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1.

001-es BibID:BIBFORM080901
Első szerző:Braun Mihály (vegyész, analitikus)
Cím:Using linear discriminant analysis (LDA) of bulk lake sediment geochemical data to reconstruct lateglacial climate changes in the South Carpathian Mountains / M. Braun, K. Hubay, E. Magyari, D. Veres, I. Papp, M. Bálint
Dátum:2013
ISSN:1040-6182
Megjegyzések:A multi-proxy approach is widely used for reconstructing climatic change in alpine lake sediments. This study applied bulk sediment geochemistry to reconstruct lateglacial and early Holocene climatic change in a glacial lake (Lake Brazi, 1740 m a.s.l.) in the Retezat Mts. (South Carpathians, Romania). The lowermost 1 m part of a 4.9-m long sediment core, covering the period between 9950 and 15,750 cal BP, was used for high resolution bulk analysis of major elements (Al2O3, SiO2, TiO2, CaO, MgO, K2O, Na2O, Fe2O3, MnO, SO3). Linear discriminant analysis (LDA) was used to compare a priori classified main chemical groups. Subsamples from the core were priory ordered to "warm" and "cold" groups respectively, according to their age and evidence of cold and warm events in the record, as suggested by proxy correlation with the lateglacial event stratigraphy of North Greenland Ice Core Project (NGRIP). The discriminant function was calculated using concentrations of Al2O3, TiO2, CaO, MgO, K2O, Na2O, Fe2O3, and MnO after log ratio transformation. Loss-on-ignition, silicon and sulphur concentrations were not used for the discriminant analysis, but regarded as comparison proxies for checking up the validity of outputs. Sediments deposited during "cold" and "warm" events were separated significantly by the LDA function; 85.1% of the originally grouped cases were correctly classified under the LDA analysis. The calculated discriminant scores indicated four "cold" and four "warm" events. Sediments ordered into the "warm" group contained larger amounts of organic matter and sulphur, while sediment samples of the "cold" group were characterized by the overall predominance of major oxides bound into inorganic silicates. The discriminant scores showed strong correlation with the NGRIP ?18O data (r = 0.8135) and with the pollen percentage sum of trees and shrubs (r = 0.9460). Loss-on-ignition showed a somehow weaker, but still conclusive linear relationship with the discriminant scores (r = 0.7505). Discriminant analyses of bulk sediment major oxide chemical data may be a useful tool to identify the impact of climatic events upon the nature and composition of materials delivered to a lake basin.
Tárgyszavak:Természettudományok Földtudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Quaternary International. - 293 (2013), p. 114-122. -
További szerzők:Hubay Katalin (1985-) (biológus, környezetkutató) Magyari Enikő (1973-) (biológus) Veres Dániel Papp István (1980-) (vegyész) Bálint Miklós
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2.

