Nina Sajna

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Verified

Nina verified their affiliation via an institutional email.

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• Ph.D.
• Professor (Associate) at University of Maribor

Using a model of resource acquisition, we studied species competition in a case where resources limit population growth. Our model is based on calculations of the distribution of individuals of single or multiple species over consumed resources. Calculations show that, as equilibrium is reached in purely resource competitive systems, the density of...

A late successional and small old peri-urban forest, differing more in species richness than in community quality (due to the presence of ancient forest understorey species), experienced the impact of an exceptionally strong natural disturbance: a 100-year recurring flood. We were able to compare the 1-year old baseline data from permanent plots wi...

This contribution serves to formally report the first record of the non-native Asian seed beetle Megabruchidius dorsalis in Slovenia, found in 2017 and 2018 in Maribor. Within the range known at present in Europe this species has found a new food source – the seeds of the ornamental North American tree species Gleditsia triacanthos. From seeds coll...

Novel interactions between introduced and native species commonly occur and can even be predicted from existing native interactions in a certain area. However, novel interactions between two species both alien to a region are less common and can result in intriguing relationships. In this study, we investigate how the North American honey locust Gl...

Loss of habitat and biological invasion are the main threats to biodiversity. In intensive agricultural or urban landscapes, forest fragments, even if they are small and isolated represent biodiversity refugia. Environmental variables such as landscape structure, abiotic conditions and anthropogenic disturbance affect the biodiversity of the fragme...

The monitoring of domestic cats' prey brought home was conducted between the 13th of March and the 1st of May 2023 in two residential areas near Maribor, Slovenia. This study aimed to provide information about the amount, diversity, and frequency of prey that the cats captured to identify the predatory impact of domestic cats in peri-urban areas. W...

Most trees and other woody plants growing within urban areas are deliberately cultivated native or non-native plants. Opportunities for spontaneous establishment and spread of woody species are scarce in an urban environment, especially if the establishment begins from seeds. We hypothesized that urban hedges might offer safe sites for the spontane...

The article presents the history of the journal Natura Sloveniae over the 25 years, from 1999–2023, of its publication. The main aim of the journal is highlighted, as well as a brief analysis of the number of contributions and authors, the taxonomic groups covered in the articles, including an overview of the citation success of the articles publis...

Table S1. Physical and chemical parameters of the environment measured at 10 permanent sampling points along the thermal stream Topla in 2015. Table S2. Morphological and ecophysiological characteristics of P. stratiotes measured at 10 permanent sampling plots along thermal stream Topla.

Thermally abnormal waters represent safe sites for alien invasive plants requiring warmer conditions than provided by the ambient temperatures in the temperate zone. Therefore, such safe sites are frequently inhabited by tropical and sub-tropical plants. By performing a literature review we assessed that at least 55 alien aquatic plant taxa from 21...

The main species composition drivers in temperate deciduous forests are environmental conditions, a stand's age and the site history, e.g., the succession stage and past land use, as well as disturbance regime and current management. We compared plant species diversity and composition in late successional and ancient forests, co-occurring on the sa...

Ambrosia artemiisifolia is North American plant species established and invasive in Europe. In 2013 its natural enemy, chrysomelid beetle Ophraella communa was first recorded in Italy and Switzerland. Since then, it has been spreading spontaneously and unintentionally with transport across Europe. Until now, it has been recorded only in the southwe...

To tackle global biodiversity loss, we will need to sustain biodiversity beyond protected areas. Here we present a case study of a rare and threatened native species Helleborus dumetorum. First, we assessed by laboratory experiments if H. dumetorum has a competitive advantage over weeds because of its allelopathic potential; secondly, we reviewed t...

In this paper, we report two new locations of the alien invasive seed beetle Megabruchidius dorsalis in Zagreb, Croatia. Additionally, we confirm for the second time the presence of M. dorsalis at one location in the same city. All beetles were reared from mature Gleditsia triacanthos pods collected from the ground (three locations) and from trees...

