical Instrumentation (ICIA), Cluj-Napoca, Romania, at the Joint Institute for Nuclear Research in Dubna, Moscow Region, Russia, and at Acme Labs in Vancouver, Canada. The sum of all analysed soil samples in all four mentioned laboratories was 7991 from 2006 to 2017. Using advanced mathematical methods such as multivariate statistical methods (HCA, FA, PCA) and artificial neural networks–multilayer perceptron (ANN-MP), predictions were made about the concentrations of potentially toxic elements (PTEs) and their distribution in real space. In less than two decades (2007–2023) of fruitful collaboration, a large number of scientific works have been published: 188 scientific publications, 8 geochemical atlases and 23 chapters in monographs.
Keywords: chemical elements, distribution, pollution, soil, North Macedonia
Published in DiRROS: 25.03.2024; Views: 40; Downloads: 11
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3.
Influence of geology, hydrogeology, and climate on ground source heat pump distribution in Slovenia and selected European countries
Simona Adrinek, Mitja Janža, Rao Martand Singh, 2024, original scientific article

Abstract: Shallow geothermal energy (SGE) is a renewable energy that could contribute to the decarbonatization of the heating and cooling sector. SGE is predominantly harnessed through ground source heat pump (GSHP) systems. The choice of which type of GSHP system depends on various factors. Understanding these factors is crucial for optimizing the efficiency of GSHP systems and fostering their implementation. In this paper, we have analysed the spatial distribution of GSHPs in Slovenia. We identified 1073 groundwater and 1122 ground-coupled heat pump systems with a total heat pump capacity of almost 30 MW. We quantitatively assessed the influence of geological, hydrogeological, and climate conditions on their spatial distribution. Using the χ2 test and information value method, we identified hydrogeological conditions as the most influential factor for the GSHP systems’ spatial distribution. We also performed the spatial analysis of geological and hydrogeological data in 22 European countries, including Slovenia. We collected the reported numbers of installed GSHP units in 2020 and were able to distinguish the shares of groundwater and ground-coupled heat pump systems for 12 of these countries. The analysis showed that ground-coupled heat pumps predominate in most countries, even if the natural conditions are favourable for groundwater heat pumps.
Keywords: shallow geothermal energy, renewable heating and cooling, ground-source heat pump, spatial distribution, natural condition
Published in DiRROS: 19.03.2024; Views: 46; Downloads: 16
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4.
Locally convex bialgebroid of an action Lie groupoid
Jure Kališnik, 2024, original scientific article

Abstract: Action Lie groupoids are used to model spaces of orbits of actions of Lie groups on manifolds. For each such action groupoid $M\rtimes H$ we construct a locally convex bialgebroid $\mathord{\mathrm{Dirac}}(M\rtimes H)$ with an antipode over $\mathord{\mathcal{C}^{\infty}_{c}}(M)$, from which the groupoid $M\rtimes H$ can be reconstructed as its spectral action Lie groupoid $\mathord{\mathcal{AG}_{\mathit{sp}}}(\mathord{\mathrm{Dirac}}(M\rtimes H))$.
Keywords: action Lie groupoid, coalgebra, Dirac distribution, Hopf algebroid, transversal distribution
Published in DiRROS: 16.02.2024; Views: 133; Downloads: 32
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5.
Grain size distribution of DP 600 steel using single-pass asymmetrical wedge test
Urška Klančnik, Peter Fajfar, Jan Foder, Heinz Palkowski, Jaka Burja, Grega Klančnik, 2023, original scientific article

Keywords: wedge test, hot-rolling, grain size distribution, dual-phase steel
Published in DiRROS: 07.02.2024; Views: 138; Downloads: 56
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6.
Multivariate statistical methods in determining the spatial distribution of chemical elements in soil from the Mavrovo-Rostuše region, North Macedonia
Trajče Stafilov, Robert Šajn, Kristina Petrovska, 2023, original scientific article