001-es BibID:BIBFORM080855
Első szerző:Haliuc, Aritina
Cím:Palaeohydrological changes during the mid and late Holocene in the Carpathian area, central-eastern Europe / Haliuc Aritina, Veres Daniel, Brauer Achim, Hubay Katalin, Hutchinson Simon M., Begy Robert, Braun Mihaly
Dátum:2017
ISSN:0921-8181
Megjegyzések:Multi-proxy, high-resolution analyses (lithological, geochemical, environmental magnetism) anchored by 2214Cdates, of a 5.53 m long sediment core from Lake Ighiel (Romanian Carpathians, central-eastern Europe) allowedthe reconstruction of key local, catchment-lacustrine dynamics and an appraisal of palaeohydrological andpalaeoclimatic gradients acting regionally over the last 6000 years. Thefirst sedimentological phase of the recordfrom 6030 to 4200 cal yr BP is characterised by low productivity and high detrital input indicating surface runoffprocesses due to enhanced rainfall. This interpretation is in agreement with other hydrological reconstructionsreporting increased precipitation also in CE Europe, NE Mediterranean and also inferred summer and winter lat-itudinal temperature gradients (LTG) (as defined by Davis and Brewer, 2009), showing a strong connectivity be-tween basin-lacustrine dynamics and the establishment of the dominant, Atlantic atmospheric circulationpattern in the area. The lacustrine system was more stable between 4200 and 2500 cal yr BP when clastic inputsdiminished and biological productivity increased. During this interval, the coherence of Lake Ighiel's multi-century detrital events, identified in a range of proxy-data (albeit different in frequency and magnitude), withflood activity in central Europe (the Alps) suggests a common moisture forcing (Atlantic and periodically Medi-terraneaninfluences). Incontrast, different reconstructionsfrom the NEMediterraneanindicate a distinct NW-SEhydro-climatic gradient. A more complex and variable trend is depicted in Lake Ighiel sedimentation during thelast ~2500 years showing a variable detrital trend likely reflecting an intriguing hydrological pattern which is inagreement with intervals of increased aridity phases during a generally moister period. Comparing our sedimen-tological results with published pollen records from the nearby area clearly indicates anthropogenic imprintsduring the Dacian-Roman Period and especially from the Middle Ages towards the present. The ~6000-yearlong sedimentary record of Lake Ighiel contributes to our understanding of mid and late Holocenepalaeohydrological changes in the Carpathians and highlights the importance of latitudinal gradients in drivinghydrological variability in continental Europe.
Tárgyszavak:Természettudományok Földtudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Global And Planetary Change. - 152 (2017), p. 99-114. -
További szerzők:Veres Dániel Brauer, Achim Hubay Katalin (1985-) (biológus, környezetkutató) Hutchinson, Simon M. Begy, Robert Braun Mihály (1966-) (vegyész, analitikus)
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3.

001-es BibID:BIBFORM073714
Első szerző:Hubay Katalin (biológus, környezetkutató)
Cím:Holocene environmental changes as recorded in the geochemistry of glacial lake sediments from Retezat Mountains, South Carpathians / Hubay Katalin, Braun Mihály, Buczkó Krisztina, Pál Ilona, Veres Daniel, Túri Marianna, Biró Tamás, Magyari Enikő
Dátum:2018
ISSN:1040-6182
Megjegyzések:Sediment cores obtained from two deep (>15?m) glacial lakes were analyzed in context of terrestrial vegetation development and in-lake processes from the Retezat Mountains (Southern Carpathians, Romania). Only the Holocene parts were chosen for study for testing what is the connection between geochemical changes and biotas around and in the lakes. The lakes are situated at slightly different altitudes on the northern (Lake Gales, 1990 m a.s.l.) and southern slope (Lake Bucura, 2040 m a.s.l.), respectively. Changes in geochemical composition were relatively low amplitude during the studied period (10,300?1790 and 10,300?695?cal?yr BP) in both lakes, but the applicability of enrichment factor (EF) for geochemical elements and diatom ecological traits (guilds) in paleoecological reconstruction were demonstrated in this paper. The main changes have been observed at ca. 10,670?9000, 6500 and 3100?cal?yr BP in geochemistry, vegetation and siliceous algal assemblages. Catchment soil stabilization was apparent from ?9000?cal?yr BP onwards, in-lake and terrestrial productivity was the highest between 9000 and 6500?cal?yr BP and human impact became the dominant driver in both terrestrial vegetation and sediment geochemical changes and in-lake processes over the last ?3400 years in both lakes. The geochemical record displayed frequent erosional events within the Holocene. The strongest soil erosions clustered around 6500?7400 and 3200-900?cal?yr BP.
Tárgyszavak:Természettudományok Környezettudományok idegen nyelvű folyóiratközlemény külföldi lapban
holocén
környezetváltozás
geokémia
szediment
Megjelenés:Quaternary International. - 477 (2018), p. 19-39. -
További szerzők:Braun Mihály (1966-) (vegyész, analitikus) Buczkó Krisztina (1962-) (biológus) Pál Ilona Veres Dániel Túri Marianna (1988-) (geográfus-geoinformatikus) Biró Tamás Magyari Enikő (1973-) (biológus)
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4.

