20 research outputs found

    The earliest Sabiaceae fruit remains of Hungary

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    Numerous well-preserved plant-remains were discovered at the Upper Cretaceous Iharkút vertebrate fossil site (Csehbánya Formation, Bakony Mts., Hungary). A well determinable, but rare mesofossil form belongs to the Sabiaceae family. The internationally excellent Cenozoic fossil record makes the family of special phytogeographical and palaebotanical interest. Based on endocarp morphology we assigned the Iharkút specimens to Sabia menispermoides. These characters are also typical for the recent Sabia genus. KNOBLOCH and MAI described Sabia menispermoides from the Cretaceous of České Budějovice in 1986 as Sabia because of the high similarity to the recent forms. The now living Sabiaceae plants are trees, shrubs and lianas. The known representatives of the family are members of the subtropical and tropical vegetations in Asia and America. Their presence at Iharkút indicates subtropical climatic conditions of the vertebrate locality

    Multiphase response of palynomorphs to the Toarcian Oceanic Anoxic Event (Early Jurassic) in the Réka Valley section, Hungary

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    Major palaeoenvironmental and palaeoceanographical changes occurred during the Early Jurassic Toarcian Oceanic Anoxic Event (T-OAE), due to a perturbation of the global carbon cycle and a crisis in marine ecosystems. The sequence of environmental change and regional differences during the T-OAE are not yet fully understood and organic-walled phytoplankton and other palynomorphs are well-suited, but under-utilised, in research into this event. Based on quantitative palynological analyses from a black shale-bearing succession at Réka Valley in the Mecsek Mountains of southwest Hungary, five sequential palynomorph assemblages are distinguished. These reveal major shifts in organic-walled phytoplankton communities, driven by palaeoenvironmental changes. In addition, palynofacies analysis helped to document changes in the composition of sedimentary organic matter, and to quantify the terrestrial input. Assemblage 1 is characterised by a moderately diverse phytoplankton community and high levels of terrestrial palynomorphs. Assemblage 2 records a significant peak of the euryhaline dinoflagellate cyst Nannoceratopsis. Assemblage 3 is distinguished by dominance of highly opportunistic prasinophytes and the temporary disappearance of all dinoflagellate cyst taxa. Assemblages 4 and 5 represent distinctive phases of a prolonged recovery phase with low diversity phytoplankton assemblages and intermittently high levels of terrestrially-derived palynomorphs. The successive disappearance of phytoplankton taxa and the gradual takeover by opportunistic euryhaline species at the onset of the T-OAE were related to several phenomena. These include reduced salinity in the surface waters, establishment of a stable pycnocline and deterioration of nutrient recycling, followed by oxygen deficiency throughout much of the water column. The high amount of terrestrially-derived palynodebris indicates intense runoff and freshwater input, driven by the early Toarcian warming and the enhanced hydrological cycle. Comparison with coeval European successions proves that the palaeoenvironmental changes during the T-OAE were not entirely synchronous, and local factors played a crucial role in influencing phytoplankton communities. In the Mecsek Basin, regional freshening of the surface waters and increased terrestrial input due to the proximity of the hinterland had a greater influence on phytoplankton communities compared to the open oceanic setting of the Tethys to the south

    A continental record of the Carnian Pluvial Episode (CPE) from the Mercia Mudstone Group (UK):palynology and climatic implications