Abstract: In this work, the contents and spatial distributions of 19 elements (Ag, Al, B, Ba, Ca, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, P, Pb, Sr, V, Zn) in the soil of the western part of North Macedonia (Mavrovo-Rostuše region) are presented. For this purpose, a total of 66 soil samples were collected from 33 locations (33 samples of topsoil, 0-5 cm, and 33 samples of subsoil, 20-30 cm). All samples were analysed by inductively coupled plasma - atomic emission spectrometry (ICP-AES) after complete digestion with four acids (HNO3, HF, HClO4 and HCl). The obtained results were statistically evaluated and spatial distribution maps for all analysed elements were also prepared. Factor analysis was performed to reduce the number of data used and new synthetic variables (factors) were identified. Through the application of factor analysis, three geochemical associations were identified: Factor 1 (Zn, K, Cu, Fe, and Li), Factor 2 (Cr, Ni, and Mg) and Factor 3 (Ca and Al). From the obtained data and the maps of spatial distribution, it could be concluded that the distribution of the analysed elements is related to the lithology of the region. Thus, it was found that the higher content of elements of Factor 1 occurs in the eastern and southern part of the study area (middle and lower reaches of the Radika River and along the Mala River), where Mesozoic and Paleozoic carbonates as well as Paleozoic shales and Paleogene flysch prevail. Factor 2 (Cr, Ni and Mg) also represents a lithogenic association. The highest contents of the elements in both soil layers were found in the areas where Paleozoic sandstones and shales (village of Lazaropole and the area around the Mavrovo Lake) and Paleogene flysch (Rostuše village) predominate. Factor 3 (Ca and Al) also represents lithogenic association of elements. The highest content of these elements was found in the northwestern part of the study area (village of Žirovnica and along the Berička River) and in the northeastern region above the village of Brodec where Mesozoic carbonates and Paleogene flysch dominate.
Keywords: soil, heavy metals, spatial distribution, Mavrovo-Rostuše region, North Macedonia
Published in DiRROS: 04.01.2024; Views: 173; Downloads: 41
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7.
Application of multivariate statistical methods for determining geochemical trends of elements on the territory of Slovenia
Robert Šajn, Mateja Gosar, Jasminka Alijagić, Tamara Teršič, 2024, original scientific article

Abstract: The main objective of this study is to map multi-element geochemical anomalies in soil on a regional scale. We aimed to determine and evaluate the baseline geochemical values and main geochemical trends in soil that may serve as reference values against any future changes. A total of 817 topsoil samples (0–10 cm) were collected in a 5 × 5 km grid and analyzed for 35 elements using ICP-ES after multi-acid digestions (HClO4/HNO3/HCl/HF) and 53 elements using ICP-MS after modified aqua regia digestion (HCl/HNO3/H2O). The analytical results for the two different digestion methods (multi-acid digestion vs. aqua regia) were also compared for each chemical element. Multivariate statistical methods were applied to identify the geochemical trends and main sources of trace elements over the territory of Slovenia. Based on these results, seven natural and one mixed natural/anthropogenic geochemical association were established. The contents and trends of the determined factors are presented according to 8 natural units, 4 drainage areas, and geological units characteristic of Slovenia. The identified anthropogenic geochemical association combines toxic elements (Ag, Bi, Cd, Hg, P, Pb, S, Sn, and Zn). Increased values of these elements can be found in mining areas and metallurgic centers, in Quaternary sediments of the Sava River, and Adriatic Basin as the consequence of past mining activities and in the Julian Alps, where their origin could be connected to the atmospheric deposition.
Keywords: soil, geochemical mapping, distribution of geochemical elements, factor analysis, cluster analysis
Published in DiRROS: 04.01.2024; Views: 168; Downloads: 38
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8.
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, original scientific article

Abstract: 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.
Keywords: species distribution modelling, global warming, range shift, climatic niche, biogeography, Europe
Published in DiRROS: 29.11.2023; Views: 213; Downloads: 105
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9.
The potential global distribution of an emerging forest pathogen, Lecanosticta acicola, under a changing climate
Nikica Ogris, Rein Drenkhan, Petr Vahalík, Thomas L. Cech, Martin Mullett, Katherine Tubby, 2023, original scientific article