001-es BibID:BIBFORM080863
Első szerző:Karátson Dávid (földrajz-biológia tanár)
Cím:The latest explosive eruptions of Ciomadul (Csomád) volcano, East Carpathians : A tephrostratigraphic approach for the 51-29 ka BP time interval / D. Karátson, S. Wulf, D. Veres, E. K. Magyari, R. Gertisser, A. Timar-Gabor, Á. Novothny, T. Telbisz, Z. Szalai, V. Anechitei-Deacu, O. Appelt, M. Bormann, Cs. Jánosi, K. Hubay, F. Schäbitz
Dátum:2016
ISSN:0377-0273
Megjegyzések:The most recent, mainly explosive eruptions of Ciomadul, the youngest volcano in the Carpatho-Pannonian Region, have been constrained by detailed field volcanological studies, major element pumice glass geochemistry, luminescence and radiocarbon dating, and a critical evaluation of available geochronological data. These investigations were complemented by the first tephrostratigraphic studies of the lacustrine infill of Ciomadul's twin craters (St. Ana and Moho₀s) that received tephra deposition during the last eruptions of the volcano. Our analysis shows that significant explosive activity, collectively called EPPA (Early Phreatomagmatic and Plinian Activity), started at Ciomadul in or around the present-day Moho₀s, the older crater, at ?51 ka BP. These eruptions resulted in a thick succession of pyroclastic-fall deposits found in both proximal and medial/distal localities around the volcano, characterized by highly silicic (rhyolitic) glass chemical compositions (ca. 75.2?79.8 wt.% SiO2). The EPPA stage was terminated by a subplinian/plinian eruption at ?43 ka BP, producing pumiceous pyroclasticfall and -flow deposits of similar glass composition, probably from a "Proto-St. Ana" vent located at or around the younger crater hosting the present-day Lake St. Ana. After a quiescent period with a proposed lava dome growth in the St. Ana crater, a new explosive stage began, defined as MPA (Middle Plinian Activity). In particular, a significant two-phase eruption occurred at ~31.5 ka BP, producing pyroclastic flows from vulcanian explosions disrupting the preexisting lava dome of Sf. Ana, and followed by pumiceous fallout from a plinian eruption column. Related pyroclastic deposits show a characteristic, less evolved rhyolitic glass composition (ca. 70.2? 74.5 wt.% SiO2) and occur both in proximal and medial/distal localities up to 21 km from source. The MPA eruptions, that may have pre-shaped a crater similar to, but possibly smaller than, the present-day St. Ana crater, was followed by a so far unknown, but likewise violent last eruptive stage from the same vent, creating the final morphology of the crater. This stage, referred to as LSPA (Latest St. Ana Phreatomagmatic Activity), produced pyroclastic-fall deposits of more evolved rhyolitic glass composition (ca. 72.8?78.8 wt.% SiO2) compared to that of the previous MPA stage. According to radiocarbon age constraints on bulk sediment, charcoal and organic matter from lacustrine sediments recovered from both craters, the last of these phreatomagmatic eruptions ? that draped the landscape toward the east and southeast of the volcano ? occurred at ~29.6 ka BP, some 2000 years later than the previously suggested last eruption of Ciomadul.
Tárgyszavak:Természettudományok Földtudományok idegen nyelvű folyóiratközlemény külföldi lapban
Ciomadul
Tephrostratigraphy
Quaternary
Carpathians
Radiometric chronology
Megjelenés:Journal Of Volcanology And Geothermal Research. - 319 (2016), p. 29-51. -
További szerzők:Wulf, Sabine Veres Dániel Magyari Enikő (1973-) (biológus) Gertisser, R. Timar-Gabor A. Novothny, Á. Telbisz Tamás Szalai Zita Anechitei-Deacu, V. Appelt, O. Bormann, Marc Jánosi Csaba Hubay Katalin (1985-) (biológus, környezetkutató) Schäbitz, Frank
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5.

