Lótusz Nagyváradról : a püspökfürdői hévízi tündérrózsa eredetének kérdése

The Egyptian white waterlilly (Nymphaea lotus L.) is a perennial, tropical, subtropical species of waterlily (Nymphaea) genus. There is a conspicuous satellite occurance in Europe, in a thermal lake called Lake Petea near to Oradea city, NW Romania which was found by Pál Kitalibel in 1798. The plant which lives in this thermal lake was described as the variation of Nymphaea lotus (Nymphaea lotus L. var. thermalis) by János Tuzson. Its origin has been part of great debate among scholars during the last 200 years. Some of the scholars’ opinion is that it is a Tertiary relict, others advocate its origin as a result of plantation by human population or recent dispersal by waterbirds. This is one of the several questions we try to answer in our research which treats the environmental history of Lake Petea. The results of the malacological examintations and preliminary radiocarbon analysis suggest that Nymphaea lotus var. thermalis is not a Tertiary relict and these results also show that it is not a result of human activity

Methodological add-ons to a non-destructive, micro-CT-based taxonomic/morphometric analysis of characean remains

Ever since its introduction, computed tomography has come a long way. No longer is it merely a method that is used in clinical diagnostics, but it is becoming more and more popular among palaeontologists because it can be used to analyse both external and internal structures of fossil remains, such as small insects, snail shells and plant remains. The present study describes non-destructive analyses of Late Cretaceous and early Holocene charophyte gyrogonites by using the micro-CT technique, from sample preparation (embedding, fixing) to visualisation and assessment of images obtained. In addition to this non-destructive examination, we wished to test whether or not computed tomography could be used to examine the gyrogonites. Our preliminary results have made it clear that the micro-CT technique is worth employing for further research. It has proved possible to visualise the samples in 3D, rotate them, and observe them from different directions. By using the appropriate parameters, we have also been able to observe density differences between parts of characean remains and to study several important defining features of these

Methodological add-ons to a non-destructive, micro-CT-based taxonomic/morphometric analysis of characean remains

Ever since its introduction, computed tomography has come a long way. No longer is it merely a method that is used in clinical diagnostics, but it is becoming more and more popular among palaeontologists because it can be used to analyse both external and internal structures of fossil remains, such as small insects, snail shells and plant remains. The present study describes non-destructive analyses of Late Cretaceous and early Holocene charophyte gyrogonites by using the micro-CT technique, from sample preparation (embedding, fixing) to visualisation and assessment of images obtained. In addition to this non-destructive examination, we wished to test whether or not computed tomography could be used to examine the gyrogonites. Our preliminary results have made it clear that the micro-CT technique is worth employing for further research. It has proved possible to visualise the samples in 3D, rotate them, and observe them from different directions. By using the appropriate parameters, we have also been able to observe density differences between parts of characean remains and to study several important defining features of these

Identification and environmental background of Chara remains in the Holocene sequence of Lake Peţea (NW Romania) and the possibilities of using the results in archaeobotany [A Szent László-tó (ÉNY-Románia) holocén kori szelvényében található chara maradványok azonosítása és környezeti háttere, valamint az eredmények archeobotanikai felhasználásának lehetőségei]

The charophyte remains play an important role in the reconstruction of the hydrological characteristics (pH, water depth, stream flow, carbonate content, isotope geochemistry-water chemistry and temperature) of the former lake habitats. This is of particular importance in environmental historical studies, since the possibilities for obtaining aquatic food resources and the techniques and tools used are fundamentally influenced by these hydrological conditions. Our gyrogonite samples were recovered from the Holocene sequence of the thermalspring fed Lake Peţea NW Romania. The presence of the recovered Chara cf. hispida Linnaeus, 1753 gyrogonites marks the emergence of an oligotrophic shallow water lake system characterized by high dissolved Ca and Mg content and relatively poor plant cover in the Early Holocene. The results of previous malacological and ostracod studies also indicate the development of a shallow water lake with a muddy substrate and water temperatures above 18°C. As a warm-water lake, the local micro-environment was also home to many exploitable tree species. The charophyte remains that we recovered were from the Mesolithic level of the lake, so we were able to provide information on the hydrology of the lake for this period. Unfortunately, there have been no detailed archaeological investigations in the area to date revealing any potentially Mesolithic remains. Thus, no information is currently available on actual human occupation from the period in question