Fragmentation is one of the major threats to biodiversity. In a fragmented landscape, forest specialists are losing suitable forest habitats with specific site and microclimate conditions, which results in their local extinction. Conversely, the invasion of alien species is facilitated by open forest areas and increased boundaries between forest fr...

Azijski hrošč semenar Megabruchidius dorsalis, ki se razvija v semenih azijskih vrst gledičevk (Gleditsia), je bil v Evropi prvič zabeležen v Italiji leta 1989, v Sloveniji pa prvič v Mariboru leta 2017. Pojavlja se še v 15 drugih evropskih državah. V novem okolju je vrsta preskočila na dva nova gostitelja iz Severne Amerike, trnato gledičevko (Gle...

Temperate alluvial, riparian and lowland forests are the European forests with the greatest presence of invasive alien plants. Consequently, identifying the environmental conditions for and other drivers behind the establishment of invasive species in natural forest communities is crucial for understanding the invasibility of these habitats. We foc...

Asian seed beetles of the genus Megabruchidius have been recorded recently in many European countries. Our contribution serves to formally report the first records of M. dorsalis in Bosnia and Herzegovina, Montenegro and Albania and the first record of M. tonkineus in Montenegro, all found in 2021. Both species develop inside the hard seeds of the...

Aims: Changes in soil chemistry after invasion by bracken (Pteridium aquilinum) have been studied in heathlands, but comparable studies in meadows are lacking. We investigated if bracken invasion into P-deficient meadows alters the soil nutrient-resource pool, as well as the mechanisms behind it linked to soil processes and bracken nutrition. Furth...

Hladnikia pastinacifolia, the most prominent endemic plant species in Slovenia, is rare and protected because it is a stenoendemic and paleoendemic species restricted to area of Trnovski gozd (W Slovenia). However, this species can be found in various habitats. The disparity between the non-specific habitat preference of the species and its rarity...

Insect herbivores, whose larval stages live and feed inside a plant leaf, are expected to have an impact on the leaf beyond the actual tissue damage. They might influence leaf photosynthesis. Here, we provide a brief insight by studying a simple model relationship between the spring geophyte ramsons Allium ursinum with short-lived green leaves and...

Even though plants represent an essential part of our lives offering exploitational, supporting and cultural services, we know very little about the biology of the rarest and most threatened plant species, and even less about their conservation status. Rapid changes in the environment and climate, today more pronounced than ever, affect their fitne...

The seed beetle Megabruchidius dorsalis is an alien species first found in Europe in 1989 in Italy. Since then, it has been recorded in many European countries, developing inside the seeds of the ornamental trees Gleditsia triacanthos and Gymnocladus dioicus. Mature G. triacanthos pods were collected from the ground in Zagreb, Croatia in February 2...

The aim of this professional paper was to present certain thematic teaching units that are practically processed in the form of fieldwork within the courses "Phytocenology" and "Ecology of habitats and plant communities", which are held at University of Zagreb Faculty of Agriculture. The fieldwork took place in the wider area of Plomin and Plominsk...

Horticulture is an important source of alien plant species that could potentially escape the garden fence, survive in nature, reproduce abundantly and finally became harmful to natural ecosystems (i.e. invasive). Additionally, residential garden owners promote the invasion of alien species by dumping garden waste in nature. A surprisingly high numb...

Urban areas with numerous backyard gardens where ornamental plants are planted are major source of alien plants propagules that might spread into natural and semi natural habitats such as forests. In our study, we investigated occurrence and frequency of alien plan species in urban forest (N 46°30’32.28”; E 15°41’7.26”) located between settlements...

Recent studies from Central Europe show increased numbers of alien plant species in forest ecosystems. Various forest communities remarkably differ in susceptibility to invasions, while lowland fragmented forests are among the most invaded. Distribution of alien plants in forest fragments is determined particularly by fragment spatial characteristi...