001-es BibID:BIBFORM080858
Első szerző:Longman, Jack
Cím:Periodic input of dust over the Eastern Carpathians during the Holocene linked with Saharan desertification and human impact / Jack Longman, Daniel Veres, Vasile Ersek, Ulrich Salzmann, Katalin Hubay, Marc Bormann, Volker Wennrich, Frank Schäbitz
Dátum:2017
ISSN:1814-9332
Megjegyzések:Reconstructions of dust flux have been used to produce valuable global records of changes in atmospheric circulation and aridity. These studies have highlighted the importance of atmospheric dust in marine and terrestrial biogeochemistry and nutrient cycling. By investigating a 10 800- year-long paleoclimate archive from the Eastern Carpathians (Romania) we present the first peat record of changing dust deposition over the Holocene for the Carpathian- Balkan region. Using qualitative (X-ray fluorescence (XRF) core scanning) and quantitative inductively coupled plasma optical emission spectrometer(ICP-OES) measurements of lithogenic (K, Si, Ti) elements, we identify 10 periods of major dust deposition between 9500-9200, 8400-8100, 7720-7250, 6350-5950, 5450-5050, 4130-3770, 3450- 2850, 2000-1450, 800-620, and 60 cal yr BP to present. In addition, we used testate amoeba assemblages preserved within the peat to infer local palaeohydroclimatic conditions. Our record highlights several discrepancies between eastern and western European dust depositional records and the impact of highly complex hydrological regimes in the Carpathian region. Since 6100 cal yr BP, we find that the geochemical indicators of dust flux have become uncoupled from the local hydrology. This coincides with the appearance of millennial-scale cycles in the dust input and changes in geochemical composition of dust. We suggest that this is indicative of a shift in dust provenance from local-regional (likely loess-related) to distal (Saharan) sources, which coin cide with the end of the African Humid Period and the onset of Saharan desertification.
Tárgyszavak:Természettudományok Földtudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
dust flux
Eastern Carpathians
Holocene
Megjelenés:Climate of the Past. - 13 : 7 (2017), p. 897-917. -
További szerzők:Veres Dániel Ersek, Vasile Salzmann, Ulrich Hubay Katalin (1985-) (biológus, környezetkutató) Bormann, Marc Wennrich, Volker Schäbitz, Frank
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6.

001-es BibID:BIBFORM079877
Első szerző:Veres Dániel
Cím:New chronological constraints for Middle Palaeolithic (MIS 6/5-3) cave sequences in Eastern Transylvania, Romania / Daniel Veres, Marian Cosac, Christoph Schmidt, George Murătoreanu, Ulrich Hambach, Katalin Hubay, Sabine Wulf, David Karátson
Dátum:2018
ISSN:1040-6182
Megjegyzések:The Middle to Upper Palaeolithic transition is one of the crucial periods of change in the prehistory of Europe due to the full emergence, continent-wide, of modern human lithic technologies, and detrimental of Neanderthal survival. Knowledge about the transition is growing, however, the evidence for cultural and technological developments for the Middle Palaeolithic in the Carpathian ? Lower Danube Basin is still rather sparse. Here we discuss latest findings arising from a chronological investigation of Middle Palaeolithic assemblages within the Varghis karst, Eastern Transylvania, Romania. Combining our first chronological results with information from previous excavations, we can distinguish two main stages of habitation (albeit Middle Palaeolithic lithics and faunal remains appear scattered throughout the investigated profile) within the Abri 122 rock shelter. In order to augment the typological cultural considerations, we applied direct radiocarbon dating on bones and charcoal from within the occupation layers. Radiocarbon dating of bones suggests that the Middle Palaeolithic sequence is older than the upper dating limit of the method, whereas direct luminescence ages on the lowermost productive horizon and immediately above it indicate surprisingly old ages of ca. 106?141 ka (OSL ? optically stimulated) or 99?174 ka (IRSL ? infrared stimulated). Multiple-protocol dating of charcoal found within the two habitation layers produced ages >38 14C ka BP, also suggesting that the lowermost lithic-rich horizon pertains to the Middle Palaeolithic industries. Overall, the recovered lithics, currently forming one of the most significant collections for Romania, are fully consistent with two main habitation phases connected to Middle Palaeolithic cultural affinities. The occurrence of a volcanic ash layer within Ursului Cave and originating from the Ciomadul volcanic complex (Carpathians) is first reported here. Recently dated to ? ? 43 (?50) ka, it might represent an important marker horizon, providing that it is identified within other Palaeolithic cave assemblages.
