Time filter

Source Type

Cluj-Napoca, Romania

Tantau I.,Babes - Bolyai University | Tantau I.,Institute of Biological Researches | Geanta A.,Babes - Bolyai University | Geanta A.,Emil Racovita Institute of Speleology | And 3 more authors.
Carpathian Journal of Earth and Environmental Sciences | Year: 2014

Pollen and spore analysis from a 150 cm long peat sequence taken from a high altitude oligotrophic peat bog (1810 m) located in the Rodna Mountains and constrained by AMS radiocarbon dates provides new insights into the postglacial vegetation history, human activities and paleoclimate in the high elevation area of the Eastern Carpathians. Betula, Pinus and Alnus were the first taxa that have spread in the area, due to the temperature increase that characterized the early Holocene (ca. 11200 cal yr BP). Pinus diploxylon type (P. mugo and P. sylvestris) dominated the local and regional landscapes during the early Holocene until 10500 cal yr BP, but receded markedly afterwards. After 10500 cal yr BP Picea abies was the most important constituent in the local vegetation below the site. The dynamic of the thermophilous deciduous forest (Ulmus, Quercus, Tilia, and Fraxinus) is poorly recorded because of the high altitude of the studied site. Corylus avellana became regionally established around 10500 cal yr BP. Carpinus betulus and Fagus sylvatica were established at 6500 and 5300 cal yr BP respectively. Pollen evidences for human influence are represented by cereals and herbaceous taxa specific to grazed surfaces from about 1050 cal yr BP on. The grazing pressure increased between 600 and 160 cal yr BP. Source

Ujvari Z.,Eotvos Lorand University | Calugar A.,Institute of Biological Researches
Acta Zoologica Academiae Scientiarum Hungaricae | Year: 2010

Three zerconid mites Prozercon katae UJVÁRI et CǍLUGǍR sp. n., Zercon atypicus UJVÁRI et CǍLUGǍR sp. n., Zercon dentatus UJVÁRI et CǍLUGǍR sp. n. described from Romania. Three species, Zercon similifoveolatus IVAN et CǍLUGǍR, 2004, Z. marinae IVAN et CǍLUGǍR, 2004 and Z. magdae IVAN et CǍLUGǍR, 2004, are redescribed. Source

Tantau I.,Babes - Bolyai University | Farcas S.,Institute of Biological Researches | Beldean C.,Babes - Bolyai University | Geanta A.,Babes - Bolyai University | Stefanescu L.,Babes - Bolyai University
Carpathian Journal of Earth and Environmental Sciences | Year: 2011

A 4800-year-long sequence of environmental change during the Late Holocene has been reconstructed for southern Transylvania (Romania). The research design used palynological methods to reconstruct vegetation history and human impact in the region. We present here the results of pollen analysis of one sequence of about 11.90 m length, originating from a peat bog near Avrig (113 pollen spectra). The vegetation record, which is supported by four 14C dates, starts in the Subboreal with the Carpinus optimum. The first indications of human activities in the region appear at around 4600 cal yr BP. Some environmental changes were possibly linked with natural phenomena. A colder period that begins at about 600-700 cal yr BP could be correlated with the LIA event (Little Ice Age). However, the most significant changes were initiated between 2500 and 180 cal yr BP and were directly or indirectly associated with human occupation. These human-induced effects included major forest clearance, fire, agriculture and grazing. Source

Tantau I.,Babes - Bolyai University | Feurdean A.,Senckenberg Institute | Feurdean A.,Romanian Academy Emil Racovita Institute of Speleology | De Beaulieu J.-L.,Aix - Marseille University | And 2 more authors.
Journal of Quaternary Science | Year: 2014

Although few compared with Western Europe, continental records from Central-Eastern Europe are increasingly confirming that rapid climate fluctuations of the past 15 000 years are also present in records situated far from the North Atlantic region. In the present study a new pollen record supported by 11 AMS 14C dates, from Luci (Eastern Romanian Carpathians), was used to reconstruct the Lateglacial and Holocene vegetation history of the region, and the sensitivity to past climate change and human impact. The results showed that vegetation composition reacted particularly sensitively to the climatic oscillations that occurred during the Allerød (13 800 cal a BP), the Younger Dryas (YD) and at the transition from the YD to the Holocene (11 700 cal a BP), although smaller amplitude vegetation changes also occurred at ca. 14 700 cal a BP (Greenland Interstadial (GI)-1e; Bølling), 13 900 cal a BP (GI1-d; Older Dryas) and 13 200 cal a BP (GI-1b; intra-Allerød cooling). However, the amplitude of vegetation response in the continental part of Europe was smaller as compared with the records from Greenland and the North Atlantic region. The Holocene began with the expansion of Betula, Ulmus and Picea abies, followed by Fraxinus, Quercus, Tilia and Corylus avellana from about 10 000 cal a BP when the climate became warmer and drier. Picea abies has been the dominant tree species for almost the entire Holocene period. The spread of Carpinus betulus occurred at ca. 5800 cal a BP, with maximum values between 5100 and 3100 cal a BP, while Fagus sylvatica spread at ca. 3100 cal a BP and attained maximum values between 2800 and 200 cal a BP. However, during the last 200 years, Fagus sylvatica and Picea abies forests have largely been replaced by Pinus. Human impact in the area is noted from ca. 4200 cal a BP onwards but it is expressed rather weakly until 1200 cal a BP, and primarily relates to forest clearance and grazing. © 2014 John Wiley & Sons, Ltd. Source

Tantau I.,Babes - Bolyai University | Feurdean A.,Senckenberg Institute | de Beaulieu J.-L.,Aix - Marseille University | Reille M.,Aix - Marseille University | Farcas S.,Institute of Biological Researches
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2011

Pollen analysis supported by nine AMS 14C dates from the Poiana Ştiol peat sequence (1540m), in the Rodnei Mountains, Eastern Romanian Carpathians (Romania) is used to reconstruct the Holocene vegetation history in this mountain region. The results are then compared with other sequences from Romania and Eastern Europe in order to better understand the past dynamics of the main forest constituents. The vegetation record at Poiana Ştiol starts at ca. 11,000calyr BP, with the occurrence of rather closed woodlands composed of Betula, Pinus, Picea abies, Alnus, A. viridis, and Ulmus. Picea abies was the dominant tree species for almost the entire period. However, during the last 3000years, P. abies forests were largely replaced by Pinus in the area. Temperate tree taxa (Fraxinus, Quercus, Acer, Tilia, and Corylus avellana) were also common but likely at lower elevation. C. avellana expanded around 10,300calyr BP and reached maximum values after 9000calyr BP. Pollen of Carpinus betulus and Fagus sylvatica was already recorded around 7000calyr BP. However, the spread of C. betulus occurred at ca. 6000calyr BP, with maximum values between 4800calyr BP and 3000calyr BP, while F. sylvatica spread from ca. 3200calyr BP and attained maximum values between 2000 and 200calyr BP. The first indications of human activities appeared around 3200calyr BP and intensified within the last 200years. Comparison with other sequences from Romania and surrounding countries reveals both similarity and great differences related to the location of glacial refugia, climate change and human impact. © 2011 Elsevier B.V. Source

Discover hidden collaborations