Recent studies suggest that environmental filtering is the main mechanism that controls the establishment of alien plants into native plant communities. It is also known that traits of introduced species should be dissimilar from the traits of native species only to a certain degree to enable establishment and invasiveness at the same time. Several...

The rare orchid, Nigritella lithopolitanica is endemic to species-rich mountain grasslands of the south-eastern Alps with the majority of its distribution area in Slovenia. We examined phenotypic variation in morphological and reproductive traits among seven of 16 extant populations in relation to the floristic composition and stature of the grassl...

Taking care of our oral health is a live-long activity we are engaged in daily from our early years. It is important that we are well informed to autonomously choose those activities. Therefore, Primary school pupils learn within different subjects about importance of oral health. We focused on widely discussed controversies in this matter: a) merc...

Some species intrinsically have a high invasiveness capacity, shown by high phenotypic plasticity and rapid growth, enabling a wide distribution across their native habitats and successful invasion in the introduced range. For such species, information from native habitats is critically important. An example is Glechoma hederacea, native to Eurasia...

Coexistence of congeneric dry grassland species presents an interesting opportunity to evaluate traits of closely related co-occurring species. Coexisting congeneric species, exhibiting common traits, are expected to experience strong niche-overlap, which can intensify competition. Mechanisms that enable coexistence should also reduce competition....

The present-day diversity of European flora in temperate mountain ranges was mainly formed by the negative effects of Pleistocene glaciation, which caused extinctions, restricted survival in situ , and subsequent re-colonization. Only rarely can we find species that have retained the molecular information of in situ survival. One such example is th...

The objective of the present study was the cryopreservation of monotypic endemic Hladnikia pastinacifolia Rchb. shoot tips from an in vitro culture, via encapsulation-dehydration (ED) or encapsulation-vitrification (EV). For all tested genotypes, the highest rates of shoot regrowth and multiplication were obtained after overnight preculture in 0.4...

Subterranean habitats are known for their rich endemic fauna and high vulnerability to disturbance. Many methods and techniques are used to sample the biodiversity of terrestrial invertebrate fauna in caves, among which pitfall trapping remains one of the most frequently used and effective ones. However, this method has turned out to be harmful to...

Road salting in winter, which improves the safety of road travel, has a strong impact on species inhabiting road verges, since it creates habitats with increased salinity. Higher levels of soil salinity represent a habitat that can be occupied by plants exhibiting special adaptations and tolerance. As a result, Dittrichia graveolens, which is indig...

Even though Alliaria petiolata is a globally important invasive plant, for Europe it is a native humble understory species. I studiedthe population characteristics of A. petiolata in its native range (NE Slovenia) by evaluating its demographic structure (e.g. population size, density, plant fruit production) and herbivory damage in different habita...

Subterranean habitats are known for their rich endemic fauna and high vulnerability to disturbance. Many methods and techniques are used to sample the biodiversity of terrestrial invertebrate fauna in caves, among which pitfall trapping remains one of the most frequently used and effective ones. However, this method has turned out to be harmful to...

Nowadays, biological systems are under immense impact from human activities, not only locally but globally as well. Of particular concern is the effect on biological diversity, which is pushing 20–30% of all known species toward extinction. The most profound impact on biodiversity is made by human-induced global climate change, followed by other ne...

Most organisms are able to survive shorter or longer exposure to sub-zero temperatures. Hypothetically, trogloxenes characterized as not adapted, and troglophiles as not completely adapted to thermally stable subterranean environment, have retained or partially retained their ability to withstand freezing, while most troglobionts have not. We teste...

We studied the anatomy of a rare narrow endemic species belonging to the Slovenian flora – Hladnikia pastinacifolia Rchb. Hladnikia is a monotypic genus with distinct taxonomic position within the Apiaceae family. The anatomical characteristics revealed by light and fluorescence microscopy provided new insights regarding the pollen, leaf and root c...

To understand changes in biodiversity, we must take into consideration at least the effects of global warming like increased droughts, the shift in plant phenology with the lengthened vegetation period, and the possibility that alien species might benefit from them. For better predictions whether non-native species could benefit from global change...