Abstract: Brown spot needle blight (BSNB), caused by Lecanosticta acicola (Thüm.) Syd., is an emerging forest disease of Pinus species originating from North America and introduced to Europe and Asia. Severity and spread of the disease has increased in the last two decades in North America and Europe as a response to climate change. No modeling work on spread, severity, climatic suitability, or potential distribution has been done for this important emerging pathogen. This study utilizes a global dataset of 2,970 independent observations of L. acicola presence and absence from the geodatabase, together with Pinus spp. distribution data and 44 independent climatic and environmental variables. The objectives were to (1) identify which bioclimatic and environmental variables are most influential in the distribution of L. acicola; (2) compare four modeling approaches to determine which modeling method best fits the data; (3) examine the realized distribution of the pathogen under climatic conditions in the reference period (1971–2000); and (4) predict the potential future global distribution of the pathogen under various climate change scenarios. These objectives were achieved using a species distribution modeling. Four modeling approaches were tested: regression-based model, individual classification trees, bagging with three different base learners, and random forest. Altogether, eight models were developed. An ensemble of the three best models was used to make predictions for the potential distribution of L. acicola: bagging with random tree, bagging with logistic model trees, and random forest. Performance of the model ensemble was very good, with high precision (0.87) and very high AUC (0.94). The potential distribution of L. acicola was computed for five global climate models (GCM) and three combined pathways of Shared Socioeconomic Pathway (SSP) and Representative Concentration Pathway (SSP-RCP): SSP1-RCP2.6, SSP2-RCP4.5, and SSP5-RCP8.5. The results of the five GCMs were averaged on combined SSP-RCP (median) per 30-year period. Eight of 44 studied factors determined as most important in explaining L. acicola distribution were included in the models: mean diurnal temperature range, mean temperature of wettest quarter, precipitation of warmest quarter, precipitation seasonality, moisture in upper portion of soil column of wettest quarter, surface downwelling longwave radiation of driest quarter, surface downwelling shortwave radiation of warmest quarter and elevation. The actual distribution of L. acicola in the reference period 1971–2000 covered 5.9% of Pinus spp. area globally. However, the model ensemble predicted potential distribution of L. acicola to cover an average of 58.2% of Pinus species global cover in the reference period. Different climate change scenarios (five GCMs, three SSP-RCPs) showed a positive trend in possible range expansion of L. acicola for the period 1971–2100. The average model predictions toward the end of the century showed the potential distribution of L. acicola rising to 62.2, 61.9, 60.3% of Pinus spp. area for SSP1-RCP2.6, SSP2-RCP4.5, SSP5-RCP8.5, respectively. However, the 95% confidence interval encompassed 35.7–82.3% of global Pinus spp. area in the period 1971–2000 and 33.6–85.8% in the period 2071–2100. It was found that SSP-RCPs had a little effect on variability of BSNB potential distribution (60.3–62.2% in the period 2071–2100 for medium prediction). In contrast, GCMs had vast impact on the potential distribution of L. acicola (33.6–85.8% of global pines area). The maps of potential distribution of BSNB will assist forest managers in considering the risk of BSNB. The results will allow practitioners and policymakers to focus surveillance methods and implement appropriate management plans.
Keywords: brown spot needle blight, BSNB, pines, species distribution model, climate change, biosecurity
Published in DiRROS: 02.08.2023; Views: 317; Downloads: 199
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10.
A meta-analysis of global fungal distribution reveals climate-driven patterns
Tomáš Větrovský, Petr Kohout, Martin Kopecky, Antonin Machac, Matěj Man, Barbara Doreen Bahnmann, Vendula Brabcová, Jinlyung Choi, Lenka Mészárosová, Zander Rainier Human, Clémentine Lepinay, Rubén López-Mondéjar, Tijana Martinović, 2019, original scientific article

Abstract: The evolutionary and environmental factors that shape fungal biogeography are incompletely understood. Here, we assemble a large dataset consisting of previously generated mycobiome data linked to specific geographical locations across the world. We use this dataset to describe the distribution of fungal taxa and to look for correlations with different environmental factors such as climate, soil and vegetation variables. Our meta-study identifies climate as an important driver of different aspects of fungal biogeography, including the global distribution of common fungi as well as the composition and diversity of fungal communities. In our analysis, fungal diversity is concentrated at high latitudes, in contrast with the opposite pattern previously shown for plants and other organisms. Mycorrhizal fungi appear to have narrower climatic tolerances than pathogenic fungi. We speculate that climate change could affect ecosystem functioning because of the narrow climatic tolerances of key fungal taxa.
Keywords: fungi, global distribution, climate
Published in DiRROS: 03.01.2022; Views: 753; Downloads: 551
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