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Number of results: 25
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Abstract

We talk to Prof. Magda Konarska from the Centre of New Technologies at the University of Warsaw about the “spliceosome,” the ongoing need for basic research and the importance of diversity in science.
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Abstract

During laboratory and field experiments on Nacella concinna on the west coast of Admiralty Bay, King George Island (Antarctica) clear morphological and behavioural differences between two limpet forms (N. concinna polaris and N. concinna concinna) were found. They suggested presence of genetic divergence. AFLP (amplified fragment length polymorphism) profiling of N. concinna individuals representing the two forms revealed nearly 32% of polymorphic bands; only 2% of them differed between the forms. Our results suggest that the observed phenotypic variation seems to be a result of adaptation to environ− mental conditions and not of any genetic divergence.
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Abstract

The diversity of cyanobacterial assemblages from various microhabitats in the Arctic area of Petuniabukta, Billefjorden, central Svalbard, was described. The present article contains the introductory common review of the cyanobacterial diversity and ecological data concerning main habitats, while the characteristics of individual taxonomic groups will be presented in following specific studies. Eight distinct main habitats were recognized, which differed in their species composition and especially the dominant species. More than 80 morphospecies were registered during our investigation, but only about 1/3 of them could be assigned to known and described taxa. The others require additional analyses based on modern taxonomic methods (the polyphasic approach ). The composition of cyanobacterial micro flora was comparable with assemblages in coastal Antarctica. The diversity of unicellular and colonial morphotypes (36 taxa) was higher tha n other groups. The number of filamentous species without heterocytes and akinetes, with 30 species, and heterocytous types, with only 20 species, were similar in both of these ecosystems. These numbers will be surely changed in the future, but the overall proportion of different groups will likely stay the same. In contrast to the limited species diversity, simple filamentous aheterocytous species were dominant and formed massive populations. Fewheterocy tous taxa, mostly grouped within the genus Nostoc ( N. commune –complex), were dominant in tundra soils.
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Abstract

Species composition and density of Gastrotricha in bottom sediments were studied, on an annual basis, in the littoral of the mesotrophic Lake Piaseczno (Łęczyńsko-Włodawskie Lakeland). The number of species from spring to autumn remained on the same level (from 24 in spring to 22 in autumn), but in winter in littoral of the lake there were recorded only 8 species. Species diversity expressed by the Shannon index, in spring, summer and autumn was high and amounted 2.86; 2.69 and 2.77 respectively. In winter the value of the index was significantly lower and amounted 1.80. In individual seasons the mean density of Gastrotricha valued from 50 103 indiv. m-2 during winter to 1238 103 indiv. m-2 in spring. The density of Gastrotricha in spring was more than 24 times higher than that winter. There were no significant differences in species diversity Gastrotricha from spring to autumn, although the peak abundance was recorded in the spring. It is necessary to add, that the density of Gastrotricha during the spring peak was one order of magnitude higher from that in summer and autumn. The similarity of the fauna found in winter to the fauna occurring in other seasons, is significantly low, ranging from 24 to 27%. Seasonal changes in amount and diversity of the gastrotrich fauna are probably the result of temperature changes and food availability.
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Abstract

The main purpose of the author was to determine the spatial diversity of hotel base development in the regional (voivodship) system. Assuming that many factors determine the level of hotel base development in a given area, the author has used a multidimensional approach, or more precisely – a multidimensional comparative analysis in its dynamic variant. Following the adopted algorithm, a potential set of diagnostic variables was identified on the basis of secondary information sources (date of CSO local data bank), then using factor analysis to reduce it to the final set of quasi-variables (four main factors). Based on them, a synthetic measure of the development of the hotel base of particular voivodships was constructed. This in turn allowed to determine the voivodship hierarchical structure due to particular main factors and synthetic variable, with its changes in the years 2002–2017. The voivodship were also divided into homogeneous groups, according to the value of the synthetic measure of development, as well as the direction and intensity of its temporal changes.
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Abstract