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    The generally arid Late Triassic climate was interrupted by a wet phase during the mid-Carnian termed the Carnian Pluvial Episode (CPE). Quantitative palynological data from the Mercia Mudstone Group in the Wessex Basin (UK) reveal vegetation changes and palaeoclimate trends. Palynostratigraphy and bulk organic carbon isotope data allow correlation to other Carnian successions. The palynostratigraphy indicates that the Dunscombe Mudstone is Julian and the lowest part of the overlying Branscombe Mudstone Formation is Tuvalian. The Aulisporites acme characterizing the CPE in Tethyan successions and the Germanic Basin is missing in the UK. The quantitative palynological record suggests the predominance of xerophyte floral elements with a few horizons of increased hygrophytes. A humidity signal is not seen owing to the dry climate in central Pangea. Also, the signal might be masked by the overrepresentation of xerophyte regional pollen and the predominance of xerophyte hinterland flora. The bias towards regional pollen rain is enhanced by the potential increase in continental runoff related to seasonally humid conditions and differences in pollen production rates and transport mechanisms. The vegetation of British CPE successions suggests a more complex climate history during the Carnian, indicating that the CPE is not recognized by the same changes everywhere

    Palynomorphs of the Normapolles group and related plant mesofossils from the Iharkút vertebrate site, Bakony Mountains (Hungary)

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    Abstract Palynological and paleobotanical investigation of bonebeds and other strata of the Csehbánya Formation from the vertebrate locality at Iharkút (Bakony Mts, Hungary) reveals well-preserved Santonian palynological assemblages dominated by the Normapolles group, with a minor component consisting of other angiosperm pollen, some gymnosperm pollen, and spores. Eleven species of Normapolles-type pollen grains belonging to seven genera and fruit remains of a new taxon, Sphaeracostata barbackae gen. et sp. nov., are described. The new species is very abundant in the material, represented by ca. 1000 specimens. The genus Caryanthus Friis and an unnamed form previously reported from Haţeg by Lindfors et al. (2010) are also present. Plants producing Normapolles-type pollen grains diversified during the Late Cretaceous, with a bloom in the Santonian. The palynostratigraphy of the Upper Cretaceous terrestrial sediments in the studied region is based on Normapolles-related species. The studied assemblage is assigned to the Oculopollis zaklinskaiae-Tetracolporopollenites (Brecolpites) globosus Zone (or Zone C) indicating a late Santonian age. Comparison of the Iharkút palynoflora with other known Upper Cretaceous palynofloras of Central Europe shows diachronous occurrence of Normapolles taxa at different geographic localities and warrants further investigation. The ecological requirements of the amphibian fauna reflect azonal conditions controlled by the availability of water, which is in agreement with the inferred ecological conditions based on the paleobotanical investigations. The fauna is of entirely non-marine character, further supported by isotope studies, in line with our data showing that the palynological samples contain no marine forms

    Vegetation dynamics during the Late Triassic (Carnian-Norian): Response to climate and environmental changes inferred from palynology

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    Microscopic plant remains (spores and pollen) allow us to trace vegetation and detect environmental, especially climatic changes from deep time in the geological past. The Late Triassic (237-201 Ma) period is marked by an array of environmental changes such as large scale volcanism, a meteorite impact and global climate change. This study describes the response of vegetation from two periods of the Late Triassic, the Carnian (237-227 Ma) and Norian (227-209 Ma), from three locations: the UK, Hungary and SW USA

    Internationalisation (Transnationalisation) of the Enterprise Sector

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    Abstract: As part of a wider research program we analysed the theoretical framework and the recent developments of the process of internationalisation (transnationalisation) of the small- and medium-sized enterprises generally in the European Union and with a specific view on Hungary and Spain. We tried to highlight the trends and barriers of internationalisation. We carried out document analyses, interviews, analyses of statistical databases and an own data collection with online survey

    Palynological and X-ray fluorescence (XRF) data of Carnian (Late Triassic) formations from western Hungary

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    The data presented in this article are related to the research article “Palynology and weathering proxies reveal climatic fluctuations during the Carnian Pluvial Episode (CPE) (Late Triassic) from marine successions in the Transdanubian Range (western Hungary)” (Baranyi et al., 2019). Palynological and palynofacies counts and mineralogical data are presented that build the core for the palaeoenvironmental and palaeoclimatic interpretation discussed in the original research article. Other component of this data article is the description of the applied laboratory and analytical techniques. We also supply microscopic images of the identified pollen and spores and a list of all identified palynomorphs
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