Papers by Vladan Djordjevic
Wulfenia, 2021
The occurrence of Orchis provincialis (Orchidaceae) in the flora of Serbia is documented here for... more The occurrence of Orchis provincialis (Orchidaceae) in the flora of Serbia is documented here for the first time. This Mediterranean-Submediterranean species was found in May 2021 in the northern part of Mts Šar-Planina at Štrpce (Vrbeštica). Its morphological characteristics, currently known distribution and habitat preferences are presented. On the basis of the IUCN Red List Categories and Criteria, O. provincialis is estimated as Critically Endangered in Serbia.
Wulfenia, 2020
Terrestrial orchids in Europe inhabit a variety of vegetation types, both the forest and scrub ty... more Terrestrial orchids in Europe inhabit a variety of vegetation types, both the forest and scrub types and herbaceous vegetation. The richness and composition of orchid species and subspecies in relation to vegetation types in the central Balkans (western Serbia) were investigated in the present study. In total, the phytocoenological affiliation of 55 orchid species and subspecies were analysed. Based on presence/absence data, similarity of the orchid flora among different vegetation types (orders and alliances) was analysed using the clustering method. Orchids were recorded in plant communities from 17 classes, 31 orders and 41 alliances. The greatest number of orchid species grow in communities of the classes Festuco-Brometea, Molinio-Arrhenatheretea and Quercetea pubescentis, the orders Quercetalia pubescenti-petraeae, Brachypodietalia pinnati, Fagetalia sylvaticae as well as the alliances Fagion sylvaticae, Fraxino orni-Ostryion, Nardo-Agrostion tenuis and Arrhenatherion elatioris. The results show that the vegetation types richest in orchid taxa are those that occur over a wide range of altitudes, mainly on carbonate substrates and on various bedrock types, indicating the cumulative effect of environmental factors in determining the patterns of orchid species richness. Furthermore, Gymnadenia conopsea, Anacamptis morio, Dactylorhiza saccifera, Platanthera bifolia, Neottia ovata and Dactylorhiza sambucina were found to grow in the largest number of vegetation types, suggesting their great ecological plasticity. In total, 12 statistically significant groups of vegetation orders and 11 statistically significant groups of vegetation alliances are distinguished. The study highlights the importance of certain vegetation types in defining priorities of orchid conservation.
Journal of Applied Engineering Science, 2020
In this study concentration of toxic elements as, Cd, and Pb were determined in different soil ty... more In this study concentration of toxic elements as, Cd, and Pb were determined in different soil types and belonging orchid species Anacamptis morio vital parts, in order to examine accumulation patterns and provide new insights about the potential use of this orchid in bioremediation technology. Soils developed on limestone, serpentine, and the chert were subjected to the BCR sequential extraction. Samples of orchid roots and tubers, as underground parts, and stems, leaves, and inflorescences, as above-ground organs, were also analyzed for the content of as, Cd and Pb. During this research, it was observed that metal content in soil is directly proportional to its content in the plant, more specifically in roots, which suggests that A. morio can potentially be used in the phytostabilization of contaminated sites. Values for BCF factors showed Cd immobilization in roots regardless of the soil type. A certain level of arsenic was transferred from roots to leaves indicating the potential for accumulation of this element into aboveground organs. Assessment of the phytoremediation potential of this orchid or another plant species from diverse environments is important as it provides information about the possibility of their future application in environmental remediation programs.
Biodiversity and Conservation, 2020
Many terrestrial orchid species are known to grow in forest ecosystems, but the patterns of their... more Many terrestrial orchid species are known to grow in forest ecosystems, but the patterns of their diversity and habitat specialization have not been sufficiently explored. Niche parameters and factors influencing the distribution, abundance and composition of forest orchids in the central Balkans were investigated in the present study. Outlying mean index (OMI) analysis was used to explore ecological niches of orchids and environmental factors affecting the patterns of their distribution. Indicator species analysis was performed to identify species presenting strong affinity for specific forest and bedrock types. In addition, similarity profile analysis was applied to classify orchid taxa into meaningful groups, whereas the multi-response permutation procedure was used to analyse differences of orchid composition between forest types. Out of a total of 40 orchid species and subspecies analysed, 29 showed significant niche marginality. The first three axes of the OMI analysis explained 68.13% of total variability. Light, temperature, moisture, nitrogen and altitude were found to be the factors most effectively influencing the distribution and abundance of orchids. Seven orchids had statistically significant strong affinity for specific forest types, whereas eight orchids were statistically significantly correlated with specific bedrock types. Overall, six ecological groups of orchids were distinguished. The results suggest that specialist orchids occur at the extreme ends of the light, temperature, soil pH, moisture and altitude gradients. Moreover, most specialist orchid species were found from low to middle elevations. The results provide a useful basis for the successful design of strategies for the conservation of forest orchids.