This article is devoted to the official forms in the inflection of chosen toponyms in Poland and the variety of dialectal singular and plural place names. The variety of place names often diverges from the rules of language use, and causes language users problems. The toponyms have peculiar, locally used inflected forms; the outside-linguistic (non-linguistic) factors that are social and local factors, play an important role in the inflection of place names. The local population often uses other forms than those recommended by official sources. I focus my attention on the genitive forms of toponyms because it is mainly here that one can see clear variations in the official and local inflection of place names. The material shows that the singular masculine toponyms have genitive endings: -a (in the official variety), -u (in the local variety), for example Biłgoraj, gen. Biłgoraja, but in the local dialect: biłgoraju. The singular feminine place names have genitive endings: -ej (in the official variety), -y||-i (in the local variety): Brzezowa, gen. Brzezowej, but Brzezowy in the local dialect. The plural toponyms have genitive endings: -ø, -ów, -i (-y), but in the local circulation the ending -ów is dominant and demonstrates a wider expansion in use. For example Brzózki, gen. Brzózek, in the local variety Brzuskuf; Budy, official gen. Bud, but Buduf; Burnie, gen. Burni, in the local dialect: Burniuf. The gathered material reflects a hesitation in the inflection of toponyms, as the linguistic customs and presented dialectal records of forms of genit ives of place names show a significantly diverse approach towards the Polish language.
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Abstract

The archipelago of Svalbard in the European High Arctic lies on the convergence of the Palaearctic and Nearctic flora and fauna and contains elements of both regions. The island of Hopen is located in the south east of the archipelago within the path of the cold south−westerly flowing East Svalbard Current originating in the Arctic ocean and flowing along the north Russian coast. This current is postulated as a colonization route of the invertebrate fauna of Svalbard. Few reports of the terrestrial invertebrates of Hopen exist and none of the mite suborders Oribatida or Mesostigmata. With the taxonomic confusion existing in the inventories of this important region of the Arctic, new sampling campaigns with species identified by modern taxonomic principles and with material deposited in accessible museums and collections are essential. Identified mites included six species of oribatid mites with Diapterobates notatus dominating, and five species of Mesostigmata with Zercon forsslundi forming the dominant species. None of the species collected was a new record for Svalbard and all have wide circumpolar, Palaearctic or Holarctic distributions. Dispersal to Svalbard from northern Russia is hence neither supported nor rejected. The expected oribatid and mesostigmatid diversity of the island is greater than observed from the limited sampling described here.
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Abstract

Early blight disease caused by Alternaria sp. is one of the most devastating diseases of Solanaceous crops widely distributed in Sudan. The aim of this study was to determine the genetic variation among different Alternaria isolates recovered from different Solanaceae crops showing typical symptoms of early blight disease. Infected leaves of tomato, potato, eggplant and pepper were collected from different geographical zones in Sudan. The recovered fungal isolates were identified to the genus level based on cultural and morphological characteristics. Five representative isolates were sent to the CABI Bioscience, U.K. for confirmation. The genetic relationship among the isolates was determined using the amplified fragments length polymorphism (AFLP) technique and the generated data were used to create similarity matrices using the PAST 3.01 software package. Dendrograms were constructed based on Jaccard’s similarity coefficients. A total of 70 fungal isolates was recovered from the tested plants and all of them showed morphological characteristics typical of Alternaria spp. The conidia appeared in multiple-branched chains with spore sizes in the range of 2.38−13.09 μm × 12.30−43.63 μm. Therefore, the isolates were identified as Alternaria alternata (Fr.) Keissl. The identification was then confirmed by CABI.AFLPbased dendrogram which revealed five clusters with a significant cophenetic correlation coefficient (r = 0.834) between the dendrogram and the original similarity matrix irrespective of their geographical origins. Eighteen (75%) of the Alternaria isolated from tomato leaves were clustered together in cluster I and five isolates formed two separate clusters, viz. cluster IV (T-Kh5 and T-H1) and cluster V (T-H4 and T-Med2). The remaining isolate, T-Am5, grouped with one of the potato isolates in cluster III. The other isolates which were recovered from potato, pepper and eggplants were all separated from the tomato isolates in the largest cluster.
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Abstract

