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Open access

Baba Senowbari-Daryan, Sándor Kovács and Felicitász Velledits

Sponges from the Middle Triassic reef limestone of the Aggtelek Karst (NE Hungary)

The hypercalcified sponge fauna of the Middle Triassic (Anisian-Ladinian) reef limestone exposed between Aggtelek-Jósvafő-Égerszög (northern Hungary) is described. Almost all the identified species are chambered sponges ("sphinctozoa"). Only two fragments of a not determinable species of non-chambered species ("inozoa") were identified. Hexactinellid sponges are not found. The majority of the Middle Anisian "sphinctozoans" are absolutely different genera, not known from the Permian reefs. The sponge fauna of the Triassic pioneer reefs in the Aggtelek Karst are distinctly small-scaled occurring in "Tubiphytes"-dominated carbonates. The following taxa are described: Amblysiphonella sp., Celyphia zoldana Ott, Pisa & Farabegoli, Colospongia catenulata catenulata Ott, C. catenulata macrocatenulata Scholz, Follicatena cautica Ott, Kovacsia baloghi (Kovács), Solenolmia manon manon (Münster), S. radiata Senowbari-Daryan & Riedel, Olangocoelia otti Bechstädt & Brandner, Thaumastocoelia dolomitica Senowbari-Daryan, Zühlke, Bechstädt & Flügel, Thaumastocoelia cf., Th. cassiana Steinmann.

Open access

Dávid Béla Vizi, János Fehér, Attila Lovas and Sándor Kovács

Abstract

Climate change takes more and more challenges to the water management. Future predictions show that the possibility of extreme floods and drought events are increasing, thus an additional task of the water management can be the fulfilment of the increasing water demands. These new extreme hydrological situations need to be properly handled in water management. The paper presents the first modelling results of the JOINTISZA project carried out on a selected sub-basin of the Tisza River, which is endangered by hydrological extremes. Our aim was to demonstrate the applicability of a one-dimensional hydrodynamic model to study the effects of the climate change. Future hydrological trends were introduced in the river basin and it was assessed how the results of climate models can be used for further hydrodynamic modelling. To address challenges of climate change and supply the stakeholders with an adequate amount of water, proper operation of the reservoir and the irrigation canals are needed. The use of hydrological modelling can be helpful to adequately distribute water resources.

Open access

József Sándor and Lehel István Kovács

Abstract

Upper bounds for σ(n) are provided in terms of other arithmetic functions as ϕ(n), d(n), ψ(n), P(n), etc. Comparision of older results are given, too.

Open access

Krisztina Filepné Kovács, István Valánszki, Ágnes Sallay, Sándor Jombach, Zsuzsanna Mikházi and László Kollányi

Abstract

An essential condition for the success of rural areas is the harmonious enforcement of ecologic, economic, and other educational, cultural, aesthetic goods/services of landscape, diversity of landscape functions. Landscape function analysis is a useful tool for the complex evaluation of rural regions. Using statistic and spatial data, we explored the landscape resources, potentials, and limitations of two pilot regions. But what about the future? Based on the landscape function analysis, we have defined special types of regions/landscape visions according to the long-term ability to retain population by the comparison of economic, production, and habitat value of the landscape.

Open access

Andrea Harnos, Péter Fehérvári, Imre Sándor Piross, Zsolt Karcza, Nóra Ágh, Szilvia Kovács and Tibor Csörgő

Abstract

Ornithological studies often rely on large temporal scale ringing datasets as source of information. However, basic descriptive statistics of collected data are rarely provided. In order to fill this gap, here we present the first item of a series of exploratory analyses of migration timing and body size measurements of the most frequent Passerine species at a ringing station located in Central Hungary (1984–2015). First, we give a concise description of foreign ring recoveries of the Pied Flycatcher in relation to Hungary. We then shift focus to data of 2860 individuals deriving from the ringing station, where birds have been trapped, handled and ringed with standardized methodology since 1984. Timing is described through annual and daily capture and recapture frequencies and their descriptive statistics. We show annual mean arrival dates within the study period and we present the cumulative distribution of first captures with stopover durations. We present the distributions of wing, third primary, tail length and body mass, and the annual means of these variables. Furthermore, we show the distribution of individual fat and muscle scores, and the distribution of body mass within each fat score category. We distinguish migration periods (spring and autumn), age (i.e. juveniles and adults) and sex groups. Our aim is to provide a comprehensive overview of the analysed variables. However, we do not aim to interpret the obtained results, merely draw attention to interesting patterns, that may be worth exploring in detail. Data used here are available upon request for further analyses.