Scientific Reports, 2020
Biotic interactions play an important role in species distribution models, whose ignorance may ca... more Biotic interactions play an important role in species distribution models, whose ignorance may cause an overestimation of species' potential distributions. Species of the family orchidaceae are almost totally dependent on mycorrhizal symbionts and pollinators, with sexually deceptive orchids being often highly specialized, and thus the interactions with their pollinators are expected to strongly affect distribution predictions. We used Maxent algorithm to explore the extent of current and future habitat suitability for two Greek endemic sexually deceptive orchids (Ophrys argolica and Ophrys delphinensis) in relation to the potential distribution of their unique pollinator (Anthophora plagiata). Twelve climate change scenarios were used to predict future distributions. Results indicated that the most important factors determining potential distribution were precipitation seasonality for O. argolica and geological substrate for O. delphinensis. The current potential distribution of the two orchids was almost of the same extent but spatially different, without accounting for their interaction with A. plagiata. When the interaction was included in the models, their potentially suitable area decreased for both species. Under future climatic conditions, the effects of the orchid-pollinator interaction were more intense. Specifically, O. argolica was restricted in specific areas of southern Greece, whereas O. delphinensis was expected to become extinct. Our findings highlighted the significant role of plant-pollinator interactions in species distribution models. Failing to study such interactions might expose plant species to serious conservation issues. Climate change is currently affecting species in various ways and the prediction of its impacts is a major scientific challenge. The effective conservation of species requires the availability of suitable and often large datasets 1-3. However, adequate species distribution data are usually lacking, and in many cases, these are of low quality and resolution. Under these constraints, species conservation actions and habitat management schemes cannot be sufficiently applied 4,5. Furthermore, the collection of such data (i.e., species records) usually requires large amounts of resources (e.g., time, funds and personnel), that are often not available 6. Specific algorithms have been developed, during the last two decades, to overcome such problems. These are best known as Species Distribution Models (SDMs) and are being used to solve various ecological or biodiversity problems (e.g., in reserve selection or in the identification of suitable habitats) in a wide range of organisms 4,7-9. In studies that use SDMs to identify potentially suitable areas in space and time, species distribution data are linked to environmental variables 7. Climatic are among the environmental variables more frequently used, due to the great importance of climate in determining species distribution at different scales, even over large geographical areas 10. Moreover, the availability of climatic data allow for examining numerous future climatic scenarios and consequently for studying the effects of these predicted future conditions on species' geographic open
Orchids Phytochemistry, Biology and Horticulture, 2020
Journal for Nature Conservation, 2019
Neottia cordata is an orchid species that exclusively occurs in Picea abies subsp. abies and Pinu... more Neottia cordata is an orchid species that exclusively occurs in Picea abies subsp. abies and Pinus sylvestris stands and forms its southernmost distribution limits in Greece. Over the last decade, it has been recorded in numerous sites, in which it forms small colonies, both in terms of population and area. This research re-evaluates the threat status of Neottia cordata based on updated chorological and population data; it also checks the effectiveness of the Natura 2000 Network as far as its conservation is concerned by applying the MaxEnt model. The recently collected data justify the classification of N. cordata as "Vulnerable". The most significant variables that affect its distribution were found to be the vegetation type and the precipitation of the warmest quarter. The results of the MaxEnt model suggest that: (i) the Natura 2000 Network is characterised by areas of higher habitat suitability values when compared to the areas that fall outside this network; and, (ii) Picea abies subsp. abies forests are more suitable for its conservation than those of Pinus sylvestris. It is concluded that the most appropriate management measure for the species conservation is the maintenance of the tree layer canopy closed.