Based on material collected during the BIOICE project off Iceland, the taxonomy and distribution of seventeen species (11 genera) of polychaetous annelids belonging to the family Ampharetidae (Annelida; Polychaeta) is reviewed. Eleven of these species were previously reported in the area or nearby areas: Amage auricula , Anobothrus gracilis , Glyp− hanostomum pallescens , Grubianella klugei , Lysippe fragilis , L. labiata , L. sexcirrata , L. vanelli , Samythella elongata, Sosane bathyalis and S. wireni . Five species, Amage benhami, Melinnampharete eoa, Noanelia hartmanae , Ymerana pteropoda and Zatsepinia rittichae , either never or only once reported after original description, are redescribed or discussed. A potentially new species, Amage sp., is described but not named because only one specimen is present. Several body characters of high taxonomic relevance in Ampharetidae are reviewed using SEM. The distribution of each species off Iceland is provided.
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Abstract

Antarctic pearlwort ( Colobanthus quitensis ) is one of the flowering plant species considered native to maritime Antarctica. Although the species was intensively analyzed towards its morphological, anatomical and physiological adaptation to local environment, its genetic variability is still poorly studied. In the presented study, a recently developed retrotransposon−based DNA marker system (inter Primer Binding Site – iPBS) was applied to assess the genetic diversity and differentiation of C. quitensis populations from King George Island (South Shetland Islands, West Antarctic). A total of 143 scoreable bands were detected using 7 iPBS primers among 122 plant specimens representing 8 populations. 55 (38.5%) bands were found polymorphic, with an average of 14.3% polymorphic fragments per primer. Nine of all observed fragments were represented as a private bands deployed unevenly among populations. Low genetic diversity (on average H e = 0.040 and I = 0.061) and moderate population differentiation (F ST = 0.164) characterize the analyzed material. Clustering based on PCoA revealed, that the populations located on the edges of the study area diverge from the central populations. The pattern of population differentiation corresponds well with their geographic location and the characteristics of the sampling sites. Due to the character of iPBS markers, the observed genetic variability of populations may be explained by the genome rearrangements caused by mobilization of mobile genetic elements in the response to various stress factors. Additionally, this study demonstrates the usefulness of iPBS markers for genetic diversity studies in wild species.
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Abstract

Fusarium crown rot (FCR), caused by Fusarium culmorum (Wm.G.Sm) Sacc., is an important disease of wheat both in Iraq and other regions of wheat production worldwide. Changes in environmental conditions and cultural practices such as crop rotation generate stress on pathogen populations leading to the evolution of new strains that can tolerate more stressful environments. This study aimed to investigate the genetic diversity among isolates of F. culmorum in Iraq. Twenty-nine samples were collected from different regions of wheat cultivation in Iraq to investigate the pathogenicity and genetic diversity of F. culmorum using the repetitive extragenic palindromic (REP-PCR) technique. Among the 29 isolates of F. culmorum examined for pathogenicity, 96% were pathogenic to wheat at the seedling stage. The most aggressive isolate, from Baghdad, was IF 0021 at 0.890 on the FCR severity index. Three primer sets were used to assess the genotypic diversity via REP, ERIC and BOX elements. The amplicon sizes ranged from 200–800 bp for BOX-ERIC2, 110–1100 bp for ERIC-ERIC2 and 200–1300 bp for REP. A total of 410 markers were polymorphic, including 106 for BOX, 175 for ERIC and 129 for the REP. Genetic similarity was calculated by comparing markers according to minimum variance (Squared Euclidean). Clustering analysis generated two major groups, group 1 with two subgroups 1a and 1b with 5 and 12 isolates, respectively, and group 2 with two subgroups 2a and 2b with 3 and 9 isolates, respectively. This is the first study in this field that has been reported in Iraq.
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Abstract