Environmental history of the Csorna Plain (Western Danube Plain, NW Hungary) from the Late Glacial to the Late Holocene as seen from data of multiproxy geoarchaeological investigations

This study presents the results of a comprehensive geoarchaeological study implemented at an archeological site covering ca. 5 ha near the city of Csorna on the NW part of the Danube Plain, NW Hungary. The site itself exposed a complex fluvial system of an ice age creek with near bank and overbank areas (levee, point bar, back swamp). Spatial distribution of archeological features allowed for the interpretation of differential use of the fluvial landscape by different cultures. According to our data, the referred fluvial system must have emerged during the Late Glacial. At this time, creeks originating from hills to the SE followed a uniform NW trajectory. From the Holocene, small creeks were beheaded turning into inactive flood channels. It was the time when the gradual infilling of the floodplain started. Alternating layers of floodwater coarses and floodplain fines mark recurring floods at our site. These could have been correlated with cooler, wetter climatic phases of the North Atlantic, Western Europe and high stands in Central European lakes. Highest floods are recorded during the Late Bronze and Iron Ages besides the Neolithic. Pollen data enabled us to make inferences on the vegetation as well

Identification and environmental background of Chara remains in the Holocene sequence of Lake Peţea (NW Romania) and the possibilities of using the results in archaeobotany = A Szent László-tó (ÉNy-Románia) holocén kori szelvényében található Chara maradványok azonosítása és környezeti háttere, valamint az eredmények archeobotanikai felhasználásának lehetőségei

The charophyte remains play an important role in the reconstruction of the hydrological characteristics (pH, water depth, stream flow, carbonate content, isotope geochemistry-water chemistry and temperature) of the former lake habitats. This is of particular importance in environmental historical studies, since the possibilities for obtaining aquatic food resources and the techniques and tools used are fundamentally influenced by these hydrological conditions. Our gyrogonite samples were recovered from the Holocene sequence of the thermalspring fed Lake Peţea NW Romania. The presence of the recovered Chara cf. hispida Linnaeus, 1753 gyrogonites marks the emergence of an oligotrophic shallow water lake system characterized by high dissolved Ca and Mg content and relatively poor plant cover in the Early Holocene. The results of previous malacological and ostracod studies also indicate the development of a shallow water lake with a muddy substrate and water temperatures above 18°C. As a warm-water lake, the local micro-environment was also home to many exploitable tree species. The charophyte remains that we recovered were from the Mesolithic level of the lake, so we were able to provide information on the hydrology of the lake for this period. Unfortunately, there have been no detailed archaeological investigations in the area to date revealing any potentially Mesolithic remains. Thus, no information is currently available on actual human occupation from the period in question. = A csillárkamoszat maradványok fontos szerepet játszanak az egykori tavi élőhelyek hidrológiai jellemzőinek (pH, vízmélység, áramlás, karbonáttartalom, izotópgeokémia-vízkémia és hőmérséklet) rekonstrukciójában. Ez különösen fontos a környezettörténeti vizsgálatokban, mivel a vízi táplálékforrások megszerzésének lehetőségeit, valamint az alkalmazott technikákat és eszközöket alapvetően befolyásolják ezek a hidrológiai viszonyok. Chara girogonit mintáinkat az ÉNy-Romániában található, termálforrás táplálta Szent László-tó holocén rétegsorából nyertük. A megtalált Chara cf. hispida Linnaeus, 1753 girogonitok jelenléte egy oligotróf sekélyvízi tórendszer kialakulását jelzi, amelyet magas oldott Ca és Mg tartalom és viszonylag szegényes növénytakaró jellemzett a koraholocénben. A korábbi malakológiai és Ostracoda vizsgálatok eredményei szintén egy sekély vizű, iszapos aljzatú, 18°C feletti vízhőmérsékletű tó kialakulására utalnak. Meleg vizű tóként a helyi mikrokörnyezet számos hasznosítható fafajnak is otthont adott. Az általunk vizsgált Chara maradványok a tó mezolit szintjéről származnak, így a tó hidrológiai viszonyairól erre az időszakra vonatkozóan tudtunk információt szolgáltatni. Sajnos a területen eddig nem folytak részletes régészeti kutatások, amelyek egyértelműen mezolit maradványokat tártak volna fel. Így jelenleg nem áll rendelkezésre információ a kérdéses időszak tényleges antropogén hatásaira vonatkozóan