Turkish Journal of Botany , 2018
The pollination success of two nonrewarding orchids in two coarse habitats was examined. The comp... more The pollination success of two nonrewarding orchids in two coarse habitats was examined. The comparative results of Orchis punctulata and O. purpurea showed a significant differentiation. The fruit set of O. purpurea was significantly greater compared to O. punctulata, whereas both species also had significantly higher fruit set in the grassland compared to the forest. Although the pollination success of O. purpurea was not significantly correlated with plant height, inflorescence size, or nearest neighbor distance, these factors were found to be significantly correlated to the pollination success of O. punctulata. Among these factors, the nearest neighbor distance had the highest impact on the pollination success of O. punctulata, whereas the respective effects to the individuals of O. purpurea were found to be nonsignificant. The results demonstrate that the distribution of O. punctulata at the edges of its range is not delimited by factors related to its pollination effectiveness and that other factors, mostly related to the microsite conditions, might play a more significant role in the colonization of more western areas. Moreover, suitable management treatments that would increase the light levels within the forest sites studied may also increase the pollination success and the fruit production of the studied orchids.
Bulletin of the Natural History Museum, 2018
The paper presents three new nomenclature combinations related to representatives of the orchid f... more The paper presents three new nomenclature combinations related to representatives of the orchid family. In addition, 14 taxa (species, subspecies and hybrids) of vascular flora which are newly registered for Serbia (of which 8 are autochthonous and 6 allochtonous plants) are presented. A confirmation of old or unreliable
Wulfenia, Dec 2019
Terrestrial orchids in Europe are known for their great species richness that occurs on calcareou... more Terrestrial orchids in Europe are known for their great species richness that occurs on calcareous geological substrates. However, the knowledge of orchids that grow on other bedrock types is limited. In this paper, the richness and composition of orchid species in relation to geological substrates in the central Balkans (western Serbia) were investigated. For identification of floristic similarities among the geological substrates, the clustering method based on Jaccard distances and unweighted pair-group average hierarchical sorting strategy (UPGMA) was used. In addition, multi-response permutation procedure (MRPP) was applied to analyse the differences in orchid composition between bedrock types. Orchid species and subspecies were recorded on ten bedrock types. The greatest number of orchids was recorded on limestone-dolomite (52 species and subspecies), ophiolitic mélange (40) and schists-gneiss-phyllites (31). However, a significant number of orchid species and subspecies were recorded on carbonate clastites, ultramafics, andesite-dacite-porphyrite and Quaternary sediments. On the other hand, a smaller number of orchid species were recorded on acidic igneous rocks (quartz latite and granodiorite), indicating that they are less favourable for orchids. The cluster analysis of floristic similarities allowed the identification of seven sets of geological substrates. The greatest floristic similarity was identified between limestone-dolomite and ophiolitic mélange as well as schists-gneiss-phyllites and ultramafics. However, an analysis of the composition of orchid flora in terms of abundance and frequency of orchids indicated that carbonate substrates (limestone-dolomite and carbonate clastites) differ statistically from the highest number of bedrock types. Cephalanthera damasonium, C. longifolia, Dactylorhiza sambucina, Epipactis helleborine, Gymnadenia conopsea, Neottia nidus-avis and Platanthera bifolia were found to grow on nine bedrock types, suggesting their great ecological plasticity and adaptability. This study emphasizes the important role of geological substrates in the richness, composition and distribution of orchid species in the central Balkans, pointing out that many species, known to date to occur exclusively on calcareous substrates, also grow on different silicate substrates and ultramafics. The results indicate that differences in the species richness and composition of orchids which are related to the geological substrates of their habitats should be taken into account when designing orchid conservation and management strategies.
Along with being a centre of plant species diversity and endemism, the Balkan Peninsula is one of... more Along with being a centre of plant species diversity and endemism, the Balkan Peninsula is one of the parts of Europe with the highest number of orchid taxa. However, the orchid flora in the central Balkans has not been sufficiently studied. The paper presents the distribution of ten rare and threatened taxa of Orchidaceae in the central Balkans and the southern part of the Pannonian Plain: Anacamptis papilionacea, Epipactis palustris, E. purpurata, Epipogium aphyllum, Goodyera repens, Gymnadenia frivaldii, Ophrys apifera, O. insectifera, Orchis militaris and O. spitzelii subsp. spitzelii. In addition to field investigation, checking and revision of herbarium material, literature sources were also used for supplementing distribution data. The distribution maps of these taxa in the central Balkans (Serbia and Kosovo region) and the southern part of the Pannonian Plain (Vojvodina) are created on a 10 km × 10 km UTM grid system. Data concerning their habitat preferences, population size and the estimated IUCN conservation status in the study area are provided.