A total of 142 cods: 60 from the South−East Ground of Bear Island and 82 from the Pomeranian Bay (Baltic Sea) were examined for their ecto− and endoparasites. Twenty different parasite species, comprising one Myxosporea, three Cestoda, four Digenea, seven Nematoda, three Acanthocephala and two Crustacea were found. The parasite component communities comprised 1446 individuals (17 species, six higher taxa) from the Bear Island and 6588 individuals (nine species, three higher taxa) from Pomeranian Bay. The observed parasite host specificity was low, and the intensity in a single fish ranged from one to 279 specimens. The eudominant parasite species were Echinorhynchus gadi , Hemiurus levinseni and Contracaecum osculatum . The dominant parasite communities from the Bear Is − land were nematodes, but acanthocephalans dominated in cod from the Baltic Sea. It appears that one group of parasites, better adapted for the specific conditions of the macrohabitat, has replaced another. The most prevalent parasites were E. gadi , Anisakis simplex , C. osculatum and Hysterothylacium aduncum , and the mean values of crowding were the highest for E. gadi and Pomphorhynchus laevis . The nematode Camallanus lacustris was noted in this host species for the first time. Only six species of parasites were common to cod from both fishing grounds
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Abstract

The eurybathic isopod species Chelator insignis shows a wide distribution south of Iceland. We analysed 51 specimens from shelf (213–305 m depth), slope (885–891 m and 1380–1390 m depth) and deep−sea habitats (2750 m) south of Iceland with different DNA markers. A fragment of the mitochondrial cytochrome c oxidase subunit I gene (COI) was studied for 47 specimens, 16S was studied for 36 specimens, and a fragment for the 18S rRNA gene could be amplified for 11 specimens. For the COI data, specimens clustered into five distinct lineages each separated by ³ 20% uncorrected pairwise distances. Both the mitochondrial 16S and the nuclear 18S sequence data further support this deep divergence, suggesting the presence of overlooked species inside the nominal C. insignis . Populations on the shelf occurring east and west of the Reykjanes Ridge were genetically identical suggesting that this ridge is not a barrier to gene flow. However, populations from different depth ranges differed substantially. Our multi−gene analysis suggests that the newly found species likely have more narrow vertical distribution ranges and highlights a possible role of bathymetry in speciation processes.
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Abstract

This paper present the data for monitoring forest conditions and forest resource management by a local community adjacent to the Doi Laung Wildlife Sanctuary, Huaimai Sub-district, Song District, Phrae Province, Thailand. This study uses quantitative forest surveys, interviews, discussions, and descriptions of the historical context of public participation in forest management including a detailed assessment of field conditions. The findings of a forest resources inventory show that (1) from the three sampled areas, Doi Laung Wildlife Sanctuary has highest richness, followed by village #16 and #14, and (2) Huaikhon #16 implied the process of framework to maintain a healthy condition and response to community needs with collective management. The conceptual model assessment that links key group indicators and drivers is presented based on previously developed assessment models. The framework focuses on the best way to provide forest management, forest fire prevention, and firefighting as well as monitoring of Check-dam construction and other activities that support the recovery of the forest community. This paper demonstrates the general of an environmental assessment framework to applying organize environmental information to facilitate policy decision making for the sustainable development.
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Abstract

Populations of Antarctic hairgrass Deschampsia antarctica Desv. from King George Island exhibit variation in many traits. The reason for that is not evident and could be addressed to variable environmental conditions. Obviously, phenotypic variation could be due to stable or temporal changes in expression pattern as the result of adaptation. Stable changes could be due to mutations or site DNA methylation variation that modified expression pattern. Recently, metAFLP approach was proposed to study such effects. A variant of methylation sensitive AFLP (Amplified Fragment Length Polymorphism), based on the isoschizomeric combinations Acc65 I/ Mse I and Kpn I/ Mse I was applied to analyze the sequence and site DNA methylation differences between two D. antarctica populations exhibiting morphological dissimilarities. Both DNA sequence mutations and site methylation pattern alternations were detected among and within analyzed populations. It is assumed that such changes might have originated as the response to environmental conditions that induced site methylation alternations leading to phenotypic variation of D. antarctica populations from South Shetland Islands.
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Abstract