Tárgyszavak:Természettudományok Környezettudományok idegen nyelvű folyóiratközlemény külföldi lapban
Middle palaeolithicVarghis karstAbri 122MIS 6/5-3Carpathian tephraRomania
Megjelenés:Quaternary International. - 485 (2018), p. 103-114. -
További szerzők:Cosac, Marian Schmidt, Christoph Murătoreanu, George Hambach, Ulrich Hubay Katalin (1985-) (biológus, környezetkutató) Wulf, Sabine Karátson Dávid (1964- ) (földrajz-biológia tanár)
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7.

001-es BibID:BIBFORM080850
035-os BibID:(cikkazonosító)104112
Első szerző:Vincze Ildikó
Cím:Paleoclimate reconstruction and mire development in the Eastern Great Hungarian Plain for the last 20,000 years / Vincze Ildikó, Finsinger Walter, Jakab Gusztáv, Braun Mihály, Hubay Katalin, Veres Daniel, Deli Tamás, Szalai Zoltán, Szabó Zoltán, Magyari Enikő
Dátum:2019
ISSN:0034-6667
Megjegyzések:We present the reconstruction of mire vegetation changes and fire history recorded in a continuous sediment profile that spans the last 20,000 cal yr BP from the Late Pleniglacial to Holocene in North-eastern Hungary. We also aimed to reveal past climate changes by using ecological requirements of specific aquatic plants as summer temperature indicators. Our results suggest the formation of a mesotrophic mire around 20,000 cal yr BP with brown moss, Betula sp. and Selaginella selaginoides cover beside the occurrence of Phragmites australis, Typha latifolia and T. angustifolia suggesting base-rich fen and tundra-like wet-ground habitats on the lakeshore. This community shifted to reed dominated swamp at c. 18,300 cal yr BP with inferred min. July temperatures of 12-15.7 °C. pinus sp., Betula nana, B. pendula/pubescens, Hippuris vulgaris and P. australis dominated until 16,600 cal yr BP pointing to shallow muddy stagnant water and colder climatic conditions than in the preceding interval. The most warmth-demanding species, T. latifolia and T. angustifolia indicated July mean temperatures > 14-15.7 °C soon after the LGM. The formation of biogenic carbonate also started at an early stage; major accumulation occurred between 15,200 and 10,000 cal yr BP. In the Early Holocene, environmental indicator species (e.g., Phragmites australis and T. latifolia) pointed to warmer and shallower conditions, while the late Holocene was characterized by strong eutrophication and reed swamp dominance on the lakeshore. Elevated macrocharcoal concentration, wood fragments and remains of Typha species suggested frequent local fires and dry mire surface conditions during the last 1700 years.
Tárgyszavak:Természettudományok Földtudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:Review Of Palaeobotany And Palynology. - 271 (2019), p. 1-21. -
További szerzők:Finsinger, Walter Jakab Gusztáv Braun Mihály (1966-) (vegyész, analitikus) Hubay Katalin (1985-) (biológus, környezetkutató) Veres Dániel Deli Tamás Szalai Zoltán Szabó Zoltán Magyari Enikő (1973-) (biológus)
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