Epipactis muelleri Godfery (Orchidaceae-Epidendroideae-Neottieae) was
found on Mt Tara (western S... more Epipactis muelleri Godfery (Orchidaceae-Epidendroideae-Neottieae) was
found on Mt Tara (western Serbia) for the first time in Serbia. This is currently the
single known occurrence of this species in the Central Balkans, and the easternmost
limit of its distribution in the Balkans, where it has recently been known only from
two other countries (Slovenia and Croatia). Morphological characteristics, currently
known distribution, and habitat preferences are indicated. In total, the two recorded
populations comprise five flowering individuals. The current 2012-IUCN
threatened status of E. muelleri in Serbia is estimated as Critically Endangered.
Epipactis distans Arv.-Touv., E. pontica Taubenheim and E. leptochila subsp.
neglecta Kümpel have... more Epipactis distans Arv.-Touv., E. pontica Taubenheim and E. leptochila subsp.
neglecta Kümpel have been identified as three new taxa for the flora of Serbia. E.
pontica has been recorded in western Serbia (Ivanjica), E. distans in southwestern
Serbia (Mt. Kamena Gora and Jabuka), whereas E. leptochila subsp. neglecta has
been recorded both in western and in southwestern Serbia (Mt. Golija, Ivanjica, Mt.
Pobijenik, Priboj and Nova Varoš). These are the single known occurrences of these
taxa in the Central Balkans. Morphological features, currently known distribution
and habitat preferences of these Epipactis taxa in Serbia are provided. Applying
the 2012-IUCN Red List Categories and Criteria in Serbia, E. distans and E. pontica
are estimated as Critically Endangered, whereas the current conservation status of
E. leptochila subsp. neglecta is estimated as Endangered.
Dactylorhiza sambucina (L.) Soó is a polycarpic perennial herb occurring in the Central European,... more Dactylorhiza sambucina (L.) Soó is a polycarpic perennial herb occurring in the Central European, Eastern European, and Balkan floristic provinces. At the European scale, the IUCN considers it a species of “least concern”. This paper reviews the taxonomic status, morphology, distribution, habitat requirements, mycorrhizal associations, and life cycle of D. sambucina, with special emphasis on its reproduction. We also summarize information on chromosome numbers and genetic variation. Our data from 12 years of monitoring D. sambucina in the Czech Republic show that three to four leaves have to be produced prior to flowering; plants with five and more leaves flower regularly. Juvenile plants near adult plants suggest recruitment from seeds. About 20% of our 450 monitored plants underwent dormancy (failure of mature plants to produce above-ground parts in one or more growing seasons), the maximum duration being eight years. After reappearance, these individuals were usually sterile for the next year. Mortality was highest (24%) at the seedling stage. Regarding the purple/yellow flower colour polymorphism that characterizes D. sambucina, we found no correlation between morph frequency and soil properties (pH, calcium content), population density, or altitude above sea level.
Orchids are known for their species richness, intriguing ecology, rarity and the fact that they g... more Orchids are known for their species richness, intriguing ecology, rarity and the fact that they grow in almost all terrestrial ecosystems. Although numerous studies about their ecology have been carried out concerning calcareous areas, little is known about orchids that occur in serpentine habitats. The aim of this study was to investigate the ecological preferences of orchids in serpentine and non-serpentine areas on the model of the Valjevo Mountain Range (W Serbia). Niche analysis of orchids was performed using outlying mean index analysis. Data concerning geographical coordinates, altitude, habitat type, inclination, bedrock type, light regime, soil moisture, acidity, nitrogen and temperature were used as explanatory variables. Data of 33 orchid taxa from 407 localities were analysed. The most important gradients that govern orchid distribution were geological bedrock, light regime and temperature. The results have shown that only Anacamptis morio and Gymnadenia conopsea have statistically significantly larger populations on serpentine compared with non-serpentine bedrocks. This study highlights the importance of serpentine habitats as orchid habitats, bearing in mind the occurrence of rare species and species which were found exclusively in serpentine habitats.
Dactylorhiza fuchsii (Orchidaceae) has been found on Mt. Javor (SW Serbia) as a new species in th... more Dactylorhiza fuchsii (Orchidaceae) has been found on Mt. Javor (SW Serbia) as a new species in the flora of Serbia. This is the single known locality of this species in the Central Balkans and the southernmost limit of the species' distribution on the Balkan Peninsula. Data concerning its morphology, distribution, habitat preferences, flowering period, population size and conservation status in Serbia are provided.