Aeromonas hydrophila is a valuable indicator of the quality of water polluted by sewage and pathogens that pose a risk for humans and cold-blooded animals, including fi sh. The main aim of this research was to evaluate anthropogenic pollution of river water based on genetic diversity of 82 A. hydrophila strains by means of RAPD, semi-random AP-PCR (ISJ) and the rep-BOX conservative repeats test. Genetic diversity of A. hydrophila was HT = 0.28 (SD = 0.02) for all DNA markers (RAPD, semi random and rep-BOX). None of the analyzed electrophoretic patterns was identical, implying that there were many sources of strain transmission. The presence of genes for aerolysin (aerA), hemolysin (ahh1) and the cytotoxic enzyme complex (AHCYTOGEN) was verifi ed for all tested strains, and drug resistance patterns for tetracycline, enrofl oxacin and erythromycin were determined. The most diverse A. hydrophila strains isolated from river water were susceptible to enrofl oxacine (HS = 0.27), whereas less diverse strains were susceptible to erythromycin (HS = 0.24). The presence of the multidrug resistance marker (ISJ4-25; 1100 bp locus) in the examined strains (resistant to three analyzed drugs) indicates that intensive fi sh cultivation affects the microbiological quality of river water.
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Abstract

This study used ISSR markers to assess the genetic diversity of a collection of 15 genotypes of Salix purpurea and 6 interspecific hybrids, employing 40 of 60 tested ISSR primers generating polymorphic amplification products. The PCR-ISSR method was adapted for S. purpurea by optimizing the annealing temperature for each primer. The polymorphism index of ISSR amplification products was 91.8% for all studied genotypes and 70.4% for S. purpurea genotypes. Nei's genetic identity statistics ranged from 0.538 to 0.958. Nei's genetic distance values were used to build a dendrogram (UPGMA) for the investigated genotypes. The dendrogram shows five clusters, and principal coordinate analysis yielded nearly the same genetic relationships among the studied genotypes. The results confirm the usefulness of ISSR markers for determining genetic diversity in S. purpurea.
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Abstract

The study addresses the challenges facing the law of the sea. Although UNCLOS is rightly described as a constitution of the law of the sea, it does not and cannot give answers to all problems and doubts that arise in practice and that are related to global warming, protection of biodiversity, legal status of genetic resources, controversy concerning shipping, delimitation of areas or the protection of underwater cultural heritage. Hence the question arises, what the ways and means of further development of the law of the sea are. Undoubtedly, one of the possibilities is to develop implementation agreements, of which the third devoted to the protection and sustainable use of marine biodiversity outside national jurisdiction is the subject of an international conference convened by the General Assembly, whose resolutions in the area of the law of the sea play an important role. Undoubtedly, also the importance of the organization of the United Nations system, such as the IMO, FAO, UNESCO, UNEP is significant. There is also the possibility of accepting agreements addressing the issues left by UNCLOS without solution or definition. Not without significance is the soft law and the practice of states as well as the position of the organs appointed by UNCLOS.
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Abstract

In a study on the click beetles (Coleoptera: Elateridae) of selected plant communities of the Lasy Janowskie Reserve, 21 species of these beetles were recorded – 10 each in riparian forests and a sub-Atlantic mesic coniferous forest, 11 in a continental mixed coniferous forest, and 6 in wet grassland communities. The numbers of species in the communities was similar to numbers recorded in other, comparable areas of Poland, with the exception of the wet grasslands. Forest species that can also occur outside of forests – Athous subfuscus and Dalopius marginatus – were dominant. The biodiversity of the click beetle fauna in the communities was at an average level. An ecological and zoogeographical analysis was carried out as well.
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Abstract