The persistence of C. pumilio L. (Asteraceae) in time is an issue which is fundamental for conservation measures since the species is rare and often endangered. Therefore we tried to evaluate persistence as a consequence of plant longevity and its survival capacity. We estimated species’life-span by counting the number of rings present in root. Bec...

Anatomical features of Centaurea pumilio root. Red color is the result of histochemical reaction of phloroglucinol with lignin contained in cell walls. (a) Cross-section of the root. (b) Group of vascular elements in one growth ring of one vessel ray. (c) Longitudinal (radial) section of the root revealed the presence of reticulate type of secondar...

According to recent molecular analyses of Salicornia, we revised the annual glassworts from the Croatian coast, classified until now only as Salicornia europaea. Two species, a diploid Salicornia patula and a tetraploid S. emerici were recognized. They can be easily distinguished by floral characters, but not only by their habitus, which varies ext...

A semi-natural wet meadow, dominated by Carex rostrata, experienced a natural geogenic CO2 enrichment of soil [CO2] and a small layer of air above the surface throughout the year, and occasional flooding in autumn. We expected such conditions to be tolerated by flood tolerant plant species, which might even benefit from CO2 enrichment. We examined...

Hladnikia pastinacifolia Rchb., a narrow endemic, has an extremely restricted distribution in Trnovski gozd (Slovenia), despite the presence of many sites with suitable habitats. We compared the morphological traits of plants from different populations and habitats. The overall pattern showed that the smallest plants, with low fruit number, are fou...

Two Umbelliferous tall herbs – Laserpitium siler and Grafia golaka tend to form monodominant stands in the montane belt of the North Adriatic Karst after grassland abandonment. The germination and development of shade-tolerant species of further successional stages could be facilitated by favorable climatic conditions, measured in the canopy, but c...

The impact of grazing has been discussed in many organisms, and it has been shown that it has considerable influence on the structural variation of vegetation, resulting in its tussocky appearance. Such spatial heterogeneity results in plants formations that facilitate other species by providing safe sites against predation and physical stress. On...

Measurements of thermo- and hygropreference in Leiobunum roseum were carried out in the rocky-scree torrent gorge of Golobnica on the Trnovski gozd Karst Plateau in western Slovenia. This is one of the habitats of the endemic Slovenian Apiaceae plant Hladnikia pastinacifolia, and the southernmost habitat of L. roseum. This species has been confirme...

In the present study, we investigated the species richness and species composition in relation to light and management regime in remnants of wooded meadows within the riparian forests along the middle Drava River in Slovenia. 41 plots of still managed and, at different time periods (<5yrs, 5–15yrs, >15yrs), abandoned riparian wooded meadows (RWM) w...

The genetic variability of four pre-determined morphotypes of Salicornia (S. patula, S. emerici, S. veneta and the “saline type”) from 10 locations on the Gulf of Trieste coast were studied by means of ploidy level estimation using flow cytometry and by molecular DNA analysis of ITS regions of nrDNA and cpDNA. Two groups, the diploids and tetraploi...

Goričko Landscape Park is a well-preserved example of typical Central-European agricultural landscape. We used modified PHYSIS typology to describe and classify different habitat types (HT), especially the riparian stream corridors and patches (RSCP)—habitats of riparian woody stands occurring outside the closed woodland. The RSCP of Goričko were c...

We report about successful winter survival of a tropical plant Pistia stratiotes in a natural thermal stream Topla in Slovenia in temperate climate zone in central Europe. Only 2 years after its first occurrence in 2001 P. stratiotes managed to cover most of the water body where the thermal springs cause an elevated temperature (>17 °C year round)....

A draft history of the artificial Stjuža coastal lagoon was reconstructed on the basis of old maps (1804 and 1873); and compared with the present-day situation using GIS. The current data were simplified to obtain comparable categories (landscape units) with old maps. The following major landscape units were distinguished: lagoon, salt marshes, mai...