Epipactis purpurata Sm. (Orchidaceae) is recorded as a new species in the flora of Serbia. It was... more Epipactis purpurata Sm. (Orchidaceae) is recorded as a new species in the flora of Serbia. It was found on Mt. Maljen (Western Serbia) at 740 m altitude, and it inhabits mixed beech-fir forest. Data about the morphology, distribution, habitat, ecology, flowering period, pollination and population size of the newly-recorded species are given. The distribution map of this species in Serbia is created on a 10 x 10 km UTM grid system. In the evaluation of the species according to IUCN categories and criteria applied in Serbia, E. purpurata is classified as Critically Endangered.
Neotinea × dietrichiana (Orchidaceae), a natural hybrid between Neotinea tridentata and N. ustula... more Neotinea × dietrichiana (Orchidaceae), a natural hybrid between Neotinea tridentata and N. ustulata, has been found on the southwestern slopes of Mt Maljen (Western Serbia) for the first time in Serbia, representing its most continental record in the Balkans. Morphological and distribution data, as well as the ecological preferences of N. × dietrichiana are provided. The hybrid grows between 490 m and 510 m a.s.l., on serpentine substrate, as a member of xero-mesophilous steppe-like meadows. Hybrid specimens have been recorded at the sites where the two parental species grow in sympatry, and mostly where the population size of N. tridentata is larger than the population size of N. ustulata.
The paper represents the results of floristic and vegetation studies of ruderal habitats in urban... more The paper represents the results of floristic and vegetation studies of ruderal habitats in urban and suburban areas of the town of Žabljak (Montenegro) within the last decade of the 20 th century. A total of 279 vascular plant taxa (species or subspecies level) was recorded, as well as 6 ruderal plant communities. Detailed taxonomic-systematic, ecological and phytogeographic analyses identified certain specificities of ruderal habitats of this mountain town (1450 m a.s.l.) which is the administrative seat of the Durmitor National Park. The results of these studies support the thesis that even mountain regions, which are considered to be at low risk of ruderalization and allochthonization, are not exempt from this process. In this sense, the paper affirms the need for future complex and comparative geobotanic research of other urban mountain areas in Montenegro and the Balkan Peninsula.
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Papers by Vladan Djordjevic
found on Mt Tara (western Serbia) for the first time in Serbia. This is currently the
single known occurrence of this species in the Central Balkans, and the easternmost
limit of its distribution in the Balkans, where it has recently been known only from
two other countries (Slovenia and Croatia). Morphological characteristics, currently
known distribution, and habitat preferences are indicated. In total, the two recorded
populations comprise five flowering individuals. The current 2012-IUCN
threatened status of E. muelleri in Serbia is estimated as Critically Endangered.
neglecta Kümpel have been identified as three new taxa for the flora of Serbia. E.
pontica has been recorded in western Serbia (Ivanjica), E. distans in southwestern
Serbia (Mt. Kamena Gora and Jabuka), whereas E. leptochila subsp. neglecta has
been recorded both in western and in southwestern Serbia (Mt. Golija, Ivanjica, Mt.
Pobijenik, Priboj and Nova Varoš). These are the single known occurrences of these
taxa in the Central Balkans. Morphological features, currently known distribution
and habitat preferences of these Epipactis taxa in Serbia are provided. Applying
the 2012-IUCN Red List Categories and Criteria in Serbia, E. distans and E. pontica
are estimated as Critically Endangered, whereas the current conservation status of
E. leptochila subsp. neglecta is estimated as Endangered.
found on Mt Tara (western Serbia) for the first time in Serbia. This is currently the
single known occurrence of this species in the Central Balkans, and the easternmost
limit of its distribution in the Balkans, where it has recently been known only from
two other countries (Slovenia and Croatia). Morphological characteristics, currently
known distribution, and habitat preferences are indicated. In total, the two recorded
populations comprise five flowering individuals. The current 2012-IUCN
threatened status of E. muelleri in Serbia is estimated as Critically Endangered.
neglecta Kümpel have been identified as three new taxa for the flora of Serbia. E.
pontica has been recorded in western Serbia (Ivanjica), E. distans in southwestern
Serbia (Mt. Kamena Gora and Jabuka), whereas E. leptochila subsp. neglecta has
been recorded both in western and in southwestern Serbia (Mt. Golija, Ivanjica, Mt.
Pobijenik, Priboj and Nova Varoš). These are the single known occurrences of these
taxa in the Central Balkans. Morphological features, currently known distribution
and habitat preferences of these Epipactis taxa in Serbia are provided. Applying
the 2012-IUCN Red List Categories and Criteria in Serbia, E. distans and E. pontica
are estimated as Critically Endangered, whereas the current conservation status of
E. leptochila subsp. neglecta is estimated as Endangered.