Open access

Anna Vozárová, Fritz Ebner, Sándor Kovács, Hans-Georg Kräutner, Tibor Szederkenyi, Branislav Krstić, Jasenka Sremac, Dunja Aljinovič, Matevž Novak and Dragomir Skaberne

Late Variscan (Carboniferous to Permian) environments in the Circum Pannonian Region

The Pennsylvanian-Cisuralian late-orogenic and post-orogenic paleoenvironments of the Circum Pannonian Region (CPR) include tectono-stratigraphic sequences developed from the Upper Bashkirian-Moscovian marine early molasse stage up to the Guadalupian-Lopingian post-orogenic stage, with gradual connection to the beginning of the Alpine (Neotethyan) sedimentary cycle. Shallow marine siliciclastic or carbonate siliciclastic overstep sequences started in the internal part of the Variscan orogenic belt during the latest Serpukhovian and Bashkirian-Moscovian. They overlapped unconformably the variably metamorphosed Variscan basement, or weakly deformed and metamorphosed foreland and syn-orogenic flysch sediments of Mississippian to Early Pennsylvanian age. The post-Variscan rifting largely affected the Variscan orogenic belt by reactivation of the Variscan lithosphere. The late- to post-orogenic terrestrial sequences started within the internal part of the Variscan orogenic belt during the Middle/Late Pennsylvanian. It continued gradually to terrestrial-shallow water carbonate-siliciclastic sequences in its external part through the Permian. According to the present configuration, the Alpine (Neotethyan) northward shifting transgression started during the Guadalupian/Lopingian in the South and during the Early Triassic in the North.

Open access

Peter Balogh, Wojciech Kapelański, Hanna Jankowiak, Lajos Nagy, Sandor Kovacs, Laszlo Huzsvai, Jozsef Popp, Janos Posta and Angela Soltesz

Abstract

The aim of this study was to compare the characteristics of the productive lifetime (PLT) of sows kept on two farms, from the aspect of reasons for culling. The study was based on data from animals from two breeding farms in Hungary, using the data of 3493 crossbred Dutch Large White and Dutch Landrace sows (DLW × DL) between their first farrowing until the time of culling (2006 and 2012). For six years, the annual culling rate for both farms averaged 45%. The most frequent reasons for removal on both farms were reproductive problems (40%, 51%), leg problems (29%, 23%) and mortality (19%, 15%). There was a significant difference between the distributions of reasons for culling on the two farms (χ2=41.7, P≤0.001). The distributions of reasons for culling differed in three periods of sow breeding (Farm A: χ2=264.7, P≤0.001; Farm B: χ2=511.1, P≤0.001). The percentage of main removal reasons decreased, whereas the frequency of culling due to age increased. Using survival analysis (Kaplan-Meier method and Cox proportional hazard model), significant differences were identified between the PLT of sows culled due to reproductive problems (P≤0.001), leg problems (P≤0.001) and old age (P≤0.001). Reproductive problems (HR: 1.34, P≤0.001) and leg problems (HR: 1.39, P≤0.001) were higher and culling due to old age (HR: 0.44, P≤0.001) was lower on Farm A compared to Farm B. There were no significant differences between the two farms in terms of mortality (HR: 0.99, P=0.923). Overall, the results can be useful for breeders of crossbred (DLW × DL) sow populations in more accurately defining their culling systems.

Open access

Ágnes Bálint, Sándor Hoffmann, Attila Anton, Tibor Szili-Kovács and György Heltai

Abstract

According to global inventories the agricultural field production contributes in a significant measure to increase of concentration of greenhouse gases (CO2, N2O, CH4) in the atmosphere, however their estimated data of emissions of soil origin differ significantly. Particularly estimates on nitrogen-oxides emissions show a great temporal and spatial variability while their formations in microbial processes are strongly influenced by biogeochemical and physical properties of the soil (eg microbial species, soil texture, soil water, pH, redox-potential and nutrient status) and land use management through the impact of the application of natural and synthetic fertilisers, tillage, irrigation, compaction, planting and harvesting. The different monitoring systems and inventory models were developed mostly from atmospheric chemistry point of view and little comprehensive data exist on the processes related to GHG emissions and their productions in agricultural soils under ecological conditions of Central Europe. This paper presents the new results of a project aimed elaboration of an experimental system suitable for studying relationships between the production and emission of greenhouse gases and plant nutrition supply in agricultural soils under Hungarian ecological conditions. The system was based on a long-term fertilisation field experiment. Mesocosm size pot experiments were conducted with soils originating from differently treated plots. The production of CO2 and N2O was followed during the vegetation period in gas traps built in 20 cm depth. Undisturbed soil columns were prepared from the untreated side parcels of the field experiment and the production of CO2 and N2O was studied at 20, 40 and 60 cm depth. A series of laboratory microcosm experiments were performed to clarify the microbial and environmental effects influencing the gas production in soils. The CO2 and N2O were determined by gas chromatography. The NOx was detected by chemiluminescence method in headspace of microcosms. In the mesocosm and soil columns experiments influence of plant nutrition methods and environmental factors was successfully clarified on seasonal dynamics and depth profile on CO2 and N2O productions. The database developed is suitable for estimating CO2 and N2O emissions from agricultural soils.