In two fish ponds in Lasy Janowskie Landscape Park 48 water mite species were caught. In the pond Momoty Duże, situated in the Lasy Janowskie reserve, more species (38), higher species diversity (3.88), and a larger share of lake fauna (33.2%) were observed than in Momoty Małe (33, 3.67 and 22.6% respectively). In the combined collected material small water body species were dominant (70.6%). Similarity between the Hydrachnidia assemblages of the two ponds was 50.1%. The large number of species and individuals caught and the high values for the species diversity index confirm the significant role of fish ponds as a habitat for water mites. A characteristic trait of the ponds was the very small percentage of vernal species and of tyrphobiontic and tyrphophilic species. Although more species and a larger share of lake fauna were found in the pond situated in the reserve (Momoty Duże) than in the pond outside the reserve (Momoty Małe), the differences in the structure of the fauna were slight. The lack of pronounced differences between the two ponds was due to their similar habitat characteristics and similar use.
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Abstract

Dratów, Krzczeń and Tomaszne lakes are among environmentally valuable reservoirs in Poland and Łęczyńsko-Włodawskie Lakeland. These are shallow eutrophic reservoirs of varied water surface. What they have in common is the fact that they are linked by Wieprz-Krzna Canal. The main aim of the present study was to determine the degree of faunistic similarity between planktonic rorifer assemblages inhabiting these particular lakes. The authors were interested to find out whether linking the lakes with the canal, as well as currently applied water exchange could affect the degree of faunistic similarity occurring between these lakes. Physical and chemi-cal analyses, as well as the studies of planktonic rotifers were carried out in the spring, summer and autumn of 2012 and 2013. They included determining the qualitative composition and the density of planktonic rotifers. The studies resulted in finding 50 species of Rotifera, with mean density ranging from 75 to 855 ind. dm-3. The dominants included the common species of Keratel-la cochlearis, Keratella cochlearis tecta, Keratella quadrata, Polyarthra vulgaris, Kellicottia longispina, Brachionus angularis, Ascomorpha odalis and Synchaeta pectinata. The results re-vealed high faunistic similarity among rotifer assemblages inhabiting a particular lake in different years, and high diversification occurring between the lakes compared in the work. The analyses showed that linking the lakes by Wieprz-Krzna Canal did not significantly affect the faunistic similarity of these particular lakes.
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Abstract

The impacts of long-term polycyclic aromatic hydrocarbons (PAHs) and heavy metal pollution on soil microbial communities functioning were studied in soils taken from an old coke plant. The concentrations of PAHs in the tested soils ranged from 171 to 2137 mg kg-1. From the group of tested heavy metals, concentrations of lead were found to be the highest, ranging from 57 to 3478 mg kg-1, while zinc concentrations varied from 247 to 704 mg kg-1 and nickel from 10 to 666 mg kg-1. High dehydrogenase, acid and alkaline phosphatase activities were observed in the most contaminated soil. This may indicate bacterial adaptation to long-term heavy metal and hydrocarbon contamination. However, the Community Level Physiological Profiles (CLPPs) analysis showed that the microbial functional diversity was reduced and influenced to a higher extent by some metals (Pb, Ni), moisture and conductivity than by PAHs.
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Abstract

Genetic diversity is often considered a major determinant of long term population persistence and its potential to adapt to variable environmental conditions. The ability of populations to maintain their genetic diversity across generations seems to be a major prerequisite for their sustainability, which is particularly important for keystone forest tree species. However, little is known about genetic consequences of demographic alterations occurring during natural processes of ecological succession involving changes in the species composition. Using microsatellites, we investigated genetic diversity of adult and offspring generations in beech (Fagus sylvatica L.) and oak (Quercus robur L.) populations coexisting in a naturally established old-growth forest stand, showing some symptoms of ongoing ecological succession from oak- to beech- dominated forest. In general, adult generations of both species exhibited high levels of genetic diversity (0.657 for beech; 0.821 for oak), which, however, depended on the sets of selected genetic markers. Nevertheless, several symptoms such as differences in genetic diversity indices between generations, significant levels of inbreeding (up to 0.029) and low estimates of effective population size (48-80) confirmed the declining status of the oak population. On the other hand, the uniform distribution of genetic diversity indices across generations, low levels of inbreeding (0.004), low genetic differentiation among adults and offspring and, most importantly, large estimates of effective population size (119-716), all supported beech as a successive and successful tree species in the studied forest stand.
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